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Neuropsychological Test Norms in Cognitively Intact Oldest-Old

  • Zarui A. Melikyan (a1), Maria M. Corrada (a1) (a2) (a3), Malcolm B. Dick (a1), Christina Whittle (a1), Annlia Paganini-Hill (a2) and Claudia H. Kawas (a1) (a2) (a4)...

Abstract

Objectives: Individuals aged 90 or older (oldest-old), the fastest growing segment of the population, are at increased risk of developing cognitive impairment compared with younger old. Neuropsychological evaluation of the oldest-old is important yet challenging in part because of the scarcity of test norms for this group. We provide neuropsychological test norms for cognitively intact oldest-old. Methods: Test norms were derived from 403 cognitively intact participants of The 90+ Study, an ongoing study of aging and dementia in the oldest-old. Cognitive status of intact oldest-old was determined at baseline using cross-sectional approach. Individuals with cognitive impairment no dementia or dementia (according to DSM-IV criteria) were excluded. Participants ranged in age from 90 to 102 years (mean=94). The neuropsychological battery included 11 tests (Mini-Mental Status Examination, Modified Mini-Mental State Examination, Boston Naming Test – Short Form, Letter Fluency Test, Animal Fluency Test, California Verbal Learning Test-II Short Form, Trail Making Tests A/B/C, Digit Span Forward and Backwards Test, Clock Drawing Test, CERAD Construction Subtests), and the Geriatric Depression Scale. Results: Data show significantly lower scores with increasing age on most tests. Education level, sex, and symptoms of depression were associated with performance on several tests after accounting for age. Conclusions: Provided test norms will help to distinguish cognitively intact oldest-old from those with cognitive impairment. (JINS, 2019, 25, 530–545)

Copyright

Corresponding author

Correspondence and reprint requests to: Zarui A. Melikyan, 1511 Hewitt Hall, 843 Health Sciences Road, Irvine, CA 92697. E-mail: zmelikya@uci.edu

References

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