An article published in the BMJ in September 2014 by De Gage et al examined the association between benzodiazepine use and the development of Alzheimer’s disease.

1796 patients from the Quebec health insurance programme database who had been followed up for at least six years prior to a first diagnosis of Alzheimer’s were matched with 7184 controls.

Risk of Alzheimer’s in benzodiazepine users was increased by 43-51%, and for use longer than three months, the risk increased with cumulative exposure. The association with Alzheimer’s was stronger for long-acting benzodiazepines than for short-acting ones. 

Adjustments for anxiety, depression and insomnia (possible prodromes of Alzheimer’s) did not alter the conclusions, but it is still possible that it is the prodromes that are associated with increased risk of dementia, rather than benzodiazepine use.

This study underscores the importance of using benzodiazepines judiciously, for the shortest possible time.