Objective: To investigate the correlation between the severity of obstructive sleep apnea syndrome (OSAS) and red cell distribution width (RDW) in elderly patients.
Methods: A cross-sectional study was conducted among 311 elderly patients diagnosed with OSAS in the snoring clinic between January, 2015 and October, 2016 and 120 healthy controls without OSAS from physical examination populations in the General Hospital of PLA. The subjects were divided into control group with apnea-hypopnea index (AHI) <5 (n=120), mild OSAS group (AHI of 5.0-14.9; n=90), moderate OSAS group (AHI of 15.0-29.9; n=113) and severe OSAS group (AHI ≥ 30; n=108). The clinical characteristics and the results of polysomnography, routine blood tests and biochemical tests of the subjects were collected. Multiple linear regression analysis was used to examine the correlation between OSAS severity and RDW.
Results: The levels of RDW and triglyceride were significantly higher in severe OSAS group than in the other groups (P < 0.01). The levels of fasting blood glucose and body mass index were significantly higher in severe and moderate OSAS groups than in mild OSAS group and control group (P < 0.05 or P < 0.01). Multiple linear regression analysis showed that AHI was positively correlated with body mass index (β=0.111, P=0.032) and RDW (β=0.106, P=0.029). The area under ROC curve of RDW for predicting the severity of OSAS was 0.687 (P=0.0001).
Conclusions: The RDW increases as OSAS worsens and may serve as a potential marker for evaluating the severity of OSAS.
目的: 探讨老年阻塞性睡眠呼吸暂停综合征(OSAS)严重度与红细胞体积分布宽度(RDW)的关系。
方法: 采取横断面调查, 纳入2015年1月~2016年10月在解放军总医院鼾症门诊确诊为OSAS患者311例(年龄≥ 65岁)为观察组, 其中男性213例, 女性98例。同期入选体检人群排除OSAS的老年人120例为对照组。根据OSAS患者睡眠呼吸暂停低通气指数(AHI)再将观察组分为3组:轻度OSAS组(AHI为5.0~14.9, n=90), 中度OSAS组(AHI为15.0~29.9, n=113), 重度OSAS组(AHI ≥ 30, n=108)。对照组的AHI < 5。收集研究对象的一般资料, 进行多导睡眠监测、静脉抽血查常规、血生化全套指标, 并采用多元线性回归分析, 分析OSAS严重度与RDW的相关性。
结果: 重度OSAS组的RDW、甘油三酯水平高于其他各组(P < 0.01);重度OSAS组和中度OSAS组的空腹血糖水平、体质量指数高于轻度OSAS组和对照组(P < 0.05或P < 0.01)。多元线性回归分析显示, AHI与体质量指数(Beta=0.111, P=0.032)、RDW (Beta=0.106, P=0.029)呈正相关。RDW预测OSAS的严重程度的ROC曲线下面积为0.687(P=0.0001)。
结论: RDW可随着老年OSAS程度的加重而增高, 可能作为老年OSAS患者严重度评估的潜在辅助指标。
Keywords: apnea hypopnea index; elderly patients; obstructive sleep apnea syndrome; red cell distribution width.