Impact of Dietetic Intervention on Skin Autofluorescence and Nutritional Status in Persons Receiving Dialysis: A Proof of Principle Study

Abstract

Advanced glycation end-products (AGEs) are uremic toxins that result from oxidative stress and food consumption. It has been reported that markers of malnutrition are more important determinants of increased skin autofluorescence (SAF), a measure of AGE accumulation and risk factor for mortality, than high dietary AGE intake in a hemodialysis (HD) population, suggesting that correcting malnutrition may decrease SAF. We investigated this hypothesis in a single-center, nonrandomized proof-of-principle study. We enrolled 27 patients on HD and one on peritoneal dialysis with malnutrition who received individualized nutritional advice and support over 6months. SAF was measured at baseline, 3 months, and 6months. Dietary intake and nutritional status were assessed at baseline and 6months. Results were compared with a control group of malnourished patients on dialysis (n=41 HD and 8 peritoneal dialysis) from a previous observational study. The intervention group showed a significant increase in dietary intake, including AGEs, Subjective Global Assessment score, and serum albumin, while SAF levels remained stable for over 6months (3.8±0.7 arbitrary units [AU] vs. 3.7±0.7 AU; P=.3). Conversely, in the control group, SAF increased significantly during the observation period (3.5±0.9 AU vs. 3.8±1.2 AU; P=.03) during which there was no improvement in nutritional intake and other markers of nutrition, although dietary AGE intake and Subjective Global Assessment score did increase. Dietetic support was associated with stable SAF levels in this proof-of-principal study despite an increase in dietary AGE intake, suggesting that interventions to improve nutrition may be important in preventing the rise in SAF observed in malnourished dialysis populations. Further long-term studies are needed to test this hypothesis and evaluate the impact on survival.