The Montreal Cognitive Assessment (MoCA) - a sensitive screening instrument for detecting cognitive impairment in chronic hemodialysis patients

PLoS One. 2014 Oct 27;9(10):e106700. doi: 10.1371/journal.pone.0106700. eCollection 2014.


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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Case-Control Studies
  • Cognitive Dysfunction / diagnosis*
  • Cognitive Dysfunction / etiology*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Neuropsychological Tests
  • ROC Curve
  • Renal Dialysis / adverse effects*
  • Renal Insufficiency, Chronic / complications
  • Renal Insufficiency, Chronic / therapy
  • Task Performance and Analysis

Grant support

Ana S. Costa was supported by a PhD fellowship (SFRH/BD/65743/2009) from Fundação para a Ciência e Tecnologia (FCT, Portugal) and financed by the POPH – QREN Program. Kathrin Reetz was funded by the Excellence Initiative of the German federal and state governments (DFG ZUK32/1). Jörg B. Schulz was in part funded by the Helmholtz Alliance ICEMED - Imaging and Curing Environmental Metabolic Diseases, through the Initiative and Network Fund of the Helmholtz Association. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.