Endocrine Abstracts

Recent studies revealed that the elevated tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) serum levels were associated with body fat, especially visceral adiposity, in obese healthy subjects. We investigated the relationship between circulating TNF-alpha and IL-6, parameters of body fatness, and the metabolic syndrome in chronic renal failure maintenance hemodialysis patients.

Methods: We explored the relationships between fatness and visceral obesity parameters [by anthropometry and bioelectrical impedance analysis] and adipocytokines TNF-alpha and IL-6 by enzyme-linked immunosorbent assay, and examined their associations with components of metabolic syndrome, in 56 [37 female (66%) and 19 male (34%)] patients on chronic maintenance hemodialysis, with median 48 months (IQR 24.5–82.0) dialysis duration.

Results: According to tertiles of total body fat percents we selected 28 well-nourished or middle-malnourished (12.5<FAT_%≤25.6) and 28 overweight or obese (FAT_%>25.6) HD patients for our study. The prevalence of metabolic syndrome with higher value of IR-HOMA was present in 16 (57%) overweight and in 12 (43%) nonobese HD patients. Levels of circulating TNF-alpha [221.66 (110.50–332.16) pg/ml vs. 181.87 (90.30–272.70) pg/ml, P=0.04; 247.32 (123.48–481.14) pg/ml vs. 212.46 (58.90–338.58) pg/ml, P=0.75] were higher in patients with metabolic syndrome than without it, but only in obese group. In multivariate regression analyses FAT_% and leukocyte number were independent predictors of the circulating TNF-alpha levels (Adjusted R²=0.48, P=0.02).

Conclusion: Our results showed that circulating levels of TNF-alpha was related with metabolic syndrome in overweight HD patients. General adiposity, as a strong inflammatory stimulus and total white blood cell count, as participant of low-grade inflammation, explained 48% of variation in circulating TNF-alpha levels in overweight hemodialysis patients.