Anti-anxiety drugs use and cardiovascular outcomes in patients with myocardial infarction: A national wide assessment

Objective: Anti-anxiety medication in patients with anxiety may lessen the stress and thereby lower their risk for myocardial infarction (MI). The aim of current study is to examine an association between the use of anti-anxiety medication and long-term mortality risk in patients following MI. Methods: A universal national health insurance (NHI) program has been implemented in Taiwan since 1995. We used system sampling database from 1997 to 2008 with a total of 1,000,000 subjects. We included subjects with first episode of MI and were above 30 years old. Sudden death, cardiovascular mortality, and heart failure hospitalization were assessed in all included subjects. Anti-anxiety as well as other medications and risk factors were obtained. Cox regression analysis was used to evaluate the adjusted hazard ratio (HR) for all patients and subgroups. Results: The adjusted HRs of sudden death were significantly associated with increased benzodiazepam (BZD) dosage (HRs=0.639, 1.003, 1.957 from Q2 to Q4 vs. Q1, p=.019 for trend) during approximately 4.8 years. For cardiac mortality and heart failure hospitalization, there was a J-curve dose-response relationship. The HRs for cardiac mortality were 0.255 (p<.001) and 0.385 (p<.001) for Q2 and Q3 vs. Q1, respectively. For patients receiving higher doses of daily BZDs (>5mg), protective effects for cardiac mortality and heart failure hospitalization decreased and a J-curve dose-response relationship was seen. Conclusion: Anti-anxiety medications are independent associated with a decreased risk of cardiac mortality and heart failure hospitalization in patients after a new MI.