Plasma B-type natriuretic peptide level is associated with left ventricular hypertrophy among obstructive sleep apnoea patients.
OBJECTIVE
To examine whether increased plasma levels of B-type natriuretic peptide (BNP) are associated with cardiac structural and functional abnormalities in obstructive sleep apnoea (OSA) patients, taking into consideration the confounding effect of obesity.


METHODS
In a cross-sectional study, polysomnography, echocardiography and the measurement of the serum levels of BNP were performed in 235 consecutive subjects (age 52 +/- 14 years) visiting our sleep clinic. Left ventricular hypertrophy (LVH) [left ventricular mass index (LVMI) > or = 125 g/m in men, and > or = 110 g/m in women] and cardiac diastolic function (E/A ratio) were determined by echocardiography.


RESULTS
The LVMI, prevalence rate of LVH and body mass index (BMI) were higher, and the E/A ratio lower in the subjects with severe OSA (apnoea-hypopnoea index > or = 30/h, n = 146, LVH 80%) than in those with mild to moderate OSA (n = 89, LVH 35%; P < 0.01), although plasma BNP levels were similar in the two groups. Although the log-transformed plasma BNP level showed a negative correlation with BMI, the results of binary logistic regression analysis demonstrated that the quintile value of BNP was an independent significant variable for the identification of LVH (adjusted odds ratio in quintile 5 = 4.01, 95% confidence interval 1.18-13.70, P < 0.01), even after adjusting for obesity and other risk factors.


CONCLUSIONS
An increased likelihood of cardiac structural and functional abnormalities was observed with increasing severity of OSA. Increased plasma levels of BNP do seem to reflect an increased likelihood of LVH in patients with severe OSA.
Usui
Yasuhiro
Y
Department of Cardiology, Tokyo Medical University, Shinjuku-ku, Tokyo, Japan.
Tomiyama
Hirofumi
H
Hashimoto
Hideki
H
Takata
Yoshifumi
Y
Inoue
Yuichi
Y
Asano
Kihiro
K
Kurohane
Saiko
S
Shiina
Kazuki
K
Hirayama
Yoji
Y
Yamashina
Akira
A
D015992:Body Mass Index; D003430:Cross-Sectional Studies; D004452:Echocardiography; D005260:Female; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D017286:Polysomnography; D015203:Reproducibility of Results; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology*; D016277:Ventricular Function, Left
D020097:Natriuretic Peptide, Brain