For a study, it was determined that despite rigorous patient selection based on baseline features and drug-induced sleep endoscopy, approximately one-third of patients with obstructive sleep apnea (OSA) were treated with hypoglossal nerve stimulation (HGNS) therapy were incomplete responders. The pathophysiological factors driving favorable versus inadequate responses to HGNS therapy were assessed using polysomnographic endotyping in a study. Researchers included the STAR (Stimulation Therapy for Apnea Reduction) trial’s baseline polysomnography data. Raw baseline polysomnographic data from 91/126 individuals were available for analysis. According to Sands and colleagues, loop gain, arousal threshold, collapsibility, and muscle compensation were computed from baseline polysomnography data (AJRCCM 2018, SLEEP 2018). They investigated logistic regressions, a technique for predicting the outcome of AHI-adjusted relationships between HGNS response (>50% reduction in AHI to 10/h at 1 year) and OSA characteristics.
Overall, HGNS treatment decreased AHI from 30.7 (24.9–39.9) events/h to 8.5 (4.0–19.5) events/h (P<0.0001; median [quartiles 1–3]); N = 53/91 were responders. A favorable response to therapy was associated with a higher arousal threshold (odds ratio 95% CI: 6.76 [2.44–23.3], P=0.001), greater compensation (odds ratio: 4.22 [1.70–12.55] per SD, P=0.004), and lower loop gain (in milder collapsibility, per significant interaction, P=0.003) in adjusted analysis. Before the adjusted analysis, responders had a greater arousal threshold. Expected responders had a treatment AHI that was about four times lower than predicted non-responders (4.9 [2.7–8.5] vs 20.7 [10.9–29.7], P<0.0001; median [quartiles 1–3]); the differences remained significant the following cross-validation. The pathophysiological features that cause OSA, specifically a greater arousal threshold, are linked to favorable responses to HGNS therapy. Individuals can prioritize favorable features that could potentially be for precision HGNS therapy and meet established criteria.