Introduction: Obstructive sleep apnea (OSA) and severe obesity share a common pathophysiological phenomenon, systemic and tissue hypoxia. Hypoxaemia modifies microRNA expression, particularly, extracellular vesicles microRNAs which are involved in the progression of cardiovascular diseases, metabolic syndrome and cancer. We aim to evaluate extracellular vesicle miRNAs among patients with severe obesity with and without OSA and the effect of OSA and severe obesity treatment: continuous positive airway pressure (CPAP) and bariatric surgery.
Methods: Patients were selected from the Epigenetics Modification in Morbid Obesity and Obstructive Sleep Apnea (EPIMOOSA) study (NCT03995836), a prospective observational study of patients undergoing bariatric surgery. Patients were divided into OSA (Apnea-hyponea index (AHI) > 10) and non-OSA (AHI < 10). Patients with OSA were treated with CPAP for 6 months. Then, all patients had bariatric surgery and re-evaluated 12 months later. At each visit, blood samples were obtained for biobanking. Subsequently, extracellular vesicles were extracted, and then, miRNA expression was analysed.
Results: 15 patients with OSA and 9 without OSA completed the protocol. At baseline, patients with OSA showed higher miR16, miR126 and miR320 (p < 0.05) and lower miR223 expression (p < 0.05) than those without OSA. In patients with severe obesity and OSA, after 6 months with CPAP, we observed a significant decrease in miR21 (p < 0.01), miR126 (p < 0.001) and miR320 (p < 0.001), with no changes in any miRNA in patients without OSA. No changes were detected in any miRNA after 6 months of bariatric surgery in patients with or without OSA.
Conclusion: Co-existance of OSA and severe obesity alters the profile of extracellular vesicle miRNAs. Bariatric surgery and weight loss did not reverse this effect meanwhile the treatment with CPAP in patients with severe obesity and OSA showed a recovery outcome in those extracellular vesicle miRNAs. Those facts remark the need for OSA screening in patients with severe obesity.
Clinical trial registration: The study has also been registered at ClinicalTrials.gov identifier: NCT03995836.
© 2022. The Author(s), under exclusive licence to Springer Nature Limited.