Association of Psychiatric and Physical Illnesses with Suicide in Older Adults in Taiwan

Abstract Objective: This study aimed to investigate the association of psychiatric and physical illnesses with suicide in older adults in Taiwan. Methods: A nationwide database in Taiwan was used for this matched case-control study. Elderly participants with and without intentional self-harm from 2010 to 2012 were matched by propensity score by calendar year, gender, age, and area of residence. Psychiatric and physical illnesses were identified by tracing back 1 year from the date of death in suicide and from July 1 of the previous year to June 30 of the observational year in the controls. Associations between illnesses and the risk of suicide was assessed by conditional logistic regression analysis. Results: 2,528 older adults who died by suicide were studied, and the crude suicide mortality rate was 33.7 per 100,000. The risk of suicide in older adults with depression (AOR = 9.06, 95% CI = 6.07–13.52), cancer (AOR = 8.51, 95% CI = 5.39–13.45) and schizophrenia (AOR = 7.34, 95% CI = 2.65–20.33), were significantly higher than control group. Other illnesses, such as bipolar disorder, chronic obstructive pulmonary disease, stroke, chronic kidney disease, hypertension, and diabetes mellitus (AOR = 3.63, 2.41, 1.94, 1.73, 1.68, 1.45, respectively), showed lower risk but still significantly higher in older adults with suicide. Conclusions: Psychiatric and physical illnesses, especially depression, cancer, and schizophrenia, were found to be independently associated with suicide in older adults. The result of this study can help clinicians to identify older adults at risk of suicide and open avenues for prevention.