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Participating in mobility: People with schizophrenia driving motorized vehicles Tilman Steinert, Fabian Veit, Peter Schmid, Brendan Jacob Snellgrove, Raoul Borbé
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S0165-1781(15)00309-1 http://dx.doi.org/10.1016/j.psychres.2015.05.034 PSY8916
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Psychiatry Research
Received date: 15 January 2015 Revised date: 26 May 2015 Accepted date: 28 May 2015 Cite this article as: Tilman Steinert, Fabian Veit, Peter Schmid, Brendan Jacob Snellgrove, Raoul Borbé, Participating in mobility: People with schizophrenia driving motorized vehicles, Psychiatry Research, http://dx.doi.org/10.1016/j.psychres.2015.05.034 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Participating in mobility: people with schizophrenia driving motorized vehicles Tilman Steinert, Fabian Veit, Peter Schmid, Brendan Jacob Snellgrove, Raoul Borbé
Address: Prof.Dr. Tilman Steinert Centres for Psychiatry Suedwuerttemberg Weingartshofer Str. 2 88214 Ravensburg Weissenau e-mail: [email protected]
(same address for the other authors)
Abstract Participation of people with schizophrenia in individual mobility is an important aspect of inclusion according to the UN convention of human rights of persons with disabilities. However, driving motorized vehicles can be dangerous due to positive, negative, and cognitive symptoms, side effects of antipsychotic drugs and concomitant substance abuse. The objective of this study was to explore the patterns of individual mobility in a representative patient population, to determine predictors for active use of motorized vehicles, and to compare the results with data of the general population in the respective region. We interviewed N=150 participants with schizophrenia or schizoaffective disorder, 66 in-patients and 84 out-patients, in different types of out-patient services. A questionnaire developed for this purpose was used in interviews. 64 % of the participants had a driving licence, 32 % had driven a motorized vehicle in the past year, 31 % owned a car, 2 % a motor bike. The driving licence had been withdrawn from 24.7 % of participants, 32.7 % reported having been involved in a road accident. Participants drove considerably less in time and distances than the general population. Significant variables determining the chance of active use of motorized vehicles in a logistic regression model were Global Assessment of Functioning (GAF) (OR 1.04 per each point), number of previous admissions (OR 0.52 per admission), and history of driving under alcohol or drugs (OR 0.18). Key words: schizophrenia, participation, UN convention, driving, motor vehicle
Introduction The UN Convention on the Rights of Persons with Disabilities (UN-CRPD) is an international human rights treaty of the United Nations intended to protect the rights and dignity of persons with disabilities. The text was adopted by the United Nations General Assembly in 2006, it came into force in 2008. By 2014, it had been signed by 158 countries and 147 parties, including the European Union. The purpose of the convention is "to promote, protect and ensure the full and equal enjoyment of all human rights and fundamental freedoms by all persons with disabilities, and to promote respect for their inherent dignity“ (United Nations, 2008). People with mental impairments are explicitly mentioned as persons to whom the convention refers. The general ideas of the UN-CRPD are respect for human dignity, non-discrimination, full and effective participation and inclusion in society, respect for difference, equality of opportunities, accessibility, a gender perspective and a special perspective for children. These basic principles, particularly those of participation and inclusion, are also relevant for the personal mobility of disabled persons, to which article 20 of the UN-CRPD refers to by warranting „… effective measures to ensure personal mobility with the greatest possible independence for persons with disabilities…“. In developed societies, the most important and widespread measure of personal mobility is active use of motorized vehicles. The principles of the UN-CRPD are considered as valid for all persons with disabilities, induding mental disorders. However it is well known that cognitive, affective and behavioural disturbances can pose a risk when driving motorized vehicles (Vaa, 2003). Thus there can be a conflict between aspects of safety for the public and the aim of social inclusion and participation of people with mental disorders in individual mobility. This applies particularly to people with schizophrenia. Schizophrenia can lead to inability to drive a motor vehicle due to positive symptoms, such as delusions or hallucinations, negative symptoms, for example psychomotor retardation, and cognitive symptoms, for instance attention deficits and difficulties of stimulus discrimination. Antipsychotics can relieve psychotic symptoms but can affect ability to drive a motor vehicle themselves due to side effects such as sedation (Brunnauer et al., 2004). Further, substance abuse disorders are approximately four times more frequent in people with schizophrenia, than in the general population (Hartz et al., 2014). On the other hand, they represent the major group of people severely disabled by mental disorder in younger years, needing comprehensive support for inclusion and participation (Switaj et al., 2012). Obviously, individual mobility is highly dependent on the prevailing social conditions and ideas of the times. While in many developing countries motor vehicles are affordable only for a small minority of the population, in other countries, particularly in North America, individual use of motorized vehicles is so common that the public transport system is underdeveloped and being reliant on it can impose severe restrictions. Further, considerable differences may exist between urban and rural areas as to the availability of public transport systems. Particularly outside of big cities, motor vehicles are so important for maintaining private relationships and leisure activities, and attending pubic events that inability to drive can lead to considerable social exclusion.Against this background, data regarding individual mobility of people with schizophrenia in their respective societal context is required as well as evidence regarding obstacles to participation in mobility, and available alternatives. Surprisingly, nonwithstandig the considerable prevalence of psychotic disorders and an increased political interest in issues of inclusion and participation, this topic has scarcely been elucidated in the literature until now. Some work is available regarding accident risks for persons with mental disorder, little for those with schizophrenia. The IMMORTAL study, funded by the European Union, provided a meta-analysis of the accident risk of people with different somatic and mental disorders (Vaa, 2003). Accordingly, the relative risk was 2.00 for alcoholism, 1.71 for mental disorders in general, and 2.01 for ‚severe mental disturbances‘. Only few studies were conducted examining individuals with schizophrenia in terms of their use of transport and mobility. A first study from the US conducted in the 1980ies compared 103 outpatients with schizophrenia with a matched sample of 123 controls. 68 % of patients with schizophrenia but nearly all controls drove motor vehicles; patients drove less and caused more accidents (Edmund et al., 1989). Another study done in California compared 83 out-patients with schizophrenia and a mean age of 59 years with 46 demographically matched normal comparison subjects. 43 % of patients but nearly all controls were drivers. Functional status was correlated with negative but not positive symptoms (Palmer et al., 2002). In a recent study from Mexico with a small sample of 28 people with schizophrenia, 64 % had problems with ‚using transportation‘, and only 3.6 % used a motor vehicle, suggesting huge differences to the conditions in the U.S. (Tenorio-Martinez et
