What Can Reduce Severity of Obstructive Sleep Apnea?

Cognitive behavioral therapy for insomnia (CBTi) was found to reduce severity of obstructive sleep apnea (OSA) by 15% in patients with comorbid insomnia and OSA, according to study findings published in European Respiratory Journal Open Research.

In a prior study, an estimated 39% to 55% of patients already diagnosed with OSA or sleep disordered breathing were indicated to have reported symptoms of insomnia. As researchers of the present study note, the link between OSA and insomnia may be casually related through sleep fragmentation and/or hyperarousal mechanisms.

While the efficacy of OSA treatment has been shown to improve insomnia severity, study authors highlight that the inverse relationship of insomnia treatment in OSA has yet to be investigated. Researchers sought to examine the potential of CBTi, a therapy designed to assist patients in changing actions or thoughts known to impair the ability to sleep well, in treating OSA severity.

The randomized controlled trial investigated CBTi on OSA severity, including 145 patients with comorbid insomnia and untreated OSA, controlling for potential sleep-stage and posture effects. Participants were randomized to a 4-session CBTi program (intervention) or no treatment (control), with apnoea—hypopnoea index (AHI), arousal index, and sleep architecture measurements being conducted via overnight sleep studies both pre and post-treatment. Data was then used to investigate the effect of CBTi, time, sleep stage (N1—3 or REM), and posture (supine or nonsupine) on OSA severity.

Compared with the control group, participants in the intervention group showed a 7.5 event greater AHI difference across sleep stages and postures, in which those administered CBTi showed a mean decrease of 5.5 events (95% CI, 1.3—9.7 events·h⁻¹ , Cohen’s d = 0.2, from 36.4 events·h⁻¹ pre-treatment) and those in the control group exhibited a mean increase of 2 events (95% CI, −2.0—6.1; events·h⁻¹ , d = 0.01, from 37.5 events·h⁻¹ at pretreatment; interaction P = .012).

Moreover, those in the CBTi group also showed a greater reduction in total number (mean difference = 5.6; 0.6—10.6; greater overall reduction; P = .029) and duration of nocturnal awakenings (mean difference = 21.1; 2.0—40.3 min greater reduction; P = .031) compared with the control group. There was no observed differences in the arousal index or sleep architecture.

“CBTi consolidates sleep periods and promotes a 15% decrease in OSA severity in patients with comorbid insomnia and OSA,” concluded the study authors. “This suggests that insomnia disorder may exacerbate OSA and provides further support for treating insomnia in the presence of comorbid OSA.”

Reference

Sweetman A, Lack L, McEvoy RD, et al. Cognitive behavioural therapy for insomnia reduces sleep apnoea severity: a randomised controlled trial [published online May 17, 2020]. ERJ Open Res. doi: 10.1183/23120541.00161-2020.