Can a combination of two neuropsychological tests screen for mild neurocognitive disorder better than each test alone? A cross-sectional study

Abstract

Abstract Background Early symptoms of dementia may not be apparent and are sometimes even concealed during short office visits initiated for other complaints. The aim of the study is to find out if the combined use of VF/CDT, VF/BNT, or CDT/BNT could improve the accuracy of detecting mild NCD in an outpatient setting, compared with either test used alone. Participants Community-dwelling older adults, attending the outpatient Geriatrics Clinic at Ain Shams University hospitals between June 1, 2017 and January 31, 2018. All participants received a comprehensive geriatric assessment (CGA) which included the mini-mental state examination test. Participants with a score of less than 24 and fulfil DSM5 criteria for mild neurocognitive disorder (NCD) are considered cognitively impaired otherwise are considered normal. Then participants were further examined by the Arabic versions of CDT, BNT, and VF animal category. Results We recruited 143 male and female participants mean age 67.17 ± 5.41, females are 56.6%, and 48.9% of all participants have mild NCD according to DSM5 criteria. AUC for individual neurocognitive tests in illiterates is 0.893 for clock drawing test, 0.907 for verbal fluency animal category, and 0.904 for Boston naming test, while AUC for neurocognitive test combinations in illiterates is 0.932 for VF + CDT, 0.917 for VF + BNT, and 0.932 for BNT + CDT. On the other hand, AUC for individual neurocognitive tests in educated participants is 0.925 for clock drawing test, 0.921 for verbal fluency animal category, and 0.907 for Boston naming test, whereas AUC for neurocognitive test combinations in educated participants is 0.958 for VF + CDT, 0.963 for VF + BNT, and 0.953 for BNT + CDT. Conclusion From the current study, we can conclude that any of the studied combinations have better diagnostic accuracy (although small) than individual test in both literate and illiterate older adults.

Keywords

• Neuropsychological tests
• Verbal fluency
• Clock drawing test
• Boston naming test
• Neurocognitive disorder
• Arabic CERAD