Introduction: The benefit of continuous positive airway pressure (CPAP) therapy on cardiovascular (CV) diseases in obstructive sleep apnoea (OSA) remains uncertain. Novel imaging methods allow quantification of non-calcified coronary artery plaque subtypes including low-density plaque, which is prognostic of future CV events. Here, we aim to evaluate the potential effect of CPAP vs. glucagon-like peptide (GLP)-1 (Liraglutide)-mediated weight loss (LWR) on coronary artery plaque volumes.

Methods: These are data from a randomized proof-of-concept study (clinicaltrials.gov:NCT04186494). 30 patients with moderate to severe OSA were randomised to CPAP, LWR alone or both in combination for 24 weeks. All patients underwent CT Coronary Angiogram at baseline and those with visible coronary artery disease on initial scan underwent repeat scan at study completion(n=17, 5-6 per group). Coronary artery quantitative plaque volume analysis was performed using automated AI-enabled cardiac CT software (Circle cvi42, v5.16).

Results: 30 subjects (50±7 years, 80% males, apnoea-hypopnoea index (AHI) 50±19/hr, body mass index (BMI) 35.0 ±3 kg/m2) were recruited and all completed the study. There were no differences in baseline characteristics between groups. Low-density coronary artery plaque volume decreased with CPAP (from 571±490 to 334±185mm3) and with combination therapy (from 401±145 to 278±126mm3) but not with LWR alone. The change in total plaque volume correlated with the change in time spent below 90% SpO2 (r=0.505, p =0.038).

Conclusions: These data suggest that CPAP therapy but not GLP-1 mediated weight loss may reduce low-attenuation coronary artery plaque volume in OSA