title: Association of bioimpedance spectroscopy-based volume estimation with postdialysis hypotension in patients receiving hemodialysis.
abstract: Clinical examination to determine the dry weight of patients on hemodialysis (HD) has been problematic, with studies showing discordance between physician assessment and objective measures of volume status.We studied the association between predialysis bioimpedance spectroscopy (BIS)-based estimates of fluid overload and postdialysis hypotension in 635 patients in the United States Renal Data System ACTIVE/ADIPOSE (A Cohort study To Investigate the Value of Exercise/Analyses Designed to Investigate the Paradox of Obesity and Survival in ESRD) study receiving HD in 2009-2011. We recorded predialysis and postdialysis weight and blood pressures over 3 consecutive HD sessions and performed BIS before a single session. Using a previously reported method of estimating normohydration weight, we estimated postdialysis fluid overload (FOpost ) in liters. We used logistic regression with extracellular water/total body water (ECW/TBW) or estimated FOpost as the primary predictor and 1 or more postdialysis systolic blood pressures less than 110 mmHg as the dependent variable. Models were adjusted for age, sex, race, ultrafiltration rate per kilogram of body weight, end-stage renal disease vintage, diabetes mellitus, heart failure, and albumin. Higher ECW/TBW was associated with lower odds of postdialysis hypotension (odds ratio [OR] 0.35, 95% confidence interval [CI] 0.15-0.84 per 0.1, P = 0.02). Every liter of FOpost was associated with lower adjusted odds of postdialysis hypotension (OR 0.86, 95% CI 0.79-0.95, P = 0.003). Prospective studies are needed to determine whether this application of BIS could improve current clinical efforts to minimize episodes of postdialysis hypotension without leading to volume overload.
authors.affiliation: Division of Nephrology, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
authors.forename: Adrian P
authors.initials: AP
authors.lastname: Abreo
authors.affiliation: Division of Nephrology, Stanford University School of Medicine, Palo Alto, California, USA.
authors.forename: Glenn M
authors.initials: GM
authors.lastname: Chertow
authors.affiliation: Division of Nephrology, University of California Davis, Davis, California, USA.
authors.forename: Lorien S
authors.initials: LS
authors.lastname: Dalrymple
authors.affiliation: Division of Nephrology, University of California Davis, Davis, California, USA.|Department of Biochemistry and Molecular Medicine, University of California Davis, Davis, California, USA.
authors.forename: George A
authors.initials: GA
authors.lastname: Kaysen
authors.affiliation: Division of Nephrology, University of California, San Francisco, California, USA.|Department of Epidemiology & Biostatistics, University of California, San Francisco, California, USA.|Nephrology Section, San Francisco VA Medical Center, San Francisco, California, USA.
authors.forename: Kirsten L
authors.initials: KL
authors.lastname: Johansen
mesh_terms: D000368:Aged; D015331:Cohort Studies; D017097:Electric Impedance; D005260:Female; D006801:Humans; D007022:Hypotension / Q000209:etiology*; D007676:Kidney Failure, Chronic / Q000401:mortality / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D006435:Renal Dialysis / Q000009:adverse effects* / Q000379:methods
keywords: Bioimpedance spectroscopy; end-stage renal disease; hemodialysis; volume status