482
ANZJP Correspondence
dimensions will complicate trials examining the effects considerably. An alternative solution would be to retain a threshold for the disorders, but combine this with a dimensional approach. So, patients would still receive one or more diagnoses for common mental disorders, but at the same time the most important dimensions can be assessed. This may lead to a more precise diagnosis and more focused interventions, while retaining the advantages of the categorical model. A purely dimensional approach is probably better empirically, but a combined dimensional and categorical approach may be more practical and feasible in the current health care systems. The combined dimensional and categorical approach that was included in the DSM-5 for
personality disorders is a good example of how this could be done in the ICD-11 for the common mental disorders. It is a pity that the dimensional approach in addition or as an alternative to the current categorical approach was not pushed forward in the DSM-5. The ICD-11 offers a new opportunity, and I am sure we all hope that this is not also squandered.
Mental illness and the National Disability Insurance Scheme: Lessons from Europe Luis Salvador-Carulla1,2 and Stewart Einfeld1,2
elderly individuals. Others, such as the Dutch system, were developed in the early 1990s and incorporated mental illness from its onset. In Germany, the main focus was on physical disabilities and did not include mental illness and dementia until 2008. The accumulated wealth of information on the implementation of disability schemes in Europe has been partly overlooked in the development of the NDIS. In addition to the general recommendations made by Williams and Smith, there are practical issues that deserve further analysis such as the contextualisation of the care system, the case identification, the economics of disability, and training in disability care and management.
1Centre
for Disability Research and Policy, University of Sydney, Sydney, Australia 2Brain and Mind Research Institute, University of Sydney, Sydney, Australia Corresponding author: Luis Salvador-Carulla, T424 Cumberland Campus, The University of Sydney, 75 East Street, Lidcombe, NSW 2141, Australia. Email: [email protected] DOI: 10.1177/0004867414531833
Williams and Smith (2014) and Duffy and Williams (2012) discuss a number of pertinent issues regarding implementation of the National Disability Insurance Scheme (NDIS), particularly in light of European experience. The majority of disability systems in Western Europe followed the Recommendation of the European Council in 1998, which was mainly intended to provide support for
Funding This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.
Declaration of interest The author reports no conflicts of interest. The author alone is responsible for the content and writing of the paper.
Context of care Local care systems vary and this leads to very different effects of budgets on outcomes in different countries (Arntz and Thomsen, 2011). Unfortunately, there is a limited number of comparisons of the mental health system in Australia with other countries, and comparisons of the social care system are virtually
References Cuijpers P, De Graaf R and Van Dorsselaer S (2004) Minor depression: risk profiles, functional disability, health care use and risk of developing major depression. Journal of Affective Disorders 79: 71–79. Cuijpers P, Vogelzangs N, Twisk J, et al. (2013) Differential mortality rates in major and subthreshold depression? A meta-analysis of studies that measured both. British Journal of Psychiatry 202: 22–27. Okasha A (2009) Would the use of dimensions instead of categories remove problems related to subthreshold disorders? European Archives of Psychiatry and Clinical Neuroscience 259 (Suppl 2): S129–S133. Widiger TA and Samuel DB (2005) Diagnostic categories or dimensions? A question for the Diagnostic and statistical manual of mental disorders-fifth edition. Journal of Abnormal Psychology 114: 494–504. Watson D (2005) Rethinking the mood and anxiety disorders: A quantitative hierarchical model for DSM-V. Journal of Abnormal Psychology 114: 522–536.
