Elevated global cerebral blood flow, oxygen extraction fraction and unchanged metabolic rate of oxygen in young adults with end-stage renal disease: an MRI study.
OBJECTIVE
To noninvasively assess global cerebral blood flow (CBF), oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO2) in young adults with end-stage renal disease (ESRD).


METHODS
Thirty-six patients and 38 healthy volunteers were included and took part in MR examinations, blood and neuropsychological tests. CBF and OEF were measured by phase-contrast and T2-relaxation-under-spin-tagging MRI techniques, respectively. CMRO2 was computed from CBF, OEF and hematocrit according to Fick's principle. Correlations were performed between MR measurements, blood biochemistry measurements and neuropsychological test scores.


RESULTS
Compared with controls, ESRD patients had elevated CBF (72.9 ± 12.5 vs. 63.8 ± 8.5 ml min(-1) 100 g(-1), P < 0.001), elevated OEF (47.2 ± 10.2 vs. 35.8 ± 5.4 %, P < 0.001), but unaffected CMRO2 (199.5 ± 36.4 vs. 193.8 ± 28.6 μmol O2 min(-1) 100 g(-1), P = 0.879). Hematocrit negatively correlated with CBF (r = -0.640, P < 0.001) and OEF (r = -0.701, P < 0.001), but not with CMRO2. Altered neuropsychological test scores of ESRD patients were associated with OEF and CBF, but not with CMRO2. There were weak relationships between eGFR and hematocrit (r = 0.308, P = 0.068) or CBF (r = 0.318, P = 0.059).


CONCLUSIONS
Our findings suggested that anaemic young adults with ESRD may afford higher CBF and OEF to maintain a normal CMRO2. Despite this compensatory process, however, cognitive function was still impaired and its severity was correlated with their CBF and OEF abnormality.


CONCLUSIONS
• Anaemic young adults with ESRD may afford higher CBF and OEF. • Anaemic young adults with ESRD maintain a normal CMRO 2 . • Cognitive function was still impaired in young ESRD adults. • The severity of cognitive dysfunction correlated with CBF and OEF changes.
Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China.|College of Aivil Aviation, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu, 210016, China.
Gang
G
Zheng
National Clinical Research Center of Kidney Diseases, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China.
Jiqiu
J
Wen
Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA.
Hanzhang
H
Lu
Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China.|College of Aivil Aviation, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu, 210016, China.
Yaxian
Y
Lou
Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China.|College of Aivil Aviation, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu, 210016, China.
Zhiying
Z
Pan
Siemens Shenzhen Magnetic Resonance Ltd., Shenzhen, Guangdong, China.
Wei
W
Liu
Siemens MR NEA Collaboration, Siemens Ltd., Shanghai, China.
Hui
H
Liu
National Clinical Research Center of Kidney Diseases, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China.
Xue
X
Li
National Clinical Research Center of Kidney Diseases, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China.
Zhe
Z
Zhang
Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China.
Huijuan
H
Chen
Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China.
Xiang
X
Kong
Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China.
Song
S
Luo
Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China.
Xiaolu
X
Jiang
Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China.|College of Aivil Aviation, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu, 210016, China.
Ya
Y
Liu
Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China.
Zongjun
Z
Zhang
Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China. kevinzhlj@163.com.
Long Jiang
LJ
Zhang
Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China. cjr.luguangming@vip.163.com.
Guang Ming
GM
Lu
D000293:Adolescent; D000328:Adult; D001921:Brain / Q000098:blood supply*; D002560:Cerebrovascular Circulation / Q000502:physiology; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000378:metabolism / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D010100:Oxygen / Q000097:blood*; D010101:Oxygen Consumption / Q000502:physiology; D055815:Young Adult
D010100:Oxygen
Cerebral blood flow; Cerebral metabolic rate of oxygen; End-stage renal disease; Oxygen extract fraction; Uremic encephalopathy