(1331) Long-Term Durability of Hypoglossal Nerve Stimulation for Obstructive Sleep Apnea Following Pulse Generator Replacement

Introduction: Hypoglossal nerve stimulation (HGNS) is an established therapy for CPAP-intolerant obstructive sleep apnea (OSA), with the STAR trial and subsequent studies demonstrating sustained efficacy. Long-term outcomes following implantable pulse generator replacement, however, remain limited.

Methods: Patients from the original STAR trial cohort who subsequently underwent implantable pulse generator replacement were identified. Baseline pre-implant polysomnographic and clinical data were compared with post-exchange outcomes. Primary endpoints included apnea–hypopnea index (AHI), oxygen desaturation index (ODI), and Epworth Sleepiness Scale (ESS). Secondary measures included body mass index (BMI). Paired comparisons were performed using Wilcoxon signed-rank testing. Treatment response was assessed using Sher criteria (≥50% AHI reduction and post-treatment AHI < 20).

Results: Twelve patients underwent generator replacement at a mean of 8.8 years after initial implantation. Paired pre-implant and post–battery exchange polysomnographic data were available for 11 patients for AHI and ESS and for all 12 patients for ODI and BMI.. Mean AHI decreased from 42.0 ± 10.1 to 13.6 ± 16.6 events/hour (p = 0.0029, n = 11). Mean ODI improved from 37.8 ± 9.8 to 11.5 ± 13.8 events/hour (p = 0.0015, n = 12). ESS improved from 11.4 ± 3.7 to 7.5 ± 3.2 (p = 0.0049, n = 11). BMI remained stable (28.9 ± 2.5 vs 29.3 ± 3.7 kg/m², p = 0.57). Using Sher criteria, 72.7% (8/11) met responder status at post-exchange follow-up.

Conclusions: In this early hypoglossal nerve stimulation cohort with nearly a decade of follow-up, significant improvements in AHI, ODI, and daytime sleepiness relative to baseline were maintained after implantable pulse generator replacement, while body weight remained stable. More than 70% of patients continued to meet established responder criteria following generator exchange. These findings support the long-term durability of hypoglossal nerve stimulation therapy across device life cycles and provide reassurance that clinical benefit is preserved after battery replacement.