Socioeconomic status and incidence of hospitalization with lower-extremity peripheral artery disease: Atherosclerosis risk in communities study

Background--Compared to coronary heart disease, heart failure, and stroke, the relationship between low socioeconomic status (SES) and peripheral artery disease (PAD) is less well established. We examined the association between SES and incidence of hospitalization with PAD and explored whether this association can be explained by traditional cardiovascular risk factors and healthcare access. Methods and Results--A total of 12 517 participants in the Atherosclerosis Risk in Communities (ARIC) Study (1987-1989) with no prior PAD were examined. Individual-level SES was assessed from household income (low < $12 000/year, medium $12 000 to $24 999/year, and high ≥$25 000/year [double to approximate to values in 2016]) and educational attainment (< high school, high school, and > high school), and area-level SES from area deprivation index (quintiles). During a median follow-up of 23.6 (Interquartile range 19.6-24.5) years, 433 participants had a hospitalization with PAD. In Cox proportional hazards regression analysis, the demographically adjusted hazard ratio was 2.42 (1.81-3.23) for low household income, 2.08 (1.60-2.69) for low educational attainment, and 2.18 (1.35-3.53) for most deprived neighborhoods, compared to their high-SES counterparts. After adjustment for traditional cardiovascular risk factors and heath care access, the associations were attenuated but remained significant, particularly for income and education. Results were consistent when stratified by race (P-values for interaction > 0.2 for all SES parameters). Conclusions--Low individual- and area-level SES are strong predictors of hospitalization with PAD, in part due to increased prevalence of cardiovascular risk factors and poor access to care in these groups. Additional risk factors may also need to be identified and acted on to eliminate SES disparities in PAD hospitalization.