non-existent. As an example, to understand the outcomes of individual budgets in England and Australia it is important to consider that our national system is probably more fragmented and has lower levels of integrated care across sectors. The lack of strong coordination between the social and the health sectors, and the disability and the elderly care sectors have been identified as major problems in the implementation of disability programs in Europe. On the other hand, social and health care systems show large differences within Australia. For example, community care and accommodation support in Victoria was nearly double that of New South Wales (NSW) in 2011 (Australian Institute of Health and Welfare (AIHW), 2012). In the AIHW report, the primary disability groups included 1401 cases with psychiatric disorders in NSW and 14,305 cases in Victoria. These differences point to future disparities in the implementation of the NDIS. Previous experiences in Europe indicate that listing local services by their names may not provide the information required for policy
Australian & New Zealand Journal of Psychiatry, 48(5) Downloaded from anp.sagepub.com at NANYANG TECH UNIV LIBRARY on June 2, 2015
483
ANZJP Correspondence analysis. The 2003 Eurostat report concluded that the statistics concerning formal support were not comparable across European countries due to problems of terminology and definitions (Eurostat, 2003). In 2011, a classification system for coding and mapping long-term care services was released to allow for comparison across European countries (SalvadorCarulla et al., 2013). Similarly, there is a need for standard mapping of mental health interventions and packages of care to improve benchmarking, case management and navigation in the care system.
Identification of cases of disability in severe mental illness The assessment of disability in mental illness is more complex than in any other disability group due to the difficulty of differentiating symptoms from functional impairment (Wakefield, 2009), and in establishing subtypes of disabilities based on severity levels. In 2010, Germany had to revise its eligibility criteria for mental illness (Büscher et al., 2011). In Spain, a report recommended a complementary evaluation and incorporation of tools for casemix and risk pooling and stratification. The report recommended including the level of global functioning, social characteristics (persons with severe mental illness (SMI) living alone, and working/studying), course of illness and services needed on a long-term basis (Ochoa et al., 2012). The Spanish disability scheme opted for a common evaluation system for all disabilities in 2007, and the consequent problems in the eligibility system for SMI required its revision in 2014. The under-reporting of the rates of the ‘profound’ and ‘severe’ categories in the Australian Survey of Mental Health and Wellbeing (Australian Bureau of Statistics, 2010) indicate that similar problems may appear in the identification of SMI in the NDIS in comparison with other disability groups.
Economics of disability A miscalculation in the costs of the various disability schemes has been reported in several European countries after their implementation. Spending on disability support services in Australia increased by 2% to $6.2 billion between 2009/10 and 2010/11 (AIHW, 2012), and a further increase is expected after the implementation of NDIS. A detailed analysis of the cost and financing of disability schemes in other countries may help to design alternative scenarios which are relevant, particularly for complex conditions such as SMI. The field of ‘disability economics’ is in its infancy and there has been an insufficient knowledge transfer from health economics and financing. This has relevant implications for planning disability care. Basic information on the units of cost in the social care sector is missing and it is necessary to design and cost combined packages of care of social and health interventions for SMI with severe disability under the scheme. In addition, tools used in health economics may require significant changes to be applied in disability economics. As an example, disability-adjusted life years (DALYs) is a measure derived from the Global Burden of Disease Study (GBS), which is routinely used in health policy (Whiteford et al., 2013). However, the concept of ‘disability’ in GBS (‘any short-term or long-term health loss’) is too broad to estimate the burden and related costs of groups with severe impairment in the disability scheme. The analysis of financing of disability also deserves more attention. It is essential to identify the financial flows, their incentives and barriers, and the tentative cost-shifting across different sectors, including health, social, housing, employment, education and criminal justice.
Training Another lesson from the development of disability schemes in Europe is the importance of a comprehensive
strategy to enhance training at the different levels of the care system. Efficient use of the system requires an increase in the health and disability literacy of users and their families, and provision of specific training to informal carers, front-line carers, casemanagers and professionals. The European Commission has established several funding schemes and numerous training programs during the last 15 years (http://ec.europa.eu/education/index_en.htm).
