Isotretinoin is the most effective medication in the treatment of severe recalcitrant nodular acne. However, case reports have suggested a controversial association between isotretinoin and depression. Although several observational studies investigated this association, none of them have produced significative results. These studies involved either small sample sizes or had no appropriate control groups.

The primary objective of this research project was to determine whether isotretinoin increases the risk of depression in patients with acne vulgaris from 1984 throught 2003 in the province of Quebec. Moreover, we sought to 1) describe the patterns and trends of isotretinoin utilization, 2) describe the characteristics of isotretinoin users within that same time period, 3) identify and quantify predictors of isotretinoin use, 4) identify and quantify predictors of acne relapse, and 5) describe the impact of guidelines on isotretinoin utilization. These different aspects of Isotretinoin use were studied using data from the Isotretinoin users cohort.

Funding source
Canadian Institutes of Health Research (CIHR).