Personality and Mental Health (2012) Published online in Wiley Online Library (wileyonlinelibrary.com) DOI 10.1002/pmh.1206
Personality dysfunction and social functioning in schizophrenia
GILES NEWTON-HOWES1,2,3,4 AND REGINALD MARSH, 1Hawkes Bay DHB, Napier, New Zealand; 2 Imperial College, London, UK; 3Wellington School of Medicine, Otago University, New Zealand; 4 Auckland University School of Medicine, c/- 76 Wellesley Road, Napier South, Napier, New Zealand ABSTRACT Aim – To determine if personality dysfunction is associated with poorer clinical and social indicators in patients with schizophrenia. Methodology – An observational study of patients with schizophrenia in psychiatric care assessed patient satisfaction with care, social functioning and psychopathology. Analysis of the relationship between personality and these three domains quantitatively assessed differences between patients with and without comorbid personality dysfunction. Diagnostic confounding was assessed using partial correlation coefficients. Results – Forty-five patients with schizophrenia were studied. In the schizophrenia group, personality dysfunction correlated with poorer social functioning but not poorer satisfaction with care. Linear regression found that the relationship between poorer social functioning and personality disorder in schizophrenia remained, taking other diagnoses and age into account. Partial correlation coefficients confirmed that this was no related to an overlap between personality and schizophrenia symptoms in this sample. Conclusion – Personality dysfunction may negatively influence social functioning in patients with schizophrenia but does not appear to impact on patients’ views of the care they receive. This is not due to the potential for diagnostic confounding between schizophrenia and personality disorder. Further research using larger samples is needed to confirm this association. Copyright © 2012 John Wiley & Sons, Ltd. Introduction There is a growing interest in understanding the impact of personality in axis I disorders, and this interest has led to a growing understanding of the potential impact of personality in disorders such as depression (Mulder, 2002; Newton-Howes, Tyrer, & Johnson, 2006), bipolar affective disorder (Bieling, Green, & Macqueen, 2007), substance use disorders (Walter et al., 2009) and anxiety disorders (Harned, Rizvi, & Linehan, 2010; Newton-Howes, Tyrer, & Weaver, 2010). Recently, longitudinal personality disorder studies have reported on the
Copyright © 2012 John Wiley & Sons, Ltd.
impact of personality in multiple axis I disorders (Shea et al., 2004) and suggest that personality disorder negatively impacts on many of the major mental disorders. This identifies personality as a focus of attention considering management options and is no longer a ‘diagnosis of exclusion’ (Snowden & Kane, 2003). It may also explain in some part why many interventions in patients with these axis I disorders are partly responsive to treatment, remaining deficits being related to the personality component of their presentation rather than the axis I disorder. What is notable about this body of literature is the relative absence of data on personality
(2012) DOI: 10.1002/pmh
Newton-Howes and Marsh
function in patients with schizophrenia, despite the fact that this mental disorder affects as much as 1% of the population and is associated with poor symptomatic and functional outcomes. Even the prevalence of personality disorder in schizophrenia is poorly characterized (Newton-Howes, Tyrer, Yang, & North, 2008), and reviews of the literature have failed to find longitudinal papers that report on the outcomes in patients with schizophrenia and comorbid personality disorder (Newton-Howes, Tyrer, Moore, & Nur, 2007). The reasons for this are unclear but may be due to the conceptual difficulties with the personality disorder construct. Surveys of personality disorder experts find that even this group has a negative view of the current DSM conceptualization of personality pathology (Bernstein et al., 2007), although there is widespread disagreement about how to better categorize the construct. There are strong arguments for a dimensional approach to characterizing personality, although this may prove difficult to use in everyday clinical settings; there is evidence that it could improve utility of diagnosis (Samuel & Widiger, 2011). Certainly, the research into what these dimensions might be and the second order facets involved is highly complex (Livesley, 2011) and would probably greatly reduce clinical utility for the practicing psychiatrist. Others advocate a general approach to a diagnosis of personality disorder, preferring a clinically oriented severity measure with subsequent trait domains (Tyrer P, Crawford M, Mulder R. et al., 2011). These diagnostic issues are also raised by prominent schizophrenia researchers (Van Os, 2009), although schizophrenia as a clinical entity is well developed and routinely used in clinical practice, a statement that is not generally true of personality disorder. Despite these diagnostic issues, studies suggest that personality can be reliably tested in patients with schizophrenia by using a test–retest methodology (Kentros et al., 1997) and this problem is one that rests with all personality research. Such conceptual difficulties have also been raised with the diagnosis of schizophrenia and schizophrenia research, where the current
Copyright © 2012 John Wiley & Sons, Ltd.
categorical construct has recently been challenged (Van Os, 2009). The difficulties of schizophrenia and personality research could also be related to the potential overlap in the two disorders. Some studies have suggested this overlap between personality traits and schizophrenia, particularly trait neuroticism (Lönnqvist et al., 2009). This potentially confounds association research, although these studies use personality instruments related to the Five Factor model of normal personality, rather than clinical populations where personality domains may be different (Mulder, Newton-Howes, Crawford, & Tyrer, 2011). Finally, it is possible that schizophrenia researchers are more focused on the biology of the disorder and therefore relatively neglect personality factors, whereas personality researchers often find comorbid non-psychotic disorders and are subsequently less focused on psychosis, leaving this comorbid group relatively under-researched. Whatever the reason, there is a need to gain a clearer understanding on the impact of personality in clinical samples of patients with schizophrenia in order to guide further research and clinical decision making. It is not clear if poor social functioning is due to a presumed poor engagement with treatment that is associated with personality dysfunction generally or comorbidity personality pathology and psychosis. A lack of engagement with service providers is likely to lead to poorer functioning and poor satisfaction with service provision. Alternatively, the psychopathology associated with comorbidity may be the relevant factor. In order to assess this, we analysed a sample of patients with schizophrenia in a standard outpatient setting. The aim of this study was to clarify the degree of social functioning and satisfaction with care in a routine clinical sample of patients with schizophrenia, assessing the impact of personality dysfunction and disorder. We expected personality to negatively impact on both satisfaction and social functioning despite their psychotic mental disorder. The relationship between schizophrenia and personality disorder was assessed to clarify if any correlation was due to the potential for diagnostic confounding.
