Co-Occurring Substance Misuse is associated with negative effects on psychiatric illnesses with implications for medication compliance, relapse and treatment outcome.

To contribute to research in the area of Co-occurring Substance Misuse in the Caribbean in general and Jamaica in particular.

To determine the prevalence of Co-occurring Substance Misuse, associated demographic characteristics and reports of interpersonal violence.

A cross-sectional study design was used with consenting patients admitted to the Psychiatric Unit at the University Hospital of the West Indies, Kingston over the period March 2011 to September 2011. Data collection utilized a researcher administered Background Questionnaire. Data analysis was done using the Statistical Package for the Social Sciences Version 18.0 (SPSS 18.0).

Of 100 consenting patients, 36 (36%) were diagnosed as having Co-occurring Substance Misuse, 31 (83.8%) males and 5 (13.5%) females, mean age 27.17 ± 9.6 years, range 14-59 years. Past year alcohol (86.5%), tobacco (86.5%), marijuana (89.2%) and cocaine (13.9%) use were reported, with the majority of patients (94.4%) reporting polysubstance use. The mean age of onset for alcohol was 14.3 yrs, tobacco, 14.8 yrs, cannabis, 16.5 yrs and cocaine 21.4 years. 70% were diagnosed with a Psychotic Disorder and 30% had a Mood Disorder. A high prevalence of interpersonal violence (77.8%) was reported.

There is a high prevalence of Co- morbid Substance Misuse in this sample of patients. Patients should be screened on admission for Co-morbid Substance Misuse and a combined, integrated approach to the management of these patients should be established.