Mental illness and substance use are overrepresented within urban homeless populations. This paper compared substance use patterns between homeless individuals diagnosed with schizophrenia spectrum (SS) and bipolar disorders (BD) using the Mini-International Neuropsychiatric Interview. From a sample of 497 subjects drawn from Vancouver, Canada who participated in the At Home/Chez Soi study, 146 and 94 homeless individuals were identified as BD and SS, respectively. In the previous 12 months, a greater proportion of BD homeless reported greater use of cocaine (χ 2 = 20.0, p = 0.000), amphetamines (χ 2 = 13,8, p = 0.000), opiates (χ 2 = 24.6, p = 0.000), hallucinogens (χ 2 = 11.7, p = 0.000), cannabinoids (χ 2 = 5.05, p = 0.034), and tranquilizers (χ 2 = 7.95, p = 0.004) compared to SS. Cocaine and opiates were significantly associated with BD homeless (χ 2 = 39.06, df = 2, p < 0.000). The present study illustrates the relationship between substance use and BD in a vulnerable urban population of homeless, affected by adverse psychosocial factors and severe psychiatric conditions.
*“Vincent P. Dole” Dual Diagnosis Unit, Department of Clinical and Experimental Medicine, University of Pisa; †Association for the Application of Neuroscientific Knowledge to Social Aims (AU-CNS), Pietrasanta, Lucca, Italy; ‡Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada; §Medical University of Vienna, Neuroimaging Labs, Austria; ∥Institute of Mental Health, Department of Psychiatry, and ¶Department of Psychiatry, University of British Columbia; #Centre for Health Evaluation and Outcome Sciences, St. Paul’s Hospital; and **School of Population and Public Health, University of British Columbia, Vancouver, BC, Canada.
Send reprint requests to Angelo G.I. Maremmani, MD, Vincent P. Dole Dual Diagnosis Unit, Department of Clinical and Experimental Medicine, Santa Chiara University Hospital, University of Pisa, Via Roma, 67 56100 Pisa, Italy. E-mail: email@example.com.