Markers of adiposity, insulin resistance, prediabetes and cognitive function at baseline of the Brazilian Longitudinal Study of Adult Health (ELSA – Brasil)

Aim: The aim of the study is to investigate whether adiposity markers, insulin resistance and prediabetes are associated with cognitive performance in middle-aged men and women without diabetes. Methods: Cross-sectional study with 11,115 adults without diabetes (34–64 years old). Cognitive performance was tested by word-list learning, word-list delayed recall, word recognition tests, semantic and phonemic verbal fluency tests and trail making test B. Linear regression models and generalized linear regression with logarithmic links between the cognitive tests and anthropometric indicators (body mass index [BMI]), insulin resistance (Homeostasis Model Assessment for Insulin Resistance [HOMA-IR]), and prediabetes (impaired glucose tolerance) were stratified by sex. The results were adjusted for age, education, comorbidities, health-related behaviors, waist circumference, and lipids. Results: Among women, higher BMI was associated with poorer performance on phonemic verbal fluency test (β-0.02 [−0.04; −0.01]) and memory tests (β-0.05 [−0.07; −0.02]). Higher HOMA-IR was associated with poorer cognitive performance in memory (β-0.11 [−0.19; −0.01]) and phonemic verbal fluency tests (β-0.12 [−0.20; −0.04]). In men, HOMA-IR (β-0.15 [−0.25; −0.04]) and prediabetes (β-0.35 [−0.69; -0.03]) were associated with poorer performance on memory tests. Conclusions: We found a significant association of BMI and HOMA-IR with cognitive performance in young and middle-aged adult women without diabetes. In men, we found an association between HOMA-IR and prediabetes and poorer performance on memory tests.