al., 2009). To our knowledge, no other studies are available at present, particularly none from Europe. The objective of this study was to explore patterns of individual mobility and predictors of motor vehicle use in a representative sample of people with schizophrenia in a mixed urban/rural area in Southern Germany. Methods Sample and study site The study was conducted in the region north of the Lake of Constance, including the districts Landkreis Ravensburg and Bodenseekreis, covering 2300 km2 and with a population of about 460.000, several towns with up to 80.000 inhabitants and many villages. The region is prosperous in comparison to the German average. In terms of statistics, 50.6 % of the inhabitants and 85.5 % of all households in Germany own a motorized vehicle. With regard to mental health services, the region is well supplied with three psychiatric hospitals, several day clinics and different out-patient services, including out-patient clinics (so-called institute ambulances) and psychiatrists in private practice, but accessible for everybody. A wide range of community mental health services is available for everybody, including offers of home visits. The sample size was determined a priori to be N=150, composed of patients from in-patient and different out-patient services. The in-patients were recruited from the three hospitals (Weissenau, Wangen, Friedrichshafen), the out-patients from two institute ambulances and one private psychiatric practice. The composition of the sample was intended to roughly reflect the numbers of patients treated in the respective services. In-patients were asked for participation consecutively. In the outpatient services, one of the researchers asked all attending patients for participation on certain days, including different weekdays without preference, until the intended sample size was reached. Inclusion criteria were schizophrenic disorder with a clinically established diagnosis according to ICD-10 (F 20, F25), written informed consent, and age ≥ 18 years. Exclusion criteria were inability to follow an interview due to severe cognitive disorders, lack of German language skills or acute psychotic states, comorbidity with somatic brain disorder, and comorbidity with somatic disorders resulting in impairments of mobility. No exclusion criteria were applied in terms of driving history, i.e. also subjects who had never acquired a driving licence due to early onset of illness were included. For comparison, available public data for the general population in the region described above was used. 2.2. Instruments Sociodemographic data was gathered from the validated German psychiatric basic data documentation (Jaeger et al., 2011). Diagnoses were recorded from the patients‘ charts. For the purpose of the study, a questionnaire was developed under participation of several experienced researchers. Several revisions were made after pilot tests with patients. The questionnaire contained 23 questions related to patient’s individual mobility, vehicle use, obstacles of participation in mobility, loss of driving licence and accidents. The questionnaire was conducted as an interview by the same researcher (F.V.) in all cases. After the interview, patients performed the trail making test type A (TMT-A). The trail making test is a simple cognitive task testing attention and visuomotor processing speed. It is commonly used as a screening test for cognitive dysfunction, in the US it is recommended by the National Highway Traffic Safety Administration for tests of ability to drive, particularly for elderly people (Dobbs and Shergill, 2013; Stutts et al., 1998). Since the focus of our study was social inclusion and functioning, we did not assess psychopathological symptoms and actual intake of medication, but social functioning. To this end, we used the Global Assessment of Functioning (GAF) (Jones et al, 1995) which was determined in all cases by one of the authors (F.V.) after previous training. We did not attempt to include objective data on driving history, as available in German national registers, because the required consent by the patient for gathering such sensible data would have inevitably led to considerable sample selection bias. All data, including accidents, were self-reported. For indications of kilometers per year, the interviewer tried to support the participants in plausible calculations. 2.4. Ethics The study was approved by the ethics committee of the University of Ulm. The study has therefore been performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments. All participants gave written informed consent. Patients‘ files were not examined. Participants received 10 € after the interview. 2.5. Statistical methods
Gender differences and differences between in-patients and out-patients were calculated by Chi square test and Fisher’s exact test respectively, t-test and Mann-Whitney U-test according to the nature of the data. Due to multiple testing, the level of significance was determined as 0.05 for sample description (table 1) and 0.01 for all results obtained from the interview related to driving. No meaningful differences were seen between in-patients and out-patients, so that we will not differentiate between these two subgroups in reporting our results. As the objective of this study was to investigate patient characteristics associated with active use of motorized vehicles, a logistic regression model was calculated. The dependent variable was dichotomous (active participation in individual motor traffic yes/no). As no literature on influential variables was available, we chose as independent variables those which were available and which we supposed to be potentially influential. However, the number was limited with regards to sample size. Independent variables included were gender, age, inpatient/out-patient status, GAF score, result of the trail making test, number of psychiatric admissions as an in-patient, duration of illness since first psychiatric admission, being under guardianship, and previous traffic participation under influence of alcohol or drugs. First, we calculated a cross-table with Spearman’s rank correlations among all variables to check multicollinearity. Variables with a correlation of ≥ 0.6 should not be entered together into the model. This was not the case, all correlations were smaller (results not indicated in the results section). In a next step, a model with all 9 variables was calculated. Subsequently, variables were removed in a stepwise-back procedure, removing the variable with the lowest p value in the G statistics. The level of significance was determined as p < .05. The goodness of fit was assessed with a Chi-square test. As coefficient of determination McFadden’s R-square was calculated. All calculations were done with Statistica® (Stratsoft Inc., 2001). Results The characteristics of the participants are displayed in table 1. Results were grouped by gender, taking into account that attitudes and habits with respect to driving could differ between genders. In the trail making test type A the mean time for performance was 58.3 seconds, indicating cognitive dysfunction in a part of the sample. However, 62.7 % of participants were in the normal range (less than 51 seconds). Results of the interview related to individual mobility and driving are displayed in table 2. 