(2012) DOI: 10.1002/pmh
Personality in schizophrenia
Methodology Sample A survey approach was used to assess the views of patients cared for in adult community mental health services in the Hawke’s Bay, New Zealand, in order to better understand their views of treatment. All patients with disorders severe enough to warrant detention under the Mental Health Act were considered as potential candidates, and a ‘snowball’ approach used to access these patients in the community (King et al., 2003). All patients were therefore under the care of a community psychiatrist at the time of the survey, diagnosed with significant mental disorders and aged between 16 and 65 years. No patient was excluded from the study unless they were too unwell to consent. This study examines those with a diagnosis of schizophrenia. Measures The decisions as to the measures used and demographic variables to collect to aid in diagnosis and quantify outcomes were made in consultation with patient focus groups in order to maximize the acceptability of the research for patients. It was agreed that self-report measures of social functioning, satisfaction with care and psychopathology were most appropriate, as these were related most closely to the patients’ overall well being. The diagnosis of schizophrenia was made on clinical grounds. All diagnoses were made using DSM-IV criteria, and all clinicians were senior psychiatrists. Research comparing clinical-based and instrument-based diagnoses of schizophrenia suggests that reliability in this population is high (Weaver et al., 2003) and DSM is designed to provide diagnostic uniformity (Spitzer, Endicott, & Robins, 1975). Differentiation by sub-type was not undertaken. This was carried out by accessing the clinical notes and confirming the diagnosis from these. The Standardized Assessment of Personality— Abbreviated Scale (SAPAS) (Moran, Leese, &
Copyright © 2012 John Wiley & Sons, Ltd.
Lee, 2003) was used to screen for personality disorder. This tool was initially used in a general psychiatric population in England and later validated in a Dutch outpatient sample (Germans, Van Heck, Moran, & Hodiamont, 2008) when completed by patients. This was both acceptable to patients, was felt to potentially provide a clinically usable tool in day-to-day practice and has a positive predictive value greater than 80% in secondary care samples for a diagnosis of personality disorder with a cut-off score of 3. Two scores were derived from this measure. First, patients who scored 3 and over on the SAPAS were accorded a diagnosis of personality disorder. Second, the total scale on the SAPAS was used to describe personality dysfunction dimensionally with scores ranging from 0 (no personality dysfunction) to 8 (severe personality dysfunction). A dimensional assessment was used alongside the dichotomous definition, as it is likely that iterations of both DSM and ICD will emphasize the dimensional aspects of personality pathology whilst not moving away completely from diagnostic categories. The Client Satisfaction Questionnaire was used in order to measure satisfaction with the care provided by secondary psychiatric services (Atkinson & Zwick, 1982). This is a simple to use 10-question survey tool validated for the use in clients with mental disorders. It is build from a longer questionnaire and has good reliability and validity. The Hopkins Symptoms Checklist— Revised provides a measure of psychopathology and allows for analysis of depressive, anxiety and global psychopathology (Derogatis, 1983). It also provides a measure of psychosis, indicating current symptoms. This measures patients’ subjective experience of a broad range of symptoms on a five-point scale in nine broad domains. A modified scale also included questions to take into account the possibility of manic symptoms. The Social Functioning Questionnaire provided an objective measure of patients’ experiences in the community (Tyrer et al., 2005). This brief tool gives an accurate assessment of patients’ subject experiences of their social function. It has been
(2012) DOI: 10.1002/pmh
Newton-Howes and Marsh
used routinely to assess social function in a psychiatric outpatient setting. Data analysis All data were analysed used SPSS version 19 (SPSS Inc., Chicago, IL, USA). The data were assessed for skewness, and non-parametric statistics were used where this was the case to look for simple correlation between the presence of personality disorder or dysfunction and social functioning and satisfaction with care. Linear regression was used to assess if there was a relationship between social functioning and personality dysfunction, taking into account other axis I disorders and current psychotic phenomena. Finally, partial correlation coefficients were used to assess if worsening personality dysfunction was confounded with a diagnosis of schizophrenia, bearing in mind the research suggesting an overlap in symptoms. This was to ascertain, if possible, whether any relationship between personality and poorer outcome scores could be due to confounding by schizophrenia. Results Demographics Seventy nine patients in total completed the questionnaire with 14 (15%) declining and 1 (1%) lacking the capacity to consent. The demographic data from the study group are shown in Table 1. This identifies the group as predominantly male and of mixed ethnicity with few in employment. Thirty-four per cent fulfilled the criteria for personality disorder. Analysis of the influence of personality dysfunction and disorder was undertaken on the sub-sample of patients with a diagnosis of schizophrenia. Dividing this sub-group into those with a personality disorder compared with those without personality disorder showed no differences as regards the demographic data other than the personality disorder patients being somewhat older as displayed in Table 2.
Copyright © 2012 John Wiley & Sons, Ltd.
Table 1: Demographics for the sample Schizophrenia, n = 46 Sex* Male Female Age, years (SD) Schooling, years (SD) Ethnicity† Maori Pakeha Other Number in employment Carer for children No. with personality disorder{ Mean personality dysfunction{
33 (42%) 13 (17%) 40 (11) 10 (1) 22 (28%) 18 (23%) 2 (3%) 7 (9%) 2 (3%) 27 (34%) 3.3 (2.1)
*Data from one patient missing. Data from eight patients missing. { Data from one patient missing. †
Correlational analysis Item by item analysis of the frequency of positive responses to the individual SAPAS questions is displayed in Table 3 along with inter-item correlations. This shows correlations between questions 1, 2 and 6; 2, 3 and 6; 4 and 6; 5 and 6; and 7 and 8. Of the patients answering three or more SAPAS questions positively indicating the likelihood of personality disorder, 13% answered three positively, 9% answered four positively, 27% answered five positively, 7% answered six positively and 2% answered either seven or all eight questions positively. Fisher’s exact test was used to correlate personality disorder with satisfaction with care and social function. The correlation between depression, anxiety and psychosis was also analysed to examine for the possibility of simple potential confounding. Personality dysfunction was also assessed using Spearman’s Rho to ascertain if this led to a greater degree of statistical certainty between the variables, as the data were skewed. Rank correlations highlighted statistically significant correlations between personality dysfunction, personality disorder and social functioning but not satisfaction with care.
