Neuropathy Screening for Patients with Peripheral Vascular Disease Helps to Identify Those at an Increased Risk of Amputation, Revascularization, and Death

Abstract

Peripheral neuropathy is associated with amputation risk among patients with diabetes mellitus and chronic limb-threatening ischemia (CLTI). Detection of peripheral neuropathy may help identify those who are at an increased risk, but the predictive ability of the screening tool used in patients with peripheral arterial disease (PAD) needs to be more clearly defined. Patients referred to vascular surgery clinic for PAD were recruited from a single center. Exclusion criteria were a documented history of neuropathy or prior lower limb amputation. Screening utilized the Michigan Neuropathy Screening Instrument (MNSI). Scores >2.5 were considered abnormal and scores >4 were considered positive for peripheral neuropathy. Limb-specific outcomes of amputation and revascularization as well as a composite outcome including death were modeled using time to event analysis. 86 patients were recruited. Mean age was 67±10.2years, 30% were women, 24% were black. Mean ankle-brachial index was 0.74±0.3. PAD symptoms at initial evaluation were claudication in 52% of patients and CLTI in 38% of patients. Neuropathy was present in 20% of the cohort with a significantly higher proportion in diabetics (34% vs. 3%; P=0.0009). Neuropathy was more common in patients with CLTI compared to claudicants (36% vs. 9%; P=0.011). Forty patients (47%) reached the composite outcome of amputation, revascularization, or death with a median time to event of 16months. Abnormal MNSI examination was significantly associated with the increased risk of the composite outcome (hazard ratio=3.19; P 0.0005). A significant proportion of patients presenting to vascular specialists for PAD have undiagnosed neuropathy. Patients with PAD and neuropathy have an increased risk of amputation, revascularization, and death. Expanding neuropathy screening in vascular surgery clinic visits may help to identify patients at higher risk.