Abstract

Introduction

Obstructive sleep apnoea (OSA) is independently associated with cardiovascular disease processes. The benefit of continuous positive airway pressure (CPAP) therapy, however, is uncertain. Here, we aim to evaluate the effect of CPAP vs. a glucagon-like peptide (GLP)-1 (Liraglutide)-mediated weight loss strategy (LWR) on vascular inflammation using fluorodeoxyglucose (FDG) PET-CT.

Methods

These are data from an ongoing randomised proof-of-concept study (clinicaltrials.gov: NCT04186494). 30 patients with moderate to severe OSA without diabetes were randomised to CPAP, LWR alone or both in combination for 24 weeks. All patients underwent FDG-PET CT at baseline and at study completion on the same PET-CT system (Siemens Biograph mCT). Quantitative analysis of vascular inflammation was performed by measuring aorta target-to-background ratio (TBR) by two blinded investigators in consensus.

Results

So far, 26 subjects (51±7 years, 80% males, apnoea-hypopnoea index (AHI) 38±17/hr, body mass index (BMI) 34.8 ±3 kg/m2) have completed the study. There was a significant decrease in BMI with LWR vs CPAP (-1.6±1.1 vs 0.5±2.1, p=0.038), while the reduction in AHI was greater with CPAP vs LWR (-31±7 vs. -10±6, p = 0.096). However, only subjects on CPAP had a significant decrease in vascular inflammation versus baseline and compared to LWR, CPAP appears to be more beneficial in reducing PET-CT uptake of the aorta (intention-to-treat analysis p=0.088, per protocol p=0.062).

Conclusions

CPAP therapy but not GLP-1-mediated weight loss improves vascular inflammation in OSA, novel findings supporting benefit of CPAP on cardiovascular disease processes.