阻塞性睡眠呼吸暂停低通气综合征患者血浆食欲素A水平的变化及意义

目的探讨阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者血浆食欲素A的变化及意义。方法选择OSAHS并肥胖患者30例(OSAHS组)、单纯肥胖者30例(单纯肥胖组)和健康成人20名(正常对照组)。其中OSAHS组和单纯肥胖组的体重指数(BMI)均≥25kg/m2且差异无统计学意义。所有受试者均接受多导睡眠仪监测,采用层析及放射免疫法测定血浆食欲素A的水平。结果OSAHS组血浆食欲素A水平[(9.0±1.8)ng/L]显著高于单纯肥胖组[(7.2±1.4)ng/L,P<0.01]及正常对照组[(6.7±1.6)ng/L,P<0.01]。OSAHS组血浆食欲素A水平与呼吸暂停低通气指数(AHI)、微觉醒指数(arousalindex)呈正相关(r=0.639、0.435,P均<0.05),与最低血氧饱和度(LSaO2)、平均血氧饱和度(MSaO2)呈负相关(r=-0.521、-0.589,P均<0.01)。OSAHS组及单纯肥胖组血浆食欲素A水平与BMI无相关性(r=0.132,P>0.05)。结论OSAHS患者血浆食欲素A水平升高,其原因可能与患者夜间反复发作性低氧有关,且食欲素A在调节睡眠觉醒的过程中可能发挥了重要的作用。

The changes and implications of plasma orexin-A levels in patients with obstructive sleep apnea-hypopnea syndrome

OBJECTIVE: To explore the changes and implications of plasma orexin-A levels in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). METHODS: Polysomnography was performed in 30 obese OSAHS patients (OSAHS group), 30 obese subjects (obese group) and 20 normal healthy adults (control group). In both the OSAHS group and the obese group the body mass index (BMI) was higher than 25, and there was no significant difference in BMI. The plasma was deproteinized by chromatography, and the level of orexin-A was determined by radioimmunoassay. RESULTS: The plasma orexin-A level in the OSAHS group [(9.0 +/- 1.8) ng/L] was significantly higher than those in the obese group [(7.2 +/- 1.4) ng/L, P < 0.01] and the control group [(6.7 +/- 1.6) ng/L, P < 0.01] respectively. Plasma orexin-A levels in patients with OSAHS correlated positively with the AHI (r = 0.639, P < 0.01), and the arousal index (r = 0.435, P < 0.05), but correlated negatively with the lowest oxygen saturation (LSaO(2)) (r = -0.521, P < 0.01) and the mean oxygen saturation (MSaO(2)) (r = -0.589, P < 0.01). The BMI in the OSAHS group and the obese group did not correlate significantly with the orexin-A levels (r = 0.132, P > 0.05). CONCLUSIONS: The plasma orexin-A levels in OSAHS patients are increased which may be caused by repeated nocturnal hypoxia due to OSAHS. Orexin-A may play a crucial role in the regulation of the sleep-arousal process.