Conclusions The incorporation of severe mental illness into the disability scheme opens a window of opportunity to increase the integration of mental health care, to improve data collection and the standard description of the care system, and to design more effective tools of case identification that incorporate functioning and course of illness. It is also an opportunity to improve the economic analysis and training skills of the different stakeholders implied in mental health care. These factors require more research in Australia to prevent the problems reported in the implementation of disability schemes in other countries. Funding This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
See Viewpoint by Williams and Smith, 2014, 48(5): 391–394
References Arntz M and Thomsen SL (2011) Crowding out informal care? Evidence from a field experiment in Germany. Oxford Bulletin of Economics and Statistics 73: 398–427. Australian Bureau of Statistics (2010) Information Paper: ABS Sources of Disability
Australian & New Zealand Journal of Psychiatry, 48(5)
Downloaded from anp.sagepub.com at NANYANG TECH UNIV LIBRARY on June 2, 2015
484
ANZJP Correspondence
Information Australia 2003–2008. Canberra: Commonwealth of Australia. Australian Institute of Health and Welfare (2012) Disability support services: Services provided under the National Disability Agreement 2010–11. Disability Series. Cat. no. DIS 60. Canberra: AIHW. Büscher A, Wingenfeld K and Schaeffer D (2011) Determining eligibility for long-term carelessons from Germany. International Journal of Integrated Care 11: e019. Duffy S and Williams R (2012) The Road to NDIS: Lessons from England about Assessment and Planning. Unley, South Australia: JFA Purple Orange.
European Commission / Statistical Office (Eurostat) (2003) Feasibility study about comparable statistics in the area of care of dependant adults in the European Union. Luxembourg: Office for Official Publications of the European Communities. Ochoa S, Salvador-Carulla L, Vilalta V, et al. (2012) Use of functioning-disability, and dependency for case-mix and subtyping of schizophrenia. European Journal of Psychiatry 26: 1–12. Salvador-Carulla L, Alvarez-Galvez J, Romero C, et al. (2013) Evaluation of an integrated system for classification, assessment and comparison of services for long-term care in Europe:
The eDESDE-LTC study. BMC Health Services Research 13: 218. Wakefield JC (2009) Disability and diagnosis: Should role impairment be eliminated from DSM/ICD diagnostic criteria? World Psychiatry 8: 87–88. Whiteford HA, Degenhardt L, Rehm J, et al. (2013) Global burden of disease attributable to mental and substance use disorders: Findings from the Global Burden of Disease Study 2010. Lancet 382: 1575–1586. Williams TM and Smith GP (2014) Can the National Disability Insurance Scheme work for mental health? Australian and New Zealand Journal of Psychiatry 48: 390–393.
Drugs and psychosis … and now for some good news Grant E Sara1,2,3
There is growing evidence to support this claim. A meta-analysis of 23 studies by the same authors (Mullin et al., 2012) found that former substance users consistently have fewer positive symptoms and better functioning than people with psychosis who do not use substances. These are clinically significant effects; in more than 600 young people with early psychosis (Lambert et al., 2005), reducing substance use was the strongest predictor of remission. After controlling for age, sex, duration of untreated psychosis and symptom severity, decreasing or ceasing substance use more than doubled the likelihood of remission (hazard ratio 2.44). We have recently examined young people with a first psychosis admission in New South Wales. Of 4933 people who remained in contact with services over 2 years, those with ongoing substance problems had the highest readmission rate (66%), those with no substance disorders had an intermediate rate (50%) and those whose substance problems ceased had the lowest readmission rate (40%) (Sara et al., 2014b). A link between substance use (even if discontinued) and positive outcome in psychosis seems counterintuitive. After all, substance use is associated with other factors usually linked to worse outcome in psychosis, including male gender, earlier onset of psychosis, social disadvantage and a family history of mental health and substance problems. Three
