Vascular Surgery Workforce Reductions Decrease Ambulatory Care Delivery for Carotid and Peripheral Arterial Disease

Despite an established vascular surgery workforce (VSW) shortage, it is unclear whether reductions in VSW stimulate compensatory care from other providers. We use measures of ambulatory care dispersion (ACD) to compare diversity and density of providers managing early vascular disease based on state-level changes in VSW. The Truven Health Marketscan Commercial Claims and Encounters Database with Medicare Supplement, a private claims database, was queried for billing vascular surgeons from 2007 to 2016. State-level changes in VSW were calculated as the percentage difference in vascular surgeons (VS) per 100,000 beneficiaries from 2007 through 2011 to 2012 through 2016. To assess ACD, patients diagnosed with asymptomatic carotid stenosis, intact abdominal aortic aneurysm (AAA), or intermittent claudication (IC) in 2012 were longitudinally followed until 2016 using two metrics: provider count, which measures care diversity, and Breslau's Usual Provider of Care (UPC) which measures concentration of care for the specified diagnoses. Generalized linear models adjusting for age, sex, and comorbidities assessed the impact of state-level VSW changes on ACD. Absolute VSW ranged from 0.41 VS per 100,000 beneficiaries in Nevada to 7.16 in Hawaii (Fig 1), with VSW changes spanning a 229% reduction in Montana to a 67.9% increase in Louisiana (Fig 2). In a generalized linear model of 6905 patients with IC adjusted for age, sex, and comorbidity, increasing VSW was independently associated with increased provider count (incidence rate ratio [IRR], 1.08; P < .01), and reduced care concentration among providers (IRR, 0.97; P < .01). In 11,564 patients with asymptomatic carotid stenosis, increasing VSW was independently associated with increased provider count (IRR, 1.08; P < .01) and reduced care concentration among providers (IRR, 0.97; P < .01). VSW changes did not influence ACD measures in 1674 intact patients with AAA. In a trends analysis of the VSW in a large national claims database, the absolute number of VS per 100,000 beneficiaries varied from 0.41 to 7.16. Most states had VSW reduction over the study period, with highly populous states, including Texas and California, experiencing greater than 50% decrease from 2007 to 2016. Patients with asymptomatic carotid stenosis or IC who lived in states with VSW reduction experienced reduced ACD, and thus saw fewer providers with less frequency. This suggests that VSW shortfalls are not easily compensated for by other medical and surgical providers. Strategies to augment VSW are imperative to ensuring patients are receiving comprehensive vascular care. Future work will study the impact of a declining VSW on clinical outcomes of chronic vascular disease.Fig 2View Large Image Figure ViewerDownload Hi-res image Download (PPT)