Cognitive impairment in long-term benzodiazepine users.

In view of the very extensive and often prolonged use of benzodiazepines in therapeutic practice, this study was designed to investigate whether or not cognitive ability is impaired in long-term benzodiazepine users, and to determine the nature and extent of any deficit. Fifty patients currently taking benzodiazepines for at least one year, thirty-four who had stopped taking benzodiazepines, and a matched control group of subjects who had never taken benzodiazepines or who had taken benzodiazepines in the past for less than one year were administered a battery of neuropsychological tests designed to measure a wide range of cognitive functions. It was found that patients taking high doses of benzodiazepines for long periods of time perform poorly on tasks involving visual-spatial ability and sustained attention. This is consistent with deficits in posterior cortical cognitive function.