(2012) DOI: 10.1002/pmh
Personality in schizophrenia
Table 2: Demographic data from the schizophrenia sub-sample (n = 45 comparing personality disordered and non-personality disordered patients)* Personality disorder, n = 27
No personality disorder, n = 18
18 (40%) 9 (20%) 43 (11) 16 (2)
14 (31%) 4 (9%) 35 (10) 16 (1)
13 (32%) 10 (24%) 1 (2%) 4 (9%) 1 (%)
9 (22%) 7 (17%) 1 (2%) 3 (7%) 1 (%)
Sex Male Female Age, years (SD) Schooling, years (SD) Ethnicity† Maori Pakeha Other Number in employment No. of people who are carers for children
p 0.323
0.023 0.571 0.621
0.591 0.645
p derived using Fisher’s one-tailed (dichotomous data) test or Spearman’s Rho (means). *Personality data from one schizophrenia patient missing. † Data from four patients missing. Table 3: Item analysis of frequency of SAPAS answers and inter-item correlations No. of PD positive responses
Q.1 Q.2 Q.3 Q.4 Q.5 Q.6 Q.7
Q.1
Q.2
Q.3
Q.4
Q.5
Q.6
Q.7
Q.8
16 (36%)
20 (44%)
24 (53%)
10 (22%)
21 (45.7%)
27 (60%)
16 (36%)
16 (36%)
0.33
0.32 0.46
0.33
0.33 0.40 0.42
Note: Data from 45 patients displayed (one patient missing). Only correlations using Spearman’s Rho that are significant to a p < 0.05 are shown. PD, personality disorder; SAPAS, Standardized Assessment of Personality—Abbreviated Scale.
This correlation was approximately 20% stronger using a dimensional approach. All comorbid mental disorders were correlated with personality problems, however defined. This correlation between personality dysfunction and poorer social functioning in this sample of patients with schizophrenia was therefore potentially confounded by depression, anxiety or diagnostic confounding between the two disorders as partly described previously. It was also unclear if the categorical approach (using a personality disorder diagnosis) or the dimensional
Copyright © 2012 John Wiley & Sons, Ltd.
approach (using a number of positive personality trait problems) was more accurate in identifying if personality problems related to worsening social dysfunction in this sample. Regression analysis To further assess this relationship, linear regression was undertaken to assess if the poor social functioning in this sample correlated with personality dysfunction when other psychopathology, notably
(2012) DOI: 10.1002/pmh
Newton-Howes and Marsh
depression, was taken into account. This was determined a priori to include variable associated with psychopathology. As age was found to be statistically different between the personality disorder and no personality disorder groups, a second regression analysis entering age in block two was also undertaken to assess if this altered the findings. Depression, anxiety, personality and psychotic symptoms were entered into the regression model with social functioning as the dependent variable. As Table 4 shows, the correlation between personality dysfunction and poor social function remained strong (standardized B = 0.65, p = 0.05) even accounting for other clinical variables. Depression also added to the model, separately from personality dysfunction. Psychotic phenomena and anxiety did not predict poorer social functioning. The model accounted for half of the variance predicted (R2 = 0.5). Finally, partial correlation coefficients were generated, looking at the potential confounding between personality and schizophrenia, taking depression and anxiety into account in a stepwise fashion. The correlation between personality dysfunction and schizophrenia was not significant with no other diagnosis considered (p = 0.97), and this remained the case when adding depression (p = 0.80) and depression and anxiety (p = 0.82) into the matrix. As such, the effects of personality in this sample were not accounted for by an overlap with the diagnosis of schizophrenia and were independent of each other. Table 4: Regression analysis of social functioning by diagnosis Variable
B
Personality dysfunction Depression Anxiety Psychosis
0.65 0.31 0.15 0.07
SE 0.32 0.08 0.11 0.06
Beta 0.31 0.80 0.34 0.25
p 0.05 0.01 0.17 0.25
R2 = 0.5. Addition of age to the model (as a factor of difference between the groups) does not significantly alter the Beta or p values above. It was not statistically significantly correlated with a poor Social Functioning Questionnaire.
Copyright © 2012 John Wiley & Sons, Ltd.
Discussion This paper explores, in a small sample of patients with schizophrenia, the potential impact of personality disorder and dysfunction using an easy to use tool to assess personality that is acceptable to patients and applicable in clinical practice. The sample came from a secondary care setting and represents a standard case load in secondary psychiatric services. We were able to demonstrate in this population a clear correlation between personality dysfunction and disorder and poorer social functioning in patients with schizophrenia. Although less statistically robust when using regression modelling to account for other diagnoses, the strength of the correlation remains. Such a finding was not found for satisfaction with care. The association was not accounted for by any potential diagnostic overlap between schizophrenia and personality disorder. The use of the SAPAS for identification of personality problems minimizes the potential for overlap between diagnosis and outcome. This suggests that, in a routine clinical population of patients with clinically diagnosed schizophrenia, personality pathology should not be seen as an impediment to engagement with services and is not likely to lead to poorer satisfaction with care but may be associated with poorer social functioning. This is important as poor social functioning in schizophrenia has long been seen as a major problem, and this has generally been considered to be due to cognitive problems related to schizophrenic psychopathology as opposed to personality difficulties (Brune, Dimaggio, & Lysaker, 2011). Despite intensive study, the outcomes for improving social functioning in this group of patients remain modest at best. It is possible that one of the reasons for this is due to the as yet poorly recognized impact of personality pathology. This highlights an area where further investigation and intervention may be warranted. Certainly, there is an increasing evidence base for successful interventions in patients with personality disorder (Newton-Howes & Davidson, 2009), but much of
(2012) DOI: 10.1002/pmh
Personality in schizophrenia
this research excludes patients with major psychotic disorders. It is not clear at the present time if interventions directed at personality pathology in other groups would translate into this group, but it is an area that warrants further research. Similarly, there is a suggestion from this research that the routine use of the SAPAS in clinical practice may highlight those psychotic patients at greater risk of social dysfunction as a group that warrants closer clinical management. In this group, 39% of patients with a SAPAS positive for personality disorder answered five or more questions in the affirmative, suggesting a relatively significant burden in terms of personality pathology in this group. It also suggests further research considering personality by severity, rather than by category, may be of interest. As with all studies, the design of this study and some of the practical issues of its implementation limit its utility. The recruitment into the study ultimately leads to smaller than expected numbers, and the lack of previous research made estimating the number of patients required to ensure statistically robust results impossible. Second, the use of a standard clinical sample did not allow for patients to be excluded with other major problems (for example homelessness, poor family support and comorbid addictions problems) and premorbid personality status was unknown, although this design increases the generalizable nature of the research findings. Questions can be raised over the use of the SAPAS to identify personality problems, although there is evidence that this tool has reasonable predictive validity and was deemed acceptable to patients during the study’s development. Equally, the lack of a standardized measure for the diagnosis of schizophrenia could be seen as a weakness, although this is a robust clinical diagnosis and all psychiatrists in the catchment area under study use DSM-IV criteria, minimizing the probability of heterogeneity in the sample. Equally, this approach identifies a clinical sample of patients with schizophrenia, increasing the applicability of the findings to a clinical sample and the utility of these findings in day-to-day
Copyright © 2012 John Wiley & Sons, Ltd.