73.3 % of participants reported that they had driven a motorized vehicle within the last five years, but considerably less, 32 %, within the last 12 months. Reasons given for using a motorized vehicle were mostly leisure (70%), shopping (66.7 %), and going to work (42%). 24.6 % of the participants lost their driving licence at least once, 6,7 % failed to regain it in a subsequent medical-psychological examination. Reasons for withdrawal of the driving licence were alcohol (35.1 %), speeding (29.7 %), hit-and-run accident (24.3 %), illegal drugs (21.6 %), and illness-related odd behaviours (8.1 %) (multiple answers permitted). Public transportation was used by 57.6 % of the sample with a median of 1716 km/year (we report the median because all distributions were highly skewed). Those 28.6 % who used a motorized vehicle indicated a median of 4160 km/year, those 32.7 % who used a bicycle a median of 1040 km/year and the median distance covered as a pedestrian was 728 km/year. 76 (50.7%) of the participants reported going on holiday at least every second year, the preferred form of transportation being aircraft, as stated by 50 (33.3%) participants. Table 4 displays some of these results in comparison to available data for the general population from different sources. It shows that the study participants used less motorcars but more bicylcles and public transportation for their individual mobility in comparison to the general population. In the stepwise-back logistic regression model driving a motorized vehicle within the past 12 months was the dependent variable. This was reported by 32.0 % of the sample. Independent variables entered into the model were gender, in-patient/out-patient status, GAF score, result of the trail making test, number of psychiatric admissions as an in-patient, duration of illness since first psychiatric admission, being under guardianship, and previous traffic participation under influence of alcohol or drugs. The stepwise-back procedure resulted in a model with GAF score, number of psychiatric admissions and participation under influence of alcohol or drugs as independent variables (table 3). Only three variables had a significant effect. Most significantly, a self-reported history of driving under alcohol or drugs diminished the chance to belong to the group of active drivers within the past 12 months by 82 %, signified by an odds ratio of .18. Also previous psychiatric hospitalizations decreased this chance, by 48 % per each admission. In contrast, a better level of social functioning increased the chance of active driving. The OR of 1.042 means that by each point on the GAF scale the chance of active
driving increased by 4.2 %. Having a guardianship, cognitive performance, duration of illness, gender, and in-patient vs. out-patient status had no independent significant influence. Discussion Our results show for the first time that a considerable part of people with schizophrenia own a driving licence and participate in public traffic as active drivers even after a mean duration of illness of nearly two decades. The main obstacles for driving are functional impairment and substance abuse. The results presented here have to be interpreted in two relevant contexts. Firstly, how valid are they for people with schizophrenia? Secondly, what do they mean in terms of participation, i.e., are there relevant differences to the general population in the region investigated? With regards to representativity, we tried to take a sample derived from the different in-patient and out-patient services in the region according to their relative weight in terms of patients treated. Men were over-represented in our sample, which is explained at least partly by their over-representation in the respective services. The sample characteristics are rather similar compared with a sample of 374 in-patients with schizophrenia recruited for a different study in the same region some years ago (Längle et al., 2012), only the percentage of females and the number of previous admissions were lower. The percentage of people with non-German citizenship was exactly that of the general population of the region (State of Baden-Württemberg, 2012). However, our sample fails to meet representativity for at least three important groups, which is a drawback of nearly all clinical samples of patients with psychotic disorders: Those unable to cooperate for a study due to the severity of their illness, those not in any treatment setting due to lack of insight into illness, due to negative attitudes towards psychiatric services, or due to practical barriers to get in touch with psychiatric services, and those who are only mildly ill and do not need specialized psychiatric treatment or do not need treatment at all. These groups represent extremes on both sides. It can therefore be assumed that failure to include them leads to reduced observed variance without considerable changes in observed means and proportions. With respect to the societal context, conditions are obviously considerably different from the only similar study, done in Mexico with a small sample (Tenorio-Martinez et al., 2009), where only 4.6 % of the subjects used a car. For the general population in Germany, no significant differences are reported between urban and rural areas. Therefore it was possible to transfer the data to the investigated region as indicated in table 4. Data on distances covered as pedestrian in the general population are not available, but a mean distance of more than 700 km per year reported by our participants seems considerable. Similar to the general population, men in our sample used vehicles of all kind slightly more frequently than women, but differences failed to reach significance. Integrating all results, it becomes clear that people with schizophrenia drive motorized vehicles considerably less frequently and for shorter distances than the general population. They evade to public transport, and, to a considerable extent, to riding a bicycle and walking. Both functional impairments and financial restrictions may be responsible. Nevertheless, the frequency with which our participants go on holiday trips, preferably by aircraft, is remarkable and indicates some participation of mentally disabled people in societal wealth. With respect to involvement in accidents, no directly comparable data is available from the general population. In the investigated region, 7.8 % of road accidents recorded by police were caused by drugs or alcohol (Glaser, 2007). This data set does not suggest an increased involvement of people with schizophrenia or other mental illness, though not reported separately and probably unknown. Conclusions on the risk per kilometer driven cannot be drawn from our results. However, people with schizophrenia do not seem to account for a relevant proportion of road accidents (Soyka et al., 2014), which might be explained by them driving motorized vehicles less frequently, and actual incidents possibly being caused rather by secondary alcohol abuse than by psychosis itself. With regards to treatment, it is well-known from trials with driving simulators that antipsychotic medication can have a negative impact on some outcome measures such as speed and reaction time, but less than benzodiazepines and tricyclic antidepressants (Rapoport & Banina, 2007). On the other hand, most patients benefit from medication in terms of improving not only psychotic symptoms but also their cognitive performance so that for a considerable proportion of them medication adherence can be considered as a necessary requirement for driving (de las Cuevas et al., 2010). However, a considerable proportion of people with schizophrenia is considerably impaired with respect to driving skills due to their illness (Brunnauer et al., 2009).
