Assessment of ultrasound flow-mediated dilation of brachial artery in regular blood donors in a Nigerian Tertiary Hospital

ABSTRACT

Background: Iron is a pro-oxidant cofactor that may be linked to cardiovascular disease (CVD) progression and reduction of body iron stores have been hypothesized to reduce the risk of CV disease. Aim: The aim of this study is to assess reduction in CVD risk susceptibility among regular blood donors compared with nondonors using ultrasound brachial artery flow-mediated dilation (BAFMD). Settings and Design: A prospective comparative study designed to establish the difference between mean flow-mediated dilatation (FMD) in the patients who are regular blood donors compared with nondonors recruited from a Teaching Hospital donor clinic. Materials and Methods: Data were collected over 7 months from December 2014 to June 2015. 100 eligible regular male blood donors, aged 21­50 years, were selected from a Teaching Hospital blood donor records and their BAFMD assessed. 50 nondonors/ first time donors, of equivalent age group, consecutively were assessed for comparison. Serum markers of iron stores, markers of oxidative stress and other related cardiac risk factors were also assessed in all patients. Results: BAFMD was significantly greater in regular blood donors when compared with nondonors (13.95% ± 7.02% vs. 8.20% ± 4.19%, P = 0.000). Serum ferritin was significantly decreased in regular blood donors when compared with nondonors (mean value 41.92 ng/ml ± 23.12 ng/ml vs. 61.97 ± 30.19 ng/ml, P = 0.000), but Hb did not differ between the groups. High FMD was significantly associated with high C-high-density lipoprotein and low C-LDL (r = −0.215*, P = 0.032, r = 0.188, P = 0.031, r = 0.193, P = 0.027, r = 0.0279, P = 0.002, r = 0.139, P = 0.084). LDL was decreased in regular blood donors compared with nondonors. Conclusion: The study provides prognostic information for assessing ultrasound BAFMD as a cardiac risk marker. Regular blood donors have enhanced cardiovascular function with increased flow-mediated dilation, decreased body iron stores, and decreased oxidative stress compared with nondonors