Effectiveness of Cognitive Behavioral Therapy for Sleep Disorder: An overview of Systematic Review

Article information

J Korean Med. 2022;43(2):75-91
Publication date (electronic) : 2022 June 1
doi : https://doi.org/10.13048/jkm.22021
1Department of Preventive Medicine, College of Korean Medicine, Dongguk University, Gyeongju, Republic of Korea
2Department of Preventive Medicine, Dongguk University Graduate School of Korean Medicine, Seoul, Republic of Korea
3College of Korean Medicine, Dongguk University, Gyeongju, Republic of Korea
Correspondence to: Min Kyung Hyun, Department of Preventive Medicine, College of Korean Medicine, Dongguk University, 123, Dongdae-ro, Gyeongju-si, Gyeongsanbuk-do, 38066, Republic of Korea, Tel:+82-54-770-2655, Fax:+82-54-770-2281, E-mail:mk3three@dongguk.ac.kr

These authors contributed equally to this work.

Received 2022 January 21; Revised 2022 April 1; Accepted 2022 May 19.

Abstract

Objectives

The purpose of this overview was to summarize the evidence regarding the effectiveness of Cognitive Behavioral Therapy (CBT) for sleep disorders through systematic reviews (SRs) and meta-analyses (MAs).

Methods

An overview of systematic review was conducted according to the study protocol (reviewregistry1320). A comprehensive literature search was performed using three databases (Pubmed, Cochrane Central Register of Controlled Trials, and Web of Science) and three Korean databases (KoreaMed, KMbase, and ScienceON). Final studies were selected by three authors according to inclusion and exclusion criteria, and data needed for analysis were extracted by a pre-planned extraction framework. Methodological quality of systematic review was assessed using the ‘Assessment of multiple systematic reviews 2 (AMSTAR2)’.

Results

Fourteen SRs and MAs were included, of which eleven SRs were performed MAs. Twelve studies studied insomnia among sleep disorders, and the rest are nightmares and sleep disturbances with PTSD. Ten studies reported the effect of CBT on sleep disorders measured by insomnia severity index (ISI) and sleep onset latency (SOL), and all reported a significant improvement effect. Eight studies reported the effect of CBT on sleep disorders measured by wake time after sleep onset (WASO), and seven studies reported a significant improvement effect. The methodological quality of the studies evaluated with AMSTAR 2 was mainly low or very low because of omission of protocol registration and excluded study list.

Conclusions

Practical guidelines and studies show that CBT is effective for sleep disorders, but access to CBT needs to be improved.

Fig. 1

Study selection process

Fig. 2

Methodological and reporting quality: Evaluation results of each AMSTAR2 question of included studies

Characteristics of the included systematic review

Overall result of meta-analysis

Summary of the systematic reviews of the conclusion of the effects of CBT

Assessment of multiple systematic review 2(AMSTAR2) result of the 12 included systematic review

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Article information Continued

Fig. 1

Study selection process

Fig. 2

Methodological and reporting quality: Evaluation results of each AMSTAR2 question of included studies

