title: Randomized trial of bioelectrical impedance analysis versus clinical criteria for guiding ultrafiltration in hemodialysis patients: effects on blood pressure, hydration status, and arterial stiffness.
abstract: BACKGROUND
  Chronic fluid overload is common in maintenance hemodialysis (HD) patients and is associated with severe cardiovascular complications, such as arterial hypertension, left ventricular hypertrophy, congestive heart failure, and arrhythmia. Therefore, a crucial target of HD is to achieve the so-called dry weight; however, the best way to assess fluid status and dry weight is still unclear. Dry weight is currently determined in most dialysis units on a clinical basis, and it is commonly defined as the lowest body weight a patient can tolerate without developing intra-dialytic or inter-dialytic hypotension or other symptoms of dehydration. One of the most promising methods that have emerged in recent years is bioelectrical impedance analysis (BIA), which estimates body composition, including hydration status, by measuring the body's resistance and reactance to electrical current. Our objective was to study the effect BIA-guided versus clinical-guided ultrafiltration on various cardiovascular disease risk factors and markers in HD patients.
  
  
  METHODS
  We included 135 HD patients from a single center in a prospective study, aiming to compare the long-term (12 months) effect of BIA-based versus clinical-based assessment of dry weight on blood pressure (BP), pulse wave velocity (PWV), and serum N-terminal fragment of B-type natriuretic peptide (NT-proBNP). The body composition was measured using the portable whole-body multifrequency BIA device, Body Composition Monitor-BCM(®) (Fresenius Medical Care, Bad Homburg, Germany).
  
  
  RESULTS
  In the "clinical" group there were no changes in BP, body mass index (BMI), and body fluids. The PWV increased from 7.9 ± 2.5 to 9.2 ± 3.6 m/s (P = 0.002), whereas serum NT-proBNP decreased from 5,238 to 3,883 pg/ml (P = 0.05). In the "BIA" group, BMI and body volumes also did not change; however, there was a significant decrease in both systolic BP, from 144.6 ± 14.7 to 135.3 ± 17.8 mmHg (P < 0.001), and diastolic BP, from 79.5 ± 9.7 to 73.2 ± 11.1 mmHg (P < 0.001). In this group, PWV also decreased from 8.2 ± 2.3 to 6.9 ± 2.3 m/s (P = 0.001) and NT-proBNP decreased from 7,552 to 4,561 pg/ml (P = 0.001).
  
  
  CONCLUSIONS
  BIA is not inferior and possibly even better than clinical criteria for assessing dry weight and guiding ultrafiltration in HD patients.
authors.affiliation: University of Medicine and Pharmacy "Gr. T. Popa", Iaşi, Romania.
authors.forename: Mihai
authors.initials: M
authors.lastname: Onofriescu
authors.forename: Nicoleta Genoveva
authors.initials: NG
authors.lastname: Mardare
authors.forename: Liviu
authors.initials: L
authors.lastname: Segall
authors.forename: Luminiţa
authors.initials: L
authors.lastname: Voroneanu
authors.forename: Claudiu
authors.initials: C
authors.lastname: Cuşai
authors.forename: Simona
authors.initials: S
authors.lastname: Hogaş
authors.forename: Serban
authors.initials: S
authors.lastname: Ardeleanu
authors.forename: Ionuţ
authors.initials: I
authors.lastname: Nistor
authors.forename: Octavian Viorel
authors.initials: OV
authors.lastname: Prisadă
authors.forename: Radu
authors.initials: R
authors.lastname: Sascău
authors.forename: Adrian
authors.initials: A
authors.lastname: Covic
mesh_terms: D001794:Blood Pressure / Q000502:physiology*; D015992:Body Mass Index; D001834:Body Water / Q000502:physiology*; D002318:Cardiovascular Diseases / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control; D017097:Electric Impedance; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D011379:Prognosis; D011446:Prospective Studies; D006435:Renal Dialysis / Q000379:methods*; D013997:Time Factors; D016896:Treatment Outcome; D014462:Ultrafiltration; D059289:Vascular Stiffness / Q000502:physiology*
chemical_list: D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain