Abdominal fat deposition is associated with increased inflammation, protein-energy wasting and worse outcome in patients undergoing haemodialysis

Abstract

Objective: The role of obesity in promoting or preventing the complications of haemodialysis patients remains unclear, with several studies suggesting that obesity may even be beneficial. We tested the hypothesis that abdominal fat deposition in HD patients is a risk factor associated with both increased inflammation and protein-energy wasting (PEW), as well as elevated mortality risk.

Methods: A cross-sectional study with mortality follow-up [median 41 (interquartile range 25-47) months] of haemodialysis patients [n = 173, 100 men, aged 65 (51-74) years]. Abdominal fat deposition was assessed by means of a conicity index (Ci), which estimates fat accumulation in the abdomen as the deviation of body shape from a cylindrical towards a double-cone shape (i.e. two cones with a common base at the waist level). The Ci was studied with regard to baseline inflammatory, anthropometric and nutritional markers, including subjective global assessment (SGA).

Results: Across increasing tertiles of the Ci, patients were older, fatter and more inflamed (P < 0.01 for all). At the same time, they presented a higher prevalence of PEW (SGA >1), reduced handgrip strength and lower S-creatinine (P < 0.01 for all). An increased abdominal fat deposition was associated with worse outcome independently of age, sex, comorbidities and dialysis vintage [Cox HR 1.93 (95% CI = 1.06-3.49)], but the predictive value disappeared following adjustment for interleukin-6 (IL-6) and PEW.

Conclusion: Abdominal fat deposition in haemodialysis patients is linked to both inflammation and PEW, resulting in an increased mortality risk. Our results support the idea that regional differences in adiposity accumulation may have diverse implications on patient outcome.