clinical practice. Finally, the use of self-report measure may limit the findings; however, these were rapid to use, acceptable to patients and potentially able to be incorporated into clinical practice, potentially identifying tools that may aid the translation of research into practice, a major problem in psychiatry (Proctor et al., 2009). Despite these limitations, this study highlights an area that is relatively under-researched, and on the basis of these, finding warrants further investigation. Using a longitudinal design would potentially allow for premorbid or personality change to be assessed, not as yet studied. Clearer description of the relationship between personality disorder and schizophrenia in terms of the impact in patients lives will allow for thoughtful interventions to be developed and trailed and may help in improving the outcomes in this group of patients. Acknowledgement A grant was provided by the Hawkes Bay Medical Research Council. References Atkinson, C., & Zwick, R. (1982). The client satisfaction questionnaire: Psychometric properties and correlations with service utilization and psychotherapy outcome. Evaluation and Programme Planning, 5(3), 233–237. Bernstein, D., Iscan, C., & Maser, J. (2007). Opinions of personality disorder experts regarding the DSM-IV Personality Disorders Classification System. Journal of Personality Disorders, 21, 536–551. Bieling, P., Green, S., & Macqueen, G. (2007). The impact of personality disorders on treatment outcome in bipolar disorder: A review. Personality and Mental Health, 1, 2–13. Brune, M., Dimaggio, G., & Lysaker, P. (2011). Metacognition and social functioning in schizophrenia: Evidence, mechanisms of influence and treatment implications. Current Psychiatry Reviews, 7, 239–247. Derogatis, L. R. (1983). The SLR-90-R manual II: Administration, scoring, and procedures. Towson, MD: Clinical Psychometric Research. Germans, S., Van Heck, G., Moran, P., & Hodiamont, P. (2008). The Self-report Standardized Assessment of Personality—Abbreviated Scale: Preliminary results of a
(2012) DOI: 10.1002/pmh
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brief screening test for personality disorders. Journal of Personality and Mental Health, 2, 70–76. Harned, M., Rizvi, S., & Linehan, M. (2010). Impact of co-occurring posttraumatic stress disorder on suicidal women with borderline personality disorder. The American Journal of Psychiatry, 167, 1210–1217. Kentros, M., Smith, T., Hull, J., McKee, M., Terkelsen, K., & Capalbo C. (1997). Stability of personality traits in schizophrenia and schizoaffective disorder: A pilot project. Journal of Nervous and Mental Diseases, 185, 549–555. King, M., McKeown, E., Warner, J., Ramsey, A., Johnson, K., Cort, C., Wright, L, & Blizard, R. (2003). Mental health and quality of life of gay men and lesbians in England and Wales: Controlled, cross-sectional study. The British Journal of Psychiatry, 183, 552–558. Livesley, J. (2011). An empirically-based classification of personality disorder. Journal of Personality Disorder, 25, 397–420. Lönnqvist, J.E., Verkasalo, M., Haukka, J., Nyman, K., Tihonen, J., Laaksonen, I., Leskinen, J., Lönnqvist, J., & Henriksson, M. (2009). Premorbid personality factors in schizophrenia and bipolar disorder: Results from a large cohort study of male conscripts. Journal of Abnormal Psychology, 118, 418–423. Moran, P., Leese, M., & Lee, T. (2003). Standardised Assessment of Personality—Abbreviated Scale (SAPAS): Preliminary validation of a brief screen for personality disorder. The British Journal of Psychiatry, 183, 228–232. Mulder, R. (2002). Personality pathology and treatment outcome in major depression: A review. The American Journal of Psychiatry, 159, 359–371. Mulder, R., Newton-Howes, G., Crawford, M., & Tyrer, P. (2011). The central domains of personality pathology in psychiatric patients. Journal of Personality Disorder, 25, 364–377. Newton-Howes, G., & Davidson, K. (2009). The New Oxford Textbook of Psychiatry (ch. 4.12.7). In Management of personality disorders. Oxford: Oxford University Press. Newton-Howes, G., Tyrer, P., & Johnson, T. (2006). Personality disorder and the outcome of depression: A meta-analysis of published studies. The British Journal of Psychiatry, 188, 13–20. Newton-Howes, G., Tyrer, P., Moore, A., & Nur, U. (2007). Personality disorder and outcome in schizophrenia: A negative systematic review. Personality and Mental Health, 1, 22–26. Newton-Howes, G., Tyrer, P., & Weaver, T. (2010). The prevalence of personality disorder, its comorbidity with mental state disorders, and its clinical significance in community mental health teams. Social Psychiatry and Psychiatric Epidemiology, 45, 453–457. Newton-Howes, G., Tyrer, P., Yang, M., & North, B. (2008). The prevalence of personality disorder in schizophrenia: Rates and explanatory modelling. Psychological Medicine, 37, 1–8.
