The relationship between neutrophil to lymphocyte ratio, endothelial function, and severity in patients with obstructive sleep apnea.
BACKGROUND
Obstructive sleep apnea (OSA) is characterized by repetitive intermittent hypoxia and reoxygenation during sleep with elevated oxidative stress and promotes the development of atherosclerosis, as demonstrated by vascular dysfunction and chronic inflammation. An increased neutrophil to lymphocyte ratio (NLR) has been recognized to be a novel inflammatory biomarker for systemic inflammation.


OBJECTIVE
We evaluated whether the NLR reflects the severity of OSA and if continuous positive airway pressure (CPAP) treatment ameliorates the endothelial function and NLR in patients with OSA.


METHODS
We enrolled 95 patients with suspected OSA and 29 patients who received CPAP therapy for 3 months. We evaluated the number of endothelial progenitor cells (EPCs) and NLR, the levels of nitric oxide (NOx) and asymmetric dimethylarginine (ADMA), and the endothelial function according to the flow-mediated dilatation (FMD) before and after CPAP treatment.


RESULTS
The levels of apnea-hypopnea index demonstrated an inverse relationship with the FMD and a positive relationship with the NLR. Moreover, NLR is an independent factor suggested for the presence of severe OSA. CPAP therapy increased the levels of EPC and NOx and decreased the level of ADMA. CPAP treatment also improved the FMD and decreased the NLR.


CONCLUSIONS
NLR and endothelial dysfunction significantly correlates with the severity of OSA and FMD and other biochemical parameters improved and NLR decreased significantly after CPAP treatment.
Department of Advanced Cardiology, Saga University, Saga, Japan. Electronic address: junoyama@cc.saga-u.ac.jp.
Jun-ichi
J
Oyama
Department of Cardiovascular Medicine, Saga University, Saga, Japan.
Daisuke
D
Nagatomo
Department of Cardiovascular Medicine, Saga University, Saga, Japan.
Goro
G
Yoshioka
Department of Cardiovascular Medicine, Saga University, Saga, Japan.
Ayumu
A
Yamasaki
Department of Cardiovascular Medicine, Saga University, Saga, Japan.
Kazuhisa
K
Kodama
Department of Cardiovascular Medicine, Saga University, Saga, Japan.
Michio
M
Sato
Department of Cardiovascular Medicine, Saga University, Saga, Japan.
Hiroshi
H
Komoda
Department of Cardiovascular Medicine, Saga University, Saga, Japan.
Toshiyuki
T
Nishikido
Department of Cardiovascular Medicine, Saga University, Saga, Japan.
Aya
A
Shiraki
Department of Cardiovascular Medicine, Saga University, Saga, Japan.
Koichi
K
Node
D000328:Adult; D000368:Aged; D001120:Arginine / Q000031:analogs & derivatives; D015415:Biomarkers / Q000097:blood; D045422:Continuous Positive Airway Pressure; D066026:Endothelial Progenitor Cells / Q000378:metabolism; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D006801:Humans; D018655:Lymphocyte Count; D008214:Lymphocytes / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000378:metabolism*; D009569:Nitric Oxide / Q000097:blood; D011446:Prospective Studies; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000097:blood* / Q000503:physiopathology / Q000628:therapy
D015415:Biomarkers; D009569:Nitric Oxide; C018524:N,N-dimethylarginine; D001120:Arginine
Endothelial progenitor cell; Flow-mediated dilatation; Neutrophil to lymphocyte ratio; Sleep apnea syndrome