Treatment adherence was defined by a mean daily PAP use ≥ 4 h; PAP treatment response was defined by a decrease in Epworth score of at least 2 points from baseline to 6-month follow-up; PAP treatment success was defined by a mean daily PAP use ≥ 4 h and a decrease in Epworth score of at least 2 points from baseline to 6-month follow-up. *Adjusted for age, sex, body mass index, Epworth score, apnea-hypopnea index, cardiovascular diseases, marital and occupational status, type of sleep study and study site. CI = confidence interval, e-POSA = exclusive positional sleep apnea, NPOSA = nonpositional sleep apnea, OR = odds ratio, POSA = positional sleep apnea.