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Proctor, E., Landsverk, J., Aarons, G., Chambers, D., Glisson, C., & Mittman, B. (2009). Implementation research in mental health services: An emerging science with conceptual, methodological, and training challenges. Administration and Policy in Mental Health, 36, 24–34. Samuel, D., & Widiger, T. (2011). Clinicians’ use of personality disorder models within a particular treatment setting: A longitudinal comparison of temporal consistency and clinical utility. Personality and Mental Health, 5, 12–28. Shea, M., Stout, R., Yen, S., Pagano, M., Skodol, A., Morley, L., Gunderson, J., McGlashan, T., Grilo, C., Sanislow, C., Bender, D., & Zanarini, M. (2004). Associations in the course of personality disorders and Axis I disorders over time. Journal of Abnormal Psychology, 113, 499–508. Snowden, P., & Kane, E. (2003). Personality disorder: No longer a diagnosis of exclusion. The Psychiatrist, 27, 401–403. Spitzer, R., Endicott, J., & Robins, E. (1975). Clinical criteria for psychiatric research. The American Journal of Psychiatry, 132, 1187–1192. Tyrer, P., Crawford, M., Mulder, R., Blashfield, R., Farnam, A., Fossati, A., Kim, Y.-R., Koldobsky, N., Lecic-Tosevski, D., Ndetei, D., Swales, M., Clark, L.A., Reed, G.M. (2011). The rationale for the reclassification of personality disorder in the 11th revision of the International Classification of Diseases (ICD-11). Personality and Mental Health, 5, 246–259. Tyrer, P., Nur, U., Crawford, M., Karlsen, S., MacLean, C., Rao, B., & Johnson, T. (2005). The Social Functioning Questionnaire: A rapid and robust measure of perceived functioning. The International Journal of Social Psychiatry, 51(3), 265–282. Van Os, J. (2009). A salience dysregulartion syndrome. BJP, 194, 101–103. Walter, M., Gunderson, J. G., Zanarini, M. C., Sanislow, C. A., Grilo, C. M., McGlashan, T. H., Morey, L. C., Yen, S., Stout, R. L., & Skodol, A. E. (2009). New onsets of substance use disorders in borderline personality disorder over 7 years of follow-ups: Findings from the Collaborative Longitudinal Personality Disorders Study. Addiction, 104(1), 97–103. Weaver, T., Madden, P., Charles, V., Stimson, G., Renton, A., Tyrer, P., Barnes, T., Bench, C., Middleton, N., Wright, S., Patterson, W., Shanahan, N., Seivewright, N., & Ford, C. (2003). Comorbidity of substance misuse and mental illness in community mental health teams and substance misuse services. The British Journal of Psychiatry, 183, 304–313.
Address correspondence to: Giles Newton-Howes, 76 Wellesley Road, Hawke’s Bay DHB, Napier, New Zealand. Email: [email protected]
(2012) DOI: 10.1002/pmh
Personality dysfunction and social functioning in schizophrenia
GILES NEWTON-HOWES1,2,3,4 AND REGINALD MARSH, 1Hawkes Bay DHB, Napier, New Zealand; 2 Imperial College, London, UK; 3Wellington School of Medicine, Otago University, New Zealand; 4 Auckland University School of Medicine, c/- 76 Wellesley Road, Napier South, Napier, New Zealand ABSTRACT Aim – To determine if personality dysfunction is associated with poorer clinical and social indicators in patients with schizophrenia. Methodology – An observational study of patients with schizophrenia in psychiatric care assessed patient satisfaction with care, social functioning and psychopathology. Analysis of the relationship between personality and these three domains quantitatively assessed differences between patients with and without comorbid personality dysfunction. Diagnostic confounding was assessed using partial correlation coefficients. Results – Forty-five patients with schizophrenia were studied. In the schizophrenia group, personality dysfunction correlated with poorer social functioning but not poorer satisfaction with care. Linear regression found that the relationship between poorer social functioning and personality disorder in schizophrenia remained, taking other diagnoses and age into account. Partial correlation coefficients confirmed that this was no related to an overlap between personality and schizophrenia symptoms in this sample. Conclusion – Personality dysfunction may negatively influence social functioning in patients with schizophrenia but does not appear to impact on patients’ views of the care they receive. This is not due to the potential for diagnostic confounding between schizophrenia and personality disorder. Further research using larger samples is needed to confirm this association. Copyright © 2012 John Wiley & Sons, Ltd. Introduction There is a growing interest in understanding the impact of personality in axis I disorders, and this interest has led to a growing understanding of the potential impact of personality in disorders such as depression (Mulder, 2002; Newton-Howes, Tyrer, & Johnson, 2006), bipolar affective disorder (Bieling, Green, & Macqueen, 2007), substance use disorders (Walter et al., 2009) and anxiety disorders (Harned, Rizvi, & Linehan, 2010; Newton-Howes, Tyrer, & Weaver, 2010). Recently, longitudinal personality disorder studies have reported on the
Copyright © 2012 John Wiley & Sons, Ltd.
