Intrusion errors moderate the relationship between blood glucose and regional cerebral blood flow in cognitively unimpaired older adults

AbstractRegional cerebral blood flow (CBF) has a complex relationship with cognitive functioning such that cognitively unimpaired individuals at risk for Alzheimer’s disease (AD) may show regional hyperperfusion, while those with cognitive impairment typically show hypoperfusion. Diabetes and word-list intrusion errors are both linked to greater risk of cognitive decline and dementia. Our study examined associations between fasting blood glucose, word-list intrusion errors, and regional CBF. 113 cognitively unimpaired older adults had arterial spin labeling MRI to measure CBF in a priori AD vulnerable regions: medial temporal lobe (MTL), inferior parietal lobe (IPL), precuneus, medial orbitofrontal cortex (mOFC), and pericalcarine (control region). Hierarchical linear regressions, adjusting for demographics, vascular risk, and reference CBF region, examined the main effect of blood glucose on regional CBF as well as whether intrusions moderated this relationship. Higher glucose was associated with higher CBF in the precuneus (β = .134, 95% CI = .007 to .261, p = .039), IPL (β = .173, 95% CI = .072 to .276, p = .001), and mOFC (β = .182, 95% CI = .047 to .320, p = .009). There was no main effect of intrusions on CBF across regions. However, the glucose x intrusions interaction was significant such that having higher glucose levels and more intrusion errors was associated with reduced CBF in the MTL (β = -.186, 95% CI = -.334 to -.040, p = .013) and precuneus (β = -.146, 95% CI = -.273 to -.022, p = .022). These findings may reflect early neurovascular dysregulation, whereby higher CBF is needed to maintain unimpaired cognition in individuals with higher glucose levels. However, lower regional CBF in unimpaired participants with both higher glucose and more intrusions suggests a failure in this early compensatory mechanism that may signal a decrease in neural activity in AD vulnerable regions.

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Intima-Media Thickness and Regional Cerebral Blood Flow in Older Adults

Stroke ◽

10.1161/strokeaha.109.566810 ◽

2010 ◽

Vol 41 (2) ◽

pp. 273-279 ◽

Cited By ~ 25

Author(s):

Jitka Sojkova ◽

Samer S. Najjar ◽

Lori L. Beason-Held ◽

E. Jeffrey Metter ◽

Christos Davatzikos ◽

...

Keyword(s):

Older Adults ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Regional Cerebral Blood Flow ◽

Intima Media Thickness ◽

Regional Cerebral Blood ◽

Media Thickness

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IC-P-117: Characterization of regional cerebral blood flow in mild cognitive impairment and older adults with cognitive complaints

Alzheimer s & Dementia ◽

10.1016/j.jalz.2013.05.114 ◽

2013 ◽

Vol 9 ◽

pp. P71-P71 ◽

Cited By ~ 1

Author(s):

Yang Wang ◽

John West ◽

Shannon Risacher ◽

Brenna McDonald ◽

Eileen Tallman ◽

...

Keyword(s):

Older Adults ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Regional Cerebral Blood Flow ◽

Regional Cerebral Blood ◽

Cognitive Complaints

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Aging and Recognition Memory: Changes in Regional Cerebral Blood Flow Associated with Components of Reaction Time Distributions

Journal of Cognitive Neuroscience ◽

10.1162/089892999563571 ◽

1999 ◽

Vol 11 (5) ◽

pp. 511-520 ◽

Cited By ~ 50

Author(s):

David J. Madden ◽

Lawrence R. Gottlob ◽

Laura L. Denny ◽

Timothy G. Turkington ◽

James M. Provenzale ◽

...

Keyword(s):

Older Adults ◽

Blood Flow ◽

Young Adults ◽

Cerebral Blood Flow ◽

Reaction Time ◽

Task Performance ◽

Regional Cerebral Blood Flow ◽

Regional Cerebral Blood ◽

Age Related ◽

The Mean

We used H215O positron emission tomography (PET) to measure age-related changes in regional cerebral blood flow (rCBF) during a verbal recognition memory task. Twelve young adults (20 to 29 years) and 12 older adults (62 to 79 years) participated. Separate PET scans were conducted during Encoding, Baseline, and Retrieval conditions. Each of the conditions involved viewing a series of 64 words and making a two-choice response manually. The complete reaction time (RT) distributions in each task condition were characterized in terms of an ex-Gaussian model (convolution of exponential and Gaussian functions). Parameter estimates were obtained for the mean of the exponential component (τ), representing a task-specific decision process and the mean of the Gaussian component (μ), representing residual sensory coding and response processes. Independently of age group, both μ and τ were higher in the Encoding and Retrieval conditions than in the Baseline condition, and τ was higher during Retrieval than during Encoding. Age-related slowing in task performance was evident primarily in μ. For young adults, rCBF activation in the right prefrontal cortex, in the Retrieval condition, was correlated positively with μ but not with τ. For older adults, rCBF changes (both increases and decreases) in several cortical regions were correlated with both μ and τ. The data suggest that the attentional demands of this task are relatively greater for older adults and consequently lead to the recruitment of additional neural systems during task performance.

