Depression is one of the most widespread mental disorders among adults throughout the world. Now, a large study that has spanned more than 60 years has confirmed that both men and women who have had at least one major depressive episode have a significantly higher risk of mortality than others.
A major depressive episode is considered when 5 or more of the following symptoms are constantly present over a 2-week period : depressed mood, loss of pleasure in normally jovial activities, abnormal weight loss or weight gain, insomnia, or excessive sleepiness , agitation or abnormal physical slowness, fatigue, feelings of guilt or worthlessness, poor concentration and recurring thoughts about death.
Previous studies have already linked depression to an increased risk of cardiovascular disease and sudden cardiac death, especially in women.
In this research, developed by scientists from all institutions in the US and Canada, including the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the School of Epidemiology at the University of Ottawa in Ontario, Canada, major depressive episodes as a significant risk factor for early death for both men and women.
The scientists analyzed data obtained from 3,410 Atlantic Canada adults enrolled in the Stirling County study, with a focus on gaining a better understanding of various mental illnesses. In the current research, the authors were interested in seeing to what extent depression was related to an increased risk of mortality and if this risk was different for men than for women.
They conducted their study for more than 60 years, analyzing data from participants enrolled during three different periods: 1952-1967 (1,003 participants), 1968-1990 (1,203 participants), and 1991-2011 (1,402 participants). The average age of the participants at the time of enrollment was 49 years.
After examining the data, the experts found a strong connection between a diagnosis of depression and a significantly higher risk of mortality for men in all three periods. For women, however, a link between depression and risk of death was only seen from the 1990s onwards.
“Our results show that a depressive episode confers a high risk of mortality that eventually decreases over time unless there is a recurrent depressive episode, in which case the risk of mortality associated with depression remains high,” the authors clarify.
“The life expectancy of young adults with depression at age 25 was markedly shorter during the 60-year period, 10 to 12 years shorter in life in the first group, 4 to 7 years in the second group, and 7 to 18 years less life in the 1992 group “, explains Ian Colman, co-author of the work.
Increased depression in women
What they found particularly concerning, however, was the steep increase in mortality risk for women with depression in the most recent cohort: “Most disturbing is the 50% increase in the risk of death for women with depression between 1992 and 2011, “says Colman.
In the case of women, the increased risk of mortality associated with depression could be explained by the increasing volume of responsibilities.
“During the last 20 years of the study in which the risk of death of women increased significantly, roles have changed dramatically both at home and at work, and many women have multiple responsibilities and expectations,” says Colman.
Reference: Depression and mortality in a longitudinal study: 1952–2011. Stephen E. Gilman, Ewa Sucha, Mila Kingsbury, Nicholas J. Horton, Jane M. Murphy, Ian Colman. October 2017. Canadian Medical Association Journal
