Metabolic syndrome and 16-year cognitive decline in community-dwelling older adults

To determine whether metabolic syndrome is associated with accelerated cognitive decline in community-dwelling older adults.

A longitudinal study of 993 adults (mean 66.8 ± 8.7 years) from the Rancho Bernardo Study. Metabolic syndrome components, defined by 2001 NCEP-ATP III criteria, were measured in 1984-1987. Cognitive function was first assessed in 1988-1992. Cognitive assessments were repeated approximately every 4 years, for a maximum 16-year follow-up. Mixed-effects models examined longitudinal rate of cognitive decline by metabolic syndrome status, controlling for factors plausibly associated with cognitive function (diabetes, inflammation).

Metabolic syndrome was more common in men than women (14% vs. 9%, p = .01). In women, metabolic syndrome was associated with greater executive function and long-term memory decline. These associations did not differ by inflammatory biomarker levels. Diabetes did not alter the association of metabolic syndrome with long-term recall but modified the association with executive function: metabolic syndrome was associated with accelerated executive function decline in diabetic women only. Metabolic syndrome was not related to rate of decline on any cognitive measure in men.

Metabolic syndrome was a risk factor for accelerated cognitive decline, but only in women. Prevention of metabolic syndrome may aid in maintenance of cognitive function with age.