Editor's Choice - Impact of Comorbidity, Medication, and Gender on Amputation Rate Following Revascularisation for Chronic Limb Threatening Ischaemia

Abstract

Objective/background: Chronic limb threatening ischaemia (CLTI) has a high risk of amputation and mortality. Increased knowledge on how sex, comorbidities, and medication influence these outcomes after revascularisation may help optimise results and patient selection.

Methods: This population based observational cohort study included all individuals revascularised for CLTI in Sweden during a five year period (10,617 patients in total). Data were retrieved and merged from mandatory national healthcare registries, and specifics on amputations were validated with individual medical records.

Results: Mean age at revascularisation was 76.8 years. Median follow up was 2.7 years (range 0-6.6 years). Male sex (hazard ratio [HR] 1.20, 95% confidence interval [CI] 1.09-1.33), renal insufficiency (HR 1.57, 95% CI 1.32-1.87), diabetes (HR 1.45, 95% CI 1.32-1.60), and heart failure (HR 1.17, 95% CI 1.05-1.31) were independently associated with an increased amputation rate, whereas the use of statins (HR 0.71, 95% CI 0.64-0.78) and low dose acetylsalicylic acid (HR 0.77, 95% CI 0.70-0.86) were associated with a reduced amputation rate. For the combined end point of amputation or death, an association with increased rates was found for male sex (HR 1.25, 95% CI 1.18-1.32), renal insufficiency (HR 1.94, 95% CI 1.75-2.14), heart failure (HR 1.50, 95% CI 1.40-1.60), and diabetes (HR 1.31, 95% CI 1.23-1.38). The use of statins (HR 0.74, 95% CI 0.67-0.82) and low dose acetylsalicylic acid (HR 0.82, 95% CI 0.77-0.88]) were related to a reduced risk of amputation or death.

Conclusions: Renal insufficiency is the strongest independent risk factor for both amputation and amputation/death in revascularised CLTI patients, followed by diabetes and heart failure. Men with CLTI have worse outcomes than women. These results may help govern patient selection for revascularisation procedures. Statin and low dose acetylsalicylic acid are associated with an improved limb outcome. This underlines the importance of preventive medication to reduce general cardiovascular risk and increase limb salvage.

Keywords: Amputation; Arterial occlusive diseases; Atherosclerosis; Comorbidity; Mortality; Peripheral arterial disease.