Effectiveness of non-surgical weight loss interventions on obstructive sleep apnoea severity and cardiometabolic outcomes: A systematic review and meta-analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of randomized controlled trials
PubMed 41762860 · doi:10.1016/j.sleep.2026.108878
What was done
This systematic review and meta-analysis of randomized controlled trials (PROSPERO: CRD420250641507) evaluated the effects of non-surgical weight loss interventions on obstructive sleep apnoea (OSA) severity and cardiometabolic outcomes in adults. Searches were conducted in PubMed, EMBASE, Cochrane Library, and Web of Science following PRISMA guidelines. The primary outcome was the Apnea-Hypopnea Index (AHI); secondary outcomes included blood pressure and anthropometric measures. Data were synthesized using random-effects models, with subgroup analyses by follow-up duration and type 2 diabetes status. Risk of bias and GRADE certainty were formally assessed.
What was found
Eighteen RCTs involving 2,242 participants were included. Non-surgical weight loss interventions significantly improved the primary and all secondary outcomes (all p < 0.01): - Apnea-Hypopnea Index (AHI): MD = -11.10 (p < 0.0001) - Body weight: MD = -6.53 - Body mass index (BMI): MD = -2.40 - Waist circumference: MD = -5.13 - Neck circumference: MD = -0.97 - Systolic blood pressure: MD = -6.51 - Diastolic blood pressure: MD = -3.26 Benefits were most robust in the short to mid-term. Heterogeneity was high (I² > 90%) for most outcomes, and the overall certainty of evidence was rated as very low.
Why it matters
Non-surgical weight loss provides meaningful short-to-mid-term reductions in OSA severity and improves key cardiometabolic markers. However, the very low GRADE certainty indicates substantial uncertainty around effect sizes and highlights the need for trials evaluating long-term maintenance.
Limits
The overall certainty of evidence was rated very low by GRADE criteria, driven primarily by very high statistical heterogeneity (I² > 90%) across most outcomes. The abstract does not specify the exact intervention modalities pooled (e.g., diet, lifestyle, pharmacotherapy) nor does it report confidence intervals for the effect estimates. Long-term durability beyond the mid-term remains unconfirmed.
Cited by
- supports The most effective intervention to resolve sleep apnea is weight loss.