Patients may be asking about a recent study linking benzodiazepine use to Alzheimer’s disease (AD). Researchers from Canada performed a case-control study of nearly 1800 people with first-diagnosis AD along with nearly 7200 matched controls. Patients were followed for at least 6 years. Benzodiazepine ever-use was associated with a 50% increased risk of AD (adjusted odds ratio [OR], 1.51; 95% confidence interval [CI], 1.30-1.69). After adjustment for anxiety, depression, and insomnia, the OR was 1.43 (95% CI, 1.28-1.60) There was an increase in the association for exposure density, including number of prescribed daily doses and longer drug half-life. The authors conclude that benzodiazepine use is associated with increased risk of AD, with a stronger association with long-term use (BMJ2014;349:g5205). The authors addressed and feel they avoided “reverse causal bias” — the possibility that pre-dementia patients may be more likely to take a benzodiazepine due to anxiety or insomnia. They do not, however, suggest a mechanism whereby these drugs possibly cause permanent cognitive damage and suggest more research is needed.