TOPLINE:
Whether they have normal weight, overweight, or obesity, individuals with metabolically healthy (MH) phenotypes show a lower frequency of impaired glucose metabolism than their unhealthy counterparts across all weight categories.
METHODOLOGY:
- The concepts of MH overweight and MH obesity refer to a subset of people who exhibit an absence of cardiometabolic risk factors despite excess body fat, but the prevalence of prediabetes has not been investigated by metabolic phenotype and body mass index (BMI).
- This study first validated the use of estimated glucose disposal rate (eGDR), an index of insulin sensitivity calculated from clinical variables, in 350 individuals without diabetes (mean age, 37 years; 219 women; mean BMI, 30.3) from the EUGENE2 project who had varying glucose tolerance values originally assessed by insulin-stimulated glucose disposal.
- Researchers then stratified 2201 participants without diabetes (mean age, 46 years; White; 1290 women; mean BMI, 31.2) from the CATAMERI study according to BMI into three groups — individuals with normal weight (BMI, 18-24.9), overweight (BMI, 25-29.9), and obesity (BMI, ≥ 30).
- The men and women in each BMI group were separated into quartiles of insulin sensitivity based on eGDR index:
- In the normal weight group, men and women were defined as MH in the top three eGDR quartiles and metabolically unhealthy (MU) in the lowest quartile.
- In the overweight and obesity groups, people were defined as MH in the top eGDR quartile and MU in the lower three quartiles.
- Impaired glucose tolerance (IGT), impaired fasting glucose (IFG), and combined IFG+IGT conditions (from an oral glucose tolerance test) were compared in individuals without diabetes based on MH or unhealthy phenotypes across normal weight, overweight, and obese categories.
TAKEAWAY:
- eGDR demonstrated good accuracy in detecting individuals with higher insulin sensitivity in the EUGENE2 cohort.
- The MH overweight and MH obesity groups showed comparable glycemic parameters as the MH normal weight group, whereas the MU overweight and MU obesity groups exhibited higher A1c levels and fasting and 2-hour post-load glucose than the MH normal weight group.
- The frequencies of IFG, IGT, and IFG+IGT conditions were similar among the MH normal weight, MH overweight, and MH obesity groups but were higher in the MU overweight and MU obesity groups than in the MU normal weight group.
- Furthermore, compared with those in the MH normal weight group, the odds of prediabetes were at least two times higher in the MU obesity (odds ratio [OR], 2.54; P < .001) and MU overweight (OR, 2.06; P < .001) groups but not significantly different in the MU normal weight, MH obesity, and MH overweight groups.
IN PRACTICE:
The authors wrote, "Overall, the results of this cross-sectional study support the notion that metabolically healthy individuals with overweight or obesity have a more favorable metabolic risk profile in comparison to metabolically unhealthy subjects with overweight or obesity."
SOURCE:
The study was conducted by Chiara M.A. Cefalo, MD, Department of Clinical and Molecular Medicine, Sapienza University of Rome, Rome, Italy, and was published online in Diabetes, Obesity and Metabolism.
LIMITATIONS:
There was no consensus on the parameters and cutoff values for defining metabolic health status, allowing for potential variations in results. The study design suggested an association with prevalent IFG and IGT conditions but not with incident IFG and IGT conditions. All participants in this study were White, limiting the generalizability of its findings.
DISCLOSURES:
The study was supported by Sapienza University of Rome and the Italian Ministry of University. The authors declared no conflicts of interest.