A clinical study of the cognitive effects of benzodiazepines in psychogeriatric patients.

Previous studies have shown cognitive impairment in long-term benzodiazepine users compared to non-users. However, little is known about such effects in a population of geriatric psychiatry patients. The aim of this study was to identify differences between benzodiazepine users and non-users on standardized tests of the cognitive fields of learning and memory, executive functions and vigilance, at admittance to a department of geriatric psychiatry.Hopkins verbal learning test, Stroop test and digit vigilance test were performed in all patients. Test performances were compared between benzodiazepine users (n=168) and non-users (n=73). A multiple linear regression model was used, adjusting for different baseline characteristics (years of education, dementia and depression).No significant differences in test results were found between benzodiazepine users and non-users on 11 out of 12 cognitive tests results. On one of the 12 test results (time used on the digit vigilance test), benzodiazepine users showed better performance compared to non-users (ß=-0.20, p=0.032). This finding was not statistically significant after Bonferroni correction for multiple testing.This study of geriatric psychiatry benzodiazepine users did not reveal cognitive impairment compared to non-users on the cognitive areas tested. Other possible negative consequences of benzodiazepine use should, however, also be considered when prescribing drugs to older patients.