impact of personality in multiple axis I disorders (Shea et al., 2004) and suggest that personality disorder negatively impacts on many of the major mental disorders. This identifies personality as a focus of attention considering management options and is no longer a ‘diagnosis of exclusion’ (Snowden & Kane, 2003). It may also explain in some part why many interventions in patients with these axis I disorders are partly responsive to treatment, remaining deficits being related to the personality component of their presentation rather than the axis I disorder. What is notable about this body of literature is the relative absence of data on personality
(2012) DOI: 10.1002/pmh
Newton-Howes and Marsh
function in patients with schizophrenia, despite the fact that this mental disorder affects as much as 1% of the population and is associated with poor symptomatic and functional outcomes. Even the prevalence of personality disorder in schizophrenia is poorly characterized (Newton-Howes, Tyrer, Yang, & North, 2008), and reviews of the literature have failed to find longitudinal papers that report on the outcomes in patients with schizophrenia and comorbid personality disorder (Newton-Howes, Tyrer, Moore, & Nur, 2007). The reasons for this are unclear but may be due to the conceptual difficulties with the personality disorder construct. Surveys of personality disorder experts find that even this group has a negative view of the current DSM conceptualization of personality pathology (Bernstein et al., 2007), although there is widespread disagreement about how to better categorize the construct. There are strong arguments for a dimensional approach to characterizing personality, although this may prove difficult to use in everyday clinical settings; there is evidence that it could improve utility of diagnosis (Samuel & Widiger, 2011). Certainly, the research into what these dimensions might be and the second order facets involved is highly complex (Livesley, 2011) and would probably greatly reduce clinical utility for the practicing psychiatrist. Others advocate a general approach to a diagnosis of personality disorder, preferring a clinically oriented severity measure with subsequent trait domains (Tyrer P, Crawford M, Mulder R. et al., 2011). These diagnostic issues are also raised by prominent schizophrenia researchers (Van Os, 2009), although schizophrenia as a clinical entity is well developed and routinely used in clinical practice, a statement that is not generally true of personality disorder. Despite these diagnostic issues, studies suggest that personality can be reliably tested in patients with schizophrenia by using a test–retest methodology (Kentros et al., 1997) and this problem is one that rests with all personality research. Such conceptual difficulties have also been raised with the diagnosis of schizophrenia and schizophrenia research, where the current
Copyright © 2012 John Wiley & Sons, Ltd.
categorical construct has recently been challenged (Van Os, 2009). The difficulties of schizophrenia and personality research could also be related to the potential overlap in the two disorders. Some studies have suggested this overlap between personality traits and schizophrenia, particularly trait neuroticism (Lönnqvist et al., 2009). This potentially confounds association research, although these studies use personality instruments related to the Five Factor model of normal personality, rather than clinical populations where personality domains may be different (Mulder, Newton-Howes, Crawford, & Tyrer, 2011). Finally, it is possible that schizophrenia researchers are more focused on the biology of the disorder and therefore relatively neglect personality factors, whereas personality researchers often find comorbid non-psychotic disorders and are subsequently less focused on psychosis, leaving this comorbid group relatively under-researched. Whatever the reason, there is a need to gain a clearer understanding on the impact of personality in clinical samples of patients with schizophrenia in order to guide further research and clinical decision making. It is not clear if poor social functioning is due to a presumed poor engagement with treatment that is associated with personality dysfunction generally or comorbidity personality pathology and psychosis. A lack of engagement with service providers is likely to lead to poorer functioning and poor satisfaction with service provision. Alternatively, the psychopathology associated with comorbidity may be the relevant factor. In order to assess this, we analysed a sample of patients with schizophrenia in a standard outpatient setting. The aim of this study was to clarify the degree of social functioning and satisfaction with care in a routine clinical sample of patients with schizophrenia, assessing the impact of personality dysfunction and disorder. We expected personality to negatively impact on both satisfaction and social functioning despite their psychotic mental disorder. The relationship between schizophrenia and personality disorder was assessed to clarify if any correlation was due to the potential for diagnostic confounding.
(2012) DOI: 10.1002/pmh
Personality in schizophrenia
Methodology Sample A survey approach was used to assess the views of patients cared for in adult community mental health services in the Hawke’s Bay, New Zealand, in order to better understand their views of treatment. All patients with disorders severe enough to warrant detention under the Mental Health Act were considered as potential candidates, and a ‘snowball’ approach used to access these patients in the community (King et al., 2003). All patients were therefore under the care of a community psychiatrist at the time of the survey, diagnosed with significant mental disorders and aged between 16 and 65 years. No patient was excluded from the study unless they were too unwell to consent. This study examines those with a diagnosis of schizophrenia. Measures The decisions as to the measures used and demographic variables to collect to aid in diagnosis and quantify outcomes were made in consultation with patient focus groups in order to maximize the acceptability of the research for patients. It was agreed that self-report measures of social functioning, satisfaction with care and psychopathology were most appropriate, as these were related most closely to the patients’ overall well being. The diagnosis of schizophrenia was made on clinical grounds. All diagnoses were made using DSM-IV criteria, and all clinicians were senior psychiatrists. Research comparing clinical-based and instrument-based diagnoses of schizophrenia suggests that reliability in this population is high (Weaver et al., 2003) and DSM is designed to provide diagnostic uniformity (Spitzer, Endicott, & Robins, 1975). Differentiation by sub-type was not undertaken. This was carried out by accessing the clinical notes and confirming the diagnosis from these. The Standardized Assessment of Personality— Abbreviated Scale (SAPAS) (Moran, Leese, &
Copyright © 2012 John Wiley & Sons, Ltd.
Lee, 2003) was used to screen for personality disorder. This tool was initially used in a general psychiatric population in England and later validated in a Dutch outpatient sample (Germans, Van Heck, Moran, & Hodiamont, 2008) when completed by patients. This was both acceptable to patients, was felt to potentially provide a clinically usable tool in day-to-day practice and has a positive predictive value greater than 80% in secondary care samples for a diagnosis of personality disorder with a cut-off score of 3. Two scores were derived from this measure. First, patients who scored 3 and over on the SAPAS were accorded a diagnosis of personality disorder. Second, the total scale on the SAPAS was used to describe personality dysfunction dimensionally with scores ranging from 0 (no personality dysfunction) to 8 (severe personality dysfunction). A dimensional assessment was used alongside the dichotomous definition, as it is likely that iterations of both DSM and ICD will emphasize the dimensional aspects of personality pathology whilst not moving away completely from diagnostic categories. The Client Satisfaction Questionnaire was used in order to measure satisfaction with the care provided by secondary psychiatric services (Atkinson & Zwick, 1982). This is a simple to use 10-question survey tool validated for the use in clients with mental disorders. It is build from a longer questionnaire and has good reliability and validity. The Hopkins Symptoms Checklist— Revised provides a measure of psychopathology and allows for analysis of depressive, anxiety and global psychopathology (Derogatis, 1983). It also provides a measure of psychosis, indicating current symptoms. This measures patients’ subjective experience of a broad range of symptoms on a five-point scale in nine broad domains. A modified scale also included questions to take into account the possibility of manic symptoms. The Social Functioning Questionnaire provided an objective measure of patients’ experiences in the community (Tyrer et al., 2005). This brief tool gives an accurate assessment of patients’ subject experiences of their social function. It has been
(2012) DOI: 10.1002/pmh
Newton-Howes and Marsh
used routinely to assess social function in a psychiatric outpatient setting. Data analysis All data were analysed used SPSS version 19 (SPSS Inc., Chicago, IL, USA). The data were assessed for skewness, and non-parametric statistics were used where this was the case to look for simple correlation between the presence of personality disorder or dysfunction and social functioning and satisfaction with care. Linear regression was used to assess if there was a relationship between social functioning and personality dysfunction, taking into account other axis I disorders and current psychotic phenomena. Finally, partial correlation coefficients were used to assess if worsening personality dysfunction was confounded with a diagnosis of schizophrenia, bearing in mind the research suggesting an overlap in symptoms. This was to ascertain, if possible, whether any relationship between personality and poorer outcome scores could be due to confounding by schizophrenia. Results Demographics Seventy nine patients in total completed the questionnaire with 14 (15%) declining and 1 (1%) lacking the capacity to consent. The demographic data from the study group are shown in Table 1. This identifies the group as predominantly male and of mixed ethnicity with few in employment. Thirty-four per cent fulfilled the criteria for personality disorder. Analysis of the influence of personality dysfunction and disorder was undertaken on the sub-sample of patients with a diagnosis of schizophrenia. Dividing this sub-group into those with a personality disorder compared with those without personality disorder showed no differences as regards the demographic data other than the personality disorder patients being somewhat older as displayed in Table 2.
