Socioeconomic status and depression as combined risk factors for acute myocardial infarction and stroke: A population-based study of 2.7 million Korean adults

To evaluate the separate and combined associations of socioeconomic status (SES) and depression with the incidences of acute myocardial infarction (AMI) and stroke. We conducted a population-based cohort study using nationwide health insurance claims data collected from 2002 to 2016 in South Korea. A total of 2,705,090 subjects aged 20 years or older for whom had health screening data were collected between 2004 and 2005 were analyzed. The hazard ratios (HRs) for the incidences of AMI and stroke were calculated using Cox proportional regression analyses. After adjusting for cardiovascular risk factors, a low SES was associated with increased risks of AMI (HR, 1.16; 95% confidence interval (CI), 1.14–1.19) and stroke (HR, 1.13; 95% CI, 1.11–1.14) incidence. Depression was also associated with an increased incidence of AMI (HR, 1.26; 95% CI, 1.21–1.31) and stroke (HR, 1.24; 95% CI, 1.21–1.27). Patients with depression who had a low SES exhibited significantly increased risks of AMI (HR, 1.47; 95% CI, 1.36–1.60) and stroke (HR, 1.37; 95% CI, 1.30–1.44) compared to patients with a high SES who were not diagnosed with depression. Depression showed a positive effect modification of low and medium SES compared to high SES on the association with AMI but not with stroke. Subjects with both a low SES and depression displayed the highest risk. Both SES and depression should be considered in cardiovascular risk assessments, particularly in individuals with depression who have a low SES. •A low SES and depression are separately associated with increased risks of AMI and stroke, respectively.•The excess risk observed for patients with a low SES and depression was 47% for AMI and 37% for stroke compared with the risks observed for patients with a high SES without depression.