Effect of oral appliance on endothelial function in sleep apnea.
OBJECTIVE
This study evaluated the effects of mandibular advancement device (MAD) on serum levels of nitric oxide derivatives and endothelial function by endothelium-dependent flow-mediated dilation (FMD) in obstructive sleep apnea syndrome (OSAS).


METHODS
Thirty patients with moderately severe-to-severe OSAS who desired MAD and 15 healthy controls were prospectively enrolled. FMD was measured by high-resolution B-mode ultrasonography, while serum NO x level from peripheral blood samples was measured by ELISA. All subjects participated in the sleep studies, which were repeated 2 months after MAD in OSAS patients.


RESULTS
Serum NO x level and FMD were lower in patients with OSAS than in controls prior to MAD. Serum NO x levels in 19 of 30 patients with OSAS, the designated MAD responders, increased from 11.8 ± 5.8 μM pre-MAD to 22.7 ± 4.9 μM post-MAD. The FMD increased from 5.9 ± 4.6 pre-MAD to 10.5 ± 4.8 post-MAD. For the 11 unresponsive patients, serum NO x and FMD remained impaired after MAD.


CONCLUSIONS
Successful treatment of OSAS with MAD can restore serum levels of NO x and FMD.


CONCLUSIONS
Endothelial function can be improved following effective treatment of OSAS using MAD.
Chest Division, Department of Internal Medicine, Mackay Memorial Hospital, #92, Section 2, Chung Shan North Road, Taipei, Taiwan, cclin@ms2.mmh.org.tw.
Ching-Chi
CC
Lin
Huey-Yuan
HY
Wang
Chung-Hsin
CH
Chiu
Shwu-Fang
SF
Liaw
D004730:Endothelium, Vascular / Q000503:physiopathology*; D006801:Humans; D019186:Mandibular Advancement / Q000295:instrumentation*; D012891:Sleep Apnea Syndromes / Q000503:physiopathology*