Associations between Markers of Glucose and Insulin Function and Cognitive Function in Healthy African American Elders

Components of metabolic syndrome associated with lower neurocognitive performance in youth with perinatally acquired HIV and youth who are HIV-exposed uninfected

We investigated the association of metabolic syndrome (MetS) and its components [abdominal obesity, elevated triglycerides (TG), low HDL cholesterol, elevated blood pressure (BP), and impaired fasting glycemia (IFG)] with neurocognitive impairment in youth with perinatally acquired HIV (YPHIV) or who are perinatally HIV-exposed uninfected (YPHEU). This was an observational study with a comparison group of 350 YPHIV and 68 YPHEU ages 10-19 years. Youth with MetS components measured between 1 year before and 3 months after a baseline neurocognitive assessment (Wechsler Intelligence Scale) were selected from the Pediatric HIV/AIDS Cohort Study (PHACS). A sub-group completed another assessment 3 years later. We assessed the association of each baseline MetS component with five standardized neurocognitive indices at baseline and changes in indices over time. At baseline, 15% of YPHIV and 18% of YPHEU met criteria for ≥ 2 MetS components. Among YPHIV, there was no association between MetS components and neurocognitive indices at baseline; however, over time, elevated baseline BP was associated with a greater decrease in mean Perceptual Reasoning scores (-4.3;95%CI: -8.8,0.3) and ≥ 2 MetS components with a greater decrease in mean Processing Speed scores (-5.1;95%CI: -9.4, -0.8). Among YPHEU, elevated TG was associated with lower mean Verbal Comprehension, Perceptual Reasoning, and Full-scale IQ scores at baseline, and IFG with lower mean Verbal Comprehension scores. Components of MetS in YPHIV (elevated BP) and YPHEU (elevated TG and IFG) were associated with lower neurocognitive performance index scores. Studies to elucidate how modifying metabolic risk factors early in life may improve neurocognitive outcomes in this population are warranted.

Elevated Fasting Plasma Glucose Is Associated With an Increased Risk of MCI: A Community-Based Cross-Sectional Study

BACKGROUND

Mild cognitive impairment (MCI) is a transitional state between normal elderly people and dementia, with a higher risk of dementia transition. The primary purpose of the current study was to investigate whether routine blood and blood biochemical markers could be used to predict the onset of MCI.

METHODS

Data was obtained from the cohort study on brain health of the elderly in Shanghai. A total of 1015 community elders were included in the current study. Based on clinical evaluation and the scores of Montreal Cognitive Assessment (MoCA), these participants were divided into the MCI (n=444) and cognitively normal groups (n=571). Then we tested their fasting blood routine and blood biochemical indexes, and collected their general demographic data by using a standard questionnaire.

RESULTS

By using binary logistic regression analysis and the ROC curve, we found that elevated fasting plasma glucose (p=0.025, OR=1.118, OR=1.014-1.233) was a risk factor for MCI.

CONCLUSIONS

Elevated fasting blood glucose may be a risk factor for mild cognitive impairment, but the above conclusions need to be verified by longitudinal studies.

Type 2 diabetes and cognitive dysfunction in minorities: a review of the literature

OBJECTIVES

The purpose of this review was to summarize the current status of knowledge regarding cognitive dysfunction and diabetes in minorities. Literature on the interaction of cognitive dysfunction and diabetes was analyzed to (a) examine the number and characteristics of studies in minority populations; (b) identify tests used to assess cognitive function in diabetes; (c) consider the impact of diabetes on cognitive function; and (d) assess the moderators of the association between diabetes and cognitive function.

DESIGN

A literature review and thematic analysis was conducted. Studies were mapped to describe their design, target population, instruments used, and the physiologic, psychosocial, and socioeconomic findings related to cognitive function and diabetes. Twelve studies met the inclusion criteria.

RESULTS

Hispanics were studied more than any other ethnic group. Rates and degree of cognitive dysfunction were more prevalent in minorities than non-Hispanic whites. Overall, 28 different tests were administered to evaluate cognitive function. There was some variation among findings regarding the relationship of cognitive function and diabetes. Risk for cognitive decline was associated with the diagnosis of diabetes alone, regardless of whether the diabetes was treated or untreated. Higher rates of discrimination were associated with greater cognitive decline Conclusion: Given the context of minority health, there is a potential for higher negative health impact due to the increased prevalence of diabetes and cognitive dysfunction and other related health disparities. Reduction of physiological risk factors for diabetes, consistency in assessment, as well as elimination of structural barriers such as access to care should be helpful in decreasing the incidence of both diabetes and cognitive decline. More research is needed to determine whether the observed differences are modifiable and to identify factors involved in the interaction of diabetes and cognitive decline-not only physiological factors, but factors related to socioeconomic status and quality of life.

Impaired fasting blood glucose is associated to cognitive impairment and cerebral atrophy in middle-aged non-human primates

Age-associated cognitive impairment is a major health and social issue because of increasing aged population. Cognitive decline is not homogeneous in humans and the determinants leading to differences between subjects are not fully understood. In middle-aged healthy humans, fasting blood glucose levels in the upper normal range are associated with memory impairment and cerebral atrophy. Due to a close evolutional similarity to Man, non-human primates may be useful to investigate the relationships between glucose homeostasis, cognitive deficits and structural brain alterations. In the grey mouse lemur, Microcebus murinus, spatial memory deficits have been associated with age and cerebral atrophy but the origin of these alterations have not been clearly identified. Herein, we showed that, on 28 female grey mouse lemurs (age range 2.4-6.1 years-old), age correlated with impaired fasting blood glucose (r_s=0.37) but not with impaired glucose tolerance or insulin resistance. In middle-aged animals (4.1-6.1 years-old), fasting blood glucose was inversely and closely linked with spatial memory performance (r_s=0.56) and hippocampus (r_s=−0.62) or septum (r_s=−0.55) volumes. These findings corroborate observations in humans and further support the grey mouse lemur as a natural model to unravel mechanisms which link impaired glucose homeostasis, brain atrophy and cognitive processes.