Our multivariate model provided evidence that a history of driving under the influence of alcohol or drugs is the most important factor excluding persons with psychosis from driving a motorized vehicle, just as in the general population. From the perspective of inclusion and participation, co-morbidity with substance abuse and dependency is deleterious for this highly vulnerable population. According to the results, impairments of functioning (indicated by the GAF) and relapses (indicated by number of psychiatric admissions) are crucial factors leading to loss of individual mobility. Both can be considered as indicators of severity of illness. Interestingly, the results of cognitive functioning in the TMT-A had no independent significant influence. However, GAF and TMT-A results were correlated with r = -.465 suggesting that effects of cognitive dysfunction are included in the GAF score and do not add a significant independent contribution. If in addition to an illness with considerable severity and disability driving under alcohol or drugs occurs, definitive loss of participation becomes highly probable. Another important aspect of social inclusion of people with mental disorders is stigma and the desire for social distance in the general population (Angermeyer & Matschinger, 2005). With respect to stigma, our results are ambiguous. That patients with schizophrenia drive motorcars, do it for the same reasons as other people and lose their driving licence for the same reasons as others supports the assumption of a continuum and may reduce stigma (Schomerus et al., 2013; von dem Knesebeck et al., 2013). However, driving under alcohol or drugs as a typical risk is not a good message to reduce stigma. This study has some strengths and several limitations. Strengths are the carefully chosen sample composition and the thorough elucidation of the subject by personal interview, filling a gap in the previously sparse data on this subject. Weaknesses are the inevitable sample selection bias as discussed above and, mainly, the exclusive reliance of the results on the participants‘ subjective reports. It was not possible to verify any statement on driving licences, accidents, etc. by objective data. The same applied to indications on kilometers driven per year, even if the interviewer tried to achieve plausible results by repeated questions and going into details. A further limitation is that illness-related aspects such as psychopathology, medication, treatment adherence could not be determined and cognitive functioning was assessed only only in few domains as measured by theTMT-A. Complex everyday tasks and driving in particular are affected by general cognitive status rather than by visual components (Lipskaya-Velikowksky et al., 2013). Conclusions Driving motorized vehicles is an important aspect of social inclusion in developed countries. People with schizophrenia are vulnerable in this respect. Functional impairment, relapses, and substance abuse lead to loss of participation. In therapeutic attempts to improve adherence, the individual importance of driving and the related dangers and obstacles should be addressed at an early stage. Contributors Tilman Steinert designed the study and wrote most parts of the paper. Fabian Veit conducted all interviews and phrased the application for the ethics committee. Peter Schmid did the calculations. Brendan Snellgrove wrote parts of the paper. Raoul Borbé conducted literature research and provided ideas and the theoretical framework as well as final phrasing of the manuscript. Conflicts of Interest: On behalf of all authors, the corresponding author states that there is no conflict of interest. References Angermeyer, M.C., Matschinger H, 2005. Labeling –stereotype – discrimination. An investigation of the stigma process. Social Psychiatry and Psychiatric Epidemiology, 40, 391-395. Association of German Transportation Companies, 2013. Statistics 2012. Annual Report 2013. (Verband Deutscher Verkehrsunternehmen (VDV). Statistik 2012. Jahresbericht (2013). http://www.vdv.de/statistik-2012.pdfx?forced=true). Accessed 11 Dec 2014
Brunnauer, A., Laux, G., Geiger, E., Möller, J.H., 2004. The impact of antipsychotics on psychomotor performance with regard to car driving skills. Journal of Clinical Psychopharmacology 24, 155-160. Brunnauer, A.,Laux, G., Zwick, S., 2009. Driving simulator performance and psychomotor functions of schizophrenic patients treated with antipsychotics. European Archives of Psychiartry and Clinical Neurosciences 259, 483-489. De Las Cuevas, C., Ramallo, Y., Sanz, E.J., 2010. Psychomotor performance and fitness to drive: the influence of psychiatric disease and its pharmacological treatment. Psychiatry Research 176, 236-241. Dobbs, B.M., Shergill, S.S., 2013. How effective is the Trail Making Test (Parts A and B) in identifying cognitively impaired drivers? Age Ageing, 42, 577-581. Edlund, M.J., Conrad, C., Morris, P., 1989. Accidents among schizophrenic outpatients. Comprehensive Psychiatry 30, 522-526. Glaser, D., 2007. Road traffic accidents in Baden-Wuerttemberg (Straßenverkehrsunfälle in BadenWürttemberg). Statistisches Monatsheft Baden-Württemberg 11, 42-47. Hartz, S.M., Pato, C.N., Medeiros, H., Cavazos-Rehg, P., Sobell, J.L., Knowles, J.A., Bierut, L.J., Pato, M.T., Genomic Psychiatry Cohort Consortium, 2014. Comorbidity of severe psychotic disorders with measures of substance use. JAMA Psychiatry 71, 248-254. Jaeger, S., Flammer, E., Steinert, T., 2011. Basic documentation in clinical practice: how reliable is the data? Psychiatrische Praxis 38, 244-249. Jones, S.T., Thornicroft, G., Coffey, M., Dunn, G.,1995. A brief mental health outcome scale reliability and validity of the Global Assessment of Functioning (GAF). British Journal of Psychiatry 166, 654-659. Karlsruhe Institute for Traffic and Mobility, 2011. German Mobility Panel, Report 2011. (Karlsruher Institut für Verkehrswesen. Deutsches Mobilitätspanel Bericht 2011. Alltagsmobilität & Tankbuch). http://daten.clearingstelle-verkehr.de/192/85/Bericht_MOP_10_11.pdf. Accessed 11 Dec 2014 Kunert, U., Radke, S., Chlond, B., Kagerbauer, M., 2012. Motor vehicle mobility: driving accomplishment countinuously increasing in 2011. German Institute for Economic Research Week Report 79, 3-14. Längle, G., Steinert, T., Weiser, P., Schepp, W., Jaeger, S., Pfiffner, C., 2012. Effects of polypharmacy on outcome in patients with schizophrenia in routine psychiatric treatment. Acta Psychiatrica Scandinavica 125, 372-381. Lipskaya-Velikovsky, L., Kotler, M., Weiss, P., Kaspi, M., Gamzo, S., & Ratzon, N., 2013. Car driving in schizophrenia: can visual memory and organization make a difference?. Disability & Rehabilitation, 35: 1734-1739. Palmer, B.W., Heaton, R.K., Gladsjo, J.A., Evans, J.D., Patterson, T.L., Golshan, S., 2002. Heterogenity in functional status among older outpatients with schizophrenia: employment history, living situation and driving. Schizophrenia Research, 55, 205-215. Rapoport, M.J.,Banina, M.C., 2007. Impact of psychotropic medications on simulated driving: a critical review. CNS Drugs, 21, 503-519. Schomerus, G., Matschinger, H., Angermeyer, M.C., 2013. Continuum beliefs and stigmatizing attitudes towards persons with schizophrenia, depression and alcohol dependence. Psychiatry Research 209, 665-669. Soyka, M., Dittert, S., Kagerer-Volk, S., Soyka, M., 2014. Driving ability with alcohol and drug dependence and schizophrenia. Nervenarzt 85, 816-821. State of Baden-Württemberg, 2012. Population statistics 2012 (Land Baden-Württemberg. Bevölkerungsstatistik 2012). http://www.baden-wuerttemberg.de/de/unser-land/landundleute/bevoelkerung/ Accessed 12 Dec 2014 STATISTICA for Windows edition 6, Stratsoft, Inc. 2001., 2300 East 14th Street, Tulsa. Stutts, J., Stewart, J., Martell, C., 1998. Cognitive test performance and crash risk in an older driver population. Accident Analysis and Prevention 30, 337-346.
