Suicide and marital status in Northern Ireland

Introduction: Studies show marriage to be protective against suicide though with variation in the extent to which suicide rates are higher among the never married, separated or divorced and widowed. We examined suicide in Northern Ireland by marital status and examined whether the observed variation differed by sex and age. Methods: Data relating to all 1,398 suicide deaths (ICD-9 E950-959 and ICD-10 X60-84) registered in 1996-2005 were analysed using Poisson regression. Results: The total, male and female age-standardised suicide rates were 8.4, 13.6 and 3.3 per 100,000, respectively. Never marrying increased male suicide risk and its effect increased with age (incidence rate ratio (IRR) among 20-34 year-olds = 1.47, 95% confidence interval (CI) = 1.19-1.84; IRR among over 55 year-olds = 2.33, 95% CI = 1.55-3.50). Never marrying was a risk factor for women only if aged 20-34 years (IRR = 3.05, 95% CI = 1.70-5.47). Among over 55 year-olds, widowhood increased risk of male suicide only (IRR = 2.47, 95% CI = 1.64-3.70) whereas divorce was associated with an almost threefold increase in male (IRR = 2.61, 95% CI = 1.39-4.88) and female (IRR = 2.57, 95% CI = 0.89-7.42) suicide relative to married persons. The effect of divorce was far more pronounced in 20-34 year-old men (IRR = 5.59, 95% CI = 3.58-8.67) and women (IRR = 9.46, 95% CI = 3.81-23.37). Conclusions: In Northern Ireland, marriage protects both sexes against suicide though men more so than women. Divorced young men, in particular, are a population at high risk of suicide.