Risk of falls or fall-related injuries associated with potentially inappropriate medication use among older adults with dementia.

Background: Potentially inappropriate medications (PIMs) are prevalent in older adults with dementia and subsequent falls or fall-related injuries. The present study determined the risk of falls or fall-related injuries associated with PIM use in older adults with dementia.

Methods: The National Health Insurance Service-Elderly Cohort Database 2.0 (NHIS-ECDB 2.0) was used for this self-controlled case series (SCCS) study. This study included 1430 participants who went through exposure and non-exposure periods of PIM application among patients with dementia and experienced outcome events of falls or fall-related injuries between January 2016 and December 2019. The incidence of falls or fall-related injuries during the exposure and post-exposure periods was compared with that during the non-exposure period. Beers Criteria were used to define PIMs in patients with dementia. Negative binomial regression was conducted. The incidence rate ratio (IRR) was used to determine the risk of falls or fall-related injuries.

Results: During the exposure periods in which falls or fall-related injuries occurred, the mean number of PIMs among patients with dementia was 3.76 (SD = 2.99), and the most commonly used PIMs among patients with dementia were first-generation antihistamines (n = 283; 59.1%). Compared to the non-exposure period, the adjusted IRR during the exposure period was 1.57 (95% CI = 1.39-1.76). The risk of falls or fall-related injuries was increased when PIM use in patients with dementia was initiated (1-14 days: IRR = 2.76, 95% CI = 2.31-3.28; 15-28 days: IRR = 1.95, 95% CI = 1.48-2.56; ≥ 29 days: IRR = 1.17, 95% CI = 1.01-1.35). Especially, an increased risk of falls or fall-related injuries was associated with greater PIM use among patients with dementia.

Conclusion: Among older adults with dementia, PIMs significantly increase the risk of falls and fall-related injuries. Therefore, strategies should be developed to manage PIM prescriptions in patients with dementia to prevent falls.