title: Extracellular fluid management and hypertension in urban dwelling versus rural dwelling hemodialysis patients.
abstract: Rural-dwelling hemodialysis patients have less frequent contact with nephrologists than urban-dwelling patients, and are known to have higher mortality. We hypothesized that rural-dwelling hemodialysis patients would have more evidence of poorly controlled extracellular fluid volume (ECVF) than otherwise similar urban-dwellers.
  
  
  
  We studied prevalent hemodialysis patients within a single renal program in Alberta, Canada and assessed ECFV using bioimpedance spectroscopy (BIS). Our primary outcome was impedance vector length (ohm/m) as assessed by BIS using the Xitron Hydra 4200 device, where shorter vector length indicated poorer ECFV control. Because poor ECFV control can lead to hypertension, we also assessed pre- and post-dialysis blood pressure. We measured outcomes at baseline.
  
  
  
  We studied 228 hemodialysis patients, of whom 115 (50.4 %) and 113 (49.6 %) were urban- and rural-dwelling, respectively. There were no differences in volume control in urban versus rural participants; odds ratio (OR) for vector length in the lowest sex-specific quartile of vector length was 0.93 (95 % CI 0.54, 1.59) after adjusting for age, sex, diabetic status, years since dialysis initiation and phase angle. The odds of very poor blood pressure control (pre-dialysis blood pressure ≥180/100) did not differ between urban and rural participants [fully adjusted OR 0.96 (0.36, 2.60)].
  
  
  
  Differences in ECFV control do not appear to explain higher mortality among remote- and rural- dwelling hemodialysis patients, compared to urban-dwellers.
authors.affiliation: University of Calgary, 7th Floor, TRW Building, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada. tonelli.admin@ucalgary.ca.
authors.forename: Marcello
authors.initials: M
authors.lastname: Tonelli
authors.affiliation: University of Calgary, 7th Floor, TRW Building, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada.
authors.forename: Anita
authors.initials: A
authors.lastname: Lloyd
authors.affiliation: University of Calgary, 7th Floor, TRW Building, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada.
authors.forename: Neesh
authors.initials: N
authors.lastname: Pannu
authors.affiliation: University of Calgary, 7th Floor, TRW Building, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada.
authors.forename: Scott
authors.initials: S
authors.lastname: Klarenbach
authors.affiliation: University of Calgary, 7th Floor, TRW Building, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada.
authors.forename: Pietro
authors.initials: P
authors.lastname: Ravani
authors.affiliation: University of Calgary, 7th Floor, TRW Building, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada.
authors.forename: Kailash
authors.initials: K
authors.lastname: Jindal
authors.affiliation: University of Calgary, 7th Floor, TRW Building, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada.
authors.forename: Jennifer
authors.initials: J
authors.lastname: MacRae
authors.affiliation: University of Calgary, 7th Floor, TRW Building, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada.
authors.forename: Larry
authors.initials: L
authors.lastname: Unsworth
authors.affiliation: University of Calgary, 7th Floor, TRW Building, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada.
authors.forename: Braden
authors.initials: B
authors.lastname: Manns
authors.affiliation: University of Calgary, 7th Floor, TRW Building, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada.
authors.forename: Brenda
authors.initials: B
authors.lastname: Hemmelgarn
mesh_terms: D000328:Adult; D000368:Aged; D000416:Alberta / Q000453:epidemiology; D001794:Blood Pressure; D001823:Body Composition; D017097:Electric Impedance; D045604:Extracellular Fluid; D005260:Female; D018495:Fluid Shifts; D006801:Humans; D006973:Hypertension / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology*; D007668:Kidney / Q000503:physiopathology*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D015995:Prevalence; D006435:Renal Dialysis / Q000009:adverse effects; D051436:Renal Insufficiency, Chronic / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D012307:Risk Factors; D012423:Rural Health; D013057:Spectrum Analysis / Q000379:methods; D013997:Time Factors; D016896:Treatment Outcome; D014504:Urban Health
keywords: Bioimpedance; Extracellular fluid volume control; Hemodialysis; Rural-dwelling; Vector length