Świtaj, P., Anczewska, M., Chrostek, A., Sabariego, C., Cieza, A., Bickenbach, J., Chatterji, S., 2012 Disability and schizophrenia: a systematic review of experienced psychosocial difficulties. BMC Psychiatry12, 193. Tenorio-Martinez, R., Lara-Munoz, M., Medina-Mora, M.E., 2009. Measurement of problems in activities and parcipitation in patients with anxiety, depression and schizophrenia using the ICF checklist. Social Psychiatry and Psychiatric Epidemiology 44, 377-384. United Nations, 2008. Convention on the Rights of Persons with Disabilities. http://www.un.org/disabilities/convention/conventionfull.shtml. Accessed 5 Nov 2014 Vaa, T., 2003. Impairment, diseases, age and their relative risks of accident involvement: Results from a meta-analysis. IMMORTAL Report. https://www.toi.no/getfile.php/Publikasjoner/T%C3%98I%20rapporter/2003/690-2003/690-2003el.pdf. Accessed 12 Dec 2014 von dem Knesebeck, O., Mnich, E., Kofahl, C., Makowski, A. C., Lambert, M., Karow, A., Makowski, A.C., Lambert, M., Karov, A., Bock, T., Härter, M., Angermeyer, M. C., 2013. Estimated prevalence of mental disorders and the desire for social distance—Results from population surveys in two large German cities. Psychiatry research 209, 670-674.
Table 1: Characteristics of participants (N = 150) female N=56
male N=94
total N=150
age (years)
46.9* (SD 12.8)
42.5 (SD 11.8)
45.2 (SD 12,3)
out-patients
29 (34.5%)
55 (65.5%)
84 (56%)
in-patients
27 (40.9%)
39 (59.1%)
66 (44%)
secondary diagnosis of alcohol-related disorder
1 (1.8%)*
8 (8.5%)
9 (6%)
secondary diagnosis of drug-related disorder
1 (1.8%)*
13 (13.8%)
14 (9.3%)
other psychiatric co-morbidity
20 (35.7%)
24 (25.5%)
41 (29.3 %)
somatic co-morbidity
24 (42.9%)
30 (31.9%)
54 (36 %)
years since 1st psychiatric admission
19 (SD 13.2)
15.5 (11.9)
16.8 (SD 12.6)
number of psychiatric admissions
4.5 (SD 2.0)
4.1 (SD 2.2)
4.3 (SD 2.1)
single, divorced or widowed
44 (78.6%)
85 (90.4%)
129 (86 %)
non-German citizenship
7 (12.5%)
10 (10.6%)
17 (11.3 %)
paid workplace (including sheltered workshop)
23 (41.1%)
50 (53.2%)
73 (48.7 %)
supported living
21 (37.5%)
45 (47.9%)
66 (44 %)
legal guardianship
22 (39.3%)
45 (47.9%)
67 (44.7 %)
GAF
36.1 (SD 9.4)
37.0 (SD 8.6)
36.6 (SD 8.3)
trail making test type A (seconds)
69.3 (SD 42.7)
51.8 (SD 34.8)
58.3 (SD 38.5)
*difference female/male p
Participating in mobility: People with schizophrenia driving motorized vehicles Tilman Steinert, Fabian Veit, Peter Schmid, Brendan Jacob Snellgrove, Raoul Borbé
www.elsevier.com/locate/psychres
PII: DOI: Reference:
S0165-1781(15)00309-1 http://dx.doi.org/10.1016/j.psychres.2015.05.034 PSY8916
To appear in:
Psychiatry Research
Received date: 15 January 2015 Revised date: 26 May 2015 Accepted date: 28 May 2015 Cite this article as: Tilman Steinert, Fabian Veit, Peter Schmid, Brendan Jacob Snellgrove, Raoul Borbé, Participating in mobility: People with schizophrenia driving motorized vehicles, Psychiatry Research, http://dx.doi.org/10.1016/j.psychres.2015.05.034 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Participating in mobility: people with schizophrenia driving motorized vehicles Tilman Steinert, Fabian Veit, Peter Schmid, Brendan Jacob Snellgrove, Raoul Borbé
Address: Prof.Dr. Tilman Steinert Centres for Psychiatry Suedwuerttemberg Weingartshofer Str. 2 88214 Ravensburg Weissenau e-mail: [email protected]
(same address for the other authors)
Abstract Participation of people with schizophrenia in individual mobility is an important aspect of inclusion according to the UN convention of human rights of persons with disabilities. However, driving motorized vehicles can be dangerous due to positive, negative, and cognitive symptoms, side effects of antipsychotic drugs and concomitant substance abuse. The objective of this study was to explore the patterns of individual mobility in a representative patient population, to determine predictors for active use of motorized vehicles, and to compare the results with data of the general population in the respective region. We interviewed N=150 participants with schizophrenia or schizoaffective disorder, 66 in-patients and 84 out-patients, in different types of out-patient services. A questionnaire developed for this purpose was used in interviews. 64 % of the participants had a driving licence, 32 % had driven a motorized vehicle in the past year, 31 % owned a car, 2 % a motor bike. The driving licence had been withdrawn from 24.7 % of participants, 32.7 % reported having been involved in a road accident. Participants drove considerably less in time and distances than the general population. Significant variables determining the chance of active use of motorized vehicles in a logistic regression model were Global Assessment of Functioning (GAF) (OR 1.04 per each point), number of previous admissions (OR 0.52 per admission), and history of driving under alcohol or drugs (OR 0.18). Key words: schizophrenia, participation, UN convention, driving, motor vehicle
Introduction The UN Convention on the Rights of Persons with Disabilities (UN-CRPD) is an international human rights treaty of the United Nations intended to protect the rights and dignity of persons with disabilities. The text was adopted by the United Nations General Assembly in 2006, it came into force in 2008. By 2014, it had been signed by 158 countries and 147 parties, including the European Union. The purpose of the convention is "to promote, protect and ensure the full and equal enjoyment of all human rights and fundamental freedoms by all persons with disabilities, and to promote respect for their inherent dignity“ (United Nations, 2008). People with mental impairments are explicitly mentioned as persons to whom the convention refers. The general ideas of the UN-CRPD are respect for human dignity, non-discrimination, full and effective participation and inclusion in society, respect for difference, equality of opportunities, accessibility, a gender perspective and a special perspective for children. These basic principles, particularly those of participation and inclusion, are also relevant for the personal mobility of disabled persons, to which article 20 of the UN-CRPD refers to by warranting „… effective measures to ensure personal mobility with the greatest possible independence for persons with disabilities…“. In developed societies, the most important and widespread measure of personal mobility is active use of motorized vehicles. The principles of the UN-CRPD are considered as valid for all persons with disabilities, induding mental disorders. However it is well known that cognitive, affective and behavioural disturbances can pose a risk when driving motorized vehicles (Vaa, 2003). Thus there can be a conflict between aspects of safety for the public and the aim of social inclusion and participation of people with mental disorders in individual mobility. This applies particularly to people with schizophrenia. Schizophrenia can lead to inability to drive a motor vehicle due to positive symptoms, such as delusions or hallucinations, negative symptoms, for example psychomotor retardation, and cognitive symptoms, for instance attention deficits and difficulties of stimulus discrimination. Antipsychotics can relieve psychotic symptoms but can affect ability to drive a motor vehicle themselves due to side effects such as sedation (Brunnauer et al., 2004). Further, substance abuse disorders are approximately four times more frequent in people with schizophrenia, than in the general population (Hartz et al., 2014). On the other hand, they represent the major group of people severely disabled by mental disorder in younger years, needing comprehensive support for inclusion and participation (Switaj et al., 2012). Obviously, individual mobility is highly dependent on the prevailing social conditions and ideas of the times. While in many developing countries motor vehicles are affordable only for a small minority of the population, in other countries, particularly in North America, individual use of motorized vehicles is so common that the public transport system is underdeveloped and being reliant on it can impose severe restrictions. Further, considerable differences may exist between urban and rural areas as to the availability of public transport systems. Particularly outside of big cities, motor vehicles are so important for maintaining private relationships and leisure activities, and attending pubic events that inability to drive can lead to considerable social exclusion.Against this background, data regarding individual mobility of people with schizophrenia in their respective societal context is required as well as evidence regarding obstacles to participation in mobility, and available alternatives. Surprisingly, nonwithstandig the considerable prevalence of psychotic disorders and an increased political interest in issues of inclusion and participation, this topic has scarcely been elucidated in the literature until now. Some work is available regarding accident risks for persons with mental disorder, little for those with schizophrenia. The IMMORTAL study, funded by the European Union, provided a meta-analysis of the accident risk of people with different somatic and mental disorders (Vaa, 2003). Accordingly, the relative risk was 2.00 for alcoholism, 1.71 for mental disorders in general, and 2.01 for ‚severe mental disturbances‘. Only few studies were conducted examining individuals with schizophrenia in terms of their use of transport and mobility. A first study from the US conducted in the 1980ies compared 103 outpatients with schizophrenia with a matched sample of 123 controls. 