Alzheimer’s disease and related syndromes and hospitalization: a nationwide 5‐year longitudinal study

Abstract

Background To study the association between Alzheimer's disease and Related Syndromes (ADRS) and the incidence of short‐stay hospitalizations from the year before (Y‐1) to 4 years after (Y1 to Y4) ADRS identification in the healthcare system. Methods Among all beneficiaries of the French health insurance general scheme aged 40 or more, those with an incident ADRS in 2011, identified through long‐term disease registry, hospitalization diagnoses, or ADRS‐specific drug delivery, were matched with beneficiaries without an ADRS of same age, gender, and residence area. The annual incidence rates of all‐causes hospitalizations (excluding those with a diagnosis code of ADRS) were compared between individuals with or without an ADRS using incidence ratios (IRs), globally and by age, gender, deprivation index and modified Charlson score. We also studied cause‐specific hospitalizations, using patient’s diagnoses and procedures codes. Results 90871 subjects with an ADRS and 90871 without were included (mean age: 79.6, 66% females). From Y‐1 to Y4, incidence rates were significantly higher in subjects with an ADRS than in those without, for all‐causes hospitalization (IR(Y_‐1)=1.73 [95% confidence interval: 1.71‐1.75]; IR(Y₄)=1.37 [1.35‐1.39]), hospitalizations for social reasons (IR(Y_‐1)=4.28; IR(Y₄)=2.70), fall (IR(Y_‐1)=5.36; IR(Y₄)=2.59), injury (IR(Y_‐1)=2.71; IR(Y₄)=2.09), and infection (IR(Y_‐1)=2.04; IR(Y₄)=2.07). The inverse was observed for hospitalizations for cataract surgery (IR(Y_‐1)=0.73; IR(Y₄)=0.51) or total hip prosthesis after 2 years (IR(Y₄)=0.72). Conclusions Incident ADRS cases were associated with a higher incidence of hospitalizations, but these subjects used less frequently some non‐emergency common surgeries. Future studies need to assess the clinical impact of these differences.