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

Abstract

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.