Demographic and Clinical Characteristics of Patients With Charcot Neuro‐Osteoarthropathy in People With Diabetes Mellitus in Six Countries: A Multicenter Observational Study From 1996 to 2022

<b>Aim:</b> To describe the demographic and clinical characteristics of patients with Charcot neuro-osteoarthropathy (CNO) and to examine for differences between participants with Type 1 diabetes mellitus (DM) (T1DM) and Type 2 diabetes mellitus (T2DM). <b>Materials and Methods:</b> Multicenter observational study in eight diabetic foot clinics in six countries between January 1, 1996, and December 31, 2022. Demographic, clinical, and laboratory parameters were obtained from the medical records. Analyses were performed using parametric or nonparametric statistical tests for variables with normally or nonnormally distributed values, respectively. Comparisons of the qualitative data were performed using the chi-square test. <b>Results:</b> Seven hundred seventy-four patients with DM and CNO were included. The mean age at diagnosis of CNO was 54.5 ± 11.7 years, and the median (interquartile range (IQR)) diabetes duration at diagnosis of CNO was 15 (10-22) years. Among participants, 71.8% (<i>n</i> = 546) were male and 83.2% (<i>n</i> = 634) had T2DM. Neuropathy was present in 91.7% (<i>n</i> = 688), retinopathy in 60.2% (<i>n</i> = 452), and nephropathy in 45.2% (<i>n</i> = 337). Subjects with T1DM, compared to T2DM, were diagnosed with CNO at a younger age (46.9 ± 11.0 vs. 57.9 ± 10.2 years, <i>p</i> < 0.001), had longer diabetes duration (median value (IQR): 29.0 (21.0-38.0) vs. 14.0 (8.0-20.0) years, <i>p</i> < 0.001), and had more often microvascular complications (neuropathy, 95.2% in T1DM vs. 87.4% in T2DM, <i>p</i> = 0.006; retinopathy, 83.3% vs. 55.4%, <i>p</i> < 0.001; and nephropathy 67.5% vs. 40.5%, <i>p</i> < 0.001). <b>Conclusions:</b> CNO is predominant in males, occurs in long-standing DM, and is often accompanied by microvascular complications. People with T1DM, compared to those with T2DM, are affected at a younger age, have longer diabetes duration, and have more often microvascular complications.