Suicidal drug overdose in patients with systemic lupus erythematosus, a nationwide population-based case-control study.

ABSTRACT

OBJECTIVE: A four-fold increase of suicide mortality has been demonstrated in systemic lupus erythematosus (SLE) patients. Prior studies showed that the most common method of suicide attempts in SLE patients involves drug overdose. Therefore, we conducted a nationwide population-based case-control study to elucidate factors associated with drug overdose as suicide attempt in SLE patients. METHODS: This study was based on the National Health Insurance Research Database in Taiwan. We identified all SLE patients from January 1, 2000 to December 31, 2010. Patients who had suicidal drug overdose (SDO) were selected as cases while age- and gender-matched patients who did not have SDO were selected as controls. RESULTS: The incidence rate of SDO in SLE patients was 291 cases per 100,000 person-years, higher than that in the general population (160 cases per 100,000 person-years). In a multivariate logistic regression analysis, we observed that SDO was associated with psychiatric disorders such as depressive disorders (odds ratio 8.36, 95% confidence interval (CI) 5.60-12.48) and insomnia (odds ratio 2.71, 95% CI 1.73-4.25), and lower monthly income (odds ratios 2.74 to 3.50) in SLE patients. CONCLUSION: SDO is associated with psychiatric disorders such as depressive disorders and insomnia, and lower monthly income in SLE patients.