Research Abstracts
The effect of long-term weight-loss intervention strategies on the dynamics of pancreatic-fat and morphology: An MRI RCT study.
Tene, L., I. Shelef, D. Schwarzfuchs, Y. Gepner, A.Y. Meir, G. Tsaban, H. Zelicha, A. Bilitzky, O. Komy, N. Cohen, N. Bril, M. Rein, D. Serfaty, S. Kenigsbuch, Y. Chassidim, B. Sarusy, U. Ceglarek, M. Stumvoll, M. Blüher, J. Thiery, M.J. Stampfer, A. Rudich, I. Shai, 2018. The effect of long-term weight-loss intervention strategies on the dynamics of pancreatic-fat and morphology: An MRI RCT study. Clinical Nutrition ESPEN. 24:82-89.
Background & aims: The ability to mobilize pancreatic-fat and the meaning of decreased fat in the pancreas remain controversial. We followed the dynamics of pancreatic-fat and its morphology during various long weight-loss induced lifestyle-interventions. Methods: In isolated workplace with monitored/provided lunch, we randomly assigned healthy persons with abdominal obesity or dyslipidemia for one of two 18-month equal-caloric diets: low-fat (LF) or Mediterranean/low-carbohydrate (Med/LC, with provided 1oz walnuts/day), with or without added moderate exercise (supervised gym membership). We used magnetic-resonance-imaging to quantify pancreatic-fat and morphology. Results: At baseline, 277 eligible participants (mean age = 48 years; 88% men; pancreatic-fat = 17.4 ± 5.1%) had higher pancreatic-fat in men (17.7 ± 4.9% vs 14.9 ± 5.5% in women; p = 0.004). Following 18-month intervention (adherence = 86.3%) and moderate weight-loss (mean = −3.0 ± 5.5 kg), pancreatic-fat decreased moderately but significantly (−0.26 ± 2.18% units; p = 0.049). Med/LC diet induced a greater decrease in pancreatic-fat compared to LF (p = 0.043), and the combination of Med/LC diet + exercise exhibited the highest reduction (−0.69% units) as compared to LF diet without exercise (+0.12%units; p = 0.027 between groups). In multivariate regression models, after further adjusted for visceral adipose-tissue (ΔVAT), pancreatic-fat loss associated with both decreases in pancreatic-morphology ratio (perimeter divided by area; beta = 0.361; p < 0.001) and superficial-subcutaneous adipose-tissue loss (beta = 0.242; p = 0.001), but not with changes in intrahepatic-fat (beta = −0.034; p = 0.638). Pancreatic-fat loss associated with increased intake of polyunsaturated-fat (beta = −0.137; p = 0.032), as with improved high-density lipoprotein-cholesterol (HDL; beta = −0.156; p = 0.023) and triglycerides/HDL ratio (beta = 0.162; p = 0.015), independently of ΔVAT, but not with glycemic–control parameters (e.g. HbA1c, HOMA-IR and HOMA-beta; p > 0.2 for all). Conclusions: Pancreatic-fat loss is mainly associated with improved lipid, rather than glycemic profiles. Med/LC diet, mostly with exercise, may benefit pancreatic-fat loss. Pancreatic-morphology could serve as a biomarker of pancreatic-fat state.