Authors: K. Kantartzis, I. Rettig, H. Staiger, J. Machann, F. Schick, L. Scheja, A. Gastaldelli, E. Bugianesi, A. Peter, M.B. Schulze, A. Fritsche, H.-U. Häring, N. Stefan
Summary:
Background: In clinical practice, there is a strong interest in non-invasive markers of non-alcoholic fatty liver disease (NAFLD). Our hypothesis was that the fold-change in plasma triglycerides (TG) during a 2-h oral glucose tolerance test (fold-change TGOGTT) in concert with blood glucose and lipid parameters, and the rs738409 C>G single nucleotide polymorphism (SNP) in PNPLA3 might improve the power of the widely used fatty liver index (FLI) to predict NAFLD.
Methods: The liver fat content of 330 subjects was quantified by 1H-magnetic resonance spectroscopy. Blood parameters were measured during fasting and after a 2-h OGTT. A subgroup of 213 subjects underwent these measurements before and after 9 months of a lifestyle intervention.
Results: The fold-change TGOGTT was closely associated with liver fat content (r = 0.51, P < 0.0001), but had less power to predict NAFLD (AUROC = 0.75) than the FLI (AUROC = 0.79). Not only was the fold-change TGOGTT independently associated with liver fat content and NAFLD, but so also were the 2-h blood glucose level and rs738409 C>G SNP in PNPLA3. In fact, a novel index (extended FLI) generated from these and the usual FLI parameters considerably increased its power to predict NAFLD (AUROC = 0.79–0.86). The extended FLI also increased the power to predict changes in liver fat content with a lifestyle intervention (n = 213; standardized beta coefficient: 0.23–0.29).
Conclusion: This study has provided novel data confirming that the OGTT-derived fold-change TGOGTT and 2-h glucose level, together with the rs738409 C>G SNP in PNPLA3, allow calculation of an extended FLI that considerably improves its power to predict NAFLD.
Source:
Diabetes & Metabolism; 2017