Fixed-pressure nCPAP in patients with obstructive sleep apnea (OSA) syndrome and chronic obstructive pulmonary disease (COPD): a 24-month follow-up study

The aim of this study was to investigate the time course of body weight, daytime sleepiness, and functional cardiorespiratory parameters in patients with both chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea syndrome (OSA), after institution of domiciliary nasal continuous positive airway pressure (nCPAP).

Twelve consecutive obese outpatients (mean age = 61 ± 11 years; four women) were evaluated before (baseline) and after 3, 12, and 24 months of nocturnal nCPAP (4 h per night).

At baseline, all patients were hypercapnic and hypoxemic, suffering from night desaturation (T ₉₀ is the percentage of total recording time (TRT) spent with SaO₂ ≤ 90% = 38 ± 2%) and sleepy (Epworth sleepiness scale [ESS] = 16.58 ± 0.86). Three months after the implementation of nCPAP, daytime PaCO₂ and PaO₂ improved up to 45.1 ± 0.9 and 69.0 ± 1 mmHg, respectively; mean pulmonary artery pressure (MPAP) decreased from 24.7 ± 1.1 to 19.2 ± 04 mmHg. All other variables showed progressive improvements up to 12 months. At 3 and 12 months, mean body mass index was slightly decreased (to 31.6 ± 0.2 and 30.7 ± 0.1 kg/m², respectively); daytime sleepiness, nocturnal O₂ desaturation, and maximal inspiratory pressure were also improved and thereafter remained stable.

In conclusion, in our patients with both severe OSA and mild-to-moderate COPD, arterial blood gasses and MPAP improved and stabilized after 3 months of nCPAP therapy, with the greatest improvements being in ESS score, T ₉₀, and maximal inspiratory force from 3 up to 12 months; these parameters remained stable over the following 12 months. Finally, our data support early treatment with nCPAP in such patients.