Congenital heart disease and risk of suicide and self-harm: A danish nationwide cohort study

Abstract

BACKGROUND: In this nationwide study, we used the unique Danish registries to estimate the risk of suicide and deliberate selfharm in patients with congenital heart disease (CHD). METHODS AND RESULTS: We identified all Danish citizens receiving a diagnosis of CHD between 1977 and 2007. As a reference cohort, we randomly selected 10 citizens for each patient, matched by sex and birth year. Using the Fine and Gray competing risk regression, we estimated the cumulative incidences of suicide and self-harm, and Cox proportional regression analysis was used to compare the risk of suicide and deliberate self-harm in patients with CHD with the reference cohort. We identified 14 433 patients with CHD. Mean follow-up was 21.3 years, with a maximum follow-up of 42 years. Since the time of diagnosis, 2659 patients had died, with a median age of death of 23 years. A total of 15 patients had died by suicide, compared with 232 suicides in the reference cohort. Patients with CHD had a low and similar risk of dying by suicide when compared with the reference cohort (cause-specific hazard ratio, 0.81; 95% CI, 0.48–1.37; and subhazard ratio, 0.68; 95% CI, 0.41–1.16). We identified 336 events of self-harm among patients with CHD, and 3484 events in the reference group. The overall risk of deliberate self-harm was not increased in patients with CHD when compared with the reference group (subhazard ratio, 0.95; 95% CI, 0.85–1.06). CONCLUSIONS: This is the first study to estimate the risk of suicide and deliberate self-harm in patients with CHD. We found that patients with CHD do not have an increased risk of suicide or deliberate self-harm when compared with a large reference cohort.