Association of serum butyrylcholinesterase with concurrent dry-weight change in maintenance hemodialysis: a retrospective longitudinal study

Background Assessing nutrition-related change in maintenance hemodialysis is challenging because commonly used biomarkers such as serum albumin are influenced by inflammation and volume status. Prescribed dry weight (DW) is a clinically important treatment target, but longitudinal DW change may reflect both volume-related and nutrition-related body-mass change. Serum butyrylcholinesterase (BChE), a liver-synthesized protein, may better capture nutrition-related change in this setting. We examined whether longitudinal change in BChE was associated with concurrent change in prescribed DW and compared this association with that of albumin while accounting for volume-related change using human atrial natriuretic peptide (hANP). Methods We conducted a single-center retrospective longitudinal observational study of adults receiving maintenance hemodialysis between September 2024 and December 2025. Monthly clinical data were used to calculate concurrent 3-month changes, expressed as log-ratios (Δlog), in BChE, albumin, hANP, and prescribed DW. The primary analysis evaluated the association between ΔlogBChE and concurrent ΔlogDW across repeated 3-month windows using linear regression with patient-level cluster-robust standard errors. Multivariable models included ΔlogBChE, ΔlogAlb, and ΔloghANP. Results Ninety-six patients were included, contributing 1,248 concurrent 3-month windows. In multivariable longitudinal models, ΔlogBChE was independently associated with concurrent ΔlogDW (standardized β = 0.115; P = 0.005), whereas ΔlogAlb was not ( P = 0.39). ΔloghANP was also independently associated with ΔlogDW (standardized β = 0.144; P = 0.001). Conclusions In maintenance hemodialysis, longitudinal change in serum BChE was associated with concurrent prescribed DW change independent of albumin and hANP. These preliminary findings suggest that BChE may help contextualize prescribed DW changes as a nutrition-related biochemical signal, but prospective validation using standardized body-composition assessment is needed.