Insomnia as a Clinical Predictor of Hypoglossal Nerve Stimulation Settings and Treatment Success.

OBJECTIVES: To examine the impact of comorbid insomnia and obstructive sleep apnea (COMISA) on hypoglossal nerve stimulation (HNS) stimulation levels and rates of therapeutic success. METHODS: A retrospective chart review included adult OSA patients who received HNS surgery. Demographic information, baseline Insomnia Severity Index (ISI), pre and post implant sleep studies, and HNS stimulation data were collected. HNS therapy success was evaluated as ≥ 50% AHI reduction and AHI ≤ 15 (Sher15 criteria) and based on HNS treatment pathways using AHI symptoms and adherence. RESULTS: The cohort included 80 OSA patients treated with HNS therapy including 35.5% (n = 30) with pre-surgery COMISA based on ISI score ≥ 15. COMISA patients had lower therapeutic HNS stimulation levels (1.5 V (COMISA) vs. 1.9 V, p < 0.01) and lower mean HNS stimulation level change from baseline (0.8 V (COMISA) vs. 1.01 V, p < 0.05) compared to non-COMISA patients. Fewer COMISA patients met Sher15 criteria (33.3% (n = 10) (COMISA) vs. 62.0% (n = 31), p = 0.02). When classifying COMISA and non-COMISA patients by post-operative HNS pathways, 60.0% (n = 18) of COMISA patients were within the Yellow Pathway Type 2 (adequate adherence, Sher15 nonresponse) compared to 32.0% (n = 16) of non-COMISA (p = 0.02), with no significant differences in rates within the other pathways. CONCLUSION: COMISA patients have lower therapeutic HNS stimulation levels, fewer stimulation level changes, and reduced rates of achieving Sher15 success criteria compared to those without COMISA. Managing expectations during stimulation uptitration and balancing implant stimulation tolerance and effectivness are required to optimize HNS outcomes.