The Influence of the Socioeconomic Status and the Density of the Population on the Outcome After Peripheral Artery Disease

Background: Low socioeconomic status (SES) and living in a rural environment are associated with poorer health and a higher number of amputations among the population at large. The purpose of this study is to determine the influence of low SES and of the degree of urbanization on the short-term and long-term results of patients after revascularization for peripheral artery disease. Methods: An observational retrospective follow- up study of 770 patients operated on for peripheral artery disease at three university centers in north-western Spain from January 2015 to December 2016. The events studied were Rutherford classification of severity upon admission, direct amputation, amputations in the follow-up period, new revascularization procedures, major adverse cardiovascular events (MACE), and overall mortality. Mean personal income and income of the household associated with the street in which each patient lived and the degree of urbanization in three areas as per Eurostat criteria: densely populated areas, intermediate density areas, and thinly populated areas. Comorbidity, surgical, and follow- up variables were also collected. Descriptive analysis and Cox regression were used. Approval was obtained from the regional ethics committee. Results: Median follow-up was 47.5 months. MACE occurred in 21.5% of the series and overall mortality was 47.0%. Living in a thinly populated area is associated with a lower risk of MACE (adjusted subhazard ratio = 0.60; 95% confidence interval [CI]: 0.39-0.91). Overall survival is lower in intermediate density area patients (adjusted Hazard Ratio = 1.46; 95% CI: 1.07-2.00). The third quartile of mean personal and household income is associated with a higher risk of major amputation at follow-up (adjusted Odds Ratio 1.92, 95% CI: 1.05-3.52 and adjusted Odds Ratio 1.93, 95% CI: 1.0.3-3.61, respectively). Conclusions: Patients who live in a densely populated area run a higher risk of MACE. SES is neither associated with worse outcomes after surgery nor with MACE in long-term follow-up.