TY - JOUR
T1 - The effects of healthy aging on cerebral hemodynamic responses to posture change
AU - Edlow, Brian L.
AU - Kim, Meeri N.
AU - Durduran, Turgut
AU - Zhou, Chao
AU - Putt, Mary E.
AU - Yodh, Arjun G.
AU - Greenberg, Joel H.
AU - Detre, John A.
PY - 2010
Y1 - 2010
N2 - Aging is associated with an increased incidence of orthostatic hypotension, impairment of the baroreceptor reflex and lower baseline cerebral blood flow. The effect of aging on cerebrovascular autoregulation, however, remains to be fully elucidated. We used a novel optical instrument to assess microvascular cerebral hemodynamics in the frontal lobe cortex of 60 healthy subjects ranging from ages 20-78. Diffuse correlation spectroscopy (DCS) and near-infrared spectroscopy (NIRS) were used to measure relative cerebral blood flow (rCBF), total hemoglobin concentration (THC), oxyhemoglobin concentration (HbO 2) and deoxyhemoglobin concentration (Hb). Cerebral hemodynamics were monitored for 5 min at each of the following postures: head-of-bed 30°, supine, standing and supine. Supine-to-standing posture change caused significant declines in rCBF, THC and HbO2, and an increase in Hb, across the age continuum (p < 0.01). Healthy aging did not alter postural changes in frontal cortical rCBF (p = 0.23) and was associated with a smaller magnitude of decline in HbO2 (p < 0.05) during supine-to-standing posture change. We conclude that healthy aging does not alter postural changes in frontal cortical perfusion.
AB - Aging is associated with an increased incidence of orthostatic hypotension, impairment of the baroreceptor reflex and lower baseline cerebral blood flow. The effect of aging on cerebrovascular autoregulation, however, remains to be fully elucidated. We used a novel optical instrument to assess microvascular cerebral hemodynamics in the frontal lobe cortex of 60 healthy subjects ranging from ages 20-78. Diffuse correlation spectroscopy (DCS) and near-infrared spectroscopy (NIRS) were used to measure relative cerebral blood flow (rCBF), total hemoglobin concentration (THC), oxyhemoglobin concentration (HbO 2) and deoxyhemoglobin concentration (Hb). Cerebral hemodynamics were monitored for 5 min at each of the following postures: head-of-bed 30°, supine, standing and supine. Supine-to-standing posture change caused significant declines in rCBF, THC and HbO2, and an increase in Hb, across the age continuum (p < 0.01). Healthy aging did not alter postural changes in frontal cortical rCBF (p = 0.23) and was associated with a smaller magnitude of decline in HbO2 (p < 0.05) during supine-to-standing posture change. We conclude that healthy aging does not alter postural changes in frontal cortical perfusion.
KW - Aging
KW - Autoregulation
KW - Cerebral blood flow
KW - Diffuse correlation spectroscopy
KW - Near-infrared spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=77949840586&partnerID=8YFLogxK
U2 - 10.1088/0967-3334/31/4/002
DO - 10.1088/0967-3334/31/4/002
M3 - Article
AN - SCOPUS:77949840586
SN - 0967-3334
VL - 31
SP - 477
EP - 495
JO - Physiological Measurement
JF - Physiological Measurement
IS - 4
ER -