Body Mass Index and Hypoglossal Nerve Stimulation Outcomes: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis evaluated how body mass index (BMI) influences surgical outcomes of hypoglossal nerve stimulation (HGNS) for obstructive sleep apnea (OSA), specifically comparing patients with BMI ≥ 32 kg/m² to those with BMI < 32 kg/m².

PubMed, Embase, and Scopus were searched from January 2014 to April 2025 for prospective and retrospective cohort studies or case-control studies reporting HGNS outcomes stratified by BMI.

Following PRISMA guidelines, data were extracted on study design, demographics, baseline apnea-hypopnea index (AHI), and postoperative outcomes. Surgical success was defined using Sher or modified Sher criteria. Random-effects meta-analysis was performed using the DerSimonian and Laird method. Fixed-effect inverse-variance weights were first calculated, and between-study heterogeneity was quantified using Cochran's Q statistic and expressed as the I ² statistic. Study quality was assessed with the Newcastle-Ottawa Scale.

Seven studies (n = 1572) were included in the qualitative synthesis; four were included in the meta-analysis. Qualitative findings were mixed, with some studies reporting poorer outcomes at higher BMI and others showing no difference. The pooled odds ratio for treatment success in the BMI ≥ 32 kg/m² group versus < 32 kg/m² was 0.87 (95% CI: 0.68-1.11). Between-study heterogeneity was low (Q = 4.11, df = 3, p = 0.25; I ² = 27%), indicating relatively consistent effect estimates across studies.

Elevated BMI was associated with a nonsignificant trend toward lower HGNS surgical success, but outcomes were broadly consistent across studies. Many patients with BMI ≥ 32 kg/m² achieved meaningful objective and subjective improvements, challenging rigid BMI-based eligibility criteria and supporting individualized candidacy assessment.