Alternative surrogate measurements of central body shape and fat accumulation are not superior indicators of cardiometabolic risk when compared against the currently recommended measurements of waist circumference and BMI, according to findings published in Clinical Nutrition.
“Height- or BMI-normalized markers of central fat distribution without or with inclusion of lipid parameters have been, however, recently proposed as potential, more specific [waist circumference]-based indicators of central fat accumulation,” Rocco Barazzoni, MD, PhD, of the department of medical, surgical and health sciences at the University of Trieste, Italy, and colleagues wrote in the study background. “Clinical interest in [a body shape index] has also been raised by its association and higher predictive value for all-cause mortality compared to other anthropometric markers, including BMI. Whether height- and BMI-normalized surrogate markers of central visceral fat predict cardiometabolic risk in the general population and particularly in high-risk overweight-obese individuals remains, however, largely undefined.”
Barazzoni and colleagues analyzed data from 1,965 adults participating in the North-East Italy MoMa epidemiologic study, which investigated the prevalence of metabolic syndrome in municipalities in Pordenone, Italy (mean age, 49 years; mean BMI, 26.7 kg/m²). Participants provided fasting blood samples to assess plasma glucose, triglycerides, total and HDL cholesterol and insulin concentrations. Researchers calculated BMI, waist circumference and surrogate markers of central adiposity, including weight to height ratio, body roundness index, a body shape index (ABSI) and visceral adiposity index (VAI). Researchers investigated the associations between the surrogate markers and insulin resistance, as measured by homeostatic model of insulin resistance and metabolic syndrome and evaluated baseline values as predictors of future insulin resistance and metabolic syndrome in a subgroup of participants with overweight or obesity who underwent 5-year follow-up (n = 263; mean age, 55 years; mean BMI, 30.7 kg/m²).
Researchers found that weight to height ratio and body roundness index were similarly associated with baseline insulin resistance and metabolic syndrome prevalence after adjustments (P < .001) and found that all markers predicted 5-year insulin resistance and metabolic syndrome risk (P < .001). In contrast, researchers did not observe associations between ABSI and 5-year risk for insulin resistance or metabolic syndrome. When including lipid parameters, BMI-normalized VAI was also a positive predictor of 5-year risk for insulin resistance and metabolic syndrome, according to researchers.
The researchers noted that ABSI and VAI showed “profoundly different” abilities in cardiometabolic risk prediction, despite using a similar, BMI-normalized, waist-circumference-based equation; however, the ABSI equation does not include transformed plasma triglyceride and HDL cholesterol concentrations, which may play a key role in the ability of the VAI to predict cardiometabolic risk. To test the hypothesis, researchers calculated receiver operating characteristic (ROC) analyses for 5-year metabolic syndrome prediction by VAI excluding plasma triglyceride and HDL cholesterol concentrations and 5-year metabolic syndrome prediction by ABSI including plasma triglyceride and HDL cholesterol concentrations.
“In agreement with our hypothesis, VAI no longer predicted 5-year [metabolic syndrome], whereas ABSI became its strongest predictor in ROC analyses,” the researchers wrote. “The current results strongly support the concepts that BMI-normalized surrogate markers of central fat accumulation per se are weak predictors of overweight- and obesity-associated cardiometabolic risk; [the] inclusion of plasma triglycerides and HDL cholesterol strongly improves cardiometabolic risk prediction of BMI-normalized central fat surrogate markers.”
The researchers noted that weight to height ratio and body roundness index effectively identify and predict metabolic complications, but they offer “no advantage” over waist circumference and BMI. – by Regina Schaffer
Disclosures: The authors report no relevant financial disclosures.