Koehnlein T, Schmidt A, Moesenthin M, Dierkes J, Neumann K H, Welte T
Department of Respiratory Medicine, Hannover Medical School, Hannover, Germany.
Clin Nephrol. 2009 Jan;71(1):50-8. doi: 10.5414/cnp71050.
Increased cardiac troponin T (cTnT) and C-reactive protein (CRP) levels predict mortality in patients with end-stage renal disease (ESRD) on maintenance hemodialysis. Obstructive sleep apnea (OSA) is associated with severe cardiac stress and systemic inflammation. We hypothesized that in patients with ESRD elevated levels of cTnT and CRP are consequences of unrecognized OSA.
After diagnostic polysomnography, serum levels of cTnT and CRP were assessed in two groups of patients. The first group with normal renal function which served as a control group, was recruited from routine patient referrals to the sleep laboratory at the University Hospital Magdeburg. The second group consisted of patients with ESRD on thrice-weekly maintenance hemodialysis treatment (hemodialysis group).
After screening, 15 patients in each group were eligible for inclusion. OSA (apnea hypopnea index (AHI) > or = 10) was associated with significantly elevated serum CRP levels of 5.1 +/- 4.9 mg/l in the control group and 11.6 +/- 10.2 mg/l in the hemodialysis group, compared with patients in the respective groups without OSA. In the control group, cTnT levels were below the lower detection limit, independent of OSA severity. Patients with ESRD but without OSA had low cTnT levels, similar to those of patients in the control group (0.014 +/- 0.01 ìg/l), whereas patients with ESRD and OSA had significantly elevated serum cTnT levels (0.38 +/- 0.3 microg/l, p < 0.05).
OSA is associated with higher CRP levels in patients with normal or impaired renal function, but cTnT is elevated in OSA patients with impaired renal function only. In this pilot study, both parameters suggest an important role of sleep related breathing disorders on cardiac stress and chronic inflammation.
心脏肌钙蛋白T（cTnT）和C反应蛋白（CRP）水平升高可预测维持性血液透析的终末期肾病（ESRD）患者的死亡率。阻塞性睡眠呼吸暂停（OSA）与严重的心脏应激和全身炎症相关。我们推测，在ESRD患者中，cTnT和CRP水平升高是未被识别的OSA的结果。
在进行诊断性多导睡眠图检查后，对两组患者的血清cTnT和CRP水平进行评估。第一组为肾功能正常的患者，作为对照组，从马格德堡大学医院睡眠实验室的常规患者转诊中招募。第二组由每周进行三次维持性血液透析治疗的ESRD患者组成（血液透析组）。
筛选后，每组各有15例患者符合纳入标准。与各自组中无OSA的患者相比，OSA（呼吸暂停低通气指数（AHI）≥10）与对照组血清CRP水平显著升高相关，对照组为5.1±4.9mg/l,血液透析组为11.6±10.2mg/l。在对照组中，cTnT水平低于检测下限，与OSA严重程度无关。无OSA的ESRD患者的cTnT水平较低，与对照组患者相似（0.014±0.01μg/l），而患有ESRD和OSA的患者血清cTnT水平显著升高（0.38±0.3μg/l，p<0.05）。
OSA与肾功能正常或受损患者的较高CRP水平相关，但仅在肾功能受损的OSA患者中cTnT升高。在这项初步研究中，这两个参数均表明睡眠相关呼吸障碍在心脏应激和慢性炎症中起重要作用。
