The Clinical Effects of the Phlegm-Resolving Method in the Treatment of Obstructive Sleep Apnea-Hypopnea Syndrome: A Meta-Analysis of Randomized Controlled Trials

Objective. This study evaluated the clinical efficacy and safety of the phlegm-resolving method in traditional Chinese medicine (TCM) for the treatment of obstructive sleep apnea-hypopnea syndrome (OSAHS). Methods. We searched the PubMed, Embase, Cochrane Library, Wanfang, CNKI, and VIP databases according to specific search strategies. The data were analyzed using RevMan 5.3 software. Results. Thirteen randomized controlled trials (RCTs) comprising 882 patients with OSAHS were selected. Compared to continuous positive airway pressure (CPAP), the phlegm-resolving method of TCM combined with CPAP significantly more effectively improved the apnea/hypopnea index (AHI), Epworth Sleepiness Scale (ESS), and lowest oxygen saturation (LSaO(2)). While the treatment effect was better for a treatment duration of >6 weeks compared to that at <= 6 weeks, the difference was not statistically significant. Compared to health guidance alone, the combination of the phlegm-resolving method in TCM with health guidance showed significantly better efficacy in improving AHI, ESS, and LSaO(2). In terms of reducing ESS and increasing LSaO(2), the effect was better for treatment courses >6 weeks. When the AHI was reduced, a duration of <= 6 weeks showed more advantages; however, the difference was not significant. Only one study reported mild nausea in one participant in the treatment group at the initial stage of treatment; the remaining studies did not mention any side effects. Conclusion. Both the resolving phlegm method of TCM combined with CPAP and the resolving phlegm method of TCM combined with health guidance were more effective in improving AHI, LSaO(2), and ESS compared to the control group.