Retrospective study of cardiovascular disease risk factors among a cohort of combat veterans with lower limb amputation

Abstract

Introduction: Previous studies have shown that veterans with lower limb amputation have a higher risk for cardiovascular disease (CVD) compared with population-based controls. American veterans who have served in Iraq and Afghanistan with lower limb amputation may be at a similarly higher risk. Patients and methods: The Navel Health Research Center (NHRC) maintains the Expeditionary Medical Encounter Database (EMED) of military personnel who have sustained combat limb amputation or serious limb injury during the conflicts in Iraq and Afghanistan. Department of Veterans Affairs data from 2003 to April 2015 was used to analyze CVD risk factors in this cohort. Veterans with either unilateral (n=442) or bilateral (n=146) lower limb amputation were compared to those with serious lower limb trauma without amputation (n=184). Multivariate regression was used to measure associations between lower limb amputation and CVD risk factors over an average of 8 years of follow-up. Outcomes included mean arterial pressure (MAP), low-density lipoprotein, high-density lipoprotein (HDL), and serum triglycerides (TG). Results: Compared with the limb injury group, those with unilateral lower limb amputation had significantly lower HDL (p<0.05) and higher TG (p<0.05). Those with bilateral lower limb amputation had significantly higher MAP (p<0.05), lower HDL (p<0.01), and higher TG (p<0.001). The prevalence of metabolic syndrome, defined as type 2 diabetes or a constellation of blood pressure and lipid changes consistent with metabolic syndrome, was 8.7%, 14.9%, and 21.9% for limb injury, unilateral amputation, and bilateral amputation groups, respectively. Veterans with bilateral lower limb amputation had a 2.25-increased odds ratio (95% confidence interval 1.19-5.05) of type 2 diabetes or blood pressure and lipid changes consistent with metabolic syndrome compared to those with limb injury. Conclusions: Results suggest that veterans with lower limb amputation have a higher risk for metabolic syndrome. Primary care interventions to manage weight, blood pressure, and lipid levels are fundamental in order to reduce cardiac risk in this relatively young cohort.