title: Regular blood donation improves endothelial function in adult males.
abstract: OBJECTIVE
  Endothelial dysfunction, secondary to systemic inflammation and oxidative stress, is known to play a major role in the development and progression of atherosclerosis. It is hypothesized that the lower incidence of coronary artery disease in the premenopausal period in females when compared with males is associated with regular menstrual blood loss. We investigated whether regular blood donation (BD) is associated with improved endothelial function in healthy adult males.
  
  
  METHODS
  Fifty young healthy male volunteers volunteers with a mean age of 30 ± 6 years without overt cardiovascular disease were enrolled to participate in serial consecutive BDs. Serum iron levels as oxidative stress parameters, flow-mediated dilatation (FMD) for endothelial function, 24-h mean diastolic blood pressure for peripheral vascular resistance identification, and high-sensitivity C-reactive protein (hs-CRP) levels as systemic inflammatory markers were evaluated before and after BD. This study used a prospective observational cohort design. Patients with cardiovascular and inflammatory diseases were excluded.
  
  
  RESULTS
  BD was found to improve FMD steadily and significantly when compared with the baseline (mean ± SD: 9.9% ± 3.8%, 10.44% ± 3.9%, 10.65% ± 3.9%, and 10.75 ± 3.9%, respectively, p=0.15, p=0.02, p=0.006 as compared with the baseline). A steady decrease was identified in hs-CRP levels after serial BDs, although this decrease was not statistically significant in the all phases (2.96 ± 3.3 mg/L, 2.26 ± 1.5 mg/L, and 2.12 ± 1.5 mg/L, respectively, p=0.829, p=0.558). The 24-h mean diastolic blood pressures were significantly lower in the chronic phase (77 ± 9 mm Hg, 75 ± 7 mm Hg, and 72 ± 8 mm Hg, respectively, p=0.50, p=0.003), whereas there was no significant change in iron levels in the acute and chronic phases (66 ± 32 mg/dL, 72 ± 43 mg/dL, and 68 ± 33 mg/dL, respectively, p=1.000, p=1.000).
  
  
  CONCLUSIONS
  The results of the study indicate that regular BD improves endothelial function.
authors.affiliation: Department of Cardiology, Faculty of Medicine, Cumhuriyet University; Sivas-Turkey. drhasanyucel@hotmail.com.
authors.forename: Hasan
authors.initials: H
authors.lastname: Yücel
authors.forename: Ali
authors.initials: A
authors.lastname: Zorlu
authors.forename: Hakkı
authors.initials: H
authors.lastname: Kaya
authors.forename: Mehmet Birhan
authors.initials: MB
authors.lastname: Yılmaz
mesh_terms: D000328:Adult; D001782:Blood Donors; D001794:Blood Pressure; D001916:Brachial Artery / Q000502:physiology; D002097:C-Reactive Protein / Q000378:metabolism; D015331:Cohort Studies; D003971:Diastole; D004730:Endothelium, Vascular / Q000502:physiology*; D006801:Humans; D007501:Iron / Q000097:blood; D008297:Male; D011446:Prospective Studies; D011673:Pulsatile Flow
chemical_list: D002097:C-Reactive Protein; D007501:Iron