Änderung der körperlichen Aktivität bei Patienten mit obstruktiver Schlafapnoe durch die Therapie mit Continous Positive Airway Pressure

Introduction: Patients who are treated with continuous positive airway pressure (CPAP) show an increased level of concentrativeness, agility and vigilance. But does their level of physical activity also change? Do patients treated with CPAP move more than patients without CPAP treatment? We examined those questions in the present study, assuming that after treatment with CPAP, the physical activity during daytime would increase. We also assumed a decline of physical activity at night as a result of less movements due to less arousal with CPAP therapy. Method: The study was conducted with 15 patients. Included were patients with a body mass index > 25, an apnoea/hypopnoea index > 20 and without severe co-morbidities like stroke, heart failure or psychiatric diseases. During the study the situation of living was not to change remarkably (i.e. no vacancies, long illness or significant change of working conditions). Physical activity was continuously recorded two weeks before und four weeks after treatment with CPAP. We used an activity monitor (Actitrac, Somnomedics GmbH, Kist) worn on the wrist of the non-dominant hand. Physical activity was counted in mG. During the measurement period the patients kept a sleep log and evaluated their subjective tiredness daily with the Epworth sleepiness scale (ESS).The evaluated parameters were physical activity by day and by night, duration of sleep, duration of time spent awake, sleep efficiency, general sleepiness at daytime during the course of the four weeks under CPAP, correlation between use of CPAP and physical activity. In the following we concentrate on the change of daytime activity and the changes of activity during sleep. Statistical analysis was performed with the Statistical Package for Social Sciences (SPSS), using the Wilcoxon test. Results: The mean age of the patients was 59,6 years. The youngest patient was 33 years old, the oldest was 77 years old. The mean BMI was 35. One patient used CPAP for less than 4 hours per night, so this recording was excluded from the analysis. The daytime activity after CPAP was 22% higher than before therapy, a significant increase. The activity during sleep was lower than before, but this result was not statistically significant. Discussion: For patients with sleep apnoea, daytime physical activity reaches a higher level when CPAP-therapy is applied. The amelioration of the subjective tiredness corresponds with the increase of physical activity. Actigraphy is a good method to measure the change of physical activity in patients with OSA over a period of several weeks.