A new study has found that treating obstructive sleep apnea with CPAP therapy increases self-reported physical activity in adults with a history of heart disease.
During a mean follow-up period of 3.7 years, the group treated with CPAP therapy reported approximately 20% higher levels of moderate physical activity compared with the control group. The study also found the CPAP group was more likely to report activity levels consistent with expert recommendations.
"We were pleased to find that our CPAP users reported that they were better able to maintain their levels of activity over the four years of the study, and that they reported fewer limitations in moderate and vigorous activities including those that are important for independent ageing, like walking up the stairs," says study co-author Kelly Loffler, who has a doctorate in biochemistry and molecular biology and is a research fellow at the Adelaide Institute for Sleep Health at Flinders University.
The study is published in the February issue of the Journal of Clinical Sleep Medicine.
Nearly 30 million adults in the US have obstructive sleep apnea, a chronic disease that involves the repeated collapse of the upper airway during sleep. Common warning signs include snoring and excessive daytime sleepiness. A common treatment is CPAP therapy, which uses mild levels of air pressure, provided through a mask, to keep the throat open during sleep.
The Sleep Apnea cardioVascular Endpoints (SAVE) study was an international, randomised controlled trial of patients with a history of cardiovascular disease and sleep apnea who were recruited from diverse socioeconomic and health care settings. This analysis examined activity data among 2,601 participants between the ages of 45 and 75 years. More than 80% of participants were men, about 63% were Asian, and 25% were white.
Participants were randomly assigned to one of two groups: One group was treated with CPAP and usual cardiovascular care, while a second group received only usual care. While there was no specific exercise intervention, participants reported physical activity using the Leisure-Time Exercise Questionnaire at the start of the study and over six, 24 and 48 months.
According to the authors, the increased level of physical activity found in this study would likely convey substantial health benefits over longer periods of time, such as lowering the recurrence of cardiovascular events.
"CPAP represents a useful tool to assist health care providers caring for populations with comorbidities and combined with lifestyle interventions like diet and targeted exercise will likely provide many users with a symptomatic benefit that goes beyond their reported sleep," Dr Loffler says.
The SAVE trial was supported by grants from the National Health and Medical Research Council of Australia and by Respironics Sleep and Respiratory Research Foundation and Philips Respironics. There was no funding for this analysis.
The Sleep Apnea cardioVascular Endpoints (SAVE) trial recruited participants with confirmed cardiovascular disease history and obstructive sleep apnea, 45-75 years old. The 2,687 participants (1,346 randomised to CPAP plus usual care and 1,341 to usual care alone) were followed up for a mean of 3.7 years.
Self-reported physical activity was recorded at baseline, 6, 24, and 48 months using the Godin-Shepard Leisure Time Exercise Questionnaire (LTEQ). We also determined effects on any limitation of physical activity reported on the physical functioning subscale of the 36-item short form questionnaire (SF-36) and proportions of participants reaching guideline recommended physical activity levels.
The paper 'CPAP increases physical activity in obstructive sleep apnea with cardiovascular disease' (2021) by D Stevens, KA Loffler, MP Buman, DW Dunstan, Y Luo, G Lorenzi-Filho, FE Barbe, CS Anderson and D McEvoy' on behalf of the SAVE investigators DOI: 10.5664/jcsm.8792
