Comparative efficacy of zolpidem and temazepam in transient insomnia

yThis study compared hypnotic effects of zolpidem 10 mg, temazepam 15 mg an d placebo in healthy adults. Two factors expected to promote insomnia, the 'first night effect' and a 2-hour phase advance, were combined in a single night laboratory-based double-blinded protocol. This was a multi-center stu dy, with data collected in 13 sleep laboratories. Subjects with normal slee p histories and without prior sleep laboratory experience were randomly ass igned to treatment groups. Medications were administered 15 min before ligh ts out, with polysomnographic monitoring for 7.5 h. Subjective questionnair es and performance tests, digit symbol substitution test (DSST) and symbol copying test (SCT), were administered at study entry and after arising. 630 subjects completed the study and provided data analyzed using repeated mea sures ANOVAs. Neither agent significantly reduced objective sleep latency r elative to placebo. Zolpidem reduced awakenings and wake after sleep onset (WASO); temazepam did not. Both agents improved sleep efficiency and most s ubjective sleep measures relative to placebo, with zolpidem superior for fi ve of six subjective outcome measures compared to temazepam. SCT, morning s leepiness and morning concentration were not altered by any treatment. Zolp idem significantly reduced morning DSST performance; temazepam did not. Zol pidem 10 mg provided greater subjective hypnotic efficacy than temazepam 15 mg in this model of transient insomnia, with reduced polysomnographic awak enings and WASO. Impairment of DSST was seen with zolpidem but not temazepa m. Copyright (C) 2001 John Wiley & Sons, Ltd.