Sex Disparity in Suicide Mortality among Patients with Type 2 Diabetes: A Nationwide Population-Based Cohort Study

Suicide represents a major public health concern in Korea. Patients with type 2 diabetes mellitus (T2DM) are at higher risk for psychological distress and suicide. Although the male-to-female suicide mortality ratio in the general population has remained about 2.3, the specific differences in suicide mortality by sex among individuals with T2DM are not well characterized.

We performed a nationwide cohort study utilizing the Korean National Health Insurance Service database, identifying 2,526,769 adults with T2DM who underwent health screening from 2015 to 2016. Participants were monitored until the occurrence of suicide or the study endpoint.

During a median follow-up of 6.0 years, 5,584 suicide deaths occurred (0.30% in men vs. 0.10% in women). Men exhibited a significantly elevated risk of suicide mortality compared to women (adjusted hazard ratio [HR], 2.88; 95% confidence interval [CI], 2.66 to 3.12). The largest disparity was observed in the ≥80 age group (HR, 3.60; 95% CI, 2.88 to 4.51). However, this sex disparity in suicide mortality was reduced among current smokers and heavy alcohol consumers. Among non-smokers, the HR comparing men to women was 3.51 (95% CI, 3.22 to 3.83), while among current smokers, it was 1.73 (95% CI, 1.40 to 2.14). Similarly, the HR among non-drinkers was 3.04 (95% CI, 2.79 to 3.31), compared with 1.36 (95% CI, 0.85 to 2.18) among heavy drinkers.

Men with T2DM had a significantly higher risk of suicide mortality than women, exceeding the sex disparity seen in the general population, with the gap further influenced by age and lifestyle factors.