Table 3: Memory impairment outcomes in randomized controlled trials evaluating benzodiazepines for the treatment of insomnia
Study Study quality* n Mean age (and SD) Length of treatment; d Benzodiazepine Comparison group(s) Outcome measure Summary of results

Bixler et al69 4 18 37 (3.5) 8 (after 4 d run-in) Temazepam, 30 mg
Triazolam, 0.5 mg
Placebo Immediate memory and delayed memory tests, patient-reported memory impairment/amnesia Triazolam group, compared with placebo and temazepam, displayed delayed recall and daytime memory impairment/amnesia (40% rate of latter)
Mamelak et al.80 2 36 60–72 14 + 2 for withdrawal Flurazepam, 15 mg Placebo Digit symbol immediate memory, digit symbol delayed memory, serial learning test Flurazepam group significantly worse with immediate and delayed memory and serial learning
Ponciano et al.75 3 26 30 (9) 28 Flurazepam, 30 mg Placebo, zopiclone, 7.5 mg Digit-span technique (short-term memory) No significant difference in responses

*Quality score based on randomization, double blinding, controlling for baseline differences and > 80% follow-up of patients; maximum score = 5.
n = number of subjects.