explanations have been proposed to account for this apparent link between substance use and positive outcome: (i) direct chemical effects, (ii) social skills and (iii) personal vulnerability. First, it is possible that substances themselves may have direct positive effects on brain function. Yucel and colleagues (2012) summarise evidence that cannabis use in people with psychosis is associated with better cognitive function as well as with fewer psychotic symptoms, leading to suggestions that cannabis may have direct neuro-protective effects or stimulate prefrontal neurotransmission. It is difficult to reconcile this theory with the harmful effects of ongoing cannabis use; however, our understanding of the effects of cannabis continues to evolve. For example, the interaction of THC and cannabidiols with endocannabinoid receptors is likely to involve both harmful and protective effects (Paparelli et al., 2011). Second, Meuser et al. (1998) have proposed that the association of substances with positive outcome in psychosis is mediated through social competence, whereby more ‘socially oriented patients with serious mental illness are more likely to come into contact with drugs and subsequently develop substance use disorder’ (p.726). In this model, drug use is a marker for better premorbid functioning, greater social skill and therefore better outcome. Evidence to support this
1InforMH,
Mental Health and Drug and Alcohol Office, NSW Ministry of Health, North Sydney, Australia 2Discipline of Psychiatry, Sydney Medical School, University of Sydney, Sydney, Australia 3School of Population Health, University of Queensland, Brisbane, Australia Corresponding author: Grant Sara, InforMH, Macquarie Hospital, PO Box 169, North Ryde, NSW 1670, Australia. Email: [email protected] DOI: 10.1177/0004867414530008
Whether at first contact or in ongoing care, around half of Australians with a diagnosis of psychosis also have a comorbid substance use disorder. In the current issue, Large and colleagues report a systematic metaanalysis which underlines the impact of ongoing substance use on psychotic symptoms (Large et al., 2014). They also touch on an intriguing finding: people with psychosis and substance disorders who cease drug use (‘former substance users’) may have better outcomes than people with psychosis who have never used substances. Put another way, substance use may be a positive prognostic sign in psychosis, as long as substance use is ceased.
Australian & New Zealand Journal of Psychiatry, 48(5) Downloaded from anp.sagepub.com at NANYANG TECH UNIV LIBRARY on June 2, 2015
ANZJP Correspondence
dimensions will complicate trials examining the effects considerably. An alternative solution would be to retain a threshold for the disorders, but combine this with a dimensional approach. So, patients would still receive one or more diagnoses for common mental disorders, but at the same time the most important dimensions can be assessed. This may lead to a more precise diagnosis and more focused interventions, while retaining the advantages of the categorical model. A purely dimensional approach is probably better empirically, but a combined dimensional and categorical approach may be more practical and feasible in the current health care systems. The combined dimensional and categorical approach that was included in the DSM-5 for
personality disorders is a good example of how this could be done in the ICD-11 for the common mental disorders. It is a pity that the dimensional approach in addition or as an alternative to the current categorical approach was not pushed forward in the DSM-5. The ICD-11 offers a new opportunity, and I am sure we all hope that this is not also squandered.
Mental illness and the National Disability Insurance Scheme: Lessons from Europe Luis Salvador-Carulla1,2 and Stewart Einfeld1,2
elderly individuals. Others, such as the Dutch system, were developed in the early 1990s and incorporated mental illness from its onset. In Germany, the main focus was on physical disabilities and did not include mental illness and dementia until 2008. The accumulated wealth of information on the implementation of disability schemes in Europe has been partly overlooked in the development of the NDIS. In addition to the general recommendations made by Williams and Smith, there are practical issues that deserve further analysis such as the contextualisation of the care system, the case identification, the economics of disability, and training in disability care and management.
1Centre
for Disability Research and Policy, University of Sydney, Sydney, Australia 2Brain and Mind Research Institute, University of Sydney, Sydney, Australia Corresponding author: Luis Salvador-Carulla, T424 Cumberland Campus, The University of Sydney, 75 East Street, Lidcombe, NSW 2141, Australia. Email: [email protected] DOI: 10.1177/0004867414531833
Williams and Smith (2014) and Duffy and Williams (2012) discuss a number of pertinent issues regarding implementation of the National Disability Insurance Scheme (NDIS), particularly in light of European experience. The majority of disability systems in Western Europe followed the Recommendation of the European Council in 1998, which was mainly intended to provide support for
Funding This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.
