title: Effect of continuous positive airway pressure on serum cystatin C among obstructive sleep apnea syndrome patients.
abstract: OBJECTIVE
  The purpose of the present study was to evaluate the influence of continuous positive airway pressure (CPAP) on serum cystatin C, a novel biomarker of early renal impairment, among obstructive sleep apnea (OSA) patients.
  
  
  METHODS
  Newly diagnosed severe OSA patients who treated with CPAP for 3 months were enrolled from two sleep laboratories. Serum biomarkers of renal impairment, cystatin C, creatinine and estimated glomerular filtration rate (eGFR), were detected before and after CPAP treatment.
  
  
  RESULTS
  A total of 39 severe OSA patients were enrolled, 29 (74.4 %) were male, and mean age was 51.2 ± 12.2 years. After CPAP treatment, there were no changes of creatinine and eGFR (77.80 ± 20.00 vs. 75.3 ± 16.60 and 98.69 ± 31.74 vs. 100.20 ± 28.30, all p > 0.05), but cystatin C declined significantly (0.87 ± 0.18 vs. 0.77 ± 0.21, p = 0.000).
  
  
  CONCLUSIONS
  CPAP can decrease cystatin C levels among severe OSA patients and may prevent the latent renal impairment.
authors.affiliation: Department of Respiratory Medicine, Zhongshan Hospital, Xiamen University, No. 201, Hubin Nan Road, Siming District, Xiamen, 361004, Fujian, People's Republic of China, zhangxiaobincn@126.com.
authors.forename: Xiao-Bin
authors.initials: XB
authors.lastname: Zhang
authors.forename: Xing-Tang
authors.initials: XT
authors.lastname: Jiang
authors.forename: Qi-Chang
authors.initials: QC
authors.lastname: Lin
authors.forename: Xiao
authors.initials: X
authors.lastname: Chen
authors.forename: Hui-Qing
authors.initials: HQ
authors.lastname: Zeng
mesh_terms: D000886:Anthropometry; D015415:Biomarkers / Q000097:blood; D045422:Continuous Positive Airway Pressure; D003404:Creatinine / Q000097:blood; D055316:Cystatin C / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography; D020181:Sleep Apnea, Obstructive / Q000097:blood* / Q000503:physiopathology / Q000628:therapy*; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D055316:Cystatin C; D003404:Creatinine