Hospital Universitari Arnau de Vilanova, Respiratory Diseases Research Unit, IRB Lleida, Rovira Roure, 80, 25198 Lleida, Spain.
Respir Med. 2011 Dec;105(12):1954-60. doi: 10.1016/j.rmed.2011.08.014. Epub 2011 Sep 1.
Obstructive sleep apnea (OSA) is related to obesity and metabolic disorders. The main clinical symptoms are excessive daytime sleepiness (EDS) and snoring. However, not all patients with OSA manifest EDS. Hypocretin-1, neuropeptide Y, leptin, ghrelin and adiponectin are implicated in both metabolic and sleep regulation, two conditions affected by OSA. We hypothesized that levels of these peptides may be related to EDS in OSA patients.
We included 132 patients with EDS, as defined by an Epworth Sleepiness Scale (ESS) score ≥ 13 (mean ± SD, 15.7 ± 2.3) and 132 patients without EDS as defined by an ESS score ≤ 9 (6.5 ± 1.9). All patients had an apnea-hypopnea index (AHI) ≥ 20 h(-1). Both groups were matched for gender (males; 83.3% vs. 85.6%), age (50.15 ± 11.2 yrs vs. 50.7 ± 9.9 yrs), body mass index (BMI) (31.8 ± 5.6 kg m(-2) vs. 32.1 ± 4.8 kg m(-2)), and apnea-hypopnea index (AHI) (45.5 ± 19.1 h(-1) vs. 43 ± 19.2 h(-1)).
OSA patients with EDS showed significantly higher plasma hypocretin-1 levels (p < 0.001) and lower plasma ghrelin levels (p < 0.001) than OSA patients without EDS. There were no statistically significant differences in neuropeptide Y (p = 0.08), leptin (p = 0.07) and adiponectin (p = 0.72) between the two groups. In the multiple linear regression model ESS score was associated with plasma levels of hypocretin-1, ghrelin and total sleep time.
Our study shows that EDS in patients with OSA is associated with increased circulating hypocretin-1 and decreased circulating ghrelin levels, two peptides involved in the regulation of body weight, energy balance, sympathetic tone and sleep-wake cycle. This relationship is independent of AHI and obesity (two key phenotypic features of OSA).
阻塞性睡眠呼吸暂停（OSA）与肥胖和代谢紊乱有关。主要的临床症状是日间嗜睡（EDS）和打鼾。然而，并非所有 OSA 患者都表现出 EDS。下丘脑分泌素-1、神经肽 Y、瘦素、胃饥饿素和脂联素均参与代谢和睡眠调节，这两种情况均受 OSA 影响。我们假设这些肽的水平可能与 OSA 患者的 EDS 有关。
我们纳入了 132 名 EDS 患者，其定义为 Epworth 嗜睡量表（ESS）评分≥13（平均值±标准差，15.7±2.3），以及 132 名 ESS 评分≤9 的非 EDS 患者（6.5±1.9）。所有患者的呼吸暂停-低通气指数（AHI）≥20 h(-1)。两组在性别（男性；83.3%对 85.6%）、年龄（50.15±11.2 岁对 50.7±9.9 岁）、体重指数（BMI）（31.8±5.6 kg m(-2)对 32.1±4.8 kg m(-2)）和呼吸暂停-低通气指数（AHI）（45.5±19.1 h(-1)对 43±19.2 h(-1)）方面相匹配。
与无 EDS 的 OSA 患者相比，有 EDS 的 OSA 患者的血浆下丘脑分泌素-1水平显著升高（p<0.001），血浆胃饥饿素水平显著降低（p<0.001）。两组间神经肽 Y（p=0.08）、瘦素（p=0.07）和脂联素（p=0.72）差异无统计学意义。在多元线性回归模型中，ESS 评分与下丘脑分泌素-1、胃饥饿素和总睡眠时间的血浆水平相关。
我们的研究表明，OSA 患者的 EDS 与循环中下丘脑分泌素-1水平升高和胃饥饿素水平降低有关，这两种肽均参与体重调节、能量平衡、交感神经张力和睡眠-觉醒周期。这种关系独立于 AHI 和肥胖（OSA 的两个关键表型特征）。
