Brief cognitive tests as a decision-making tool in primary care. A population and validation study

Area of Science:

• Gerontology
• Neurology
• Primary Care Medicine

Background:

• Brief cognitive tests (BCT) are crucial for detecting cognitive impairment (CI) in primary care settings.
• Limited data exists on the diagnostic utility (DU) of BCT in community-based populations.
• This study addresses the need for population-level DU data for BCT in early CI detection.

Purpose of the Study:

• To evaluate the diagnostic utility of Fototest, T@M, AD8 questionnaire, and Mini-Mental State Examination (MMSE) at the population level.
• To establish new, validated cut-off points (CoP) for these BCT within an early CI detection program.
• To assess the effectiveness of BCT in identifying cognitive impairment in a community setting.

Main Methods:

• A two-phase evaluation was conducted: initial screening with BCT, followed by blinded clinical diagnosis using NIA-AA criteria.
• Diagnostic utility was assessed using the area under the ROC curve (aROC) in the population sample.
• Optimal CoP were determined using the Youden index, prioritizing specificity while ensuring at least 80% sensitivity.

Main Results:

• The study included 260 participants in the population sample (23.1% with CI) and 177 in the validation sample (42.4% with CI).
• Fototest demonstrated the highest diagnostic utility at the population level (aROC 0.851), which improved to 0.875 when combined with the AD8 questionnaire.
• Proposed cut-off points are AD8 ≥ 1, Fototest ≤ 35, T@M ≤ 40, and MMSE ≤ 26.

Conclusions:

• Brief cognitive tests are valuable tools for detecting cognitive impairment in primary care.
• The findings support the implementation of more rigorous BCT, like Fototest and AD8, for enhanced early CI detection.
• Validated cut-off points improve the reliability of BCT in community settings.