Prevalence and correlates of cognitive impairment in hemodialysis patients: the Frequent Hemodialysis Network trials.
OBJECTIVE
Cognitive impairment is common among persons with ESRD, but the underlying mechanisms are unknown. This study evaluated the prevalence of cognitive impairment and association with modifiable ESRD- and dialysis-associated factors in a large group of hemodialysis patients.


METHODS
Cross-sectional analyses were conducted on baseline data collected from 383 subjects participating in the Frequent Hemodialysis Network trials. Global cognitive impairment was defined as a score <80 on the Modified Mini-Mental State Exam, and impaired executive function was defined as a score >or=300 seconds on the Trailmaking B test. Five main categories of explanatory variables were examined: urea clearance, nutritional markers, hemodynamic measures, anemia, and central nervous system (CNS)-active medications.


RESULTS
Subjects had a mean age of 51.6 +/- 13.3 years and a median ESRD vintage of 2.6 years. Sixty-one subjects (16%) had global cognitive impairment, and 110 subjects (29%) had impaired executive function. In addition to several nonmodifiable factors, the use of H1-receptor antagonists and opioids were associated with impaired executive function. No strong association was found between several other potentially modifiable factors associated with ESRD and dialysis therapy, such as urea clearance, proxies of dietary protein intake and other nutritional markers, hemodynamic measures, and anemia with global cognition and executive function after adjustment for case-mix factors.


CONCLUSIONS
Cognitive impairment, especially impaired executive function, is common among hemodialysis patients, but with the exception of CNS-active medications, is not strongly associated with several ESRD- and dialysis-associated factors.
Kurella Tamura
Manjula
M
Division of Nephrology, Stanford University School of Medicine, Palo Alto, California 94304, USA. mktamura@stanford.edu
Larive
Brett
B
Unruh
Mark L
ML
Stokes
John B
JB
Nissenson
Allen
A
Mehta
Ravindra L
RL
Chertow
Glenn M
GM
D000328:Adult; D000368:Aged; D000701:Analgesics, Opioid / Q000009:adverse effects; D002170:Canada / Q000453:epidemiology; D003071:Cognition; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology* / Q000523:psychology; D003430:Cross-Sectional Studies; D056344:Executive Function; D006634:Histamine H1 Antagonists / Q000009:adverse effects; D006801:Humans; D007676:Kidney Failure, Chronic / Q000453:epidemiology / Q000523:psychology / Q000628:therapy*; D016015:Logistic Models; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D016017:Odds Ratio; D015995:Prevalence; D011569:Psychiatric Status Rating Scales; D016032:Randomized Controlled Trials as Topic; D006435:Renal Dialysis / Q000009:adverse effects / Q000523:psychology; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology
D000701:Analgesics, Opioid; D006634:Histamine H1 Antagonists