Insomnia and hypnotic use, recorded in the minimum data set, as predictors of falls and hip fractures in Michigan nursing homes

Abstract

Objectives: To examine the relationship between insomnia, hypnotic use, falls, and hip fractures in older people.

Design: Secondary analysis of a large, longitudinal, assessment database.

Setting: Four hundred thirty-seven nursing homes in Michigan.

Participants: Residents aged 65 and older in 2001 with a baseline Minimum Data Set assessment and a follow-up 150 to 210 days later.

Measurements: Logistic regression modeled any follow-up report of fall or hip fracture. Predictors were baseline reports of insomnia (previous month) and use of hypnotics (previous week). Potential confounds taken into account included standard measures of functional status, cognitive status, intensity of resource utilization, proximity to death, illness burden, number of medications, emergency room visits, nursing home new admission, age, and sex.

Results: In 34,163 nursing home residents (76% women, mean age+/-standard deviation 84+/-8), hypnotic use did not predict falls (adjusted odds ratio (AOR)=1.13, 95% confidence interval (CI)=0.98, 1.30). In contrast, insomnia did predict future falls (AOR=1.52, 95% CI=1.38, 1.66). Untreated insomnia (AOR=1.55, 95% CI=1.41, 1.71) and hypnotic-treated (unresponsive) insomnia (AOR=1.32, 95% CI=1.02, 1.70) predicted more falls than did the absence of insomnia. After adjustment for confounding variables, insomnia and hypnotic use were not associated with subsequent hip fracture.

Conclusion: In elderly nursing home residents, insomnia, but not hypnotic use, is associated with a greater risk of subsequent falls. Future studies will need to confirm these findings and determine whether appropriate hypnotic use can protect against future falls.