Laptop-Administered NIH Toolbox and Cogstate Brief Battery in Community-Dwelling Black Adults: Unexpected Pattern of Cognitive Performance between MCI and Healthy Controls

Construct validation of NIH Toolbox Cognition Battery premorbid cognitive functioning scores in Black and White older Americans with and without mild cognitive impairment

OBJECTIVE

Valid estimates of premorbid cognitive functioning (PMIQ) are crucial for the assessment of older adults at risk for Alzheimer's disease. We investigated the relationship between the NIH Toolbox-Cognition Battery's (NIHTB-CB) Oral Reading Recognition (ORR) subtest and Wechsler Test of Adult Reading scores (WTAR, convergent validity). We also compared ORR to NIHTB-CB Flanker scores, where null relationships were expected (discriminant validity).

METHODS

The WTAR and NIHTB-CB were administered to 130 cognitively normal (CN) and 113 participants with mild cognitive impairment (MCI). Participants were community-dwelling, older Black and White adults, ages 55-88 years. Data analysis used uncorrected standard scores and Bayesian bivariate correlations. Supplemental materials include intraclass correlations.

RESULTS

ORR and WTAR scores were strongly positively associated, while ORR and Flanker scores were unrelated. This pattern held when restricting analyses to the two cognitive status groups, the two racial groups, and the four race-by-diagnosis subgroups.

CONCLUSION

The findings demonstrate convergent and discriminant validity and support NIHTB-CB ORR scores as valid estimates of scores on a PMIQ measure in older Black and White adults with and without MCI.

Using Objective Vision Measures to Explore the Association of Vision Impairment With Cognition Among Older Adults in the United States

PURPOSE

To evaluate the association between vision impairment (VI) and cognitive function using objective measures.

DESIGN

Cross-sectional analysis with a nationally representative sample.

METHODS

The association between VI and dementia was investigated in a US population-based, nationally representative sample of Medicare beneficiaries, the National Health and Aging Trends Study (NHATS), a nationally representative sample of Medicare beneficiaries aged ≥65 years, using objective vision measures. Exposures included distance VI (>20/40), near VI (>20/40), contrast sensitivity impairment (CSI) (<1.55), any objective VI (distance and near visual acuity, or contrast), and self-reported VI. The main outcome measure was dementia status defined based on survey reports, interviews, and cognitive tests.

RESULTS

A total of 3026 adults were included in this study; the majority were female (55%) and White (82%). The weighted prevalence rates were 10% for distance VI, 22% for near VI, 22% for CSI, 34% for any objective VI, and 7% for self-reported VI. Across all measures of VI, dementia was more than twice as prevalent in adults with VI compared to their peers without (P < .001 for all). In adjusted models, all measures of VI were associated with higher odds of dementia (distance VI: OR 1.74, 95% CI 1.24-2.44; near VI: OR 1.68, 95% CI 1.29-2.18; CSI: OR 1.95, 95% CI 1.45-2.62; any objective VI: OR 1.83, 95% CI 1.43-2.35; self-reported VI: OR 1.86, 95% CI 1.20-2.89).

CONCLUSIONS

In a nationally representative sample of older US adults, VI was associated with increased odds of dementia. These results suggest that maintaining good vision and eye health may help preserve cognitive function in older age, although more research is needed to investigate the potential benefits of interventions that focus on vision and eye health on cognitive outcomes.

Mild Cognitive Impairment Subtype Performance in Comparison to Healthy Older Controls on the NIH Toolbox and Cogstate

BACKGROUND

Early detection is necessary for the treatment of dementia. Computerized testing has become more widely used in clinical trials; however, it is unclear how sensitive these measures are to early signs of neurodegeneration. We investigated the use of the NIH Toolbox-Cognition (NIHTB-CB) and Cogstate-Brief computerized neuropsychological batteries in the identification of mild cognitive impairment (MCI) versus healthy older adults [healthy control (HC)] and amnestic (aMCI) versus nonamnestic MCI (naMCI). Exploratory analyses include investigating potential racial differences.

METHODS

Two hundred six older adults were diagnosed as aMCI (n = 58), naMCI (n = 15), or cognitively healthy (HC; n = 133).

RESULTS

The NIH Toolbox-CB subtests of Flanker, Picture Sequence Memory, and Picture Vocabulary significantly differentiated MCI from HC. Further, subtests from both computerized batteries differentiated patients with aMCI from those with naMCI. Although the main effect of race differences was noted on tests and in diagnostic groups was significant, there were no significant race-by-test interactions.

CONCLUSIONS

Computer-based subtests vary in their ability to help distinguish MCI subtypes, though these tests provide less expensive and easier-to-administer clinical screeners to help identify patients early who may qualify for more comprehensive evaluations. Further work is needed, however, to refine computerized tests to achieve better precision in distinguishing impairment subtypes.

A Paradox in Digital Memory Assessment: Increased Sensitivity With Reduced Difficulty

The One Card Learning Test (OCL80) from the Cogstate Brief Battery-a digital cognitive test used both in-person and remotely in clinical trials and in healthcare contexts to inform health decisions-has shown high sensitivity to changes in memory in early Alzheimer's disease (AD). However, recent studies suggest that OCL sensitivity to memory impairment in symptomatic AD is not as strong as that for other standardized assessments of memory. This study aimed to improve the sensitivity of the OCL80 to AD-related memory impairment by reducing the test difficultly (i.e., OCL48). Experiment 1 showed performance in healthy adults improved on the OCL48 while the pattern separation operations that constrain performance on the OCL80 were retained. Experiment 2 showed repeated administration of the OCL48 at short retest intervals did not induce ceiling or practice effects. Experiment 3 showed that the sensitivity of the OCL48 to AD-related memory impairment (Glass's Δ = 3.11) was much greater than the sensitivity of the OCL80 (Glass's Δ = 1.94). Experiment 4 used data from a large group of cognitively normal older adults to calibrate performance scores between the OCL80 and OCL48 using equipercentile equating. Together these results showed the OCL48 to be a valid and reliable test of learning with greater sensitivity to memory impairment in AD than the OCL80.