Exploring Fall‐Related Fracture Risk by Possible Fall‐Risk Increasing Drugs in Japanese Older Adults Using Municipal Linked Medical and Long‐Term Care Claim Data: A Nested Case‐Control and Case‐Crossover Study

Aim We examined the association between the use of fall‐risk‐increasing drugs (FRIDs) and other medications, and the risk of fall‐related fractures in Japanese community‐dwelling older adults. Methods We used linked medical and long‐term care insurance claims data from Tsukuba City, Japan (2014–2019). Two designs were applied: a nested case‐control study comparing 1957 fracture cases to 7828 matched controls for long term use, and a case‐crossover (CCO) study for short term use including 1840 fracture cases with up to 180 days of follow‐up, in which the case period (1–30 days prior to the index date) was compared with control periods (five 30‐day periods up to 180 days prior). Medication exposure included FRIDs and other medications. The outcome was non‐vertebral fractures defined by diagnostic codes, imaging, and surgical or procedural treatment. Conditional logistic regression was used to calculate odds ratios (ORs). Results In the nested case‐control study, the adjusted ORs (fracture cases vs. controls) for use of calcium channel blockers (1.16, 95% confidence interval [CI]: 1.05–1.33) and other anti‐dementia drugs (1.62, 95% CI: 1.11–2.37) were significantly elevated. In the CCO study, the unadjusted ORs (case period vs. control periods) for antipsychotics (3.65, 95% CI: 1.78–7.49), opioids (1.53, 95% CI: 1.05–2.22), anticonvulsants (1.86, 95% CI: 1.15–2.99), and NSAIDs (1.46, 95% CI: 1.18–1.71) were significantly elevated. Conclusion Long‐ and short‐term use of specific medications is associated with increased fracture risk in older adults. Therefore, attention should be paid to prescription of these drugs in older adults.