Cognitive Impairment in Hemodialysis Patients: The Frequent Hemodialysis Network

[okarol]

Published ahead of print on July 15, 2010
Clinical Journal of the American Society of Nephrology
© 2010 American Society of Nephrology
doi: 10.2215/CJN.01090210

Prevalence and Correlates of Cognitive Impairment in Hemodialysis Patients: The Frequent Hemodialysis Network Trials
Manjula Kurella Tamura*,{dagger}, Brett Larive{ddagger}, Mark L. Unruh§, John B. Stokes||, Allen Nissenson¶, Ravindra L. Mehta**, Glenn M. Chertow*, and for the Frequent Hemodialysis Network Trial Group

* Division of Nephrology, Stanford University School of Medicine, Palo Alto, California; {dagger} VA Palo Alto Health Care System Geriatrics Research Education and Clinical Center, Palo Alto, California; {ddagger} Department of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, Ohio; § Renal-Electrolyte Division, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania; || Division of Nephrology, University of Iowa, and VA Medical Center, Iowa City, Iowa; ¶ Division of Nephrology, University of California Los Angeles, Los Angeles, California; and ** Division of Nephrology and Hypertension, University of California San Diego, San Diego, California

Correspondence: Dr. Manjula Kurella Tamura, Division of Nephrology, Stanford University, 780 Welch Road, Suite 106 Palo Alto, CA 94304. Phone: 650-721-6617; Fax: 650-721-1443; E-mail: mktamura@stanford.edu

Background and objectives: 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.

Design, setting, participants, & measurements: 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 ≥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.

http://cjasn.asnjournals.org/cgi/content/abstract/CJN.01090210v2