The Impact of Follow-Up on Mortality in Chronic Limb-Threatening Ischemia

Background: Chronic limb-threatening ischemia (CLTI) is associated with high morbidity and mortality. As such, close follow-up is recommended to ensure patency of revascularization, limb viability, and optimization of cardiovascular risk factors. This study aimed to test the association between follow-up adherence and mortality, and to identify risk factors for nonadherence with recommended vascular follow-up. Methods: All patients hospitalized from 2019 to 2023 with infrainguinal CLTI and at least 30 days of posthospitalization survival were included. Patients were stratified based on adherence with any outpatient vascular follow-up within 1 year defined as any outpatient visit conducted after the index hospitalization in which CLTI of the index limb was addressed. The primary endpoint was 1-year mortality and risk factors for follow-up nonadherence were assessed to identify targets for improvement. Multivariable models adjusted for other relevant contributors to mortality including age, clinical comorbidities, medical therapies, and anatomic/clinical limb severity among others. Additional sensitivity analyses were conducted using various definitions of follow-up adherence to enhance reliability of the findings. Results: A total of 131 patients with a median age of 73 years were included. A majority had tissue loss (97, 74.1%), 118 (90.1%) underwent index revascularization and 13 (9.9%) received no intervention due to nonsalvageable disease or patient preference. The overall 1-year mortality rate was 19.8% and follow-up adherence was 83.2%. Nonadherence with vascular follow-up was associated with greater 1-year mortality (40.9% vs. 15.6%, odds ratio (OR) 6.67, P = 0.005), a finding which persisted when all definitions of follow-up were tested. Risk factors for follow-up nonadherence include transfer from another institution (30.2% vs. 10.2%, OR 3.704, P = 0.014) and lack of a primary care provider (66.7% vs. 11.8%, OR 14.603, P < 0.001). Conclusions: Nonadherence with vascular follow-up is associated with higher 1-year mortality among patients with CLTI. Improved referral of CLTI patients to a vascular surgeon in the outpatient setting before the need for urgent interhospital transfer as well as care coordination through a primary care provider may help improve adherence with vascular follow-up.