Ventilatory support or respiratory muscle training as adjuncts to exercise in obese CPAP-treated patients with obstructive sleep apnoea: a randomised controlled trial.

BACKGROUND

Obstructive sleep apnoea (OSA) and obesity are interdependent chronic diseases sharing reduced exercise tolerance and high cardiovascular risk.

INTERVENTION: A 3-month intervention with innovative training modalities would further improve functional capacity and cardiovascular health than usual cycle exercise training in already continuous positive airway pressure (CPAP)-treated obese patients with OSA.

METHODS

Fifty three patients (35<body mass index (BMI) <45 kg/m2) were randomly allocated to exercise training on a cycle ergometer, either alone (ERGO) or with respiratory muscle training (ERGO+RMT) or non-invasive ventilation (ERGO+NIV). Changes in 6 min walking distance (primary outcome), aerobic capacity (VO2peak), cardiovascular parameters, body composition and sleep quality were evaluated.

MEASUREMENTS AND MAIN

RESULTS

All training modalities increased 6 min walking distance without differences between groups (P=0.97). ERGO+NIV and ERGO+RMT led to significantly higher improvement in VO2peak compared with ERGO (3.1 (95% CI 1.6 to 4.6) vs 2.3 (0.8 to 3.7) vs 0.5(-1.0 to 1.9) mL/min/kg, respectively, P=0.04) and ERGO+NIV significantly reduced self-measured blood pressure compared with ERGO+RMT and ERGO (systolic: -9.5 (95% CI -14.1 to -4.9) vs -13 (-5.8 to 3.1) vs -0.7 (-5.1 to 3.8) mm Hg, respectively, P=0.01). Waist and neck circumferences were reduced after ERGO+NIV compared with ERGO+RMT and ERGO (P=0.01).

CONCLUSIONS

Combining RMT or NIV with cycling exercise training failed to provide further improvement in functional capacity as compared with cycling exercise training alone. However, the combination of NIV and exercise training demonstrated superiority for improving cardiometabolic risk factors in obese CPAP-treated patients with OAS.

TRIAL REGISTRATION NUMBER: Results, NCT01155271.