Risks and outcomes of critical limb ischemia in hemodialysis patients: a prospective cohort study

Background Peripheral arterial disease (PAD) is more common in patients receiving maintenance hemodialysis than in the general population. Critical limb ischemia (CLI), the most severe form of PAD, is associated with high amputation and mortality risk. However, few prospective studies are available evaluating this disease's presentation, risk factors and outcomes for patients receiving hemodialysis. Methods The Hsinchu VA study, a prospective multicentre study, investigated the impact of clinical factors on cardiovascular outcomes of patients receiving maintenance hemodialysis from January 2008 until December 2021. We evaluated the presentations and outcomes of patients with newly diagnosed PAD and the correlations of clinical variables with newly diagnosed CLI. Results Of 1136 study participants, 1038 had no PAD on enrolment. After a median follow-up period of 3.3 years, 128 had newly diagnosed PAD. Of these, 65 presented with CLI, and 25 underwent amputation or died from PAD. Patients presenting with CLI had more below-the-knee (52%) and multi-level (41%) disease, and completely occluded segments (41%), and higher risk for amputation or PAD-related death compared with patients without CLI (27.7% vs 9.5%, P = .01). After multivariate adjustment, disability, diabetes mellitus, current smoking and atrial fibrillation were significantly associated with newly diagnosed CLI. Conclusions Patients undergoing hemodialysis had higher rates of newly diagnosed CLI than the general population. Those with disabilities, diabetes mellitus, smoking and atrial fibrillation may require careful examination for PAD. Lay Summary Critical limb ischemia (CLI) is the most severe form of peripheral arterial disease (PAD), associated with high amputation and mortality risk. In the general population, most atherosclerotic risk factors are associated with PAD. However, there is limited understanding of the factors influencing PAD development in hemodialysis patients. Therefore, this study aimed to evaluate the presentation, risk factors and outcomes of incident CLI patients receiving maintenance hemodialysis. To the best of our knowledge, this is the first prospective cohort study to focus on the incidence, risk factors and outcomes of CLI in patients undergoing hemodialysis.