When compared with sleep hygiene counseling, CPAP in addition to sleep counseling improved symptoms among patients with mild obstructive sleep apnea, according to data published in The Lancet Respiratory Medicine.
The researchers included patients aged 18 to 80 years with mild OSA, defined by an apnea-hypopnea index of five to 15 events per hour, using American Academy of Sleep Medicine (AASM) 2007 or 2012 scoring criteria, from 11 sleep centers in the United Kingdom in the multicenter, parallel, randomized controlled MERGE trial. They then randomly assigned patients to 3 months of CPAP plus standard care sleep hygiene counseling or standard care alone.
The primary outcome was change in the vitality scale of the SF-36 questionnaire among patients with mild OSA diagnosed by the AASM 2012 criteria in the intention-to-treat population. Patient eligibility was assessed using respiratory polygraphy.
After 3 months of treatment, the adjusted mean treatment effect of 10 points (95% CI, 7.2-12.8). Similarly, results from a more conservative analysis of covariance (ANCOVA) last-observation-carried-forward analysis also demonstrated a difference in the adjusted mean change in the vitality score with CPAP vs. standard care, with a treatment effect of 7.5 points (P < .0001).