Cognitive behavioral therapy for insomnia (CBT-i) in patients with fibromyalgia: a systematic review and meta-analysis

Purpose We aimed to evaluate the effectiveness of CBT-i in patients with fibromyalgia in comparison with other non-pharmacological treatments. Methods Randomized controlled trials assessing the effects of CBT-i in adults with fibromyalgia, published in English or Spanish, were eligible. Electronic searches were performed using PubMed, Scopus, The Cochrane Library, WebOfKnowledge and Psicodoc databases in March 2021. The main outcome measures were sleep efficiency and sleep quality. Secondary outcomes included pain, depression, and anxiety. Results Of 226 studies reviewed, five were included in the meta-analysis. CBT-i compared with non-pharmacological treatments showed no significant improvements in sleep efficiency (p = 0.05; standardized mean difference (SMD) [95% CI] 0.31 [-0.00 to 0.61]). CBT-i showed significant improvements in sleep quality (p = 0.009; SMD [95% CI] - 0.53 [-0.93 to -0.13]), pain (p = 0.002; SMD [95% CI] - 0.41 [-0.67 to -0.16]), anxiety (p = 0.001; SMD [95% CI] - 0.46 [-0.74 to 0.18]) and depression (p = 0.02; SMD [95% CI] - 0.33 [-0.61 to -0.05]), compared to non-pharmacological treatments. Effect sizes ranged from small to moderate. Conclusions CBT-i was associated with a significant improvement in sleep quality, pain, anxiety, and depression, although these results are retrieved from very few studies with only very low to low quality evidence.