title: Effects of six versus three times per week hemodialysis on physical performance, health, and functioning: Frequent Hemodialysis Network (FHN) randomized trials.
abstract: OBJECTIVE
  Relatively little is known about the effects of hemodialysis frequency on the disability of patients with ESRD.
  
  
  METHODS
  This study examined changes in physical performance and self-reported physical health and functioning among subjects randomized to frequent (six times per week) compared with conventional (three times per week) hemodialysis in both the Frequent Hemodialysis Network daily (n=245) and nocturnal (n=87) trials. The main outcome measures were adjusted change in scores over 12 months on the short physical performance battery (SPPB), RAND 36-item health survey physical health composite (PHC), and physical functioning subscale (PF) based on the intention to treat principle.
  
  
  RESULTS
  Overall scores for SPPB, PHC, and PF were poor relative to population norms and in line with other studies in ESRD. In the Daily Trial, subjects randomized to frequent compared with conventional in-center hemodialysis experienced no significant change in SPPB (adjusted mean change of -0.20±0.19 versus -0.41±0.21, P=0.45) but experienced significant improvement in PHC (3.4±0.8 versus 0.4±0.8, P=0.009) and a relatively large change in PF that did not reach statistical significance. In the Nocturnal Trial, there were no significant differences among subjects randomized to frequent compared with conventional hemodialysis in SPPB (adjusted mean change of -0.92±0.44 versus -0.41±0.43, P=0.41), PHC (2.7±1.4 versus 2.1±1.5, P=0.75), or PF (-3.1±3.5 versus 1.1±3.6, P=0.40).
  
  
  CONCLUSIONS
  Frequent in-center hemodialysis compared with conventional in-center hemodialysis improved self-reported physical health and functioning but had no significant effect on objective physical performance. There were no significant effects of frequent nocturnal hemodialysis on the same physical metrics.
authors.affiliation: Kidney Research Institute, University of Washington, Seattle, Washington 98108, USA. ynhall@u.washington.edu
authors.forename: Yoshio N
authors.initials: YN
authors.lastname: Hall
authors.forename: Brett
authors.initials: B
authors.lastname: Larive
authors.forename: Patricia
authors.initials: P
authors.lastname: Painter
authors.forename: George A
authors.initials: GA
authors.lastname: Kaysen
authors.forename: Robert M
authors.initials: RM
authors.lastname: Lindsay
authors.forename: Allen R
authors.initials: AR
authors.lastname: Nissenson
authors.forename: Mark L
authors.initials: ML
authors.lastname: Unruh
authors.forename: Michael V
authors.initials: MV
authors.lastname: Rocco
authors.forename: Glenn M
authors.initials: GM
authors.lastname: Chertow
mesh_terms: D000328:Adult; D000368:Aged; D005080:Exercise Test; D005260:Female; D006304:Health Status; D006437:Hemodialysis, Home / Q000379:methods; D006801:Humans; D007676:Kidney Failure, Chronic / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010809:Physical Fitness; D011788:Quality of Life; D006435:Renal Dialysis / Q000379:methods*; D057566:Self Report; D011795:Surveys and Questionnaires