Declaration of interest The author reports no conflicts of interest. The author alone is responsible for the content and writing of the paper.
Context of care Local care systems vary and this leads to very different effects of budgets on outcomes in different countries (Arntz and Thomsen, 2011). Unfortunately, there is a limited number of comparisons of the mental health system in Australia with other countries, and comparisons of the social care system are virtually
References Cuijpers P, De Graaf R and Van Dorsselaer S (2004) Minor depression: risk profiles, functional disability, health care use and risk of developing major depression. Journal of Affective Disorders 79: 71–79. Cuijpers P, Vogelzangs N, Twisk J, et al. (2013) Differential mortality rates in major and subthreshold depression? A meta-analysis of studies that measured both. British Journal of Psychiatry 202: 22–27. Okasha A (2009) Would the use of dimensions instead of categories remove problems related to subthreshold disorders? European Archives of Psychiatry and Clinical Neuroscience 259 (Suppl 2): S129–S133. Widiger TA and Samuel DB (2005) Diagnostic categories or dimensions? A question for the Diagnostic and statistical manual of mental disorders-fifth edition. Journal of Abnormal Psychology 114: 494–504. Watson D (2005) Rethinking the mood and anxiety disorders: A quantitative hierarchical model for DSM-V. Journal of Abnormal Psychology 114: 522–536.
non-existent. As an example, to understand the outcomes of individual budgets in England and Australia it is important to consider that our national system is probably more fragmented and has lower levels of integrated care across sectors. The lack of strong coordination between the social and the health sectors, and the disability and the elderly care sectors have been identified as major problems in the implementation of disability programs in Europe. On the other hand, social and health care systems show large differences within Australia. For example, community care and accommodation support in Victoria was nearly double that of New South Wales (NSW) in 2011 (Australian Institute of Health and Welfare (AIHW), 2012). In the AIHW report, the primary disability groups included 1401 cases with psychiatric disorders in NSW and 14,305 cases in Victoria. These differences point to future disparities in the implementation of the NDIS. Previous experiences in Europe indicate that listing local services by their names may not provide the information required for policy
Australian & New Zealand Journal of Psychiatry, 48(5) Downloaded from anp.sagepub.com at NANYANG TECH UNIV LIBRARY on June 2, 2015
483
ANZJP Correspondence analysis. The 2003 Eurostat report concluded that the statistics concerning formal support were not comparable across European countries due to problems of terminology and definitions (Eurostat, 2003). In 2011, a classification system for coding and mapping long-term care services was released to allow for comparison across European countries (SalvadorCarulla et al., 2013). Similarly, there is a need for standard mapping of mental health interventions and packages of care to improve benchmarking, case management and navigation in the care system.
Identification of cases of disability in severe mental illness The assessment of disability in mental illness is more complex than in any other disability group due to the difficulty of differentiating symptoms from functional impairment (Wakefield, 2009), and in establishing subtypes of disabilities based on severity levels. In 2010, Germany had to revise its eligibility criteria for mental illness (Büscher et al., 2011). In Spain, a report recommended a complementary evaluation and incorporation of tools for casemix and risk pooling and stratification. The report recommended including the level of global functioning, social characteristics (persons with severe mental illness (SMI) living alone, and working/studying), course of illness and services needed on a long-term basis (Ochoa et al., 2012). The Spanish disability scheme opted for a common evaluation system for all disabilities in 2007, and the consequent problems in the eligibility system for SMI required its revision in 2014. The under-reporting of the rates of the ‘profound’ and ‘severe’ categories in the Australian Survey of Mental Health and Wellbeing (Australian Bureau of Statistics, 2010) indicate that similar problems may appear in the identification of SMI in the NDIS in comparison with other disability groups.
