NEW EVIDENCE ON BENZODIAZEPINE USE AND FALLS - THE TIME FACTOR

The objectives of this prospective study were to calculate incidence r ates for fall-related hospitalization, to compare the effect of risk f actors among benzodiazepine (BZD) users and unexposed controls, and to examine variations in risks according to length of time following a B ZD prescription. Data were derived from Saskatchewan Health linked dat a bases, leading to information on 468 hospitalizations for injury due to falls among a study population of 321422. Incidence rates per 1000 0 within 28 days of the prescription fill date were 26.2, 12.1 and 9.0 for BZD sedative users, BZD tranquillizer users and for unexposed con trols, respectively. Incidence rates increased with age, and were high er for women than for men. Results from multivariate logistic regressi on models also showed a greater risk of falling for BZD users but the odds ratio was higher for men than for women. A history of treatment f or alcohol abuse was a very strong risk factor for falls among both me n (odds ratio, 10.7) and women (odds ratio, 4.3). The highest risk of serious injury due to falls was within 15 days of filling the prescrip tion, with an odds ratio of 3.6 for BZD sedatives and 2.6 for BZD tran quillizers. Risk decreased with further increase of time after the BZD fill date. For the individual BZD, flurazepam and triazolam showed th e highest increase in risk with odds ratios of 3.4 and 2.7, respective ly, while oxazepam, lorazepam and diazepam showed odds ratios of 2.2, 2.0 and 1.8 (all odds ratios mentioned are statistically significant a t p < 0.05).