Table 1

Characteristics of the included systematic review

First author (year) Country Number of included studies (Total sample size) Comorbid disease Age (mean or range) Gender Comparator Outcome measure
ISI PSQI SOL TST WASO NOA SE
Insomnia
 SR+MA
Cheng (2012) China 4 RCTs (443) 39.6–56.7 M : 201 (45.40%)
F : 242 (54.60%)
Waiting list
Alternative treatment
P P N N P P
Trauer (2015) Australia 20 RCTs (1,162) 55.6 M : 418 (36.00%)
F : 744 (64.00%)
Waiting list
Placebo
Hygiene
Usual treatment
P N P P
Zachariae (2016) Denmark 11 RCTs (1,460) NR NR Waiting list
Treatment as usual
Active control
P P P P P P
Seyffert (2016) United States 13 RCTs (2,392) 20–56 M : 696 (29.10%)
F : 1,696 (70.90%)
Waiting list P P P P P
Johnson (2016) Canada 8 RCTs (752) Cancer NR NR Waiting list
Treatment as usual
Sleep education
Placebo
Mindfulness based stress reduction
P P P P
Cheung (2019) Canada 12 RCTs (1625) 37.5–77.2 M : 553 (34.00%)
F :1,073 (66.00%)
Treatment as usual
Primary care mental health
General practice
Education control
Self-monitoring control
P P
Feng (2020) China 17 RCTs (1,756) Depression 32.21–57.8 M : 673 (38.30%)
F : 1,083 (61.70%)
Waiting list
No treatment
Pharmacological treatment
P P
Zhou (2020) China 13 RCTs (853) 30.8–59.8 M : 189 (22.10%)
F : 664 (77.90%)
Behavioral desensitization
Hygiene
P P P N P N P
Curtis (2021) UK 5 RCTs (470) Tinnitus 22–83 NR Waiting list
Weekly monitoring control group
Online discussion forum
P
Tsai (2022) Taiwan 4 RCTs (3,970) 15.3–24.8 M : 1,969(49.60%)
F : 2,001 (50.40%)
Waiting list
Sleep-hygiene
P P
 SR
Wang (2005) Taiwan 7 RCTs (396) 36.7–64.7 M : 150 (37.90%)
F : 246 (62.10%)
Placebo
Waiting list
Stimulus control
Relaxation training
Educational programme
Pharmacological treatment
P U P U
Mitchell (2012) United States 5 RCTs (223) 25–64 NR Pharmacological treatment P U P P
NightMare
 SR
Lancee (2008) Netherlands 12 RCTs (437) NR NR Waiting list N
Sleep disturbances treating symptom in PTSD
 SR+MA
Ho (2016) China 11 RCTs (593) 45.3 M : 382 (64.40%)
F : 211 (35.60%)
Waiting list
Treatment as usual
Hygiene
Placebo
P P P N P P

PSIQ, Pittsburgh Sleep Quality; ISI, Insomnia Severity Index; SOL, Sleep Onset Latency; TST, Total sleep time; WASO, Wake time after sleep onset; NOA, Number of awakenings; SE, Sleep efficiency; SR, Systematic review; MA, meta-analysis; RCTs, Randomized Controlled Trials; M, Male; F, Female; P, Positive; N, Negative; U, Uncertain; NR, Not reported;

Table 2

Overall result of meta-analysis

First author (year) Comparisons (Patients) Statistical Model Pooled effect 95% CI Heterogeneity I2
Insomnia

Sleep onset latency

 Chneg (2012) CBT-I versus Control group Fixed −0.55 −0.80, −0.30 0%
 Trauer (2015) CBT-I versus Control group Random −19.03 −23.93, −14.12 41.9%
 Seyffert (2016) CBT versus Waiting list group Random −10.68 −16.00, −5.37 4.3%
 Zachariae (2016) CBT versus Control group Random 0.41 0.29, 0.53 0%
 Zhou (2020) CBT versus Control group Random −0.36 −0.62, −0.10 51%

Number of awakenings

 Chneg (2012) CBT-I versus Control group Fixed −0.45 −0.70, −0.20 51%
 Zachariae (2016) CBT versus Control group Random 0.21 0.05, 0.37 2.5%
 Zhou (2020) CBT versus Control group Random 0.20 −0.16, 0.57 0%

Wake time after sleep onset

 Chneg (2012) CBT-I versus Control group Fixed −0.18 −0.43, 0.06 55%
 Trauer (2015) CBT-I versus Control group Random −26.00 −36.52, −15.48 7.2%
 Seyffert (2016) CBT versus Waiting list group Random −20.44 −34.87, −6.01 69.3%
 Zachariae (2016) CBT versus Control group Random 0.45 0.25, 0.66 48.5%
 Zhou (2020) CBT versus Control group Random −0.21 −0.38, −0.04 34%

Total sleep time

 Chneg (2012) CBT-I versus Control group Fixed 0.22 −0.03, 0.46 0%
 Trauer (2015) CBT-I versus Control group Random 7.61 −0.51, 15.74 3.1%
 Seyffert (2016) CBT versus Waiting list group Random 19.57 8.56, 30.58 24.7%
 Zachariae (2016) CBT versus Control group Random 0.29 0.17, 0.42 5.4%
 Zhou (2020) CBT versus Control group Random −0.13 −0.30, 0.04 45%

