The main reason for conducting this study is because the concept of alcohol and cannabis use and its relation to first-episode psychosis is a relatively new concept. Most research into the role of substance misuse has focused on cannabis and very little has been published in recent years on the role of alcohol misuse on psychosis. Therefore, this study will replicate earlier findings of the impact of cannabis on psychosis and the relapse consequences related to it (i.e. more inpatient admissions and more contact with mental health services). Moreover, it will provide up to date information on whether alcohol use also results in high relapse rates and therefore is associated with increased contact with mental health services in particular, home treatment teams. Although a majority of patients who come into contact with mental health services have substance use problems, as yet not many attempts have been made to understand the human and financial cost of this problem in mental health services. Further research is needed to establish the impact that increased alcohol and cannabis abuse will have on the health service.
Substance abuse, which includes alcohol and street drugs, is widespread among first-episode psychosis patients, in particular cannabis abuse (Van Mastrigt S et al, 2004). Cannabis use is mostly been found among younger people with first-episode psychosis whereas alcohol is most commonly abused among older people with chronic schizophrenia (Akvardar Y, et al, 2004). Research in the UK suggests that patients with psychosis who had substance use problems contacted mental health services more often or spent more days in hospitals compared with patients who did not have substance use issues (Mezenes et al, 1996, Bartels et al, 1993). Similarly, participants with co morbid substance abuse and FEP had considerably higher hospital admission rates than FEP participants who did not abuse substances (Wade D, et al, 2006).
However, other studies found diverse results. For instance, in a highly influential paper by Cantwell R, 2003 has revealed that people with substance use problems presenting with psychotic symptoms were no more likely than those without substance use problems to have accessed primary care or to have had contact with other specific individuals in secondary care services within the preceding year. Neither were they more likely to have attended general hospitals or accident and emergency departments. In sharp contrast, a recent UK study with 115 patients in a psychiatric intensive care unit concluded that 71.3% of the sample was using cannabis and this use resulted in more days spent at the hospital compared to those who did not use cannabis as well as these individuals showed more severe psychotic symptoms (Isaac et al, 2005).
Although a majority of patients who come into contact with mental health services have substance use problems (Wright et al, 2002), as yet not many attempts have been made to understand the human and financial cost of this problem in mental health services. According to a very recent report published by NHS confederation in September 2009 stated that "people who have developed problems with alcohol or drugs because of a pre-existing mental health condition, or have had a mental health condition caused by substance misuse, use services more and cost the NHS more. Furthermore, a study of services in London cited in the report showed more patients with dual diagnosis used community psychiatric nurses, inpatient care and emergency clinics. This costs the NHS £1,362 more per patient in "core psychiatric services costs, and £1,360 in non-accommodation service costs when compared with patients without dual diagnosis.
In summary, Comorbidity of mental illness and substance misuse has been associated with increased psychiatric admission (Hunt et al, 2002) as well as excess service costs (Hoff & Rosenheck, 1999) and therefore improving management of Comorbidity is now a priority of National Health Service (NHS) in the UK (Banerjee et al, 2002). Therefore, the main aims of this study are;
- To examine whether alcohol and cannabis users with first onset psychosis have more psychiatric admissions or contact home treatment teams more often because of increased incidence of relapse for psychotic symptoms?
- To investigate the cost of psychiatric admissions and home treatment teams contacts in a 12 month follow-up period.
- To determine whether there are any differences between cannabis users and alcohol users on type of contact and costs.
- Patients with a history of alcohol and cannabis misuse with first-onset psychosis will be more likely to be admitted as inpatients.
- Patients with a history of alcohol and cannabis misuse with first-onset psychosis will contact home treatment teams more often compared to non-users.
- Therefore this would increase the cost towards the mental health services because of increased incidence of relapse for psychotic symptoms.
Design: a prospective, observational cohort study will be used to look at multiple explanatory factors. People with first episode psychosis will be followed-up for 12 months of duration.
Participants: the study will use minimum 150 patients presented with first onset psychosis. South London and Maudsley (SLAM) patients will be asked to take part in this study. Clinical assessments will be performed at baseline and at 1 year.
The inclusion criteria for the study is age 18-65 years, fluency in English, ability to give informed consent, and clear evidence of a functional psychotic disorder. All psychotic illnesses including drug-induced psychosis will be included in the study (schizophrenia, schizoaffective disorder, delusional disorder, depression with psychotic symptoms, and mania with psychotic symptoms).
The exclusion criteria is organic aetiology, learning disability, history of brain damage or epilepsy, pregnancy, major medical illness, major neurological disease, history of previous contact with health (GP or Psychiatric) services for the presence of psychosis.
Measures: Key contacts record form, cannabis experiences questionnaire, alcohol use disorders questionnaire and interviews.
As the study will involve use of data which has already been collected, ethic approval for the study has previously been granted.
Data will be analysed using STATA 9 and SPSS v 15.0. A description of the participants will be presented using means and standard deviations (SD) or proportions (%). Repeated measures analysis and missing data analysis will be conducted using SPSS. Association between alcohol and cannabis use at baseline and the number of contact with home treatment teams at 12 months will be analysed using generalised linear models (Poisson regression) as well as associations between alcohol and cannabis use and relapse rates at 12 months.
Most Relevant References:
- Cantwell R, Brewin J, Glazebrook C, Dalkin T, Fox R, and Medley I, Harrison G (1999) Prevalence of substance misuse in first-episode psychosis. Br J Psychiatry 174: 150-153
- Mezenes PR, Johnson S, Thornicroft G, Marshall J, Prosser D, Bebbington P, Kuipers E (1996) Drug and alcohol problems among individuals with severe mental illnesses in South London. BR J Psychiatry 168: 612-619
- Seeing double: meeting the challenge of dual diagnosis, NHS Confederation 2009