The Time of Day Sleepiness Scale to assess differential levels of sleepiness across the day.

OBJECTIVE: The study evaluated the Time of Day Sleepiness Scale (ToDSS) to determine subjective estimates of sleepiness in the morning, afternoon, and evening. Scores on the ToDSS were compared to the Epworth Sleepiness Scale (ESS). The ToDSS was evaluated on three cohorts of patients at a sleep medicine clinic. METHOD: The items of the ToDSS are modified from the ESS to enable subjective assessment in the morning (before noon), afternoon (noon to 1800 h), and evening (after 1800 h). The scale takes about 5 min to complete. For each item, patients provide an estimate of their level of sleepiness in three separate columns, each indicating the time of day (morning, afternoon, and evening). RESULTS: Each ToDSS score evidenced a one factor structure. The ToDSS enabled the assessment of differential levels of sleepiness across the day among several cohorts, with scores increasing in the afternoon and evening. The ESS and each score of the ToDSS demonstrated high correlations. Lower subjective estimates of sleepiness were documented after treatment with continuous positive airway pressure. CONCLUSIONS: The ToDSS was shown to have comparable psychometric features to the ESS and provided perceived sleepiness levels across the day in an efficient and cost-effective manner. It also enabled characterization of treatment response among a cohort of patients with obstructive sleep apnea.

Derivation of research diagnostic criteria for insomnia: report of an American Academy of Sleep Medicine Work Group.

Insomnia is a highly prevalent, often debilitating, and economically burdensome form of sleep disturbance caused by various situational, medical, emotional, environmental and behavioral factors. Although several consensually-derived nosologies have described numerous insomnia phenotypes, research concerning these phenotypes has been greatly hampered by a lack of widely accepted operational research diagnostic criteria (RDC) for their definition. The lack of RDC has, in turn, led to inconsistent research findings for most phenotypes largely due to the variable definitions used for their ascertainment. Given this problem, the American Academy of Sleep Medicine (AASM) commissioned a Work Group (WG) to review the literature and identify those insomnia phenotypes that appear most valid and tenable. In addition, this WG was asked to derive standardized RDC for these phenotypes and recommend assessment procedures for their ascertainment. This report outlines the WG's findings, the insomnia RDC derived, and research assessment procedures the WG recommends for identifying study participants who meet these RDC.

Comparative efficacy of zolpidem and temazepam in transient insomnia.

This study compared hypnotic effects of zolpidem 10 mg, temazepam 15 mg and 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 study, with data collected in 13 sleep laboratories. Subjects with normal sleep histories and without prior sleep laboratory experience were randomly assigned to treatment groups. Medications were administered 15 min before lights out, with polysomnographic monitoring for 7.5 h. Subjective questionnaires 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 measures ANOVAs. Neither agent significantly reduced objective sleep latency relative to placebo. Zolpidem reduced awakenings and wake after sleep onset (WASO); temazepam did not. Both agents improved sleep efficiency and most subjective sleep measures relative to placebo, with zolpidem superior for five of six subjective outcome measures compared to temazepam. SCT, morning sleepiness and morning concentration were not altered by any treatment. Zolpidem significantly reduced morning DSST performance; temazepam did not. Zolpidem 10 mg provided greater subjective hypnotic efficacy than temazepam 15 mg in this model of transient insomnia, with reduced polysomnographic awakenings and WASO. Impairment of DSST was seen with zolpidem but not temazepam. Copyright 2001 John Wiley & Sons, Ltd.