Risk of traffic accident injury after a prescription for a benzodiazepine

The objective of this study was to assess the risk of hospitalization for injuries received in traffic accidents after a first prescription for benzodiazepines (BZD) was filled. Saskatchewan Health supplied study populations of 78,000 adults who received BZD hypnotics, 148,000 who received BZD anxiolytics, and 98,000 control subjects. These populations were monitored for 2 months after the index prescription fill-date for hospitalizations due to traffic accidents. Analysis showed an odds ratio (OR) of 3.9 (1.9 to 8.3) for persons taking BZD hypnotics and an OR of 2.5 (1.2 to 5.2) for those taking BZD anxiolytics, with regards to hospitalization due to traffic accidents within 4 weeks after the prescription was filled. Within 2 weeks after the prescription was filled, the OR had risen to 6.5 (1.9 to 22.4) for hypnotics and 5.6 (1.7 to 18.4) for anxiolytics. After 1 week, the ORs were even higher (9.1 and 13.5), but the confidence limits were wide. The highest risk groups were the youngest age group (20 to 39 years old) and males. From a public health view, the high ORs are of concern and action for prevention is needed.