Sleep efficiency

 Chneg (2012) CBT-I versus Control group Fixed 0.40 0.15, 0.64 63%
 Trauer (2015) CBT-I versus Control group Random 9.91 8.09, 11.73 47.1%
 Johnson (2016) CBT versus Control group Random 0.53 0.38, 0.68 0%
 Seyffert (2016) CBT versus Waiting list group Random 7.22 5.13. 9.32 39.5%
 Zachariae (2016) CBT versus Control group Random 0.58 0.36, 0.81 68.4%
 Cheung (2019) CBT versus Control group Fixed 0.38 0.25, 0.51 60%
 Zhou (2020) CBT versus Control group Random 0.18 0.00, 0.36 36%

Insomnia Severity Index

 Chneg (2012) CBT-I versus Control group Fixed −0.86 −1.18. −0.53 0%
 Seyffert (2016) CBT versus Waiting list group Random −4.29 −7.12, −1.46 86.7%
 Zachariae (2016) CBT versus Control group Random 1.09 0.74, 1.45 82.8%
 Cheung (2019) CBT versus Control group Fixed 0.40 0.24, 0.55 81%
 Feng (2020) CBT versus no treatment group Random −4.47 −7.46, −1.48 86%
 Zhou (2020) CBT versus Control group Random −0.74 −0.92, −0.56 39%
 Curtis (2021) CBT versus Control group Random −3.28 −4.51. −2.05 0%

Pittsburgh sleep quality index

 Feng (2020) CBT versus no treatment group Random −2.57 −3.50, −1.65 64%
 Zhou (2020) CBT versus Control group Random −0.76 −1.09, −0.42 61%

Insomnia Severity Index and Pittsburgh sleep quality index

Tsai (2022) CBT versus Control group Random −0.58 −1.03, −0.13 84%

Sleep disturbances

 Sleep onset latency

 Ho (2016) CBT versus Waiting list or psychoeducation group Random −0.83 −1.19, −0.47 0%

Wake time after sleep onset

 Ho (2016) CBT versus Waiting list or psychoeducation group Random −1.02 −1.39. −0.66 0%

Total sleep time

 Ho (2016) CBT versus waiting list or psychoeducation group Random 0.39 −0.05, 0.84 38%

Sleep efficiency

 Ho (2016) CBT versus waiting list or psychoeducation group Random 1.15 0.75, 1.56 37%

Insomnia Severity Index

 Ho (2016) CBT versus waiting list or psychoeducation group Random −1.15 −1.81, −0.49 77%

Pittsburgh sleep quality index
 Ho (2016) CBT versus waiting list or psychoeducation group Random −0.87 −1.18, −0.56 33%

Table 3

Summary of the systematic reviews of the conclusion of the effects of CBT

First author (year) Authors’ main conclusions
Insomnia
Cheng (2012) CCBT is effective as a short-term self-treatment therapy for insomnia. CCBT-I may be an acceptable low-intensity treatment model for insomnia.
Trauer (2015) As recommended by the guidelines for use as the first-line treatment for insomnia, CBT-I is a highly effective treatment for non-comorbid chronic insomnia.
Zachariae (2016) Internet-delivered CBT-I showed a statistically significant and strong effect on improving the ISI. A study is needed to directly compare internet-delivered CBT-I, face to face CBT-I, and pharmacotherapy.
Seyffert (2016) Internet-delivered CBT-I is effective in improving sleep in adults with insomnia. Efforts should be made to increase the acceptability and applicability of Internet-delivered CBT-I.
Johnson (2016) CBT-I is effective in improving sleep outcomes in cancer survivors. Future studies should investigate the cost-effective delivery method and improvement in quality of life of CBT-I.
Cheung (2019) While it demonstrates the validity and usefulness of providing a lower-tiered CBT-I program as the first-line treatment in a community settings, more standardized research is needed to reach a firm conclusion.
Feng (2020) Although CBT-I seems to be effective and safe for insomnia comorbid with depression, it is unclear whether
CBT-I can improve the depression.
Zhou (2020) CBT-I is effective for patients with insomnia comorbid with medical or psychiatric, but the effect size of the treatment decreases with time.
Wang (2005) CBT showed statistically significant improvement in patients with persistent primary insomnia. So, most nurses should be able to deliver CBT to primary insomnia patients.
Mitchell (2012) CBT-I is an effective insomnia treatment with durable results in short visits.
Curtis (2021) CBT-based interventions can significantly improve sleep in adults with tinnitus
Tsai (2022) These preliminary findings from the meta-analysis suggest that dCBT-i is a moderately effective treatment in managing insomnia in younger age groups.
Nightmare
Lancee (2008) Nightmare-focused CBT consisting of exposure and imagery rehearsal therapy is effective for nightmares, but further research is needed to determine which of exposure and imagery rehearsal therapy is superior.
Sleep disturbances treating symptom in PTSD
Ho (2016) CBT is effective in treating PTSD symptoms as well as sleep disturbances, but further studies are needed due to the lack of related studies.

