Sex-specific incidences and risk profiles of suicide mortality in people with alcohol dependence in Taiwan

Background and aims: Alcohol-related mental health burden and suicidality impose heavy burdens on global public health. This study measured the sex-specific incidence and risk profiles of suicide mortality in individuals with alcohol dependence in a non-western context. Design: In this prospective cohort study, individuals with alcohol dependence who were enrollees in Taiwan’s National Health Insurance Research database were followed-up over an almost 15-year period. Their data were linked to the national mortality registration database. Setting: Taiwan. Participants: In total, 278 345 patients with alcohol dependence were enrolled and followed-up from 1 January 2001 to 31 December 2016. Measurements: We calculated the incidence and standardized mortality ratio (SMR) of suicide in the cohort and stratified the suicide methods by sex. Sex-specific risk profiles (based on demographic characteristics and physical and psychiatric comorbidities) were generated through Cox proportional hazards regression. Findings: The suicide rates of men and women were 173.5 and 158.9 per 100 000 person-years, respectively (P = 0.097). The SMR of suicide mortality was more than two times higher in women than in men (6.6 versus 15.0). Women and men adopted different suicide methods. A multivariable Cox proportional hazards regression with a time-varying model revealed that depressive disorder was a common risk factor for suicide in both men and women [adjusted hazard ratio (aHR) = 3.03, 95% confidence interval (CI) = 2.77-3.31 versus aHR = 5.46, 95% CI = 4.65-6.40]. For men, receiving a diagnosis of alcohol dependence between the ages of 25 and 44 years, being unemployed and having schizophrenia, drug-induced mental disorder or sleep disorder were risk factors for suicide. Conclusion: In Taiwan, the incidence of suicide in patients with alcohol dependence is substantially higher than that of the general population. The standardized mortality ratio of suicide in women with alcohol dependence is more than twice that of men with alcohol dependence.