68 % of patients with schizophrenia but nearly all controls drove motor vehicles; patients drove less and caused more accidents (Edmund et al., 1989). Another study done in California compared 83 out-patients with schizophrenia and a mean age of 59 years with 46 demographically matched normal comparison subjects. 43 % of patients but nearly all controls were drivers. Functional status was correlated with negative but not positive symptoms (Palmer et al., 2002). In a recent study from Mexico with a small sample of 28 people with schizophrenia, 64 % had problems with ‚using transportation‘, and only 3.6 % used a motor vehicle, suggesting huge differences to the conditions in the U.S. (Tenorio-Martinez et
al., 2009). To our knowledge, no other studies are available at present, particularly none from Europe. The objective of this study was to explore patterns of individual mobility and predictors of motor vehicle use in a representative sample of people with schizophrenia in a mixed urban/rural area in Southern Germany. Methods Sample and study site The study was conducted in the region north of the Lake of Constance, including the districts Landkreis Ravensburg and Bodenseekreis, covering 2300 km2 and with a population of about 460.000, several towns with up to 80.000 inhabitants and many villages. The region is prosperous in comparison to the German average. In terms of statistics, 50.6 % of the inhabitants and 85.5 % of all households in Germany own a motorized vehicle. With regard to mental health services, the region is well supplied with three psychiatric hospitals, several day clinics and different out-patient services, including out-patient clinics (so-called institute ambulances) and psychiatrists in private practice, but accessible for everybody. A wide range of community mental health services is available for everybody, including offers of home visits. The sample size was determined a priori to be N=150, composed of patients from in-patient and different out-patient services. The in-patients were recruited from the three hospitals (Weissenau, Wangen, Friedrichshafen), the out-patients from two institute ambulances and one private psychiatric practice. The composition of the sample was intended to roughly reflect the numbers of patients treated in the respective services. In-patients were asked for participation consecutively. In the outpatient services, one of the researchers asked all attending patients for participation on certain days, including different weekdays without preference, until the intended sample size was reached. Inclusion criteria were schizophrenic disorder with a clinically established diagnosis according to ICD-10 (F 20, F25), written informed consent, and age ≥ 18 years. Exclusion criteria were inability to follow an interview due to severe cognitive disorders, lack of German language skills or acute psychotic states, comorbidity with somatic brain disorder, and comorbidity with somatic disorders resulting in impairments of mobility. No exclusion criteria were applied in terms of driving history, i.e. also subjects who had never acquired a driving licence due to early onset of illness were included. For comparison, available public data for the general population in the region described above was used. 2.2. Instruments Sociodemographic data was gathered from the validated German psychiatric basic data documentation (Jaeger et al., 2011). Diagnoses were recorded from the patients‘ charts. For the purpose of the study, a questionnaire was developed under participation of several experienced researchers. Several revisions were made after pilot tests with patients. The questionnaire contained 23 questions related to patient’s individual mobility, vehicle use, obstacles of participation in mobility, loss of driving licence and accidents. The questionnaire was conducted as an interview by the same researcher (F.V.) in all cases. After the interview, patients performed the trail making test type A (TMT-A). The trail making test is a simple cognitive task testing attention and visuomotor processing speed. It is commonly used as a screening test for cognitive dysfunction, in the US it is recommended by the National Highway Traffic Safety Administration for tests of ability to drive, particularly for elderly people (Dobbs and Shergill, 2013; Stutts et al., 1998). Since the focus of our study was social inclusion and functioning, we did not assess psychopathological symptoms and actual intake of medication, but social functioning. To this end, we used the Global Assessment of Functioning (GAF) (Jones et al, 1995) which was determined in all cases by one of the authors (F.V.) after previous training. We did not attempt to include objective data on driving history, as available in German national registers, because the required consent by the patient for gathering such sensible data would have inevitably led to considerable sample selection bias. All data, including accidents, were self-reported. For indications of kilometers per year, the interviewer tried to support the participants in plausible calculations. 2.4. Ethics The study was approved by the ethics committee of the University of Ulm. The study has therefore been performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments. All participants gave written informed consent. Patients‘ files were not examined. Participants received 10 € after the interview. 2.5. Statistical methods
Gender differences and differences between in-patients and out-patients were calculated by Chi square test and Fisher’s exact test respectively, t-test and Mann-Whitney U-test according to the nature of the data. Due to multiple testing, the level of significance was determined as 0.05 for sample description (table 1) and 0.01 for all results obtained from the interview related to driving. No meaningful differences were seen between in-patients and out-patients, so that we will not differentiate between these two subgroups in reporting our results. As the objective of this study was to investigate patient characteristics associated with active use of motorized vehicles, a logistic regression model was calculated. The dependent variable was dichotomous (active participation in individual motor traffic yes/no). As no literature on influential variables was available, we chose as independent variables those which were available and which we supposed to be potentially influential. However, the number was limited with regards to sample size. Independent variables included were gender, age, inpatient/out-patient status, GAF score, result of the trail making test, number of psychiatric admissions as an in-patient, duration of illness since first psychiatric admission, being under guardianship, and previous traffic participation under influence of alcohol or drugs. First, we calculated a cross-table with Spearman’s rank correlations among all variables to check multicollinearity. Variables with a correlation of ≥ 0.6 should not be entered together into the model. This was not the case, all correlations were smaller (results not indicated in the results section). In a next step, a model with all 9 variables was calculated. Subsequently, variables were removed in a stepwise-back procedure, removing the variable with the lowest p value in the G statistics. The level of significance was determined as p < .05. The goodness of fit was assessed with a Chi-square test. As coefficient of determination McFadden’s R-square was calculated. All calculations were done with Statistica® (Stratsoft Inc., 2001). Results The characteristics of the participants are displayed in table 1. Results were grouped by gender, taking into account that attitudes and habits with respect to driving could differ between genders. In the trail making test type A the mean time for performance was 58.3 seconds, indicating cognitive dysfunction in a part of the sample. However, 62.7 % of participants were in the normal range (less than 51 seconds). Results of the interview related to individual mobility and driving are displayed in table 2. 