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.

Increased Risk of Acute Cholecystitis in Patients With Spinal Cord Injury: A Nationwide Population-Based Cohort Study.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To evaluate the risk of acute cholecystitis (AC) in patients with spinal cord injury (SCI) based on a nationwide sample. SUMMARY OF BACKGROUND DATA: Prior research evaluating the risk of AC in patients with SCI is limited. Moreover, since most previous studies on the association between AC and SCI used case-series designs, little is known about the relative risk of SCI patients developing AC from a longitudinal follow-up, compared with individuals without SCI. METHODS: We used the data from Taiwan's National Health Insurance Research Database. The SCI group consisted of 11,523 patients with SCI aged between 20 and 90 years. Propensity score matching procedure was employed to minimize potential confounding effects arising from the imbalance in the baseline characteristics. A total of 23,046 propensity score-matched patients without SCI were enrolled in the non-SCI group. We compared the incidence of AC between these two groups, and assessed the impact of SCI on the risk of developing AC. RESULTS: In the SCI and non-SCI groups, the respective incidence rates of AC were 36.9 (95% confidence interval [CI], 30.0-44.8) and 25.2 (95% CI, 21.2-29.8) per 10,000 person-years. As compared with the non-SCI group, the hazard ratio for the SCI group of AC was 1.71 (95% CI, 1.22-2.41, P = 0.0018); and the cumulative incidence of AC of the SCI group was higher than that of the non-SCI group (P = 0.0036). CONCLUSION: This population-based cohort study showed that there was an increased risk of AC in patients with SCI. LEVEL OF EVIDENCE: 3.