HealthDay News — Higher serum fasting insulin and insulin resistance predict poorer verbal fluency and a steeper decline in future verbal fluency, according to a study published online April 5 issue of Diabetes Care.
Laura L. Ekblad, MD, from the University of Turku in Finland, and colleagues examined data from the Finnish nationwide, population-based Health 2000 Health Examination Survey and its 11-year follow-up, the Health 2011 study (3,695 participants; mean age at baseline, 49.3 years; 55.5% women). The authors sought to assess the roles of homeostatic model assessment of insulin resistance (HOMA-IR), fasting insulin and glucose, glycated hemoglobin, and high-sensitivity C-reactive protein (hs-CRP) as predictors of cognitive performance.
The researchers found that higher baseline HOMA-IR and fasting insulin levels were independent predictors of poorer verbal fluency performance (P=0.0002 for both) and of a greater decline in verbal fluency over follow-up (P=0.004 for both). Word-list learning and word-list delayed recall scores were not predicted by baseline HOMA-IR or insulin. There were no interactions between cognitive test performance and HOMA-IR and apolipoprotein E ε4 genotype, hs-CRP, or type 2 diabetes. Baseline levels of fasting glucose and hs-CRP levels were not associated with cognitive functioning.
“Prevention and treatment of insulin resistance might help reduce cognitive decline later in life,” the authors write.