Subjective–objective sleep discrepancy in patients with insomnia during and after cognitive behavioural therapy: An actigraphy study

Abstract

Although patients with insomnia often show a discrepancy between self-reported and objective sleep parameters, the role of and change in this phenomenon during treatment remain unclear. The present study aimed to assess the effect of cognitive behavioural therapy for insomnia on subjective and objective sleep discrepancy of total sleep time, sleep-onset latency and wake after sleep onset. The total sleep time discrepancy was also assessed across the entire therapy. The second aim was to examine the treatment outcome of two insomnia groups differing in sleep perception. Thirty-six adults with insomnia (mean age = 46.7 years, SD = 13.9; 22 females) were enrolled in the final analyses. Patients underwent a 6-week group cognitive behavioural therapy for insomnia programme. Sleep diary and actigraphy measurements were obtained during the therapy. Patients who underestimated total sleep time (n = 16; underestimating group) were compared with patients who accurately perceived or overestimated total sleep time (n = 20; accurate/overestimating group). After cognitive behavioural therapy for insomnia, a significant decrease of total sleep time and sleep-onset latency discrepancy was observed without a change in wake after sleep onset discrepancy in the total sample. Only the underestimating group reported decreased sleep-onset latency discrepancy after the treatment, whereas total sleep time discrepancy significantly changed in both groups. The underestimating group showed a significant decrease of total sleep time discrepancy from Week 1 to Week 2 when the sleep restriction was implemented, whereas the accurate/ overestimating group showed the first significant change at Week 4. In conclusion, both groups differing in sleep perception responded similarly to cognitive behavioural therapy for insomnia, although different In conclusion, both groups differing in sleep perception responded similarly to cognitive behavioural therapy for insomnia, although different therapeutic components could play important roles in each group. components could play important roles in each group.

The Effect of Cognitive Behavioural Therapy for Insomnia (CBT-I) on Subjective–Objective Sleep Discrepancy in Individuals with Co-Morbid Insomnia and Sleep Apnoea: A Randomised Controlled Trial

“…These findings indicate the importance of a waitlist control group and could indicate regression to the mean, first night effects, or perhaps a learning effect where studies that draw participant attention to sleep variables may influence subjective responses over time, irrespective of treatment interventions. These results contrast with previous studies in insomnia samples that found evidence for a reduction of SOSD after CBT-I [14,23,25,47,48].…”

“…Previous studies have reported that CBT-I reduces the discrepancy between subjective and objective measures of sleep in individuals with insomnia alone [14,23,25,46]. This is likely driven by a large improvement in subjective sleep estimates, and minimal change in objective sleep during treatment that results in a convergence of the two measures post CBT-I-treatment but could also be explained by regression to the mean [23,24].…”

“…This is likely driven by a large improvement in subjective sleep estimates, and minimal change in objective sleep during treatment that results in a convergence of the two measures post CBT-I-treatment but could also be explained by regression to the mean [23,24]. Crönlein et al [14] and Jank ů et al [25] did not have control groups, and Kay et al [46] had a control group whereby the participants did not have insomnia ("good sleepers"), meaning that these studies were not RCTs with a sensible comparator group. Whereas the current study was a RCT and therefore it importantly controlled for temporal effects independent of CBT-I.…”

“…Furthermore, CBT-I in patients with insomnia alone leads to large improvements in subjective sleep estimates and improvements in assessments of daytime functioning and feelings, despite little change in objective total sleep time. This results in a convergence of the two measures post-treatment, and a reduction in SOSD, meaning that subjective and objective measures align more closely [14,[23][24][25]. However, few studies have investigated SOSD in patients with COMISA and no study has investigated the effect of CBT-I on SOSD in a COMISA sample.…”

Non‐pharmacologic treatment of insomnia in primary care settings

“…After 6‐week of the CBT‐i program, Janků and colleagues reported a significant reduction of total sleep time discrepancy. On the other hand, change in wake after sleep onset discrepancy was not observed 41 …”