title: A urine biomarker for severe obstructive sleep apnoea patients: lipocalin-type prostaglandin D synthase.
abstract: Lipocalin-type prostaglandin D synthase (L-PGDS), which is responsible for the biosynthesis of prostaglandin D2, has been reported to have a close connection with cardiovascular disease and sleep regulation. This study aimed to test the hypothesis that the L-PGDS level is a useful marker to identify patients with obstructive sleep apnoea. 64 subjects were enrolled in this prospective study. Urinary concentrations of L-PGDS were measured in the morning. Measurements were made every 4 h in 25 of the 64 patients. Endothelial function was assessed by the reactive hyperaemia peripheral arterial tone index. Circadian variations in L-PGDS concentrations had a significant time-dependent fluctuation (p = 0.0002). L-PGDS was higher in the subjects with severe obstructive sleep apnoea (median 784.7 ng per mg of creatinine, n = 23) than in control subjects (262.1 ng per mg of creatinine, n = 16; p = 0.004) and in those with moderate obstructive sleep apnoea (371.7 ng per mg of creatinine, n = 25; p = 0.0008). After 2 days of continuous positive airway pressure treatment, L-PGDS concentrations in severe obstructive sleep apnoea subjects (n = 12) decreased significantly (p = 0.02) to levels present in control subjects whereas endothelial function did not change significantly. Morning urinary L-PGDS concentrations had significant correlations with the apnoea/hypopnoea index (R2 = 13.9%) and serum high-density lipoprotein cholesterol (R2 = 6.2%), but not with sleepiness. Urinary L-PGDS might be a moderately useful marker to identify patients with severe obstructive sleep apnoea.
authors.affiliation: Graduate School of Medicine, Kyoto University, Kyoto.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Chihara
authors.forename: Kazuo
authors.initials: K
authors.lastname: Chin
authors.forename: Kosuke
authors.initials: K
authors.lastname: Aritake
authors.forename: Yuka
authors.initials: Y
authors.lastname: Harada
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Toyama
authors.forename: Kimihiko
authors.initials: K
authors.lastname: Murase
authors.forename: Chikara
authors.initials: C
authors.lastname: Yoshimura
authors.forename: Takefumi
authors.initials: T
authors.lastname: Hitomi
authors.forename: Toru
authors.initials: T
authors.lastname: Oga
authors.forename: Michiaki
authors.initials: M
authors.lastname: Mishima
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Urade
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000652:urine*; D008076:Cholesterol, HDL / Q000097:blood; D002940:Circadian Rhythm; D045422:Continuous Positive Airway Pressure; D003404:Creatinine / Q000032:analysis; D005260:Female; D006801:Humans; D019746:Intramolecular Oxidoreductases / Q000097:blood* / Q000652:urine*; D054834:Lipocalins / Q000097:blood* / Q000652:urine*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017286:Polysomnography; D011446:Prospective Studies; D012372:ROC Curve; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis* / Q000652:urine*; D055815:Young Adult
chemical_list: D015415:Biomarkers; D008076:Cholesterol, HDL; D054834:Lipocalins; D003404:Creatinine; D019746:Intramolecular Oxidoreductases; C022466:prostaglandin R2 D-isomerase