Economics of disability A miscalculation in the costs of the various disability schemes has been reported in several European countries after their implementation. Spending on disability support services in Australia increased by 2% to $6.2 billion between 2009/10 and 2010/11 (AIHW, 2012), and a further increase is expected after the implementation of NDIS. A detailed analysis of the cost and financing of disability schemes in other countries may help to design alternative scenarios which are relevant, particularly for complex conditions such as SMI. The field of ‘disability economics’ is in its infancy and there has been an insufficient knowledge transfer from health economics and financing. This has relevant implications for planning disability care. Basic information on the units of cost in the social care sector is missing and it is necessary to design and cost combined packages of care of social and health interventions for SMI with severe disability under the scheme. In addition, tools used in health economics may require significant changes to be applied in disability economics. As an example, disability-adjusted life years (DALYs) is a measure derived from the Global Burden of Disease Study (GBS), which is routinely used in health policy (Whiteford et al., 2013). However, the concept of ‘disability’ in GBS (‘any short-term or long-term health loss’) is too broad to estimate the burden and related costs of groups with severe impairment in the disability scheme. The analysis of financing of disability also deserves more attention. It is essential to identify the financial flows, their incentives and barriers, and the tentative cost-shifting across different sectors, including health, social, housing, employment, education and criminal justice.
Training Another lesson from the development of disability schemes in Europe is the importance of a comprehensive
strategy to enhance training at the different levels of the care system. Efficient use of the system requires an increase in the health and disability literacy of users and their families, and provision of specific training to informal carers, front-line carers, casemanagers and professionals. The European Commission has established several funding schemes and numerous training programs during the last 15 years (http://ec.europa.eu/education/index_en.htm).
Conclusions The incorporation of severe mental illness into the disability scheme opens a window of opportunity to increase the integration of mental health care, to improve data collection and the standard description of the care system, and to design more effective tools of case identification that incorporate functioning and course of illness. It is also an opportunity to improve the economic analysis and training skills of the different stakeholders implied in mental health care. These factors require more research in Australia to prevent the problems reported in the implementation of disability schemes in other countries. Funding This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
See Viewpoint by Williams and Smith, 2014, 48(5): 391–394
References Arntz M and Thomsen SL (2011) Crowding out informal care? Evidence from a field experiment in Germany. Oxford Bulletin of Economics and Statistics 73: 398–427. Australian Bureau of Statistics (2010) Information Paper: ABS Sources of Disability
Australian & New Zealand Journal of Psychiatry, 48(5)
Downloaded from anp.sagepub.com at NANYANG TECH UNIV LIBRARY on June 2, 2015
484
ANZJP Correspondence
Information Australia 2003–2008. Canberra: Commonwealth of Australia. Australian Institute of Health and Welfare (2012) Disability support services: Services provided under the National Disability Agreement 2010–11. Disability Series. Cat. no. DIS 60. Canberra: AIHW. Büscher A, Wingenfeld K and Schaeffer D (2011) Determining eligibility for long-term carelessons from Germany. International Journal of Integrated Care 11: e019. Duffy S and Williams R (2012) The Road to NDIS: Lessons from England about Assessment and Planning. Unley, South Australia: JFA Purple Orange.
European Commission / Statistical Office (Eurostat) (2003) Feasibility study about comparable statistics in the area of care of dependant adults in the European Union. Luxembourg: Office for Official Publications of the European Communities. Ochoa S, Salvador-Carulla L, Vilalta V, et al. (2012) Use of functioning-disability, and dependency for case-mix and subtyping of schizophrenia. European Journal of Psychiatry 26: 1–12. Salvador-Carulla L, Alvarez-Galvez J, Romero C, et al. (2013) Evaluation of an integrated system for classification, assessment and comparison of services for long-term care in Europe:
The eDESDE-LTC study. BMC Health Services Research 13: 218. Wakefield JC (2009) Disability and diagnosis: Should role impairment be eliminated from DSM/ICD diagnostic criteria? World Psychiatry 8: 87–88. Whiteford HA, Degenhardt L, Rehm J, et al. (2013) Global burden of disease attributable to mental and substance use disorders: Findings from the Global Burden of Disease Study 2010. Lancet 382: 1575–1586. Williams TM and Smith GP (2014) Can the National Disability Insurance Scheme work for mental health? Australian and New Zealand Journal of Psychiatry 48: 390–393.
