Most with sleep apnea still have metabolic syndrome after CPAP therapy

Most patients with obstructive sleep apnea retained their metabolic syndrome diagnosis after CPAP therapy, despite higher rates of reversibility after treatment, according to findings of a randomized trial published in Chest.

“These results underscore the need for combined therapy with CPAP, aiming to maximize metabolic syndrome recovery in parallel with improvements in OSA severity and daytime sleepiness,” Sara Q. C. Giampá, PhD, of the postgraduate program in cardiology at the University of São Paulo, and colleagues wrote.

Researchers conducted the randomized, placebo-controlled TREATOSA-MS trial, which enrolled 100 adults with a recent diagnosis of metabolic syndrome and moderate to severe OSA (mean age, 48 years; 79% men; BMI, 33 kg/m²; mean apnea hypopnea index, 58 events per hour). All patients were randomly assigned to receive CPAP therapy (n = 50) or nasal dilator strips (n = 50) for 6 months. Researchers measured anthropometric variables, blood pressure, glucose and lipid profile before and after each intervention and also measured adiposity biomarkers, body composition, food intake, physical activity, subcutaneous and abdominal fat, and endothelial function.

Mean CPAP adherence was 5.5 hours per night.

At 6 months, most patients with OSA who received CPAP therapy retained their metabolic syndrome diagnosis. The rate of metabolic syndrome reversibility wwas 18% among patients assigned CPAP therapy compared with 4% among patients assigned nasal dilator strips (OR = 5.27; 95% CI, 1.27-35.86; P = .04).

CPAP failed to promote significant reductions in individual components of the metabolic syndrome, as well as weight, hepatic steatosis, lipid profile, adiponectin and leptin in a secondary analysis. However, CPAP therapy promoted a modest reduction in visceral fat and improved endothelial function when adjusted for baseline values.