Copyright © 2012 John Wiley & Sons, Ltd.
Table 1: Demographics for the sample Schizophrenia, n = 46 Sex* Male Female Age, years (SD) Schooling, years (SD) Ethnicity† Maori Pakeha Other Number in employment Carer for children No. with personality disorder{ Mean personality dysfunction{
33 (42%) 13 (17%) 40 (11) 10 (1) 22 (28%) 18 (23%) 2 (3%) 7 (9%) 2 (3%) 27 (34%) 3.3 (2.1)
*Data from one patient missing. Data from eight patients missing. { Data from one patient missing. †
Correlational analysis Item by item analysis of the frequency of positive responses to the individual SAPAS questions is displayed in Table 3 along with inter-item correlations. This shows correlations between questions 1, 2 and 6; 2, 3 and 6; 4 and 6; 5 and 6; and 7 and 8. Of the patients answering three or more SAPAS questions positively indicating the likelihood of personality disorder, 13% answered three positively, 9% answered four positively, 27% answered five positively, 7% answered six positively and 2% answered either seven or all eight questions positively. Fisher’s exact test was used to correlate personality disorder with satisfaction with care and social function. The correlation between depression, anxiety and psychosis was also analysed to examine for the possibility of simple potential confounding. Personality dysfunction was also assessed using Spearman’s Rho to ascertain if this led to a greater degree of statistical certainty between the variables, as the data were skewed. Rank correlations highlighted statistically significant correlations between personality dysfunction, personality disorder and social functioning but not satisfaction with care.
(2012) DOI: 10.1002/pmh
Personality in schizophrenia
Table 2: Demographic data from the schizophrenia sub-sample (n = 45 comparing personality disordered and non-personality disordered patients)* Personality disorder, n = 27
No personality disorder, n = 18
18 (40%) 9 (20%) 43 (11) 16 (2)
14 (31%) 4 (9%) 35 (10) 16 (1)
13 (32%) 10 (24%) 1 (2%) 4 (9%) 1 (%)
9 (22%) 7 (17%) 1 (2%) 3 (7%) 1 (%)
Sex Male Female Age, years (SD) Schooling, years (SD) Ethnicity† Maori Pakeha Other Number in employment No. of people who are carers for children
p 0.323
0.023 0.571 0.621
0.591 0.645
p derived using Fisher’s one-tailed (dichotomous data) test or Spearman’s Rho (means). *Personality data from one schizophrenia patient missing. † Data from four patients missing. Table 3: Item analysis of frequency of SAPAS answers and inter-item correlations No. of PD positive responses
Q.1 Q.2 Q.3 Q.4 Q.5 Q.6 Q.7
Q.1
Q.2
Q.3
Q.4
Q.5
Q.6
Q.7
Q.8
16 (36%)
20 (44%)
24 (53%)
10 (22%)
21 (45.7%)
27 (60%)
16 (36%)
16 (36%)
0.33
0.32 0.46
0.33
0.33 0.40 0.42
Note: Data from 45 patients displayed (one patient missing). Only correlations using Spearman’s Rho that are significant to a p < 0.05 are shown. PD, personality disorder; SAPAS, Standardized Assessment of Personality—Abbreviated Scale.
This correlation was approximately 20% stronger using a dimensional approach. All comorbid mental disorders were correlated with personality problems, however defined. This correlation between personality dysfunction and poorer social functioning in this sample of patients with schizophrenia was therefore potentially confounded by depression, anxiety or diagnostic confounding between the two disorders as partly described previously. It was also unclear if the categorical approach (using a personality disorder diagnosis) or the dimensional
Copyright © 2012 John Wiley & Sons, Ltd.
approach (using a number of positive personality trait problems) was more accurate in identifying if personality problems related to worsening social dysfunction in this sample. Regression analysis To further assess this relationship, linear regression was undertaken to assess if the poor social functioning in this sample correlated with personality dysfunction when other psychopathology, notably
(2012) DOI: 10.1002/pmh
Newton-Howes and Marsh
depression, was taken into account. This was determined a priori to include variable associated with psychopathology. As age was found to be statistically different between the personality disorder and no personality disorder groups, a second regression analysis entering age in block two was also undertaken to assess if this altered the findings. Depression, anxiety, personality and psychotic symptoms were entered into the regression model with social functioning as the dependent variable. As Table 4 shows, the correlation between personality dysfunction and poor social function remained strong (standardized B = 0.65, p = 0.05) even accounting for other clinical variables. Depression also added to the model, separately from personality dysfunction. Psychotic phenomena and anxiety did not predict poorer social functioning. The model accounted for half of the variance predicted (R2 = 0.5). Finally, partial correlation coefficients were generated, looking at the potential confounding between personality and schizophrenia, taking depression and anxiety into account in a stepwise fashion. The correlation between personality dysfunction and schizophrenia was not significant with no other diagnosis considered (p = 0.97), and this remained the case when adding depression (p = 0.80) and depression and anxiety (p = 0.82) into the matrix. As such, the effects of personality in this sample were not accounted for by an overlap with the diagnosis of schizophrenia and were independent of each other. Table 4: Regression analysis of social functioning by diagnosis Variable
B
Personality dysfunction Depression Anxiety Psychosis
0.65 0.31 0.15 0.07
SE 0.32 0.08 0.11 0.06
Beta 0.31 0.80 0.34 0.25
p 0.05 0.01 0.17 0.25
R2 = 0.5. Addition of age to the model (as a factor of difference between the groups) does not significantly alter the Beta or p values above. It was not statistically significantly correlated with a poor Social Functioning Questionnaire.
