Living in a medically underserved county is an independent risk factor for major limb amputation

Abstract

Despite an increase in the incidence of hospital admissions for comorbid conditions, such as diabetes, the incidence of major limb amputation in North Carolina has decreased. The decline in amputation rate has not been uniformly realized across the state. The objective of this study was to determine the association between major vascular limb amputation and living in an underserved county in North Carolina. We analyzed discharges aged 18 to 100 years old with a peripheral arterial disease (PAD)-related admission from the North Carolina Inpatient Discharge Database from 2006 to 2009. Medically underserved counties are defined by the United States Health Resources and Services Administration as having too few primary care providers, high infant mortality, high poverty, or high elderly population. The association between major amputation prevalence and medically underserved counties was calculated using a binomial regression model adjusted for sex, age, diabetes, end-stage renal disease, PAD, and critical limb ischemia. Each confounder was assessed using backward elimination modeling. Among the 222,920 discharges with a PAD-related hospital admission from 2006 to 2009, 8601 (3.9%) were from medically underserved counties. There were 7328 major amputations. The adjusted prevalence odds ratio of the association between underserved counties and major vascular limb amputation is 1.29 (95% confidence interval, 1.16-1.44). None of the confounders significantly affected the association between underserved counties and number of amputations. Living in an underserved county in North Carolina is associated with a 29% increase in the odds of undergoing major limb amputation. Gender, age, and comorbidities, including diabetes, end-stage renal disease, and PAD, do not significantly affect the relationship.