73.3 % of participants reported that they had driven a motorized vehicle within the last five years, but considerably less, 32 %, within the last 12 months. Reasons given for using a motorized vehicle were mostly leisure (70%), shopping (66.7 %), and going to work (42%). 24.6 % of the participants lost their driving licence at least once, 6,7 % failed to regain it in a subsequent medical-psychological examination. Reasons for withdrawal of the driving licence were alcohol (35.1 %), speeding (29.7 %), hit-and-run accident (24.3 %), illegal drugs (21.6 %), and illness-related odd behaviours (8.1 %) (multiple answers permitted). Public transportation was used by 57.6 % of the sample with a median of 1716 km/year (we report the median because all distributions were highly skewed). Those 28.6 % who used a motorized vehicle indicated a median of 4160 km/year, those 32.7 % who used a bicycle a median of 1040 km/year and the median distance covered as a pedestrian was 728 km/year. 76 (50.7%) of the participants reported going on holiday at least every second year, the preferred form of transportation being aircraft, as stated by 50 (33.3%) participants. Table 4 displays some of these results in comparison to available data for the general population from different sources. It shows that the study participants used less motorcars but more bicylcles and public transportation for their individual mobility in comparison to the general population. In the stepwise-back logistic regression model driving a motorized vehicle within the past 12 months was the dependent variable. This was reported by 32.0 % of the sample. Independent variables entered into the model were gender, in-patient/out-patient status, GAF score, result of the trail making test, number of psychiatric admissions as an in-patient, duration of illness since first psychiatric admission, being under guardianship, and previous traffic participation under influence of alcohol or drugs. The stepwise-back procedure resulted in a model with GAF score, number of psychiatric admissions and participation under influence of alcohol or drugs as independent variables (table 3). Only three variables had a significant effect. Most significantly, a self-reported history of driving under alcohol or drugs diminished the chance to belong to the group of active drivers within the past 12 months by 82 %, signified by an odds ratio of .18. Also previous psychiatric hospitalizations decreased this chance, by 48 % per each admission. In contrast, a better level of social functioning increased the chance of active driving. The OR of 1.042 means that by each point on the GAF scale the chance of active
driving increased by 4.2 %. Having a guardianship, cognitive performance, duration of illness, gender, and in-patient vs. out-patient status had no independent significant influence. Discussion Our results show for the first time that a considerable part of people with schizophrenia own a driving licence and participate in public traffic as active drivers even after a mean duration of illness of nearly two decades. The main obstacles for driving are functional impairment and substance abuse. The results presented here have to be interpreted in two relevant contexts. Firstly, how valid are they for people with schizophrenia? Secondly, what do they mean in terms of participation, i.e., are there relevant differences to the general population in the region investigated? With regards to representativity, we tried to take a sample derived from the different in-patient and out-patient services in the region according to their relative weight in terms of patients treated. Men were over-represented in our sample, which is explained at least partly by their over-representation in the respective services. The sample characteristics are rather similar compared with a sample of 374 in-patients with schizophrenia recruited for a different study in the same region some years ago (Längle et al., 2012), only the percentage of females and the number of previous admissions were lower. The percentage of people with non-German citizenship was exactly that of the general population of the region (State of Baden-Württemberg, 2012). However, our sample fails to meet representativity for at least three important groups, which is a drawback of nearly all clinical samples of patients with psychotic disorders: Those unable to cooperate for a study due to the severity of their illness, those not in any treatment setting due to lack of insight into illness, due to negative attitudes towards psychiatric services, or due to practical barriers to get in touch with psychiatric services, and those who are only mildly ill and do not need specialized psychiatric treatment or do not need treatment at all. These groups represent extremes on both sides. It can therefore be assumed that failure to include them leads to reduced observed variance without considerable changes in observed means and proportions. With respect to the societal context, conditions are obviously considerably different from the only similar study, done in Mexico with a small sample (Tenorio-Martinez et al., 2009), where only 4.6 % of the subjects used a car. For the general population in Germany, no significant differences are reported between urban and rural areas. Therefore it was possible to transfer the data to the investigated region as indicated in table 4. Data on distances covered as pedestrian in the general population are not available, but a mean distance of more than 700 km per year reported by our participants seems considerable. Similar to the general population, men in our sample used vehicles of all kind slightly more frequently than women, but differences failed to reach significance. Integrating all results, it becomes clear that people with schizophrenia drive motorized vehicles considerably less frequently and for shorter distances than the general population. They evade to public transport, and, to a considerable extent, to riding a bicycle and walking. Both functional impairments and financial restrictions may be responsible. Nevertheless, the frequency with which our participants go on holiday trips, preferably by aircraft, is remarkable and indicates some participation of mentally disabled people in societal wealth. With respect to involvement in accidents, no directly comparable data is available from the general population. In the investigated region, 7.8 % of road accidents recorded by police were caused by drugs or alcohol (Glaser, 2007). This data set does not suggest an increased involvement of people with schizophrenia or other mental illness, though not reported separately and probably unknown. Conclusions on the risk per kilometer driven cannot be drawn from our results. However, people with schizophrenia do not seem to account for a relevant proportion of road accidents (Soyka et al., 2014), which might be explained by them driving motorized vehicles less frequently, and actual incidents possibly being caused rather by secondary alcohol abuse than by psychosis itself. With regards to treatment, it is well-known from trials with driving simulators that antipsychotic medication can have a negative impact on some outcome measures such as speed and reaction time, but less than benzodiazepines and tricyclic antidepressants (Rapoport & Banina, 2007). On the other hand, most patients benefit from medication in terms of improving not only psychotic symptoms but also their cognitive performance so that for a considerable proportion of them medication adherence can be considered as a necessary requirement for driving (de las Cuevas et al., 2010). However, a considerable proportion of people with schizophrenia is considerably impaired with respect to driving skills due to their illness (Brunnauer et al., 2009).