Drugs and psychosis … and now for some good news Grant E Sara1,2,3
There is growing evidence to support this claim. A meta-analysis of 23 studies by the same authors (Mullin et al., 2012) found that former substance users consistently have fewer positive symptoms and better functioning than people with psychosis who do not use substances. These are clinically significant effects; in more than 600 young people with early psychosis (Lambert et al., 2005), reducing substance use was the strongest predictor of remission. After controlling for age, sex, duration of untreated psychosis and symptom severity, decreasing or ceasing substance use more than doubled the likelihood of remission (hazard ratio 2.44). We have recently examined young people with a first psychosis admission in New South Wales. Of 4933 people who remained in contact with services over 2 years, those with ongoing substance problems had the highest readmission rate (66%), those with no substance disorders had an intermediate rate (50%) and those whose substance problems ceased had the lowest readmission rate (40%) (Sara et al., 2014b). A link between substance use (even if discontinued) and positive outcome in psychosis seems counterintuitive. After all, substance use is associated with other factors usually linked to worse outcome in psychosis, including male gender, earlier onset of psychosis, social disadvantage and a family history of mental health and substance problems. Three
explanations have been proposed to account for this apparent link between substance use and positive outcome: (i) direct chemical effects, (ii) social skills and (iii) personal vulnerability. First, it is possible that substances themselves may have direct positive effects on brain function. Yucel and colleagues (2012) summarise evidence that cannabis use in people with psychosis is associated with better cognitive function as well as with fewer psychotic symptoms, leading to suggestions that cannabis may have direct neuro-protective effects or stimulate prefrontal neurotransmission. It is difficult to reconcile this theory with the harmful effects of ongoing cannabis use; however, our understanding of the effects of cannabis continues to evolve. For example, the interaction of THC and cannabidiols with endocannabinoid receptors is likely to involve both harmful and protective effects (Paparelli et al., 2011). Second, Meuser et al. (1998) have proposed that the association of substances with positive outcome in psychosis is mediated through social competence, whereby more ‘socially oriented patients with serious mental illness are more likely to come into contact with drugs and subsequently develop substance use disorder’ (p.726). In this model, drug use is a marker for better premorbid functioning, greater social skill and therefore better outcome. Evidence to support this
1InforMH,
Mental Health and Drug and Alcohol Office, NSW Ministry of Health, North Sydney, Australia 2Discipline of Psychiatry, Sydney Medical School, University of Sydney, Sydney, Australia 3School of Population Health, University of Queensland, Brisbane, Australia Corresponding author: Grant Sara, InforMH, Macquarie Hospital, PO Box 169, North Ryde, NSW 1670, Australia. Email: [email protected] DOI: 10.1177/0004867414530008
Whether at first contact or in ongoing care, around half of Australians with a diagnosis of psychosis also have a comorbid substance use disorder. In the current issue, Large and colleagues report a systematic metaanalysis which underlines the impact of ongoing substance use on psychotic symptoms (Large et al., 2014). They also touch on an intriguing finding: people with psychosis and substance disorders who cease drug use (‘former substance users’) may have better outcomes than people with psychosis who have never used substances. Put another way, substance use may be a positive prognostic sign in psychosis, as long as substance use is ceased.
Australian & New Zealand Journal of Psychiatry, 48(5) Downloaded from anp.sagepub.com at NANYANG TECH UNIV LIBRARY on June 2, 2015
