The association of body weight change and regression to normoglycemia in different phenotypes of pre-diabetes: Findings of a longitudinal cohort study

Aim

We investigated the association of a 3-year change in body weight (BW) and regression to normal glucose regulation (NGR) among different phenotypes of pre-diabetes (Pre-DM), i.e., isolated impaired glucose tolerance (iIGT), isolated impaired fasting glucose (iIFG) and combined IFG-IGT.

Research design and methods

1458 Pre-DM subjects (iIFG = 618, iIGT = 462, and IFG-IGT = 378) were assessed for 3-year change-percent in BW (2006–2008 to 2009–2011) and then followed up to 2015–2017, within the national cohort of Tehran Lipid and Glucose Study (TLGS). Binary logistic regression models were used to estimate the probability (odds ratio, ORs) of regression to NGR across categories of 3-year BW change (i.e., ≥5% BW loss, <5% BW loss, BW gain) in different phenotypes of Pre-DM.

Results

The mean age of the participants was 53.0 ± 13.7, and 46.8% were men. Over a median of 6 years of follow-up, the rate of regression to normoglycemia was 50.6, 43.2, and 12.7% in iIGT, iIFG, and combined IFG-IGT, respectively. The baseline-adjusted mean of 3-year BW change was not significantly different across Pre-DM phenotypes (0.68 ± 0.19, 0.32 ± 0.22, and 0.23 ± 0.24 kg, in iIFG, iIGT, and IFG-IGT). Three-year BW loss ≥5% was associated with a greater NGR probability in iIGT than other phenotypes (OR = 4.29 vs. 3.90 and 2.84 in IFG-IGT and iIFG, respectively). A modest reduction (<5% of initial BW) resulted in an increased chance of Pre-DM regression among subjects with iIGT (OR = 1.61, 95% CI = 1.03–2.52) but not iIFG or IFG-IGT phenotypes.

Conclusion

Short-term intensive BW loss (≥5% of initial BW) increased NGR probability in all Pre-DM phenotypes, with an order of iIGT > combined IFG-IGT > iIFG. Only iIGT takes advantage of moderate BW loss (<5% of initial BW) to increase the chance of Pre-DM regression.