Clinical Predictors of OSA Treatment Success Following Implantation of a Hypoglossal Nerve Stimulation Device

Objective To identify prognostic indicators associated with successful hypoglossal nerve stimulation (HGNS) therapy to treat obstructive sleep apnea (OSA), focusing on patients’ physiologic response to awake tongue protrusion. Study Design Retrospective chart review. Setting Tertiary care center. Methods We included consecutive patients with moderate‐severe OSA who underwent HGNS implantation from December 2017 to December 2019. Data abstracted include standard demographics, body mass index (BMI), pre‐ and postoperative apnea‐hypopnea index (AHI), and Friedman tongue position (FTP). Additionally, change in hypopharyngeal cross‐sectional area on awake tongue protrusion was abstracted. Patients protruded their tongues, and the physician visualized change. Positive change in hypopharyngeal cross‐sectional area was documented as +1 and a negative change as −1. Chi‐square tests for independence and logistic regression analysis were performed to determine indicators of successful surgery. Results Thirty‐nine patients were included in this study. Mean ± SD AHI decreased significantly from 43.1 ± 17.36 to 9.18 ± 8.18. Surgical success was achieved in 79.5% of patients. Variables analyzed included BMI >32, preoperative AHI, FTP, and change in hypopharyngeal cross‐sectional area on awake tongue protrusion (positive, 65.8%; negative, 34.2%). Positive predictors of success were positive change in hypopharyngeal cross‐sectional area ( P =. 0133), severe OSA ( P =. 0290), and FTP IIb ( P <. 0001). Negative predictors were BMI >32 ( P =. 041) and negative change in hypopharyngeal cross‐sectional area ( P =. 02). Conclusion Positive change in hypopharyngeal cross‐sectional area on awake tongue protrusion and severe baseline AHI were positive predictors of successful HGNS therapy. Negative change in hypopharyngeal cross‐sectional area on awake tongue protrusion and BMI >32 were negative predictors.