Funding: This work was conducted with support from Harvard Catalyst, the Harvard Clinical and Translational Research Center (National Center for Research Resources and the National Center for Advancing Translational Science, National Institutes of Health Award 8UL1TR000170-05 and financial contributions from Harvard University and its affiliated academic healthcare centres). The content is solely the responsibility of the authors and does not necessarily represent official views of Harvard Catalyst, Harvard University and its affiliated academic health centres, or the National Institutes of Health. This work was supported by the National Institutes of Health [5R01HL048531-16, R01 HL085188-02, R01 HL090897-01A2, 1R01HL110350-01A1, R01HL110350-01, K24HL093218-01A1 and P01 HL 095491] and the American Heart Association [0840159N].
Pilot study of the effects of bariatric surgery and continuous positive airway pressure treatment on vascular function in obese subjects with obstructive sleep apnoea
Article first published online: 4 SEP 2013
© 2013 The Authors; Internal Medicine Journal © 2013 Royal Australasian College of Physicians
Internal Medicine Journal
Volume 43, Issue 9, pages 993–998, September 2013
How to Cite
Bakker, J. P., Balachandran, J. S., Tecilazich, F., DeYoung, P. N., Smales, E., Veves, A. and Malhotra, A. (2013), Pilot study of the effects of bariatric surgery and continuous positive airway pressure treatment on vascular function in obese subjects with obstructive sleep apnoea. Internal Medicine Journal, 43: 993–998. doi: 10.1111/imj.12224
Conflict of interest: J. P. Bakker has been a co-investigator on studies funded by Apnex and Philips Respironics. A. Malhotra has consulted for Philips Respironics, Sleep HealthCenters, Sleep Group Solutions, Apnicure, Apnex and Pfizer, but has relinquished all outside personal income since May 2012.
- Issue published online: 4 SEP 2013
- Article first published online: 4 SEP 2013
- Accepted manuscript online: 26 JUN 2013 04:17AM EST
- Manuscript Accepted: 13 JUN 2013
- Manuscript Received: 1 APR 2013
- National Institutes of Health. Grant Numbers: 5R01HL048531-16, R01 HL085188-02, R01 HL090897-01A2, 1R01HL110350-01A1, R01HL110350-01, K24HL093218-01A1, P01 HL 095491
- American Heart Association. Grant Number: 0840159N
- obstructive sleep apnoea
The mechanisms by which obesity and obstructive sleep apnoea (OSA) may contribute to endothelial dysfunction are unclear.
We sought to follow up a sample of obese subjects undergoing either bariatric surgery or continuous positive airway pressure (CPAP) therapy to treat OSA. We hypothesised improved vascular function with both therapeutic approaches, consistent with a reversible OSA effect on the circulation.
Twenty-seven obese (BMI ≥30 kg/m2) subjects with OSA underwent either bariatric surgery without CPAP (n = 12, median BMI 43.7 kg/m2 IQR 9.4) or CPAP (n = 15, median BMI 33.8 kg/m2 IQR 6.6). Polysomnography and vascular testing (flow-mediated dilation of the brachial artery measured with high-resolution ultrasound, endothelium-dependent change in skin blood flow measured with laser Doppler flowmetry, and arterial stiffness measured with applanation tonometry) took place at baseline and after 6 months.
Both groups showed significant improvements in the apnoea–hypopnea index and overnight oxygen saturation. Endothelium-dependent microvascular reactivity was 45.6% (IQR 37.5) at baseline in the CPAP group, which increased to 69.1% (IQR 62.3) post-treatment (P < 0.05). No significant changes were observed in the surgery group, despite significant weight loss (post-surgery BMI 32.7 kg/m2 IQR 8.6 (P < 0.01); no change in BMI was observed in the CPAP group. There were no significant changes in brachial artery flow-mediated dilation in either group.
This pilot study demonstrates that 6 months of CPAP may be sufficient to improve endothelium-dependent microvascular reactivity, while substantial surgically induced weight loss did not result in improvements. Further research should be directed towards comparative effectiveness trials using these novel surrogate outcomes, as well as hard cardiovascular outcomes.