Browsing by Author "Stenroos, Anna"

Objective: Substance use has been seen as a way to cope with stress and to influence internal states. Because stressful life events have been considered as a risk-factor for depression, the connection between stressful life events and depression offer an interesting framework to investigate the effects of self-medication. This study examined how stressful life events, alcohol usage and smoking effect depression, and if substance use moderates the relationship between stressful life events and depression. Methods: This research is part of an older Finnish Twin Cohort study and data from the 2011 follow-up questionnaire study was used. Additionally data from questionnaire studies conducted in 1981 and 1975 was used to control for educational achievement. Depression was assessed with the Center for Epidemiologic Studies Depression Scale (CES-D) questionnaire. Alcohol consumption was assessed by used grams per month and smoking was measured by smoking status, based on a detailed smoking history. Stressful life events were measured by 12 questions designed to gather information on a wide range of experiences. Multi-level logistic regression analyses were used to account for clustered twin pairs. In addition twins were compared with pairwise t-tests. Results and conclusions: Stressful life events, smoking and greater alcohol usage predicted depression. Genetic and familial-environmental background did not entirely explain the observed associations, but evidence suggests causality. Especially dependent life events, in which the person has had a substantial contribution, seemed to be related to depression. The amount of used alcohol or smoking did not reduce the relationship between stressful life events and depression. If tobacco and alcohol are used as self-medication, they do not seem to have the wanted effects, at least not in the long run.