The relationship between peripheral arterial disease severity and allostatic load: A national health and nutrition examination survey study

Major socioeconomic disparities persist in the management and outcomes of peripheral artery disease (PAD) globally. Allostatic load, which is described as a measure of physiologic adaptation to socio-environmental stress, has been reported to partially explain higher mortality rates in US Blacks. However, it is not clear if allostatic load is associated with PAD severity. The National Health and Nutrition Examination Survey (NHANES), 2003-2004 data was used to identify individuals with PAD based on the calculated Ankle-Brachial Index (ABI). After allostatic load was calculated for each individual, the cohort was stratified into tertiles of allostatic load and survey weights were used to generate nationally representative estimates. Factors associated with increased severity of PAD were evaluated using multivariate regression analyses. There were 5589 individuals included in the survey and 239 (5.9%) had PAD (ABI ≤ 0.9). Using survey weights, this corresponded to 5.9 million individuals. Individuals with PAD were more likely in the highest tertile of allostatic load (71%) compared to the middle (28%) or lowest (6%) tertiles. However, when severity of PAD was examined, the odds of moderate-to-severe PAD were not significantly different among individuals in the middle [adjusted Odds Ratio: 2.02 (0.52 - 7.80)] or highest [adjusted Odds Ratio: 2.53 (0.69 - 9.26)] tertiles compared to those in the lowest tertile. This study suggests that PAD severity is not associated with allostatic load. Increased efforts are necessary to identify factors that explain the socioeconomic disparities observed in the management and treatment of PAD.