Analysis of Preventive Effect of Bisphosphonate for Osteoporotic Fracture in Patients with Alzheimer's Disease and Patient Mortality.

: Alzheimer's disease (AD) is the most common neurodegenerative disease in the older adult population and is often associated with reduced physical activity. Reduced activity and mechanical loading subsequently reduce bone mineral density and increase risk of osteoporosis. Bisphosphonates (BPs) offer preventative effects on osteoporotic fractures in the general population, but their effects on patients with AD are less known. This study aimed to assess the impact of BPs on osteoporotic fractures and survival in patients with AD. : In this nationwide retrospective cohort study, 43,469 patients from the Korea National Health Insurance Service database between 2004 and 2018 were included. All patients were diagnosed with AD and subsequently diagnosed with osteoporosis. Continuous use of BPs was defined as having prescriptions for BP medications one year after the diagnosis of osteoporosis. Propensity score matching paired 12,519 BP users with 12,518 non-users for post-fracture survival analysis. : Continuous use of BPs showed a significant preventative effect on the Cox regression model [hazard ratio (HR), 0.890-0.895; < 0.001] but not on the logistic regression model. The occurrence of osteoporotic fractures in the hip or spine significantly increased the risk of death [hip, HR, 2.036; 95% confidence interval (CI), 1.789-2.316; < 0.001; spine, HR, 1.465; CI, 1.305-1.644; < 0.001]. : Continuous use of BPs was associated with reduced occurrence of osteoporotic fractures in patients with AD. Patients with AD showed significantly higher mortality rates after the occurrence of osteoporotic fractures. Further studies with detailed patient characteristics and compliance are warranted.