Schizophrenia and comorbid self reported cannabis abuse: impact on course, functioning and services use

To examine the impact of cannabis abuse on the short term outcome in terms of relapses, use of services, compliance and functioning in patients with schizophrenia.

A case control study was conducted in the Department of Psychiatry PGMI Lady Reading Hospital, Peshawar from January 2004 to October 2004. Fifty schizophrenic patients with co-morbid misuse of cannabis were selected. Fifty schizophrenic patients who were not using cannabis were selected as control group for the study. Data regarding socio-demographic detail, relapse, compliance to drugs and service utilization was collected with the help of a Performa. Problem cannabis use in the past year and social assessment of functioning were assessed with the help of Schedule for Clinical assessment in Neuropsychiatry (SCAN) and Global Assessment of Functioning (GAF) scale respectively.

Schizophrenic patients with cannabis use were younger on admission and had younger age at onset of illness. They had more number of relapses and more contacts with psychiatric services including the police. Patients with comorbid cannabis use had poor drug compliance and their relapses were preceded by poor drug compliance Cases and control did not differ significantly on score of Global assessment of functioning.

Comorbidity of cannabis seems to have adverse effects on almost all domains of the illness including course, service use and drug compliance.