Osteoporosis and risk of dementia among older adults: a population‑based cohort study

Evidence on the association between osteoporosis and dementia is not fully clear. This study aimed to investigate the potential association between osteoporosis and the subsequent risk of dementia among older adults. We performed a cohort study of 176 150 community-dwelling older adults aged ≥65 years and free of cognitive impairment between 2018 and 2022 using integrated healthcare data from Shenzhen, China. Diagnoses of osteoporosis, osteoporotic fractures, and dementia were identified through linked outpatient and inpatient medical records and death registration records. Multivariate Cox proportional hazards models were used to estimate the adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of incident dementia associated with osteoporosis and osteoporotic fractures. The mean (SD) age of the total study population was 70.7 (5.4) years, and 9 605 had a previous diagnosis of osteoporosis. Over a median follow-up of 2.2 (IQR: 1.8-4.3, maximum: 5.5) years, corresponding to 505 423 person-years at risk, 1 367 incident all-cause dementia cases, including 617 Alzheimer's disease and 298 vascular dementia cases, occurred. Physician-diagnosed osteoporosis was associated with a higher risk of all-cause dementia (HR: 1.80, 95% CI: 1.53-2.12). The increased dementia risk tended to be more prominent among patients with osteoporotic fractures (HR: 2.43, 95% CI: 1.83-3.23) than those without (HR: 1.63, 95% CI: 1.35-1.97). Results were similar for Alzheimer's disease and vascular dementia. This study provides evidence that older adults with osteoporosis, especially those with osteoporotic fractures, have an elevated risk of incident dementia. Effective prevention and management of osteoporosis among the older population may be promising to mitigate the dual burden of osteoporosis and dementia.