Hypoglossal nerve stimulation long-term clinical outcomes: a systematic review and meta-analysis

Objective To perform a systematic review and meta-analysis for studies evaluating hypoglossal nerve stimulation (HNS) clinical outcomes in the treatment of moderate to severe obstructive sleep apnea (OSA). Methods Two authors conducted a literature search to identify prospective studies in PubMed/MEDLINE, Google Scholar, and Cochrane Library databases. The last search was performed on November 17, 2018. Results A total of 350 patients (median age 54.3 (IQR 53-56.25) years, BMI 29.8 (IQR 28.8-31.6) kg/m(2)) from 12 studies were included. The procedure has obtained a surgical success rate of 72.4% (Inspire), 76.9% (ImThera), 55% (Apnex) at 12 months, and 75% (Inspire) at 60-month follow-up. At 12 months, the apnea-hypopnea index (AHI) mean differences was - 17.50 (Inspire; 95% CI: - 20.01 to - 14.98,P < 0.001), - 24.20 (ImThera; 95% CI: - 37.39 to 11.01,P < 0.001), and - 20.10 (Apnex; 95% CI: - 29.62 to - 10.58,P < 0.001). The AHI mean reduction after 5 years was - 18.00 (Inspire, - 22.38 to - 13.62,P < 0.001). The Epworth sleepiness scale (ESS) mean reduction was - 5.27 (Inspire), - 2.90 (ImThera), and - 4.20 (Apnex) at 12 months and - 4.40 (Inspire) at 60 months, respectively. Only 6% of patients reported serious device-related adverse events after 1- and 5-year follow-up. Conclusion HNS has obtained a high surgical success rate with reasonable long-term complication rate related to the device implanted. The procedure represents an effective and safe surgical treatment for moderate-severe OSA in selected adult patients who had difficulty accepting or adhering to CPAP treatment.