title: Cognitive function and dialysis adequacy: no clear relationship.
abstract: OBJECTIVE
  Cognitive impairment is common in hemodialysis patients and may be impacted by multiple patient and treatment characteristics. The impact of dialysis dose on cognitive function remains uncertain, particularly in the current era of increased dialysis dose and flux.
  
  
  METHODS
  We explored the cross-sectional relationship between dialysis adequacy and cognitive function in a cohort of maintenance hemodialysis patients. Adequacy was defined as the average of the 3 most proximate single pool Kt/V assessments. A detailed neurocognitive battery was administered during the 1st hour of dialysis. Multivariable linear regression models were adjusted for age, sex, education, race and other clinical and demographic characteristics.
  
  
  RESULTS
  Among 273 patients who underwent cognitive testing, the mean (SD) age was 63 (17) years and the median dialysis duration was 13 months, 47% were woman, 22% were African American, and 48% had diabetes. The mean (SD) Kt/V was 1.51 (0.24). In univariate, parsimonious and multivariable models, there were no significant relationships between decreased cognitive function and lower Kt/V.
  
  
  CONCLUSIONS
  In contrast to several older studies, there is no association between lower Kt/V and worse cognitive performance in the current era of increased dialysis dose. Future studies should address the longitudinal relationship between adequacy of dialysis and cognitive function to confirm these findings.
authors.affiliation: Tufts Medical Center, Boston, MA 02111, USA.
authors.forename: Lena M
authors.initials: LM
authors.lastname: Giang
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Weiner
authors.forename: Brian T
authors.initials: BT
authors.lastname: Agganis
authors.forename: Tammy
authors.initials: T
authors.lastname: Scott
authors.forename: Eric P
authors.initials: EP
authors.lastname: Sorensen
authors.forename: Hocine
authors.initials: H
authors.lastname: Tighiouart
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Sarnak
mesh_terms: D000368:Aged; D003071:Cognition; D003072:Cognition Disorders / Q000150:complications / Q000175:diagnosis; D003430:Cross-Sectional Studies; D005006:Ethnicity; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000175:diagnosis / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D012044:Regression Analysis; D006435:Renal Dialysis / Q000379:methods*; D016896:Treatment Outcome