Diabetic Neuropathy Is Associated With Lower Bone Mineral Density and Higher Fall Risk in Young Elderly Adults With Type 2 Diabetes

Background and aim: Diabetic neuropathy (DN) is a recognised risk factor for fragility fractures. However, the mechanisms linking DN, bone health, and falling risk remain unclear. We aimed to assess bone health and risk of falls, with their contributing factors, in young elderly patients with type 2 diabetes (T2D) and mild-to-moderate DN. Methods: We enrolled 144 subjects with T2D, excluding those with severe DN (neuropathy disability score -NDS- >= 9) or fracture history. Clinical and biochemical data were collected, including surrogate markers of insulin resistance, such as the triglycerides/HDL (TG/HDL) ratio and triglycerides/glucose (TyG) index. Bone mineral density (BMD) and trabecular bone score (TBS) were evaluated using DXA scans. Falls were self-recorded prospectively over 4 years using diaries. Results: Subjects with DN (27%) had higher BMI (p = 0.036), fasting blood glucose (p = 0.04), serum triglycerides (p = 0.016), TG/HDL ratio (p = 0.012) and TyG index (p = 0.003) compared with those without DN. After adjustment for gender, age, BMI, HbA1c, TyG index and TG/HDL ratio, subjects with DN showed significantly lower BMD at the femoral neck (0.702 [0.638-0.850] g/cm(2) vs. 0.789 [0.717-0.860] g/cm(2), p = 0.015) and total femur (0.890 [0.820-1.055] g/cm(2) vs. 0.983 [0.889-1.076] g/cm(2), p = 0.027). No differences were observed in spine BMD or TBS. However, TBS was negatively correlated with the TG/HDL ratio (r = -0.215, p = 0.013) and visceral adipose tissue (r = -0.310, p < 0.001). After 4 years of follow-up, subjects with painful neuropathy at baseline had a higher rate of falls (p = 0.011). Conclusion: DN is associated with decreased BMD and increased risk of falls. Among factors associated with DN, insulin resistance was also associated with decreased bone quality.