title: The Montreal Cognitive Assessment (MoCA) - a sensitive screening instrument for detecting cognitive impairment in chronic hemodialysis patients.
abstract: BACKGROUND
  Chronic kidney disease (CKD) patients undergoing hemodialysis (HD) therapy have an increased risk of developing cognitive impairment and dementia, which are known relevant factors in disease prognosis and therapeutic success, but still lack adequate screening in clinical routine. We evaluated the Montreal Cognitive Assessment (MoCA) for suitability in assessing cognitive performance in HD patients in comparison to the commonly used Mini-Mental State Examination (MMSE) and a detailed neuropsychological test battery, used as gold standard.
  
  
  METHODS
  43 HD patients and 42 healthy controls with an average age of 58 years, were assessed with the MoCA, the MMSE and a detailed neuropsychological test battery, covering the domains of memory, attention, language, visuospatial and executive functions. Composite scores were created for comparison of cognitive domains and test results were analyzed using Spearman's correlation and linear regression. Cognitive dysfunction was defined using z-score values and predictive values were calculated. Sensitivity and specificity of the MoCA were determined using receiver operating characteristic (ROC) analysis.
  
  
  RESULTS
  HD patients performed worse in all cognitive domains, especially in memory recall and executive functions. The MoCA correlated well with the detailed test battery and identified patients with cognitive impairment with a sensitivity of 76.7% and specificity of 78.6% for a cut-off value of ≤24 out of 30 points. In the detailed assessment executive functions accounted significantly for performance in the MoCA. The MMSE only discriminated weakly between groups.
  
  
  CONCLUSIONS
  The MoCA represents a suitable cognitive screening tool for hemodialysis patients, demonstrating good sensitivity and specificity levels, and covering executive functions, which appear to play an important role in cognitive performance of HD patients.
authors.affiliation: Department of Neurology, RWTH Aachen University Hospital, Aachen, Germany; Jülich Aachen Research Alliance (JARA) - Translational Brain Medicine, Aachen and Jülich, Germany.
authors.forename: Frances E
authors.initials: FE
authors.lastname: Tiffin-Richards
authors.affiliation: Department of Neurology, RWTH Aachen University Hospital, Aachen, Germany; Jülich Aachen Research Alliance (JARA) - Translational Brain Medicine, Aachen and Jülich, Germany.
authors.forename: Ana S
authors.initials: AS
authors.lastname: Costa
authors.affiliation: KfH Curatorship for Dialysis and Kidney Transplant e.V., KfH-Nephrology Center, Stolberg, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Holschbach
authors.affiliation: Department of Internal Medicine, St.-Antonius-Hospital Eschweiler, Eschweiler, Germany.
authors.forename: Rolf D
authors.initials: RD
authors.lastname: Frank
authors.affiliation: Dialysis Center Aachen, Dialysis Center, Aachen, Germany.
authors.forename: Athina
authors.initials: A
authors.lastname: Vassiliadou
authors.affiliation: Division of Nephrology and Clinical Immunology, RWTH Aachen University, Aachen, Germany.
authors.forename: Thilo
authors.initials: T
authors.lastname: Krüger
authors.affiliation: Department of Neurology, RWTH Aachen University Hospital, Aachen, Germany; Jülich Aachen Research Alliance (JARA) - Translational Brain Medicine, Aachen and Jülich, Germany.
authors.forename: Karl
authors.initials: K
authors.lastname: Kuckuck
authors.affiliation: Division of Nephrology and Clinical Immunology, RWTH Aachen University, Aachen, Germany; Department of Internal Medicine, Dresden-Friedreichstadt Hospital, Dresden, Germany.
authors.forename: Theresa
authors.initials: T
authors.lastname: Gross
authors.affiliation: Division of Nephrology and Clinical Immunology, RWTH Aachen University, Aachen, Germany; Bayer Pharma AG, Global Drug Development, Kidney Diseases Research, Wuppertal, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Eitner
authors.affiliation: Division of Nephrology and Clinical Immunology, RWTH Aachen University, Aachen, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Floege
authors.affiliation: Department of Neurology, RWTH Aachen University Hospital, Aachen, Germany; Jülich Aachen Research Alliance (JARA) - Translational Brain Medicine, Aachen and Jülich, Germany.
authors.forename: Jörg B
authors.initials: JB
authors.lastname: Schulz
authors.affiliation: Department of Neurology, RWTH Aachen University Hospital, Aachen, Germany; Jülich Aachen Research Alliance (JARA) - Translational Brain Medicine, Aachen and Jülich, Germany; Institute of Neuroscience and Medicine (INM-4), Research Center Jülich GmbH, Jülich, Germany.
authors.forename: Kathrin
authors.initials: K
authors.lastname: Reetz
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D060825:Cognitive Dysfunction / Q000175:diagnosis* / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D012372:ROC Curve; D006435:Renal Dialysis / Q000009:adverse effects*; D051436:Renal Insufficiency, Chronic / Q000150:complications / Q000628:therapy; D013647:Task Performance and Analysis