Diagnostic Sensitivity and Specificity of Cognitive Tests for Mild Cognitive Impairment and Alzheimer's Disease in Patients With Down Syndrome: A Systematic Review and Meta-Analysis
Journal of Alzheimer's Disease
Nadeau, P. A., Jobin, B., et al. (2023).
Journal of Alzheimer's Disease, 95(1), 13-51.
<div>This systematic review with meta-analysis investigates the psychometric properties of cognitive assessment tools for adults, 18 years and older, with mild cognitive impairment (MCI) or Alzheimer's disease and Down syndrome (DS).</div>
Canadian Institute of Health Research; Institut Universitaire de Gériatrie de Montréal (Canada)
2000 to May 30, 2023
<div>Published studies with a control group</div>
81 studies included in the systematic review. 12 studies included in the meta-analysis
<div>Several cognitive assessment tools demonstrated potential for detecting Alzheimer's disease (AD) in individuals with Down syndrome. Findings regarding individual tools include the following:</div>
<ul>
<li>The Down Syndrome Mental State Examination presented a floor effect and low sensitivity.</li>
<li>The Severe Impairment Battery showed a sensitivity of 0.66 and a specificity of 0.66 in one study.</li>
<li>The Cambridge Cognitive Examination adapted for individuals with Down Syndrome (CAMCOG-DS) presented greater diagnostic accuracy for identifying AD in individuals with moderate intellectual disability (ID; sensitivity=89.6%, specificity=75.2%) compared to individuals with mild ID (sensivity=71.4%, specificity=88.9%).</li>
<li>The Cued recall text demonstrated sensitivity ranging from 0.75 to 0.99 and specificity ranging from 0.75 to 0.99.</li>
</ul>
<div>The authors identified other assessment tools and screening tasks that demonstrated promise including:</div>
<ul>
<li>the Selective Reminding test;</li>
<li>the Verbal Fluency test;</li>
<li>the Tower of London;</li>
<li>the Cats and Dogs Stroop test; and</li>
<li>the Brief Praxis test.</li>
</ul>
<div>Limitations of this review include the variability in diagnostic criteria used for participants, the exclusion of participants with severe and profound intellectual disability (ID), the heterogeneity of participant age across studies, and the limited availability of data sets. Additional research is needed to investigate individuals with severe and profound ID using standardized diagnostic criteria and improved data reporting.</div>
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<div>For detecting MCI, the Cambridge Cognitive Examination adapted for individuals with Down Syndrome (CAMCOG-DS) demonstrated good diagnostic accuracy for individuals with mild intellectual disability (ID; sensitivity=77.6%, specificity=78.8%) and poor accuracy for individuals with moderate ID (sensitivity=65.6%, specificity=56.2%). The Cued recall test showed promising accuracy with sensitivity ranging from 0.60 to 0.70 and specificity ranging from 0.73 to 0.79. The Severe impairment battery failed to demonstrate sufficient sensitivity or specificity for identifying MCI in individuals with Down syndrome.</div>
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<div>Limitations of this review include the variability in diagnostic criteria used for participants, the exclusion of participants with severe and profound intellectual disability (ID), the heterogeneity of participant age across studies, and the limited availability of data sets. Additional research is needed to investigate individuals with severe and profound ID using standardized diagnostic criteria and improved data reporting.</div>
