Effect of Nasal CPAP therapy on functional respiratory parameters and cardiopulmonary exercise test in Obstructive Sleep Apnea Syndrome

Nasal continuous airway pressure (nCPAP) treatment is an effective treatment modality for patients with OSAS. It can improve physical and mental functions by reducing daytime hypersomnolence, arousal index and sleep fragmentations. To our knowledge, the exercise limitation in patients with OSAS by using cardiopulmonary exercise test (CPET) have been shown before, but the effects of treatment by nCPAP on functional respiratory parameters and CPET in OSAS has never been studied in our country. The purpose of this study was to evaluate whether pulmonary functions, exercise limitation confirmed with CPET and quality of life can be improved after eight weeks of nCPAP treatment.In our case group, we found an exercise limitation with CPET before nCPAP, an improvement in exercise capacity after nCPAP treatment for eight weeks. But exercise capacity did not totally return to normal level. We also found that nCPAP can help to control blood pressure and improve inspiratory and expiratory muscle forces. Patients undergoing nCPAP scored better in physical function, role-physical, general health, energy/vitality, social function, role-emotional, mental health, physical component summary and mental component summary using the SF-36 tool. There were no changes in pulmonary volumes and spirometric parametres indipendent of body mass index (BMI). There was a decrease in FEV1, which was statistically important.In conclusion, OSAS may lead to exercise limitation. Nasal CPAP treatment is effective in reducing exercise limitation, can help to control blood pressure and improves respiratory muscle strength. Nasal CPAP can also improve the quality of life scores in OSA patients without any comorbidity or with comorbidities under control. Our findings may suggest that these changes are the results of improvements in patients? cardiac function, daytime somnolence and fitness.