title: Red cell distribution width and uric acid in patients with obstructive sleep apnea.
abstract: BACKGROUND
  Obstructive sleep apnea (OSA), characterized by recurrent partial or complete pharyngeal closure, resulting in apnea or hypopnea, is closely associated with cardiovascular disorders (CVDs). Elevated red cell distribution width (RDW) and serum uric acid (SUA) levels have also been associated with CVDs and the consequent mortality. The aim of this study is to determine SUA levels and RDW in patients with OSA which is major a risk factor for CVDs.
  
  
  METHODS
  This was a retrospective study involving 600 subjects evaluated by polysomnography. Patients were grouped according to the apnea-hypopnea index (AHI), expressed as control group or as mild OSA, moderate OSA, and severe OSA groups.
  
  
  RESULTS
  The mean RDW and the mean SUA were significantly higher in the severe OSA group than in all other groups (P < .015 and P < .003, respectively, for all). RDW was negatively correlated with minimum SpO2(r = -.142, P < .01) and positively correlated with mean oxygen desaturation time (r = .113, P < .05). SUA was negatively correlated with minimum SpO2(r = -.229, P < .01). The RDW was significantly higher in the OSA patients with CVDs than in those with OSA only (P < .05), although there was no significant difference between the OSA patients with and without CVDs in terms of the SUA in any of the groups (P > .05).
  
  
  CONCLUSIONS
  Elevated levels of SUA and RDW were associated with OSA severity, as defined by AHI. In addition, RDW was significantly higher in severe OSA with CVDs.
authors.affiliation: Department of Chest Diseases, School of Medicine, Yuzuncu Yil University, Van, Turkey.
authors.forename: Aysel
authors.identifier: http://orcid.org/0000-0003-4946-6250
authors.initials: A
authors.lastname: Sunnetcioglu
authors.affiliation: Department of Chest Diseases, School of Medicine, Yuzuncu Yil University, Van, Turkey.
authors.forename: Hulya
authors.initials: H
authors.lastname: Gunbatar
authors.affiliation: Department of Chest Diseases, School of Medicine, Yuzuncu Yil University, Van, Turkey.
authors.forename: Hanifi
authors.initials: H
authors.lastname: Yıldız
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D002318:Cardiovascular Diseases / Q000097:blood* / Q000453:epidemiology / Q000209:etiology; D004909:Erythrocyte Indices; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000097:blood / Q000150:complications*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D017286:Polysomnography / Q000379:methods; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000097:blood* / Q000150:complications / Q000175:diagnosis; D014421:Turkey / Q000453:epidemiology; D014527:Uric Acid / Q000097:blood*; D055815:Young Adult
chemical_list: D015415:Biomarkers; D014527:Uric Acid
keywords: cardiovascular disorders; obstructive sleep apnea; red cell distribution width; uric acid