Convection volume, beta 2-microglobulin and alpha 1-microglobulin reduction ratios, and body composition in pre-dilution online haemodiafiltration

Aim The effect of convection volume (CV) in patients on pre-dilution online haemodiafiltration (Pre-OL-HDF) was evaluated. Methods We conducted a retrospective, cross-sectional study in 126 patients on Pre-OL-HDF. Dialysis conditions, laboratory data, and same day post-dialysis body composition measurements using bioimpedance spectroscopy were assessed. Patients were divided into two groups according to their CV: >= median value and < median value. Linear regression analyses for reduction ratios (RRs) of beta 2-microglobulin and alpha 1-microglobulin, and body composition, were conducted. Results Age, dialysis vintage, and CVs of the study patients were 64 +/- 12 years, 81 (48-154) months, and 43.2 (38.5-55.9) L/session, respectively. The higher CV (>= 43 L/session) group (n = 66) had significantly higher RRs of beta 2-microglobulin and alpha 1-microglobulin, lean tissue index, body cell mass index, total body water (TBW), extracellular water (ECW), and intracellular water (ICW) compared with the lower CV (< 43 L/session) group (n = 60, p < .01). Serum albumin and fat tissue index were not significantly different between the groups. CV/ECW, CV/TBW, and CV/ICW but not un-adjusted CV, were significant determinants for beta 2-microglobulin and alpha 1-microglobulin RRs (p < .05). Lean tissue and body cell mass indexes, but not the fat tissue index, showed significant associations with CV, and RRs of beta 2-microglobulin and alpha 1-microglobulin (p < kb.05). Conclusions Among patients on Pre-OL-HDF, higher values in the lean tissue index and body cell mass index were observed in those with higher CV versus lower CV, and CV adjusted to body water may be useful to prescribe individualized conditions for Pre-OL-HDF.