Endocrine Abstracts

Obesity, the condition resulting from excess of body fat, is often accompanied by chronic low-grade levels of inflammation. These have been strongly associated with the development of insulin resistance (IR). Elevated BMI has also been linked to reduced cognitive performance, especially in executive functions, independently of medical co-morbidities.

Aim of this research is to investigate whether higher cognitive resources may present a moderating, ‘protective’ role on the triplet obesity – inflammation – insulin resistance.

Community-dwelling adults (n=127, M age=37.35, S.D.=14.17, range 17–65 years; 85% females) free of major and chronic autoimmune or inflammatory diseases underwent blood test after overnight fasting. C-reactive protein (CRP), a major marker of systemic inflammation, and Homeostatic Model Assessment, a widely used method to yield IR from fasting plasma insulin and glucose concentrations, were measured. Cognitive resources were evaluated through the General Adult Mental Ability Scale (GAMA), a non-verbal measure of general intelligence.

Moderated mediation analyses were performed comparing two alternative models. In model 1 a conditional indirect effect of BMI (obesity) on HOMA (insulin resistance), which is mediated by CRP (inflammation) was tested. Our interim results showed that the strength of the association between BMI and CRP varied at different levels of cognitive ability: the effect of obesity on inflammation was stronger for persons with poorer cognitive ability (controlling for age and education level). In a second proposed model, a direct effect of CRP (inflammation) on HOMA (insulin resistance), moderated by GAMA (cognitive ability) was tested. BMI was found to exert a direct effect on HOMA but the association between CRP and HOMA was not affected by cognitive ability.