AVAPS‐AE, ST ventilation show similar impact on sleep quality in OHS patients

Two months of average volume‐assured pressure support—automated expiratory positive airway pressure (AVAPS‐AE) is comparable to pressure support (ST) ventilation in terms of effect on sleep quality and gas exchange among patients with obesity hypoventilation syndrome (OHS), a recent study has shown.

This prospective multicentre randomized controlled trial compared the impact of 2-month AVAPS-AW ventilation with that of ST ventilation on objective sleep quality in stable patients with OHS. Participants had daytime P_aCO₂ >6 kPa, body mass index ≥30 kg/m², clinical stability for >2 weeks and were naive to home noninvasive ventilation (NIV).

Two independent experts analysed the polysomnography (PSG) data. Sleep quality improvement at 2 months was the primary outcome. Secondary ones included arterial blood gases, health-related quality of life, daytime sleepiness, subjective sleep quality, and compliance to NIV.

Sixty-nine patients were included, of whom 60 had successful NIV setup. Baseline and follow-up PSG were available for 30 patients in the AVAPS-AE group and 26 in the ST group.

P_aCO₂ at baseline was 6.61±0.71 kPa in the AVAPS-AE group and 6.94±0.71 kPa in the ST group (p=0.032). Objective sleep quality indices were not significantly different between the two cohorts. Improvement in P_aCO₂ was also similar between the two groups, with a mean reduction of –0.87 kPa (95 percent confidence interval [CI], –1.14 to 0.50) in patients receiving AVAPS-AE ventilation and 0.87 kPa (95 percent CI, –1.12 to –0.46) in those on ST ventilation (p=0.984).

Mean NIV use was 6.2 h per night in both groups (p=0.93), but patients on AVAPS-AE had shorter NIV setup duration (p=0.012).

“AVAPS‐AE combines an automated positive expiratory pressure to maintain upper airway patency to an automated pressure support with a targeted tidal volume,” the authors said.