ASSESSMENT OF DRY BODY-WEIGHT IN HEMODIALYSIS-PATIENTS BY THE BIOCHEMICAL MARKER CGMP

We investigated whether cGMP might be a suitable marker of ideal weight in chronic haemodialysis patients. In 20 patients on chronic haemodialysis (10 males, 10 females, mean age 55.5±7.4 years; mean interdialytic weight gain 2.4±1.1 kg) we determined plasma ANP and cGMP values before and after several haemodialysis treatments. ANP and cGMP before haemodialysis were markedly elevated (ANP 255 + 190 pg/ml; cGMP 28.6 + 16.2 pmol/ml). A significant decrease was found after haemodialysis (ANP 169±88 pg/ml; cGMP 13.5 + 7.4 pmol/ml). These values were still well above normal. There was a significant positive correlation between excessive body-weight ΔP (difference between actual weight and estimated ideal weight), indicating fluid overload and ANP before (r = 0.57; P<0.001) and after haemodialysis (r = 0.47; P<0.001) as well as cGMP before (r = 0.42; P<0.01) and after haemodialysis (r = 0.85; P< 0.0001). With cGMP and ΔP after haemodialysis, the correlation appeared to be close enough for clinical application. All patients with a cGMP value of 18 pmol/ml or more after haemodialysis had an excessive body-weight of at least 0.5 kg. We conclude from these data that the plasma cGMP value determined immediately after haemodialysis is a sensitive marker for hyperhydration in patients with end-stage renal disease. © 1990 European Dialysis and Transplant Association-European Renal Association.