Differential Impact of Changes in Adiposity Distribution on Insulin Resistance and Adiponectin Variations Over 4 Years in Normal Weight Young Adults

Abstract

The aim of the study was to evaluate the influence of weight gain and changes in adiposity distribution on insulin resistance and circulating adiponectin variations over 4 years in free-living normal weight young adults. In this prospective observational cohort (n=42 women, 18 men), anthropometric measurements and blood samples were collected in the fasting state at baseline and at 4 years. Insulin resistance was estimated using the homeostatic model assessment (HOMA-IR). Circulating adiponectin levels were determined by radioimmunoassay. To investigate increase in adiposity more specifically, subsidiary analyses were performed in a subgroup of individuals (n=31) who gained adiposity over the course of the 4-year follow-up (defined as gain >1% in percent body fat). Regression analyses were performed to adjust for sex, age, parental education, lifestyle, and fitness levels. At baseline, the participants were young adults (age=20.0 years old) in the normal weight range [body mass index (BMI)=22.7 kg/m2 (IQR=21.1-24.4)]. Median change in body fat percentage was +1.4% (IQR=-0.3-3.4; p=0.01) and in waist circumference was +1.2 cm (IQR=-2.6-5.3; p=0.05). In the subgroup of individuals who gained more than 1% body fat, increase in HOMA-IR was associated with an increase in BMI (r=0.44; p=0.01; p<0.01 in fully adjusted model), while decrease in adiponectin levels was associated with an increase in waist circumference (r=-0.38; p=0.03) but this was no longer significant after adjustment for sex and other potential confounders (p=0.14). In a population of young adults, small variations in adiposity within the normal weight range were associated with increase in insulin resistance.

Comparison of Insulin Resistance and β-Cell Dysfunction Between the Young and the Elderly in Normal Glucose Tolerance and Prediabetes Population: A Prospective Study

“…As reported in our study, physical activity was positively associated with log HOMA2-B in both age groups, therefore, lifestyle modification such as physical activities or reducing weight gain bring benefit to preserve β-cell function in individuals with prediabetes [32]. Drug such as vildagliptin may also help to repair impairments in pancreatic β-cell function and insulin resistance [33].…”

Endometria from Obese PCOS Women with Hyperinsulinemia Exhibit Altered Adiponectin Signaling

“…The link between FAI, IR and adiponectin levels may exist for several reasons. Prospective studies have shown a relationship between IR and decreased adiponectin levels with weight gain and increased waist circum ference [39]. Furthermore, since androgens promote central adi posity and visceral adipose deposition, differences in adipose tissue distribution may influence the secretion of the different adipocytokines and pro-inflammatory proteins, such as TNF-α and IL6, which are upregulated in PCOS patients [40]; these cytokines may downregulate the expression of adiponectin.…”

Adipose Tissue Dysfunction: Clinical Relevance and Diagnostic Possibilities

“…Adipose tissue quantity, as measured with either BMI or waist circumference (WC) is related to plasma concentrations of adipokines, to morphologic characteristics of adipose tissue, and to the development of the metabolic syndrome, DM2, and vascular diseases [39][40][41]. Pro-inflammatory adipokines (IL-6, IL-8, IL-18, TNF-α, PAI1, and leptin) are known to be positively correlated with both BMI and WC [42][43][44][45], whereas the anti-inflammatory adiponectin is negatively correlated with BMI and WC [42][43][44][45][46]. In subcutaneous adipose tissue biopsies, IL-6 and IL-8 expression are associated with waist circumference [47].…”