#3811 Adiposity in haemodialysis patients: measuring obesity beyond body mass index

Abstract

Abstract Background and Aims Obesity is a complex chronic multifactorial pathology characterised by an accumulation of often dysfunctional adipose tissue (AT). Leading scientific societies propose to replace the term ‘obesity’ by ‘Chronic Adipose-Based Disease’ or ‘Chronic Adipose Metabolic Disease’ to reflect the metabolic disturbances due to accumulation and dysfunction of AT. Classical techniques such as Body Mass Index (BMI) or Waist Circumference (WC) may not detect those patients with higher cardiometabolic risk phenotypes. In addition, in the nephrological setting, the assessment of obesity may be hampered by edema and hyperhydration. Aim: To determine the prevalence of obesity in haemodialysis (HD) patients according to gender and using different health indicators. Method Retrospective multicentre study of 301 HD patients. Clinical data including gender, height and dry weight (DW) will be collected. Body composition will be assessed by Inbody® S10 segmental multifrequency bioimpedance (BIA-MF) post-dialysis. BMI will be calculated based on BP and height at the time of data collection. Obesity is defined according to BMI ≥30 kg/m2 and body fat percentage (BFp) >25% men and >33% women. Visceral fat will be expressed as visceral fat area (VFA) obtained by BIA-MF considering a risk value ≥100 cm3. Risk CC cut-off point ≥102 cm men and ≥88 cm women. Kolmogorov-Smirnov test to assess normality and parametric statistics to assess difference between groups: Student's t-test and Chi-square for quantitative and categorical variables respectively. Statistical significance P < 0.05. Results Of the 301 patients, 189 (62.8%) were male with a mean age 69.3 ± 14.9 years and 112 (37.2%) were female with a mean age 66.7 ± 16.4 years (NS). The prevalence of obesity (BMI ≥30 kg/m2) was 13.2% in men and 28.6% in women (P < 0.013). According to the PGC, the obesity rate was 47.6% in men and 48.2% in women (NS). Among patients with a BMI<30 kg/m2, we observed that 34.9% of men and 23.2% of women had a PGC in the obese range (P = 0.033). In relation to the distribution of visceral adipose tissue, 38.9% had a VFA value ≥100 cm3 (29.6% of men and 54.5% of women (P < 0.001)]. 22.6% (68) of patients had elevated CC [6.6% (23) men vs. 31.2% (45) women (P < 0.001)]. We observed that 18% (56) of patients with a CC in the normal range had VFA values ≥100 cm3 [20.1% (38) men vs. 16.1% (18) women (NS)]. Conclusion In our study, a poor correlation between BMI, PGC and AGV was observed, so we conclude that both the classical indicator of BMI and CC underestimate the ‘real’ obesity rate. We believe that the assessment of HD patients should not only be multidisciplinary, but should also shift from a weight-centred approach to a body composition-based approach. This will allow us to target patients with higher cardiometabolic risk phenotypes and initiate better therapeutic strategies.