Alcohol and illicit drug dependence.

OBJECTIVES This article estimates the prevalence of alcohol and illicit drug dependence among Canadians aged 15 or older Comorbidity with depression is examined. DATA SOURCES The data are from the 2002 Canadian Community Health Survey: Mental Health and Well-being and the National Population Health Survey. ANALYTICAL TECHNIQUES Cross-tabulations were used to estimate the prevalence of alcohol and illicit drug dependence by selected characteristics. Multiple logistic regression models were used to determine if associations persisted after controlling for potentially confounding factors, and to test temporal relationships between frequent heavy drinking and depression. MAIN RESULTS In 2002, an estimated 641,000 people (2.6% of the household population aged 15 or older) were dependent on alcohol, and 194,000 (0.8%), on illicit drugs. These people had elevated levels of depression compared with the general population. Heavy drinking more than once a week was a risk factor for a new episode of depression, and depression was a risk factor for new cases of frequent heavy drinking.