Bidirectional associations between anxiety disorders and myocardial infarction: a retrospective longitudinal cohort study

BACKGROUND: Despite anxiety and coronary heart disease being associated, longitudinal research investigating the bidirectional relationship between the formal diagnosis of anxiety disorders and myocardial infarction (MI) remains scarce. OBJECTIVE: To investigate the bidirectional relationship between anxiety disorders and MI through a 15-year (2002-2016) longitudinal population-based retrospective cohort study using the National Health Insurance Research Database. METHODS: We selected 34,979 patients diagnosed with an anxiety disorder based on their claim records during 2002-2004 and 5,189 patients with a diagnosis of MI based on their claim records during 2002-2004. In both analyses, the size of the comparison group was four times larger than that of the exposed group. A Cox proportional hazards model was used to estimate adjusted hazard ratios for developing anxiety disorders or MI after adjusting for sociodemographic factors. RESULTS: In the first analysis, patients with anxiety disorders had a statistically significant 1.28-fold higher risk of MI than those without. Among the patients with anxiety, those with higher age, male sex, or lower comorbidity had a significantly higher risk of MI after adjusting for sociodemographic variables. In the second analysis, patients with MI had a statistically significantly 2.08-fold higher risk of anxiety disorders than those without MI. Among the patients with MI, women and patients with lower comorbidities had a significantly higher risk of anxiety disorders after adjusting for sociodemographic variables. CONCLUSION: Our results demonstrate a meaningful connection between anxiety disorders and MI. By recognizing this relationship, healthcare providers can develop constructive strategies to effectively manage both conditions and improve patient outcomes.