CBT-I, Cognitive behavioral therapy for insomnia; CCBT-I, Computerized cognitive behavioral therapy for insomnia;

Table 4

Assessment of multiple systematic review 2(AMSTAR2) result of the 12 included systematic review

Author (year) AMSTAR 2 Overall methodological quality

Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 Q11 Q12 Q13 Q14 Q15 Q16
Wang (2005) Y N Y PY Y Y N Y PY N No-MA No-MA N N No-MA N Critically low
Lancee (2008) Y N Y Y Y Y N Y N N No-MA No-MA N N No-MA Y Critically low
Mitchell (2012) Y N Y Y N N N Y N N No-MA No-MA Y N No-MA Y Critically low
Cheng (2012) Y N N Y N N N Y N Y Y N N N N Y Critically low
Trauer (2015) Y PY Y Y Y Y N PY Y Y Y Y Y Y Y Y Low
Ho (2016) Y N Y Y Y Y Y Y Y N Y Y Y N Y Y Low
Zachariae (2016) Y Y Y Y Y Y N Y Y N Y Y Y Y Y Y Low
Seyffert (2016) Y Y Y Y Y Y N PY Y N Y Y Y Y Y Y Low
Johnson (2016) Y N Y Y Y Y N Y Y N Y Y Y Y Y Y Critically low
Cheung (2019) Y PY Y Y Y Y N Y Y N Y Y Y Y Y Y Low
Feng (2020) Y PY Y Y Y Y N Y Y N Y Y Y Y Y Y Low
Zhou (2020) Y Y Y Y Y Y N Y Y N Y Y Y Y Y Y Low
Curtis (2021) Y Y Y Y Y Y N Y Y Y Y Y Y Y Y Y Low
Tsai (2022) Y Y Y Y Y Y N Y Y Y Y Y Y Y Y Y Low

Q1 : Did the research questions and inclusion criteria for the review include the components of PICO?

Q2 : Did the report of the review contain an explicit statement that the review methods were established prior to the conduct of the review and did the report justify any significant deviations from the protocol?

Q3 : Did the review authors explain their selection of the study designs for inclusion in the review?

Q4 : Did the review authors use a comprehensive literature search strategy?

Q5 : Did the review authors perform study selection in duplicate?

Q6 : Did the review authors perform data extraction in duplicate?

Q7 : Did the review authors provide a list of excluded studies and justify the exclusions?

Q8 : Did the review authors describe the included studies in adequate detail?

Q9 : Did the review authors use a satisfactory technique for assessing the risk of bias (RoB) in individual studies that were included in the review?

Q10 : Did the review authors report on the sources of funding for the studies included in the review?

Q11 : If meta-analysis was performed did the review authors use appropriate methods for statistical combination of results?

Q12 : If meta-analysis was performed, did the review authors assess the potential impact of RoB in individual studies on the results of the meta-analysis or other evidence synthesis?

Q13 : Did the review authors account for RoB in individual studies when interpreting/discussing the results of the review?

Q14 : Did the review authors provide a satisfactory explanation for, and discussion of, any heterogeneity observed in the results of the review?

Q15 : If they performed quantitative synthesis did the review authors carry out an adequate investigation of publication bias (small study bias) and discuss its likely impact on the results of the review?

Q16 : Did the review authors report any potential sources of conflict of interest, including any funding they received for conducting the review?

Y : Yes

PY : Partial Yes

No-MA : No meta-anlysis conducted