Spinal cord injury and Alzheimer's disease risk: a population-based, retrospective cohort study

Study design Propensity score-matched, retrospective cohort study. Objectives To determine the risk of developing Alzheimer's disease (AD) in patients with spinal cord injury (SCI). Setting The present study used Taiwan's National Health Insurance Research Database. Methods A total of 9257 patients who had >= 2 ambulatory visits with a diagnosis of SCI in 2001 were included in the SCI group. The non-SCI group consisted of 37,028 propensity score-matched patients without a diagnosis of SCI. The cumulative incidence of AD was estimated for each of the two patient groups using the Kaplan-Meier method. Stratified Cox proportional hazard regression was then employed to assess the influence of SCI on the risk of AD. Results During the follow-up period, 25 subjects in the SCI group and 57 in the non-SCI group developed AD. The cumulative incidence of AD in the SCI group was higher than in the non-SCI group (P = 0.0168); and the hazard ratio of AD for the SCI group, as compared to the non-SCI group, was 1.71 (95% CI 1.06-2.76, P = 0.0273). Conclusions This study suggests that patients with SCI have an increased risk of developing AD.