Risk and protective factors for suicide mortality among patients with alcohol dependence

Objective: People with alcohol dependence suffer from poor health outcomes, including excessive suicide mortality. This study estimated the suicide rate and explored the risk and protective factors for suicide in a large-scale Asian population. Method: We enrolled patients with alcohol dependence (ICD-9 code 303) consecutively admitted to a psychiatric center in northern Taiwan from January 1, 1985, through December 31, 2008 (N = 2,793). Using patient linkage to the national mortality database (1985-2008), we determined that 960 patients died during the study period. Of those deaths, 65 patients died of suicide. On the basis of risk-set sampling for the selection of controls, we conducted a nested case-control study and collected the information by means of a standardized chart review process. We estimated the standardized mortality ratio (SMR) for suicide mortality. Conditional logistic regression was employed for exploring the risk and protective factors for suicide. Results: The study subjects had excessive suicide and all-cause deaths, with SMRs of 21.2 and 12.7, respectively. We pinpointed auditory hallucination (adjusted risk ratio [aRR] = 1.80, P = .04) and attempted suicide (aRR = 7.52, P = .001) as the risk factors associated with suicide. In contrast, protective factors included financial independence (aRR = 0.11, P = .005) and being married (aRR = 0.16, P = .02). Intriguingly, those with physical illnesses had a lower risk of suicide (aRR = 0.15, P = .01). Conclusions: Compared with the general population, those with alcohol dependence faced excessive suicide mortality. For a comprehensive approach to suicide prevention, recognizing and improving the protective factors could have equal importance in mitigating the risk of suicide.