title: The impact of obstructive sleep apnea on high-sensitivity C-reactive protein in subjects with or without metabolic syndrome.
abstract: BACKGROUND
  It is unclear whether obstructive sleep apnea (OSA) is independently associated with increased levels of the acute-phase reactant C-reactive protein (CRP). The purpose of this study was to evaluate the relationship between OSA and high-sensitivity CRP (hs-CRP) levels according to the presence or absence of metabolic syndrome (MetS).
  
  
  METHODS
  This study recruited 245 male bus drivers from one transportation company in Taiwan. Each participant was evaluated by a polysomnography (PSG) test, blood lipids examination, and hs-CRP. Severity of OSA was categorized according to the apnea-hypopnea index (AHI).
  
  
  RESULTS
  Subjects were categorized into severe OSA group (n = 44; 17.9 %), moderate and mild OSA group (n = 117; 47.8 %), and non-OSA group (n = 84; 34.3 %). AHI had a significant association with hs-CRP (β = 0.125, p = 0.009) adjusting for age, smoking, drinking, and MetS status. Hs-CRP was elevated with severe OSA (β = 0.533, p = 0.005) even adjusting for BMI and MetS. Moreover, there was an independent effect for adjusted odds ratios (AORs) between the stratification of the severity for OSA and MetS.
  
  
  CONCLUSIONS
  Elevated hs-CRP level is associated with severe OSA, independent of known confounders. The effect of OSA in CRP is independent of MetS was identified.
authors.affiliation: Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 35 Keyan Road, Zhunan Town, Miaoli County, 35053, Taiwan, Republic of China.
authors.forename: Wei-Te
authors.initials: WT
authors.lastname: Wu
authors.affiliation: Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Su-Shan
authors.initials: SS
authors.lastname: Tsai
authors.affiliation: Institute of Labor, Occupational Safety and Health, Ministry of Labor, Taipei, Taiwan.|Department of Public Health, China Medical University, Taichung, Taiwan.
authors.forename: Tung-Sheng
authors.initials: TS
authors.lastname: Shih
authors.affiliation: Institute of Labor, Occupational Safety and Health, Ministry of Labor, Taipei, Taiwan.
authors.forename: Ming-Hsiu
authors.initials: MH
authors.lastname: Lin
authors.affiliation: Department of Public Health, China Medical University, Taichung, Taiwan.
authors.forename: Tzu-Chieh
authors.initials: TC
authors.lastname: Chou
authors.affiliation: Department of Physical Medicine and Rehabilitation, Chung Shan Medical University, Taichung, Taiwan.|Center of Sleep Medicine, Chung Shan Medical University Hospital, Taichung, Taiwan.
authors.forename: Hua
authors.initials: H
authors.lastname: Ting
authors.affiliation: Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 35 Keyan Road, Zhunan Town, Miaoli County, 35053, Taiwan, Republic of China.|Department of Nursing, Hungkuang University, Taichung, Taiwan.
authors.forename: Trong-Neng
authors.initials: TN
authors.lastname: Wu
authors.affiliation: Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 35 Keyan Road, Zhunan Town, Miaoli County, 35053, Taiwan, Republic of China. shliou@nhri.org.tw.|Department of Public Health, China Medical University, Taichung, Taiwan. shliou@nhri.org.tw.|Department of Public Health, National Defense Medical Center, Taipei, Taiwan. shliou@nhri.org.tw.
authors.forename: Saou-Hsing
authors.initials: SH
authors.lastname: Liou
mesh_terms: D000328:Adult; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism*; D015331:Cohort Studies; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000145:classification / Q000175:diagnosis* / Q000276:immunology*; D017286:Polysomnography; D012680:Sensitivity and Specificity; D020181:Sleep Apnea, Obstructive / Q000145:classification / Q000175:diagnosis* / Q000276:immunology*; D013223:Statistics as Topic; D013624:Taiwan
chemical_list: D002097:C-Reactive Protein
keywords: Apnea hypopnea; High-sensitivity C-reactive protein; Metabolic syndrome; Obstructive sleep apnea
references.citation: Thorax. 2007 Nov;62(11):969-74
references.pmid: 17557769
references.citation: Am J Respir Crit Care Med. 2005 Sep 1;172(5):625-30
references.pmid: 16120716
references.citation: Thorax. 2007 Jun;62(6):509-14
references.pmid: 17251313
references.citation: Am J Respir Crit Care Med. 2002 Mar 1;165(5):670-6
references.pmid: 11874812
references.citation: Nat Rev Cardiol. 2010 Dec;7(12 ):677-85
references.pmid: 21079639
references.citation: Circulation. 2008 Nov 25;118(22):2243-51, 4p following 2251
references.pmid: 18997194
references.citation: Chest. 2002 Sep;122(3):829-39
references.pmid: 12226021
references.citation: Thorax. 2009 Jan;64(1):67-73
references.pmid: 18786982
references.citation: Am J Respir Crit Care Med. 2002 May 1;165(9):1217-39
references.pmid: 11991871
references.citation: J Hypertens. 1997 Dec;15(12 Pt 2):1593-603
references.pmid: 9488210
references.citation: N Engl J Med. 2000 May 11;342(19):1378-84
references.pmid: 10805822
references.citation: J Appl Physiol (1985). 2003 Jan;94(1):179-84
references.pmid: 12391099
references.citation: JAMA. 2000 Apr 12;283(14):1829-36
references.pmid: 10770144
references.citation: Prev Med. 2003 Sep;37(3):233-41
references.pmid: 12914829
references.citation: Hypertension. 2001 Feb;37(2 Pt 2):511-5
references.pmid: 11230327
references.citation: Proc Am Thorac Soc. 2008 Feb 15;5(2):207-17
references.pmid: 18250214
references.citation: Chest. 2009 Apr;135(4):950-956
references.pmid: 19225064
references.citation: Am J Respir Crit Care Med. 2002 Mar 1;165(5):677-82
references.pmid: 11874813
references.citation: Eur Respir J. 2000 Jul;16(1):128-33
references.pmid: 10933098
references.citation: Circulation. 2002 May 28;105(21):2462-4
references.pmid: 12034649
references.citation: Sleep. 2009 Feb;32(2):150-7
references.pmid: 19238801
references.citation: Am J Respir Crit Care Med. 2007 Oct 1;176(7):706-12
references.pmid: 17556718
references.citation: Eur Respir J. 2009 May;33(5):1195-205
references.pmid: 19407053
references.citation: Am J Clin Nutr. 2004 Jan;79(1):31-9
references.pmid: 14684394
references.citation: Am J Med. 1999 May;106(5):506-12
references.pmid: 10335721
references.citation: Circulation. 2003 Mar 4;107(8):1129-34
references.pmid: 12615790
references.citation: Sleep Med Rev. 2000 Oct;4(5):411-33
references.pmid: 17210275
references.citation: Proc Am Thorac Soc. 2008 Feb 15;5(2):136-43
references.pmid: 18250205
references.citation: Sleep. 2007 Aug;30(8):991-6
references.pmid: 17702268