Supplementary Material for: Association between Obstructive Sleep Apnea and Acute Kidney Injury in Critically Ill Patients: A Propensity-Matched Study

Background/Aims: Obstructive sleep apnea (OSA) is a
known risk factor for chronic kidney disease (CKD); however, its
association with acute kidney injury (AKI) is not well documented. We
aimed to study whether OSA is associated with the risk of AKI in the
intensive care unit (ICU) setting. Methods: All
consecutive adult Olmsted County, MN residents who were admitted in Mayo
Clinic ICUs from January 1, 2010 to December 31, 2010 were screened.
Chronic and acute risk factors were collected within the first 48 h of
ICU admission. Logistic regression and propensity score matching were
used to examine crude and adjusted associations of OSA with AKI. Results:
Among 1,259 enrolled ICU patients, 183 patients had a diagnosis of OSA
prior to the index ICU admission. Compared with non-OSA patients, the
incidence of AKI in OSA patients was more frequent (41 vs. 57%, p <
0.001). In univariate analysis, it was found that CKD, age, gender,
Caucasian race, congestive heart failure, cerebrovascular disease,
diabetes mellitus, body mass index, and OSA were associated with AKI. In
the multivariate model, following adjustment for age, gender, race, and
chronic and acute risk factors, OSA was found to have an independent
association with AKI (OR 1.53; 95% CI 1.04-2.24; p = 0.031).
Among 176 propensity score matched pairs, there was a significant
difference in the incidence of AKI between the OSA and non-OSA groups
(OR 1.54; 95% CI 1.01-2.35; p = 0.04). Conclusions: The history of OSA diagnosed by polysomnography is associated with higher risk of AKI in critically ill patients.

背景与目的：已知阻塞性睡眠呼吸暂停（obstructive sleep apnea, OSA）是慢性肾脏病（chronic kidney disease, CKD）的危险因素，但目前关于其与急性肾损伤（acute kidney injury, AKI）的关联尚缺乏充分研究记录。本研究旨在探讨重症监护病房（intensive care unit, ICU）环境中，OSA是否与AKI的发病风险相关。方法：本研究筛选了2010年1月1日至2010年12月31日期间入住梅奥诊所ICU的所有连续纳入的明尼苏达州奥姆斯特德县成年居民。于患者入住ICU的前48小时内收集慢性与急性危险因素。采用Logistic回归与倾向得分匹配法，分析OSA与AKI的粗关联及校正后关联。结果：本研究共纳入1259例ICU患者，其中183例在本次ICU入院前已被诊断为OSA。与非OSA患者相比，OSA患者的AKI发生率更高（41% vs. 57%，p < 0.001）。单因素分析显示，CKD、年龄、性别、白种人种族、充血性心力衰竭、脑血管疾病、糖尿病、体质量指数及OSA均与AKI相关。在校正年龄、性别、种族以及慢性与急性危险因素的多因素模型中，OSA仍与AKI存在独立关联（比值比OR=1.53；95%置信区间CI：1.04~2.24；p=0.031）。在176对倾向得分匹配样本中，OSA组与非OSA组的AKI发生率仍存在显著差异（OR=1.54；95%CI：1.01~2.35；p=0.04）。结论：经多导睡眠图（polysomnography）确诊的OSA病史与重症患者的AKI发病风险升高相关。