Resting Brain Perfusion and Selected Vascular Risk Factors in Healthy Elderly Subjects

TY - JOUR

T1 - Resting Brain Perfusion and Selected Vascular Risk Factors in Healthy Elderly Subjects

AU - Henriksen, Otto M.

AU - Jensen, Lars T

AU - Krabbe, Katja

AU - Guldberg, Per

AU - Teerlink, Tom

AU - Rostrup, Egill

PY - 2014/5/19

Y1 - 2014/5/19

N2 - BACKGROUND AND PURPOSE: Both cerebral hypoperfusion and vascular risk factors have been implicated in early aging of the brain and the development of neurodegenerative disease. However, the current knowledge of the importance of cardiovascular health on resting brain perfusion is limited. The aim of the present study was to elucidate the relation between brain perfusion variability and risk factors of endothelial dysfunction and atherosclerosis in healthy aged subjects.METHODS: Thirty-eight healthy subjects aged 50-75 years old were included. Mean global brain perfusion was measured using magnetic resonance phase contrast mapping and regional brain perfusion by use of arterial spin labeling.RESULTS: Mean global brain perfusion was inversely correlated with caffeine and hematocrit, and positively with end-tidal PCO2. Furthermore, the mean global brain perfusion was inversely correlated with circulating homocysteine, but not with asymmetric dimethylarginine, dyslipidemia or the carotid intima-media thickness. The relative regional brain perfusion was associated with circulating homocysteine, with a relative parietal hypoperfusion and a frontal hyperperfusion. No effect on regional brain perfusion was observed for any of the other risk factors. A multiple regression model including homocysteine, caffeine, hematocrit and end-tidal PCO2, explained nearly half of the observed variability.CONCLUSION: Both intrinsic and extrinsic factors influenced global cerebral perfusion variation between subjects. Further, the results suggest that the inverse relation between homocysteine and brain perfusion is owing to other mechanisms, than reflected by asymmetric dimethylarginine, and that homocysteine may be a marker of cerebral perfusion in aging brains.

AB - BACKGROUND AND PURPOSE: Both cerebral hypoperfusion and vascular risk factors have been implicated in early aging of the brain and the development of neurodegenerative disease. However, the current knowledge of the importance of cardiovascular health on resting brain perfusion is limited. The aim of the present study was to elucidate the relation between brain perfusion variability and risk factors of endothelial dysfunction and atherosclerosis in healthy aged subjects.METHODS: Thirty-eight healthy subjects aged 50-75 years old were included. Mean global brain perfusion was measured using magnetic resonance phase contrast mapping and regional brain perfusion by use of arterial spin labeling.RESULTS: Mean global brain perfusion was inversely correlated with caffeine and hematocrit, and positively with end-tidal PCO2. Furthermore, the mean global brain perfusion was inversely correlated with circulating homocysteine, but not with asymmetric dimethylarginine, dyslipidemia or the carotid intima-media thickness. The relative regional brain perfusion was associated with circulating homocysteine, with a relative parietal hypoperfusion and a frontal hyperperfusion. No effect on regional brain perfusion was observed for any of the other risk factors. A multiple regression model including homocysteine, caffeine, hematocrit and end-tidal PCO2, explained nearly half of the observed variability.CONCLUSION: Both intrinsic and extrinsic factors influenced global cerebral perfusion variation between subjects. Further, the results suggest that the inverse relation between homocysteine and brain perfusion is owing to other mechanisms, than reflected by asymmetric dimethylarginine, and that homocysteine may be a marker of cerebral perfusion in aging brains.

KW - Aged

KW - Arginine

KW - Brain

KW - Caffeine

KW - Cerebrovascular Circulation

KW - Female

KW - Hematocrit

KW - Homocysteine

KW - Humans

KW - Male

KW - Middle Aged

KW - Risk Factors

KW - Journal Article

KW - Research Support, Non-U.S. Gov't

U2 - 10.1371/journal.pone.0097363

DO - 10.1371/journal.pone.0097363

M3 - Journal article

C2 - 24840730

SN - 1932-6203

VL - 9

JO - PLoS Computational Biology

JF - PLoS Computational Biology

IS - 5

M1 - e97363

ER -