Sleep Perception Among Individuals With Posttraumatic Stress Disorder

897 Commentary—Pillai and Delahanty Nearly 70% of individuals with posttraumatic stress disorder (PTSD) report clinically significant levels of sleep disturbances,1 and sleep complaints appear more refractory to therapy than other features of the disorder.2 However, data from several polysomnography (PSG) and actigraphy-based studies suggest that individuals with PTSD often report sleep disturbances in the absence of any demonstrable disruption in objectively measured sleep, calling into question the validity of subjective sleep complaints in PTSD.3 Since healthy adults are capable of relatively accurately estimating sleep state and duration,4 some researchers suggest that individuals with PTSD exhibit a perceptual bias with regard to sleep.3 In this issue of SLEEP, Kobayashi and colleagues5 challenge these conceptualizations of sleep misperception and offer empirical evidence in favor of a more nuanced perspective. Consistently observed discrepancies between subjective and objective indices of sleep impairment among insomnia patients led some researchers to suggest a new phenotype of the disorder called “paradoxical insomnia”: a condition marked by significant sleep misperception.6 Evidence for sleep misperception in PTSD, however, remains less conclusive. Lack of replication as well as methodological inconsistencies in assessment techniques (PSG vs. actigraphy; daily sleep diary vs. retrospective questionnaire) and settings (home vs. laboratory) have prevented data comparisons across studies.3 Kobayashi et al.5 attempt to overcome these limitations by comparing self-reported sleep data from questionnaires and morning sleep diaries with more objective data from in-lab PSG and home actigraphy. Further, they assess whether discrepancies between subjective and objective sleep indices are moderated by current or prior PTSD status. According to results, trauma/PTSD did not consistently contribute to discrepancies between subjective and objective sleep measures. Specifically, participants who did not meet current PTSD criteria overestimated total sleep time (TST) relative to actigraphy measures. With respect to sleep onset latency (SOL), all participants overestimated SOL in the sleep diaries relative to PSG, but not to actigraphy. In addition, while participants with current or lifetime PTSD overestimated SOL via self-report questionnaires relative to PSG, the other groups underestimated SOL. Finally, all participants underestimated time spent awake after sleep onset (WASO) relative to actigraphy. COMMENTARY