Benzodiazepine-induced reduction in activity mirrors decrements in cognitive and psychomotor performance

✍ Scribed by Jean Dawson; Julia Boyle; Neil Stanley; Sigurd Johnsen; Ian Hindmarch; Debra J. Skene

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 125 KB
• Volume: 23
• Category: Article
• ISSN: 0885-6222
• DOI: 10.1002/hup.961

✦ Synopsis

Abstract

Objective

To assess whether actigraphy is sensitive to benzodiazepine‐induced changes in cognitive and psychomotor performance and sleep.

Methods

Healthy young volunteers (n = 23; 11 males), were randomised to a double‐blind, placebo‐controlled, crossover trial. Actigraphy was used to record motor activity continuously. Following dosing at 18.00 h with 2.5 mg lorazepam (LZP), psychomotor and cognitive assessments were made at hourly intervals post‐dose for 4 h and after sleep at 14.5 h post‐dose.

Results

Activity levels were significantly reduced after LZP for 5 h post‐dose (p = 0.0104), during sleep (5–13 h) (p < 0.02) and the following morning, 13–14.5 h post‐dose (p < 0.02). At the same time cognitive and psychomotor performance was also significantly impaired (p < 0.05). LZP also significantly increased actigraphic sleep efficiency and sleep per cent (p < 0.02).

Conclusion

This study showed that activity levels were significantly reduced following dosing with a benzodiazepine and these changes coincided with impairment of cognitive and psychomotor performance. Actigraphy, therefore, appears to be able to reflect the psychopharmacological effects of a benzodiazepine in changes in daytime function and nocturnal behaviour, which, without waking the subject, is beyond the power of conventional psychometrics. Copyright © 2008 John Wiley & Sons, Ltd.