Bidirectional Relationships Between Weight Change and Sleep Apnea in a Behavioral Weight Loss Intervention

Objective: To examine the bidirectional relationship between weight change and obstructive sleep apnea (OSA) in the context of a behavioral weight loss intervention. Patients and Methods: Adults who were overweight or obese (N = 114) participated in a 12-month behavioral weight loss intervention from April 17, 2012, through February 9, 2015. The apneahypopnea index (AHI), a marker of the presence and severity of OSA, was assessed at baseline, 6 months, and 12 months. Linear mixed models evaluated the effect of weight change on the AHI and the effect of OSA (AHI >= 5) on subsequent weight loss. Secondary analyses evaluated the effect of OSA on intervention attendance, meeting daily calorie goals, and accelerometer-measured physical activity. Results: At baseline, 51.8% of the sample (n = 59) had OSA. Adults who achieved at least 5% weight loss had an AHI reduction that was 2.1 +/- 0.9 (adjusted mean +/- SE) events/h greater than those with less than 5% weight loss (P<.05). Adults with OSA lost a mean +/- SE of 2.2% +/- 0.9% less weight during the subsequent 6-month interval compared with those without OSA (P = .02). Those with OSA were less adherent to daily calorie goals (mean +/- SE: 25.2% +/- 3.3% vs 34.8% +/- 3.4% of days; P = .006) and had a smaller increase in daily activity (mean +/- SE: 378.3 +/- 353.7 vs 1060.1 +/- 377.8 steps/d; P<.05) over 12 months than those without OSA. Conclusion: Behaviorally induced weight loss in overweight/obese adults was associated with significant AHI reduction. However, the presence of OSA was associated with blunted weight loss, potentially via reduced adherence to behaviors supporting weight loss. These results suggest that OSA screening before attempting weight loss may be helpful to identify who may benefit from additional behavioral counseling. (C) 2018 Mayo Foundation for Medical Education and Research