Depression During the Transition From Adolescence to Adulthood: Potential Protective Factors Depression is a leading cause of disability around the world, affecting approximately 16% of people throughout their lifetime. It is suggested that there may be identifiable factors that differentiate individuals who develop, or have a recurrence of, depression in adulthood. Identification of factors that are associated with depression in early adulthood is important for understanding, preventing, and treating this costly disorder Several studies have looked at factors that put adolescents at risk for depression in adulthood; however, few have looked at factors that may be protective. The primary objective of this study was to identify adolescent protective factors against the onset or recurrence of depressive symptoms in early adulthood, and to understand how protective factors interact with risk factors for depression. This project provides evidence-based information that will be important to policy makers, and further our current understanding of the relationship between adolescent depression and depression in adulthood. The first paper from this project “Social, demographic and health outcomes in the ten years following adolescent depression: evidence from a national Canadian cohort” has been published by the Journal of Adolescent Health. The second paper from this project, “Protective factors against depression during the transition from adolescence to adulthood: findings from a national Canadian cohort” is under review. This project was funded by the M.S.I. Foundation.
Childhood Trauma and Stress Response in Adult Life Traumatic events in childhood are common and may be increasing in frequency. The effects of childhood trauma are significant and have long-lasting effects on health and social functioning. Childhood trauma shows a strong association with depression and alcohol abuse in adulthood. Supporting the link between childhood trauma and adult mental health is a wealth of biological evidence showing an increased stress response among individuals who experience childhood trauma. However, there is little evidence of this in ‘real-world’ population studies. The primary objective of this project was to investigate whether individuals who suffer from traumatic childhood events are more likely to become depressed or abuse alcohol after stressful events in adulthood compared to those without childhood trauma. This study used data from Statistics Canada’s National Population Health Survey to examine these relationships. In this study, we found that childhood trauma increased the risk of depression in adulthood, and multiple traumas dramatically increased the risk. Multiple traumatic events in childhood also increased the risk of alcohol abuse. We found some evidence to suggest that the association between adult stress and depression was stronger among those with childhood trauma. This paper, entitled “Stress and development of depression and heavy drinking in adulthood: moderating effects of childhood trauma“, was published in the journal Social Psychiatry and Psychiatric Epidemiology. This project was funded by the Norlien Foundation and the Women and Children’s Health Research Institute.
Long-Term Outcomes of Depression in the General Population The use of antidepressant medications for the treatment of depression has been rising steadily in recent years. Guidelines for the treatment of depression often recommend antidepressant treatment in patients with severe symptoms and outline specific risk factors supporting long-term treatment maintenance. There is limited knowledge about long-term outcomes associated with antidepressant use in general population samples or other factors that predict long-term prognosis in depression. The primary objective of this project was to use data from a Canadian longitudinal cohort study to determine if individuals with major depression who are treated with antidepressants are less likely to suffer from depression in the long-term future. A secondary objective was to identify sociodemographic and mental and physical health factors associated with a negative long-term prognosis of depression. The studies relating to these two objectives have subsequently been published in two separate manuscripts: “The Association Between Antidepressant Use And Depression Eight Years Later: A National Cohort Study”, published in the Journal of Psychiatric Research, and “Predictors Of Long-Term Prognosis Of Depression”, published in the Canadian Medical Association Journal. This project was funded by the Canadian Institutes of Health Research.
Early-Life Neurodevelopment, Stressful Life Events and Depression Across the Life Course Life course epidemiology seeks to understand how determinants of health and disease interact across the span of a human life. The life course approach is ideal for understanding depression because causation appears to be multifactorial, timing of onset and remission of depression varies widely and early life events and development appear to be important risk factors for depression. This project focused on using the life course approach to understand etiological frameworks of depression. This project investigated evidence of fetal programming in humans by studying whether adolescents born at high or low birth weights are more likely to experience symptoms of depression and anxiety after experiencing stress. The studies relating to this project include: “Life course perspectives on the epidemiology of depression” and “Birth weight, stress, and symptoms of depression in adolescence: evidence of fetal programming in a national Canadian cohort”, both published in the Canadian Journal of Psychiatry.
