Date on Master's Thesis/Doctoral Dissertation


Document Type

Doctoral Dissertation

Degree Name

Ph. D.



Committee Chair

Speck, Barbara Jean

Author's Keywords

Sleep apnea; Obesity; CPAP; Actigraphy; Sleep/wake activity; Energy expenditure


Sleep apnea syndromes; Overweight persons--Health and hygiene; Obesity


Overweight and obesity is a major contributing factor in an estimated 70% of all obstructive sleep apnea (OSA) cases. Approximately five percent of the adult population has OSA, and the numbers continue to soar with the rising prevalence of obesity. As a primary therapy, continuous positive airway pressure (CPAP) has demonstrated improvement in many comorbidities associated with both OSA and obesity. Although anecdotal and clinical references support increased energy, activity, and weight loss as a potential benefit of CP AP treatment, there remains little evidence to endorse CP AP as a significant weight-reduction measure for overweight and obese OSA patients. The purpose of this study was to examine sleep/wake activity and energy expenditure, pre- and post-CP AP treatment, in adult overweight and obese patients with OSA. A prospective, observational, longitudinal study design was employed to assess 24-hour actigraphic measures of sleep/wake activity and energy expenditure prior and subsequent to CPAP therapy. Analysis of variance (ANOVA) using repeated measures was performed to identify overall differences between pre-CP AP and one week post-CPAP and pre-CPAP and one month and post-CPAP sleep activity, wake activity, and 24-hour energy expenditure. Sixty-nine subjects were consented, with a total of 35 subjects completing the study. Data analyses revealed statistically significant mean differences in sleep activity, wake activity, and energy expenditure from pre-CPAP to post-CPAP at one week and one month. At baseline, and continuing through one week post-CPAP and one month post-CPAP, the CPAP compliant group demonstrated less sleep activity, more wake activity, and expended more energy than the CPAP noncompliant group. This study concluded that CP AP use is a statistically significant factor affecting sleep activity time, wake activity time, and energy expenditure. Regardless of CP AP compliance and length of use, the entire post-CPAP group demonstrated more sleep activity, had less wake activity, and burned fewer calories. From a clinical perspective, the results of this study do not support the use of CP AP as a potential weight loss measure in overweight and obese OSA patients, and emphasize the need for the inclusion of behavioral weight management and weight loss strategies in an at-risk population for comorbid illnesses.