Continuous positive airway pressure effects on energy expenditure, intake, hormonal regulation, and body composition: a randomized trial

Registry: ClinicalTrials.gov; Name: Validation of Sleep Healthcare System; URL: https://clinicaltrials.gov/study/NCT04252482; Identifier: NCT04252482. Statement of Significance The physiological basis and clinical relevance of weight gain following CPAP therapy remain insufficiently defined. This study found that CPAP-induced weight gain was probably primarily due to increases in FFM, without measurable changes in REE, physical activity, or significant increases in reported caloric intake. Given the potential underestimation in dietary reporting, the observed gain-together with hormonal and behavioral changes-suggests a subtle positive energy balance. These findings indicate that post-CPAP weight gain may not reflect adverse metabolic effects and highlight the value of assessing body composition, rather than weight alone, in clinical follow-up.