Impact of CPAP treatment for a short period in moderate-to-severe OSAS patients: a randomized double-blind clinical trial.

INTRODUCTION: Obesity is the most frequent reversible aggravating factor of obstructive sleep apnea syndrome, OSAS, with physical activity very important for its control. Continuous positive air pressure during sleep is the "gold standard" treatment for OSAS.

OBJECTIVE: we aimed to investigate if the use of CPAP for a short period (7 days), would improve sleep quality, daytime sleepiness, and the disposition for physical activity.

METHODS: Eighty OSAS patients were randomly assigned as follows: group I - CPAP with a steady pressure of 4 cm H2 O; group II - ideal therapeutic pressure. After filling out the questionnaires related to the studied variables (International physical activity questionnaire long-form, Epworth sleepiness scale, Pittsburgh sleep quality index), patients underwent a baseline pulmonary function test and CPAP titration. After CPAP therapy for 4≥ hours a night for 7 consecutive days, patients returned and filled out new (International physical activity questionnaire long-form, Epworth sleepiness scale, Pittsburgh sleep quality index) forms. New spirometry was carried out.

RESULTS: 39 patients completed the study. The mean age was 52 ± 11 years old and 28 patients (71.79%) were obese. Both groups were similar for all variables studied at baseline. After CPAP use, patients of group II presented more significant improvements (p <  0.05) for sleep quality and diurnal sleepiness. Time spent with physical activities did not change. Spirometric data were at normal range at baseline. Solely the variable FEF 25%-75% was significantly enhanced (p <  0.05) in group II.

CONCLUSION: CPAP therapy for 1 week, with ideal pressure, improves daytime sleepiness and sleep quality, enhances pulmonary function, but does not change the mean time spent with physical activities.