Influence of Different Haemodialysis Modalities on AGE Peptide Levels: Intradialytic versus Long-Term Results

The influence of body mass index on the accumulation of advanced glycation end products in hemodialysis patients

BACKGROUND/OBJECTIVES

The level of skin autofluorescence (AF) at a given moment is an independent predictor of mortality in hemodialysis (HD) patients. Skin AF is a measure of the accumulation of advanced glycation end products (AGEs). The aim of the study was to estimate the influence of nutrition on the 1-year increase of skin AF (ΔAF) in HD patients.

SUBJECTS/METHODS

A total of 156 HD patients were enrolled in this study. Skin AF, body mass index (BMI), superoxide dismutase, myeloperoxidase, C-reactive protein, inter-cellular adhesion molecule-1, von Willebrand factor and heart-type fatty acid-binding protein were measured four times at intervals of approximately half a year. Data from the monthly routine blood analysis were also used. Daily calorie, protein and AGE intakes were assessed from food recordings over a period of 1 week.

RESULTS

A J-shaped relation was found between baseline BMI and ΔAF (P=0.01). The lowest point of the J-shaped curve is found for BMI=24.3 kg/m(2). In the univariate analysis of the contributors to the 1-year ΔAF, we found that beside BMI=24.3 kg/m(2), AGE and calorie intakes, as well as myeloperoxidase and HD vintage, had a P <0.10. The sole independent predictor of the 1-year ΔAF was BMI=24.3 kg/m(2) (P=0.01).

CONCLUSIONS

It appears that calorie, protein and AGE intakes hardly influence the 1-year ΔAF in HD patients. BMI of HD patients of around 24 kg/m(2) resulted in a lower 1-year ΔAF.

Convective therapies versus low-flux hemodialysis for chronic kidney failure: a meta-analysis of randomized controlled trials

BACKGROUND

Although convective therapies have gained popularity for the optimal removal of uremic solutes, their benefits and potential risks have not been fully elucidated. We conducted a meta-analysis of all randomized controlled trials comparing convective therapies with low-flux hemodialysis in patients with chronic kidney failure.

METHODS

We performed a literature search using MEDLINE (inception-December 2012), Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, scientific abstracts from meetings and bibliographies of retrieved articles. Randomized controlled trials comparing the effect of convective therapies including high-flux hemodialysis, hemofiltration or hemodiafiltration versus low-flux hemodialysis were included. Random-effects model meta-analyses were used to examine continuous and binary outcomes.

RESULTS

Sixty-five (29 crossover and 36 parallel-arm) trials were identified (n = 12 182). Convective therapies resulted in a decrease in all-cause mortality [relative risk (RR) 0.88; 95% confidence interval (CI) 0.76, 1.02, P = 0.09], cardiovascular mortality (RR 0.84; 95% CI 0.71, 0.98, P = 0.03), all-cause hospitalization (RR 0.91; 95% CI 0.82, 1.01; P = 0.08) and therapy-related hypotension (RR 0.55, 95% CI 0.35, 0.87, P = 0.01). Convective therapies also resulted in an increase in the clearance of several low-molecular-weight (urea, creatinine and phosphate), middle-sized (β-2 microglobulin and leptin) and protein-bound (homocysteine, advanced glycation end-products and pentosidine) solutes and a decrease in inflammatory markers (interleukin-6). There was no impact of convective therapies on cardiac morphological and functional parameters, and blood pressure and anemia parameters.

CONCLUSIONS

Although convective therapies are associated with improved clearance of uremic solutes, the potential long-term benefits of specific convective modalities require further study.