The role of dynapenia and obesity on cognitive function in older adults

Dynapenia and obesity have been independently associated with cognitive decline in older adults, but their co-occurring effects has not been well-studied. The study objective is to examine the relationship between dynapenic-obesity and cognitive impairment in older adults 75 years and older with normal or high cognitive function at baseline over 12 years of follow-up. We hypothesize that those with dynapenic obesity will have greater odds of cognitive function impairment than those with dynapenia only, obesity only, or no dynapenia no obesity (reference group).

A total of 761 participants with a mean age of 81.5 and Mini-Mental State Examination (MMSE) > 21 at baseline were divided into four groups: no dynapenia no obesity (n = 316), obesity only (n = 142), dynapenia only (n = 217), and dynapenic obesity (n = 86). Measures included socio-demographics, medical conditions, body mass index, depressive symptoms, handgrip strength, and limitations in activities of daily living. We performed a mixed models estimate for cognitive decline for these groups over a 12-year period. Handgrip strength (HGS) was measured with a handgrip dynamometer and cognitive function was assessed with MMSE.

Participants in the dynapenia-obesity group experienced a greater (β = - 1.29, Standard Error = 0.60, p-value = 0.0316) cognitive decline over time compared to those in the no dynapenia and no obesity group, after controlling for all covariates.

Older adults with dynapenic-obesity were at high risk of cognitive decline over time. These findings highlight the need for interventions that target both conditions in this population to help maintain cognitive health. Community-based strength training programs and educational initiatives on nutrition and diet can help older adults reduce their risk of age-related cognitive decline.