Metabolic syndrome associated with poorer cognition in midlife
Middle-aged Hispanic adults with metabolic syndrome were more likely to have lower global neurocognitive scores and to satisfy criteria for low mental status, both early hallmarks of dementia, than their peers without metabolic syndrome, according to findings published in Diabetes Care.
“More than half of middle-age and older Latinos meet metabolic syndrome criteria, much higher than the rates among black and white adults,” Hector M. Gonzalez, PhD, associate professor of neurosciences at the Shiley-Marcos Alzheimer’s Disease Research Center, UC San Diego School of Medicine, told Endocrine Today. “Middle-age may be a particularly vulnerable period to the effects of metabolic syndrome on cognitive aging.”
Gonzalez and colleagues analyzed cross-sectional data from 9,136 adults aged 45 to 74 years participating in the Hispanic Community Health Study/Study of Latinos, an epidemiologic study of Hispanic and Latino adults from the Bronx, New York; Chicago; Miami-Dade County, Florida; and San Diego (54.6% women; mean age, 56 years). Participants completed four neurocognitive tests in English or Spanish in face-to-face interviews, including the Six-Item Screener, Brief Spanish English Verbal Learning Test (B-SEVLT), Word Fluency test and the Digit Symbol Subtest, a mental processing speed and executive function test. Metabolic syndrome status was defined by International Diabetes Federation criteria. Researchers used generalized linear models to examine the association between metabolic syndrome and neurocognition.
Within the cohort, 54% satisfied criteria for metabolic syndrome, with prevalence varying by age — 50.4% among adults aged 45 to 64 years and 67.2% among adults aged 65 to 74 years. Those who met metabolic syndrome criteria were more likely to be older women, according to researchers.
Overall, adults with metabolic syndrome had lower average global neurocognitive performance and were more likely to satisfy criteria for low mental status, the researchers wrote. Metabolic syndrome status was inversely associated with global neurocognition (beta = –0.07), B-SVELT score (beta = –0.07), Word Fluency score (beta = –0.15) and Digit Symbol Subtest score (beta = –0.15); however, metabolic syndrome status was not associated with B-SVELT-recall or mental status.
Age significantly modified the associations between metabolic syndrome and learning and memory measures, according to the researchers.
Inflammation, measured by C-reactive protein levels, did not affect the relationship between metabolic syndrome and neurocognition, according to the researchers.
“Our finding supports and extends current hypotheses that midlife may be a particularly vulnerable period for the development of neurocognitive decline,” the researchers wrote. “Secondly, we found that midlife episodic learning and memory were particularly vulnerable to [metabolic syndrome] effects, which has direct implications for the development of memory impairment, which is the hallmark of [Alzheimer’s disease],” they wrote.
Additionally, the researchers noted that the finding of no association between inflammation levels, metabolic syndrome and neurocognitive performance differs from previous studies of older Latino adults, which have suggested that such a link exists.
Gonzalez said clinicians should advise their middle-aged Latino patients that managing weight, glucose and other metabolic syndrome elements are important for maintaining healthy cognitive aging.
“We need to know more about how obesity and diabetes impacts middle-age brain health and disease, and if intervening in metabolic syndrome earlier would pay dividends in preventing Alzheimer’s disease and related dementias later in life,” Gonzalez said. – by Regina Schaffer
For more information:
Hector M. Gonzalez, PhD, can be reached at the Shiley-Marcos Alzheimer’s Disease Research Center, University of California, 9500 Gilman Drive, #0949, La Jolla, CA 92093; email: firstname.lastname@example.org.
Disclosures: The authors report no relevant financial disclosures.