The Metabolic Syndrome, Inflammation, and Risk of Cognitive Decline

Abstract

ARDIOVASCULAR AND METAbolic risk factors such as hypertension and diabetes have been hypothesized to play a role in the pathogenesis of Alzheimer disease (AD) as well as in development of vascular dementia. [1][2][3][4] The metabolic syndrome, 5 a clustering of several commonly occurring disorders that include (1) abdominal obesity, (2) hypertriglyceridemia, (3) low highdensity lipoprotein (HDL) level, (4) hypertension, and (5) hyperglycemia, has not been specifically investigated as a risk factor for cognitive decline in elderly individuals. The metabolic syndrome may be a risk factor for cognitive decline because it summarizes the joint effects of these risk factors. As obesity and sedentary lifestyle rise in the United States, identification and explication of the role of these modifiable behaviors in increasing risk for developing deleterious outcomes such as cognitive impairment is critical. If the metabolic syndrome is associated with increased risk of developing cognitive impairment, then early identification and treatment of these individuals might offer avenues for disease course modification.High levels of inflammation increase the risk of the development of diabetes and atherosclerosis and are thought to be a possible mechanism for the adverse consequences of the metabolic syndrome. 6,7 Indeed, level of inflammation in the setting of the meta-bolic syndrome may help identify those at especially high risk for adverse outcomes. Furthermore, subclinical inflammation might be an underlying factor for an association between the

O3‐06‐06: The Projected impact of risk factor reduction on Alzheimer's disease prevalence

“…90 Diabetes could also impact cognition through its affects on blood glucose levels, insulin resistance, inflammation or alterations in beta-amyloid metabolism. [91][92][93] …”

Metabolic Syndrome Predicts Cognitive Decline in Community-Dwelling Elderly People: A 10-Year Cohort Study

“…Hyperglycemia, a marker for insulin resistance and the main feature of MetS, may have direct negative effects on cognition, whereas such direct effects have not been discovered for the other components [23]. Another probable mechanism is the effect of the elevated inflammation often seen in patients with MetS [7,23] Markers of inflammation have been associated with an increased risk of cognitive decline and developing dementia [7]. Inflammation may also be viewed as part of MetS.…”

“…MetS is known to affect cognition, regardless of the mechanism, and evidence suggests that MetS, as a whole, is associated with declining cognitive function [4]. Although several studies have investigated the association between MetS and the risk of cognitive decline [5][6][7][8] in recent years, the effect of MetS on the rate of cognitive decline remains controversial [4,5].…”

Relation of insulin resistance to neurocognitive function and electroencephalography in obese children

“…However, we observed an association between cognitive impairment and IR even though children with OSA symptoms were excluded from the study. Previous reports have revealed that IR-related disorders, such as the metabolic syndrome and type-2 diabetes, are also associated with neurocognitive dysfunction [30,31] and it has been suggested that the effects of IR on CNS function are probably due to the abnormalities in vascular reactivity to insulin [32]. Specifically, if a defined region of the brain is activated during cognitive functioning, this activation causes local vasodilatation to clear metabolic products [33]; however, an endothelial damage due to IR can impair such regional vasodilatation [34].…”