Background/Rationale:~Obstructive sleep apnea/hypopnea (OSAH) is a common chronic disease that is associated with daytime sleepiness, impaired health-related quality of life (QOL), and increased risk of hypertension and cardiovascular disease. The most common treatment is continuous positive airway pressure (CPAP), although adherence to CPAP is poor in more than one-third of patients. Weight loss can clearly lessen the severity of OSAH, but although short-term dietary weight loss can often be achieved it is difficult to maintain. Regular aerobic exercise is associated with a lower prevalence of OSAH in observational studies after adjustment for body habitus, and in two small clinical trials moderate exercise was associated with a substantial decrease in OSAH severity despite little or no weight loss. Demonstrating that dietary weight loss and moderate physical activity, promoted in the home setting, independently improve OSAH severity will have a major impact on the therapeutic approach to OSAH, a disease that is highly prevalent in the VA population.~Objective:~The investigators hypothesize that both moderate-intensity physical activity and dietary weight loss will independently reduce OSAH severity and improve QOL.~Methods:~The proposed study is a randomized clinical trial designed to test the independent effects of the physical activity and diet interventions, with an attention control intervention for subjects not assigned to either active intervention. Subjects will be male and female Veterans with a BMI over 24 kg/m2, with a physician diagnosis of OSAH and apnea-hypopnea index (AHI) >10/hr. The interventions will last six months.
This project is investigating whether both moderate-intensity physical activity and dietary weight loss will independently reduce sleep apnea symptoms and improve quality of life.