Cardiovascular outcomes in patients with peripheral arterial disease as an initial or subsequent manifestation of atherosclerotic disease: Results from a Swedish nationwide study

Objective: Long-term progression of peripheral arterial disease (PAD) as initial manifestation of atherosclerotic arterial disease is not well described. Cardiovascular (CV) risk was examined in different PAD populations diagnosed in a hospital setting in Sweden. Methods: Data for this retrospective cohort study were retrieved by linking data on morbidity, medication use, and mortality from Swedish national registries. Primary CV outcome was a composite of myocardial infarction, ischemic stroke (IS), and CV death. Kaplan-Meier analysis and Cox proportional hazards modeling was used for describing risk and relative risk. Results: Of 66,189 patients with an incident PAD diagnosis (2006-2013), 40,136 had primary PAD, 16,786 had PAD _ coronary heart disease (CHD), 5803 had PAD _IS, and 3464 had PAD _IS _CHD. One-year cumulative incidence rates of major CV events for the groups were 12%, 21%, 29%, and 34%, respectively. Corresponding numbers for 1-year all-cause death were 16%, 22%, 33%, and 35%. Compared with the primary PAD population, the relative risk increase for CV events was highest in patients with PAD _IS _CHD (hazard ratio [HR], 2.01), followed by PAD _IS (HR, 1.87) and PAD _ CHD (HR, 1.42). Despite being younger, the primary PAD population was less intensively treated with secondary preventive drug therapy. Conclusions: PAD as initial manifestation of atherosclerotic disease diagnosed in a hospital-based setting conferred a high risk: one in eight patients experienced a major CV event and one in six patients died within 1 year. Despite younger age and substantial risk of future major CV events, patients with primary PAD received less intensive secondary preventive drug therapy.