Cardio-Neurovascular Multimorbidity in Diabetes: Real-World Overlap of Heart Failure, Peripheral Neuropathy, and Lower-Limb Amputation

Background: Diabetes mellitus is frequently complicated by cardiovascular, neurological, and limb-threatening conditions, yet these complications are often evaluated separately. Heart failure, peripheral neuropathy, and lower-limb amputation may coexist in patients with advanced diabetes and may define a clinically severe cardio-neurovascular multimorbidity phenotype. This study evaluated the real-world overlap between these complications. Methods: This retrospective hospital-based study used four routinely generated patient-level exports from the electronic diabetes registry/clinical information system of the Clinical County Emergency Hospital Bihor, Oradea, Romania. The primary cohort comprised 2246 unique patients with diabetes and a recorded heart failure diagnosis; linked exports identified peripheral neuropathy and below- or above-ankle amputation. Results: Peripheral neuropathy was documented in 1028 patients (45.8%). Patients with neuropathy were older (median 70 [IQR 63–76] vs. 67 [IQR 59–73] years, p < 0.001) and had longer diabetes duration (15 [IQR 9–21] vs. 6 [IQR 1–11] years, p < 0.001) than patients without neuropathy. Any lower-limb amputation occurred in 35 patients (1.6%) and was more frequent among patients with neuropathy than among those without neuropathy (2.6% vs. 0.7%, p < 0.001). In the adjusted analysis, male sex, diabetes duration, and insulin therapy were independently associated with lower-limb amputation, whereas the association with neuropathy was attenuated. Conclusions: In this hospital-based retrospective cohort, peripheral neuropathy was common and identified a subgroup with longer-standing diabetes, more intensive therapy, and greater amputation burden. The findings indicate associations within a selected clinical population and should not be interpreted as causal or population-based estimates.