Association between social integration and suicide among women in the United States

Résumé

textbfImportance: Suicide is one of the top 10 leading causes of mortality among middle-aged women. Most work in the field emphasizes the psychiatric, psychological, or biological determinants of suicide. textbfObjective: To estimate the association between social integration and suicide. textbfDesign, Setting, and Participants: We used data from the Nurses' Health Study, an ongoing nationwide prospective cohort study of nurses in the United States. Beginning in 1992, a population-based sample of 72607 nurses 46 to 71 years of age were surveyed about their social relationships. The vital status of study participants was ascertained through June 1, 2010. textbfExposures: Social integration was measured with a 7-item index that included marital status, social network size, frequency of contact with social ties, and participation in religious or other social groups. textbfMain Outcomes and Measures: The primary outcome of interest was suicide, defined as deaths classified using the codes E950 to E959 from the International Classification of Diseases, Eighth Revision. textbfResults: During more than 1.2 million person-years of follow-up (1992-2010), there were 43 suicide events. The incidence of suicide decreased with increasing social integration. In a multivariable Cox proportional hazards regression model, the relative hazard of suicide was lowest among participants in the highest category of social integration (adjusted hazard ratio, 0.23 [95% CI, 0.09-0.58]) and second-highest category of social integration (adjusted hazard ratio, 0.26 [95% CI, 0.09-0.74]). Increasing or consistently high levels of social integration were associated with a lower risk of suicide. These findings were robust to sensitivity analyses that accounted for poor mental health and serious physical illness. textbfConclusions and Relevance: Women who were socially well integrated had a more than 3-fold lower risk for suicide over 18 years of follow-up. ÉTATS-UNIS FEMME ÂGE ADULTE AÎNÉ INTÉGRATION-SOCIALE FACTEUR-PROTECTION