Noninvasive ventilation improves heart function in obesity hypoventilation syndrome
Bi-level noninvasive ventilation (NIV) in patients with obesity hypoventilation syndrome (OHS) can help reverse left ventricular hypertrophy, according to a study from Spain.
Patients with OHS treated with continuous positive airway pressure (CPAP) did not experience the same benefits.
Bi-level NIV (commonly referred to by its most popular trade name, BiPAP) is known to improve pulmonary hypertension, but any effects on left heart remodeling have been unclear.
Investigators performed a post hoc analysis of the randomized trial known as the Pickwick study, which had compared bi-level NIV with CPAP and lifestyle changes on cardiac function (as observed by echocardiography) in 221 patients with OHS.
BiPAP reduced pulmonary artery pressure and improved left ventricular remodeling better than lifestyle modification or CPAP. Findings were reported in Thorax.
Patients receiving bi-level NIV also showed small improvements in lung function and exercise tolerance (FEV1 and 6-minute walk distance), and about one-third of patients with baseline pulmonary hypertension had resolution of their pulmonary artery pressures to normal levels (62% to 42%).
Obesity hypoventilation syndrome is a far more serious condition than obstructive sleep apnea, though the two often co-exist. Patients with untreated OHS are at increased risk for hospitalization, respiratory failure, cardiovascular disease, and sudden death, compared to patients with simple OSA.
Bi-level NIV is superior to CPAP at improving respiratory parameters in patients with OHS, but it's unknown whether that leads to clinically relevant benefits (survival, avoiding hospitalization, etc).
The study was short-term (only two months) and longer studies will be required to determine if the benefits are sustained or associated with meaningful clinical outcomes.