Copyright © 2012 John Wiley & Sons, Ltd.
Discussion This paper explores, in a small sample of patients with schizophrenia, the potential impact of personality disorder and dysfunction using an easy to use tool to assess personality that is acceptable to patients and applicable in clinical practice. The sample came from a secondary care setting and represents a standard case load in secondary psychiatric services. We were able to demonstrate in this population a clear correlation between personality dysfunction and disorder and poorer social functioning in patients with schizophrenia. Although less statistically robust when using regression modelling to account for other diagnoses, the strength of the correlation remains. Such a finding was not found for satisfaction with care. The association was not accounted for by any potential diagnostic overlap between schizophrenia and personality disorder. The use of the SAPAS for identification of personality problems minimizes the potential for overlap between diagnosis and outcome. This suggests that, in a routine clinical population of patients with clinically diagnosed schizophrenia, personality pathology should not be seen as an impediment to engagement with services and is not likely to lead to poorer satisfaction with care but may be associated with poorer social functioning. This is important as poor social functioning in schizophrenia has long been seen as a major problem, and this has generally been considered to be due to cognitive problems related to schizophrenic psychopathology as opposed to personality difficulties (Brune, Dimaggio, & Lysaker, 2011). Despite intensive study, the outcomes for improving social functioning in this group of patients remain modest at best. It is possible that one of the reasons for this is due to the as yet poorly recognized impact of personality pathology. This highlights an area where further investigation and intervention may be warranted. Certainly, there is an increasing evidence base for successful interventions in patients with personality disorder (Newton-Howes & Davidson, 2009), but much of
(2012) DOI: 10.1002/pmh
Personality in schizophrenia
this research excludes patients with major psychotic disorders. It is not clear at the present time if interventions directed at personality pathology in other groups would translate into this group, but it is an area that warrants further research. Similarly, there is a suggestion from this research that the routine use of the SAPAS in clinical practice may highlight those psychotic patients at greater risk of social dysfunction as a group that warrants closer clinical management. In this group, 39% of patients with a SAPAS positive for personality disorder answered five or more questions in the affirmative, suggesting a relatively significant burden in terms of personality pathology in this group. It also suggests further research considering personality by severity, rather than by category, may be of interest. As with all studies, the design of this study and some of the practical issues of its implementation limit its utility. The recruitment into the study ultimately leads to smaller than expected numbers, and the lack of previous research made estimating the number of patients required to ensure statistically robust results impossible. Second, the use of a standard clinical sample did not allow for patients to be excluded with other major problems (for example homelessness, poor family support and comorbid addictions problems) and premorbid personality status was unknown, although this design increases the generalizable nature of the research findings. Questions can be raised over the use of the SAPAS to identify personality problems, although there is evidence that this tool has reasonable predictive validity and was deemed acceptable to patients during the study’s development. Equally, the lack of a standardized measure for the diagnosis of schizophrenia could be seen as a weakness, although this is a robust clinical diagnosis and all psychiatrists in the catchment area under study use DSM-IV criteria, minimizing the probability of heterogeneity in the sample. Equally, this approach identifies a clinical sample of patients with schizophrenia, increasing the applicability of the findings to a clinical sample and the utility of these findings in day-to-day
Copyright © 2012 John Wiley & Sons, Ltd.
clinical practice. Finally, the use of self-report measure may limit the findings; however, these were rapid to use, acceptable to patients and potentially able to be incorporated into clinical practice, potentially identifying tools that may aid the translation of research into practice, a major problem in psychiatry (Proctor et al., 2009). Despite these limitations, this study highlights an area that is relatively under-researched, and on the basis of these, finding warrants further investigation. Using a longitudinal design would potentially allow for premorbid or personality change to be assessed, not as yet studied. Clearer description of the relationship between personality disorder and schizophrenia in terms of the impact in patients lives will allow for thoughtful interventions to be developed and trailed and may help in improving the outcomes in this group of patients. Acknowledgement A grant was provided by the Hawkes Bay Medical Research Council. References Atkinson, C., & Zwick, R. (1982). The client satisfaction questionnaire: Psychometric properties and correlations with service utilization and psychotherapy outcome. Evaluation and Programme Planning, 5(3), 233–237. Bernstein, D., Iscan, C., & Maser, J. (2007). Opinions of personality disorder experts regarding the DSM-IV Personality Disorders Classification System. Journal of Personality Disorders, 21, 536–551. Bieling, P., Green, S., & Macqueen, G. (2007). The impact of personality disorders on treatment outcome in bipolar disorder: A review. Personality and Mental Health, 1, 2–13. Brune, M., Dimaggio, G., & Lysaker, P. (2011). Metacognition and social functioning in schizophrenia: Evidence, mechanisms of influence and treatment implications. Current Psychiatry Reviews, 7, 239–247. Derogatis, L. R. (1983). The SLR-90-R manual II: Administration, scoring, and procedures. Towson, MD: Clinical Psychometric Research. Germans, S., Van Heck, G., Moran, P., & Hodiamont, P. (2008). The Self-report Standardized Assessment of Personality—Abbreviated Scale: Preliminary results of a
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Address correspondence to: Giles Newton-Howes, 76 Wellesley Road, Hawke’s Bay DHB, Napier, New Zealand. Email: [email protected]
(2012) DOI: 10.1002/pmh
