Disclosure: The authors declared no conflict of interest.
Sleep apnea modifies the long-term impact of surgically induced weight loss on cardiac function and inflammation†
Article first published online: 25 MAY 2013
Copyright © 2012 The Obesity Society
Volume 21, Issue 4, pages 698–704, April 2013
How to Cite
Kardassis, D., Grote, L., Sjöström, L., Hedner, J. and Karason, K. (2013), Sleep apnea modifies the long-term impact of surgically induced weight loss on cardiac function and inflammation. Obesity, 21: 698–704. doi: 10.1002/oby.20115
- Issue published online: 25 MAY 2013
- Article first published online: 25 MAY 2013
- Accepted manuscript online: 5 NOV 2012 05:52PM EST
- Manuscript Accepted: 18 SEP 2012
- Manuscript Received: 26 MAR 2012
Obesity is frequently associated with obstructive sleep apnea (OSA). Both conditions are proinflammatory and proposed to deteriorate cardiac function. We used a nested cohort study design to evaluate the long-term impact of bariatric surgery on OSA and how weight loss and OSA relate to inflammation and cardiac performance.
Design and Methods:
At 10-year follow-up in the Swedish Obese Subjects (SOS) study, we identified 19 obese subjects (BMI 31.2 ± 5.3 kg m−2), who following bariatric surgery at SOS-baseline had displayed sustained weight losses (surgery group), and 20 obese controls (BMI 42.0 ± 6.2 kg m−2), who during the same time-period had maintained stable weight (control group). All study participants underwent overnight polysomnography examination, echocardiography and analysis of inflammatory markers.
The surgery group displayed a lower apnea hypopnea index (AHI) (19.9 ± 21.5 vs. 37.8 ± 27.7 n/h, P = 0.013), lower inflammatory activity (hsCRP 2.3 ± 3.0 vs. 7.2 ± 5.0 mg L−1, P < 0.001), reduced left ventricular mass (165 ± 22 vs. 207 ± 22 g, P < 0.001) and superior left ventricular diastolic function (E/A ratio 1.24 ± 1.10 vs. 1.05 ± 0.20, P = 0.006) as compared with weight stable obese controls. In multiple regression analyses including all subjects (n = 39) and controlling for BMI, the AHI remained independently associated with hsCRP (β = 0.09, P < 0.001), TNF-α (β = 0.03, P = 0.031), IL-6 (β = 0.01, P = 0.007), IL 10 (β = −0.06; P = 0.018), left ventricular mass (β = 0.64, P < 0.001), left atrial area (β = 0.08, P = 0.002), pulmonary artery pressure (β = 0.08, P = 0.011) and E/Ea ratio (β = 0.04, P = 0.021).
Patients with sustained weight loss after bariatric surgery display less severe sleep apnea, reduced inflammatory activity, and enhanced cardiac function. Persisting sleep apnea appears to limit the beneficial effect of weight loss on inflammation and cardiac performance.