The impact of split-night versus traditional sleep studies on CPAP compliance

Background Split-night polysomnography allows for the diagnosis of obstructive sleep apnea and titration of continuous positive airway pressure in a single study. However, there is concern that split-night studies do not provide sufficient time for optimal continuous positive airway pressure (CPAP) titration, which may lead to a poor initial experience with CPAP and potentially, worse adherence. Our goal was to determine whether CPAP use, after a split-night examination, is comparable to the use following separate diagnostic and titration studies. Methods We included consecutive patients presenting for follow-up 4-6 weeks after initiating CPAP therapy. Objective measures of CPAP use were recorded, and adherence to therapy was analyzed based on the initial method of diagnosis and titration-split-night versus dual-night study. Results A total of 400 patients (78% male, mean age 47± 8 years) were included. Among the patients, 267 and 133 underwent split- and dual-night studies, respectively. The groups were similar at baseline; however, the average apnea-hypopnea index was significantly higher in the splitnight group. Mean number of days between diagnosis and titration in the dual-night group was 80.5 days. There was no difference in therapeutic adherence between groups as measured by percentage of nights used (78.7% vs 77.5%; p=0.42), hours per night used (3.9 vs 3.9; p=0.95), or percentage of patients using continuous positive airway pressure for >4 hours per night for >70% of nights (52.9% vs 51.8%; p=0.81). There was no difference in use after adjusting for severity of disease. Conclusions Split-night polysomnography does not adversely affect short-term continuous positive airway pressure adherence in patients with obstructive sleep apnea.