Absence of Tendon Reflexes as a Predictor of Diabetic Retinopathy: A Retrospective Cohort Study in Japan

Background/Objective: This study investigated the association between tendon reflexes (Achilles and patellar) and the development of diabetic retinopathy (DR) in patients with type 2 diabetes (T2D). Methods: This single-center retrospective cohort study enrolled patients with T2D. The primary outcome was the development of DR. Tendon reflex findings were classified into four groups (normal, decreased, absent, and not examined). A regression analysis using a Cox proportional hazard model was performed to evaluate the association between tendon reflex findings and the outcome. Results: A total of 1172 patients were included in the primary outcome analysis. The median follow-up period was 4.3 years, and 271 experienced DR development. In the multivariate analysis, an absent Achilles tendon reflex (hazard ratio HR, 1.52; 95% confidence interval CI: 1.01–2.27) and an absent patellar tendon reflex (HR: 1.89, 95% CI: 1.18–3.03) were independently associated with DR development. Conclusions: The absence of the Achilles and patellar tendon reflexes may serve as risk markers for DR development. Clinical Practice Implications: Non-invasive assessment of tendon reflexes may serve as an adjunctive tool to identify patients with T2D at high risk for future DR, enabling timely ophthalmologic referral and targeted management.