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Regional cerebral blood flow and glucose utilization during hypoglycemia in newborn dogs

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1989.256.6.h1659 ◽

1989 ◽

Vol 256 (6) ◽

pp. H1659-H1666

Author(s):

D. J. Mujsce ◽

M. A. Christensen ◽

R. C. Vannucci

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Blood Glucose ◽

White Matter ◽

Regional Cerebral Blood Flow ◽

Glucose Utilization ◽

Regional Cerebral Blood ◽

Acid Base Balance ◽

Arterial Blood ◽

Arterial Po2

To assess alterations in regional cerebral blood flow and glucose utilization during perinatal hypoglycemia, newborn dogs (2-7 days postnatal age) were anesthetized with halothane, tracheostomized, paralyzed, and artificially ventilated with 70% N2O-30% O2 to maintain arterial normoxia and normocapnia (arterial PO2 greater than 60 mmHg; arterial PCO2: 35-42 mmHg; arterial pH: 7.35-7.45). Regional cerebral blood flow (rCBF) and glucose utilization (rCGU) were determined with iodo-[14C]antipyrine and 2-deoxy-[14C]glucose as the radioactive tracers, respectively. Hypoglycemia with blood glucose concentrations averaging 0.9 mmol/l was achieved within 90-120 min in 10 animals using intermittent intravenous injections of regular insulin; 10 control animals received 0.9% saline (blood glucose = 9 mmol/l). During hypoglycemia, mean arterial blood pressure was 81% of control, whereas heart rate was unchanged. Arterial O2 and acid-base balance were well maintained (arterial PO2 = 68 mmHg; PCO2 = 37 mmHg; pH = 7.35). Hypoglycemia was associated with significant increases in rCBF in all of 16 analyzed structures, ranging from 172% (parietal white matter) to 249% (thalamus) of control values (17-65 ml.100 g-1.min-1). During hypoglycemia, rCGU was relatively unchanged from normoglycemic values in 11 of 16 brain structures. Significant reductions in rCGU were seen only in occipital white matter (-31%) and in the cerebellar vermis and hemisphere (-31 and -43%, respectively). CGU actually increased slightly in the pons and medulla (+12 and +19%, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

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Reduced Regional Cerebral Blood Flow Relates to Poorer Cognition in Older Adults With Type 2 Diabetes

Frontiers in Aging Neuroscience ◽

10.3389/fnagi.2018.00270 ◽

2018 ◽

Vol 10 ◽

Cited By ~ 24

Author(s):

Katherine J. Bangen ◽

Madeleine L. Werhane ◽

Alexandra J. Weigand ◽

Emily C. Edmonds ◽

Lisa Delano-Wood ◽

...

Keyword(s):

Type 2 Diabetes ◽

Older Adults ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Regional Cerebral Blood Flow ◽

Regional Cerebral Blood

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Activation of Regional Cerebral Blood Flow by a Memorization Task in Early Parkinson's Disease Patients and Normal Subjects

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.1994.54 ◽

1994 ◽

Vol 14 (3) ◽

pp. 431-438 ◽

Cited By ~ 10

Author(s):

J.-F. Démonet ◽

P. Celsis ◽

A. Agniel ◽

D. Cardebat ◽

O. Rascol ◽

...

Keyword(s):

Parkinson’S Disease ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Free Recall ◽

Regional Cerebral Blood Flow ◽

Word List ◽

Normal Subjects ◽

Regional Cerebral Blood ◽

Passive Listening ◽

Early Parkinson’S Disease

Task-induced changes in regional cerebral blood flow (rCBF) during memory activation were compared in 18 right-handed patients with early Parkinson's disease (PD) and 20 normal volunteers using the same activation paradigm. We used single-photon emission computed tomography and 133Xe in 21 regions of interest during rest, passive listening of a word list, and memorization of another word list, which was followed by a free recall test immediately after completion of the rCBF measurement. The average performance on free recall was not significantly lower in PD patients than in controls. In normal subjects, five left-sided regions (anterior middle frontal, posterior inferior frontal, superior middle temporal, thalamic, and lenticular) showed a significant increase in memorizing compared to passive listening. This pattern of activation suggests the existence of a verbal rehearsal strategy during the memorization task in normals. In PD patients, increases in these regions did not reach significance, whereas significant activations were noted in superior prefrontal regions. Such alterations in the pattern of activation in PD patients, despite a memory performance similar to that of controls are viewed as a consequence of an early dysfunction of the articulatory loop system and of compensatory mechanisms in other parts of the frontal lobe emerging in the early stages of the disease.

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