Risk of falling and hypnotic drugs: retrospective study of inpatients

Falls and related injuries remain a concern for patient safety in many hospitals and nursing care facilities. In particular, reports examining the relationship between accidents and drugs with a sedative effect have been increasing; however, the analysis of correlation between the background factors of fall accidents and the detailed therapeutic category of drugs is insufficient.

Our objective was to estimate fall risk following the administration of hypnotics in inpatients within an acute hospital. We assessed the relationship between falls and hypnotic drugs compared with other medicines.

An inpatient population-based study was carried out at Gunma University Hospital, where all inpatients admitted between 1 October and 31 December 2007 were included. Over a 3-month follow-up period, all reports of falling accidents from ward medical staff were investigated.

Falls occurred in 1.8% of males and 1.3% of females in the study population (n = 3,683). The mean age of patients who experienced falls (64.7 ± 19.5 years) was significantly higher than that of patients who did not (56.2 ± 20.2 years). Multivariate analysis revealed the following drugs as high-risk factors for falling: hypnotics (odds ratio [OR] 2.17, 95% CI 1.44-3.28), antiepileptics (OR 5.06, 95% CI 2.70-9.46), opioids (OR 3.91, 95% CI 2.16-7.10), anti-Alzheimer's (OR 5.74, 95% CI 1.62-20.3), anti-Parkinson's (OR 5.06, 95% CI 1.58-16.24), antidiabetics (OR 3.08, 95% CI 1.63-5.84), antihypertensives (OR 2.24, 95% CI 1.41-3.56), and antiarrhythmics (OR 2.82, 95% CI 1.36-5.86). Multivariate logistic regression analysis of hypnotics, brotizolam, zopiclone, and estazolam revealed a significant association with an increased risk of inpatient falling accidents, while zolpidem, triazolam, flunitrazepam, and nitrazepam did not.

The present findings suggest that the risk of falling accidents in hospitals differs according to the type of hypnotic drug administered. The appropriate selection of hypnotic drugs, therefore, might be important for reducing the number of patient falls.