Trends in patient characteristics and mortality among Medicare patients diagnosed with peripheral artery disease

Abstract

Introduction: Peripheral artery disease (PAD) is a well-described risk factor for mortality, but few studies have examined secular trends in mortality over time for patients with PAD. We characterized trends in mortality in patients with PAD in recent years among Medicare patients. Methods: We used Medicare claims to identify patients with a new diagnosis code for PAD between January 1, 2006 and December 31, 2018 using International Classification of Diseases (ICD) diagnosis codes. The primary outcome of interest was the 1-year all-cause age-adjusted mortality rate. Our secondary outcome was the 5-year all-cause mortality rate. Multivariable regression was used to identify factors which predict mortality at 1 year. Results: We identified 4,373,644 patients with a new diagnosis code for PAD during the study period. Between 2006 and 2018, 1-year all-cause age-adjusted mortality declined from 12.6% to 9.9% ( p < 0.001). One-year crude all-cause mortality also declined from 14.6% to 9.5% ( p < 0.001). Similar results were observed for 5-year age-adjusted mortality rates (40.9% to 35.2%, p < 0.001). Factors associated with increased risk of death at 1 year included age ⩾ 85 years (hazard ratio [HR] 3.030; 95% CI 3.008–3.053) and congestive heart failure (HR 1.86; 95% CI 1.85–1.88). Patients who were regularly dispensed statins, ace-inhibitors, beta-blockers, antithrombotic agents, and anticoagulants all had lower mortality (range OR 0.36; CI 0.35–0.37 for statins to OR 0.60; CI 0.59–0.61 for anticoagulants; all p < 0.001). Conclusion: Among US Medicare patients diagnosed with PAD between 2006 and 2019, 1-year age-adjusted mortality declined by 2.7%. This decline in mortality among PAD patients occurred in the context of a younger mean age of diagnosis of PAD and improved cardiovascular prevention therapy.