title: Blood pressure and survival in long-term hemodialysis patients with and without polycystic kidney disease.
abstract: BACKGROUND
  In maintenance dialysis patients, low blood pressure (BP) values are associated with higher death rates when compared with normal to moderately high values. This 'hypertension paradox' may be related to comorbid conditions. Dialysis patients with polycystic kidney disease (PKD) usually have a lower comorbidity burden and greater survival. We hypothesized that in PKD dialysis patients, a representative of a healthier dialysis patient population, high BP is associated with higher mortality.
  
  
  METHODS
  Time-dependent survival models including after multivariate adjustment were examined to assess the association between prehemodialysis and posthemodialysis BP and all-cause mortality in a 5-year cohort of 67 085 non-PKD and 1579 PKD hemodialysis patients.
  
  
  RESULTS
  In PKD patients, low prehemodialysis and posthemodialysis SBPs were associated with increased mortality, whereas high prehemodialysis DBP was associated with greater survival. Fully adjusted death hazard ratios (and 95% confidence levels) for prehemodialysis and posthemodialysis BP of less than 120 mmHg (reference 140 to <160 mmHg) were 1.30 (1.06-1.92) and 1.45 (1.04-2.02), respectively, and for prehemodialysis DBP of 80 mmHg or more (reference 70 to <80 mmHg) was 0.68 (0.49-0.93, all P values <0.05). Similar associations were observed in non-PKD patients. In pooled analyses, within each commensurate BP stratum, PKD patients exhibited superior survival to non-PKD patients.
  
  
  CONCLUSIONS
  Among hemodialysis patients, those with PKD display a similar BP paradox as those without PKD, even though within each BP category PKD patients maintain superior survival. Randomized clinical trials are needed to define optimal blood pressure targets in the hemodialysis population.
authors: Harold Simmons Center for Chronic Disease Research & Epidemiology, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, California, USA.
authors: Miklos Z
authors: MZ
authors: Molnar
authors: Lilia R
authors: LR
authors: Lukowsky
authors: Elani
authors: E
authors: Streja
authors: Ramanath
authors: R
authors: Dukkipati
authors: Jennie
authors: J
authors: Jing
authors: Allen R
authors: AR
authors: Nissenson
authors: Csaba P
authors: CP
authors: Kovesdy
authors: Kamyar
authors: K
authors: Kalantar-Zadeh
mesh_terms: D001794:Blood Pressure; D016022:Case-Control Studies; D015331:Cohort Studies; D006801:Humans; D007690:Polycystic Kidney Diseases / Q000503:physiopathology*; D006435:Renal Dialysis; D016019:Survival Analysis