Our multivariate model provided evidence that a history of driving under the influence of alcohol or drugs is the most important factor excluding persons with psychosis from driving a motorized vehicle, just as in the general population. From the perspective of inclusion and participation, co-morbidity with substance abuse and dependency is deleterious for this highly vulnerable population. According to the results, impairments of functioning (indicated by the GAF) and relapses (indicated by number of psychiatric admissions) are crucial factors leading to loss of individual mobility. Both can be considered as indicators of severity of illness. Interestingly, the results of cognitive functioning in the TMT-A had no independent significant influence. However, GAF and TMT-A results were correlated with r = -.465 suggesting that effects of cognitive dysfunction are included in the GAF score and do not add a significant independent contribution. If in addition to an illness with considerable severity and disability driving under alcohol or drugs occurs, definitive loss of participation becomes highly probable. Another important aspect of social inclusion of people with mental disorders is stigma and the desire for social distance in the general population (Angermeyer & Matschinger, 2005). With respect to stigma, our results are ambiguous. That patients with schizophrenia drive motorcars, do it for the same reasons as other people and lose their driving licence for the same reasons as others supports the assumption of a continuum and may reduce stigma (Schomerus et al., 2013; von dem Knesebeck et al., 2013). However, driving under alcohol or drugs as a typical risk is not a good message to reduce stigma. This study has some strengths and several limitations. Strengths are the carefully chosen sample composition and the thorough elucidation of the subject by personal interview, filling a gap in the previously sparse data on this subject. Weaknesses are the inevitable sample selection bias as discussed above and, mainly, the exclusive reliance of the results on the participants‘ subjective reports. It was not possible to verify any statement on driving licences, accidents, etc. by objective data. The same applied to indications on kilometers driven per year, even if the interviewer tried to achieve plausible results by repeated questions and going into details. A further limitation is that illness-related aspects such as psychopathology, medication, treatment adherence could not be determined and cognitive functioning was assessed only only in few domains as measured by theTMT-A. Complex everyday tasks and driving in particular are affected by general cognitive status rather than by visual components (Lipskaya-Velikowksky et al., 2013). Conclusions Driving motorized vehicles is an important aspect of social inclusion in developed countries. People with schizophrenia are vulnerable in this respect. Functional impairment, relapses, and substance abuse lead to loss of participation. In therapeutic attempts to improve adherence, the individual importance of driving and the related dangers and obstacles should be addressed at an early stage. Contributors Tilman Steinert designed the study and wrote most parts of the paper. Fabian Veit conducted all interviews and phrased the application for the ethics committee. Peter Schmid did the calculations. Brendan Snellgrove wrote parts of the paper. Raoul Borbé conducted literature research and provided ideas and the theoretical framework as well as final phrasing of the manuscript. Conflicts of Interest: On behalf of all authors, the corresponding author states that there is no conflict of interest. References Angermeyer, M.C., Matschinger H, 2005. Labeling –stereotype – discrimination. An investigation of the stigma process. Social Psychiatry and Psychiatric Epidemiology, 40, 391-395. Association of German Transportation Companies, 2013. Statistics 2012. Annual Report 2013. (Verband Deutscher Verkehrsunternehmen (VDV). Statistik 2012. Jahresbericht (2013). http://www.vdv.de/statistik-2012.pdfx?forced=true). Accessed 11 Dec 2014
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Table 1: Characteristics of participants (N = 150) female N=56
male N=94
total N=150
age (years)
46.9* (SD 12.8)
42.5 (SD 11.8)
45.2 (SD 12,3)
out-patients
29 (34.5%)
55 (65.5%)
84 (56%)
in-patients
27 (40.9%)
39 (59.1%)
66 (44%)
secondary diagnosis of alcohol-related disorder
1 (1.8%)*
8 (8.5%)
9 (6%)
secondary diagnosis of drug-related disorder
1 (1.8%)*
13 (13.8%)
14 (9.3%)
other psychiatric co-morbidity
20 (35.7%)
24 (25.5%)
41 (29.3 %)
somatic co-morbidity
24 (42.9%)
30 (31.9%)
54 (36 %)
years since 1st psychiatric admission
19 (SD 13.2)
15.5 (11.9)
16.8 (SD 12.6)
number of psychiatric admissions
4.5 (SD 2.0)
4.1 (SD 2.2)
4.3 (SD 2.1)
single, divorced or widowed
44 (78.6%)
85 (90.4%)
129 (86 %)
non-German citizenship
7 (12.5%)
10 (10.6%)
17 (11.3 %)
paid workplace (including sheltered workshop)
23 (41.1%)
50 (53.2%)
73 (48.7 %)
supported living
21 (37.5%)
45 (47.9%)
66 (44 %)
legal guardianship
22 (39.3%)
45 (47.9%)
67 (44.7 %)
GAF
36.1 (SD 9.4)
37.0 (SD 8.6)
36.6 (SD 8.3)
trail making test type A (seconds)
69.3 (SD 42.7)
51.8 (SD 34.8)
58.3 (SD 38.5)
*difference female/male p
