Design and baseline characteristics of the Cognitive and Aerobic Resilience for the Brain (CARB) study.

BACKGROUND: Treatments that delay progression of cognitive impairment in older adults are of great public health significance. This manuscript outlines the protocol, recruitment, baseline characteristics, and retention for a randomized controlled trial of cognitive and aerobic physical training to improve cognition in individuals with subjective cognitive dysfunction, the "Cognitive and Aerobic Resilience for the Brain" (CARB) study. METHODS: Community-dwelling, older adults with self-reported memory loss were randomly assigned to receive either computer-based cognitive training, aerobic physical training, combined cognitive and physical training, or education control. Treatment was delivered 2- to 3-times per week in 45- to 90-min sessions for 12 weeks by trained facilitators videoconferencing into subject's home. Outcome assessments of were taken at the baseline, immediately following training, and 3-months after training. RESULTS: 191 subjects were randomized into the trial (mean age, 75.5 years; 68% female; 20% non-white; mean education, 15.1 years; 30% with 1+ APOE e4 allele). The sample was generally obese, hypertensive, and many were diabetic, while cognition, self-reported mood, and activities of daily living were in the normal range. There was excellent retention throughout the trial. Interventions were completed at high rates, participants found the treatments acceptable and enjoyable, and outcome assessments were completed at high rates. CONCLUSIONS: This study was designed to determine the feasibility of recruiting, intervening, and documenting response to treatment in a population at risk for progressive cognitive decline. Older adults with self-reported memory loss were enrolled in high numbers and were well engaged with the intervention and outcome assessments.

Lessons learned regarding recruitment to the National African American Alzheimer Disease Health Literacy Program.

It has been shown that patients with poor health literacy generally do not fare as well from a health perspective because they lack understanding of health information and are unaware of the steps involved in preventative health care. There are also unique issues with regard to the recruitment of minority participants into research. The National African American Alzheimer Disease Health Literacy Program was a research project whose purpose was to increase the health literacy of African American adults by providing objective scientific and educational information to the African American community of patients, families, and caregivers about dementia and Alzheimer disease. The target audience was the African American communities of Chicago, Cleveland, Indianapolis, Los Angeles, Newark, and Washington D.C. Reaching into these communities for participants was challenging for a variety of reasons and provided insight into potential strategies for working with the population of elderly African Americans. This article discusses the successes and challenges of the work conducted in Indianapolis.

Changes in everyday function in individuals with psychometrically defined mild cognitive impairment in the Advanced Cognitive Training for Independent and Vital Elderly Study.

OBJECTIVES: To examine trajectories of change in everyday function for individuals with cognitive deficits suggestive of mild cognitive impairment (MCI). DESIGN: Using data from the longitudinal, multisite Advanced Cognitive Training for Independent and Vital Elderly Study allowed for post hoc classification of MCI status at baseline using psychometric definitions for amnestic MCI, nonamnestic MCI, multidomain MCI, and no MCI. SETTING: Six U.S. cities. PARTICIPANTS: Two thousand eight hundred thirty-two volunteers (mean age 74; 26% African American) living independently, recruited from senior housing, community centers, hospitals, and clinics. MEASUREMENTS: Mixed-effect models examined changes in self-reported activities of daily living and instrumental activities of daily living (IADLs) from the Minimum Data Set Home Care Interview in 2,358 participants over a 3-year period. RESULTS: In models for IADL performance, IADL difficulty, and a daily functioning composite, there was a significant time by MCI classification interaction for each MCI subtype, indicating that all MCI groups showed faster rates of decline in everyday function than cognitively normal participants with no MCI. CONCLUSION: Results demonstrate the importance of MCI as a clinical entity that not only predicts progression to dementia, but also predicts functional declines in activities that are key to autonomy and quality of life. MCI classification guidelines should allow for functional changes in MCI, and clinicians should monitor for such changes. Preservation of function may serve as a meaningful outcome for intervention efforts.

Relationship of demographic and health factors to cognition in older adults in the ACTIVE study.

OBJECTIVE: Examine the relationship of demographics and health conditions, alone and in combination, on objective measures of cognitive function in a large sample of community-dwelling older adults. METHOD: Baseline data from 2,782 participants in the Advanced Cognitive Training in Independent and Vital Elderly (ACTIVE) study were used to examine relationships of demographics and health conditions with composite scores of memory, reasoning, and speed of processing. RESULTS: Younger age, increased education, and White race were independently associated with better performance in each cognitive domain after adjusting for gender and health conditions. Male gender, diabetes, and suspected clinical depression were associated with poorer cognitive functioning; suspected clinical depression was associated with lower reasoning and diabetes and history of stroke with slower speed of processing. DISCUSSION: Age, education, and race are consistently associated with cognitive performance in this sample of older community-dwelling adults. Diabetes, stroke, and suspected clinical depression had independent but weaker effects on cognition.

Norms for CERAD constructional praxis recall.

Recall of the four-item constructional praxis measure was a later addition to the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuropsychological battery. Norms for this measure, based on cognitively intact African Americans age ≥70 (Indianapolis-Ibadan Dementia Project, N=372), European American participants age ≥66 (Cache County Study of Memory, Health and Aging, N=507), and European American CERAD clinic controls age ≥50 (N = 182), are presented here. Performance varied by site; by sex, education, and age (African Americans in Indianapolis); education and age (Cache County European Americans); and only age (CERAD European American controls). Performance declined with increased age, within age with less education, and was poorer for women. Means, standard deviations, and percentiles are presented separately for each sample.

Effect of memory impairment on training outcomes in ACTIVE.

Cognitive training improves mental abilities in older adults, but the trainability of persons with memory impairment is unclear. We conducted a subgroup analysis of subjects in the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) trial to examine this issue. ACTIVE enrolled 2802 non-demented, community-dwelling adults aged 65 years and older and randomly assigned them to one of four groups: Memory training, reasoning training, speed-of-processing training, or no-contact control. For this study, participants were defined as memory-impaired if baseline Rey Auditory Verbal Learning Test (AVLT) sum recall score was 1.5 SD or more below predicted AVLT sum recall score from a regression-derived formula using age, education, ethnicity, and vocabulary from all subjects at baseline. Assessments were taken at baseline (BL), post-test, first annual (A1), and second annual (A2) follow-up. One hundred and ninety-three subjects were defined as memory-impaired and 2580 were memory-normal. Training gain as a function memory status (impaired vs. normal) was compared in a mixed effects model. Results indicated that memory-impaired participants failed to benefit from Memory training but did show normal training gains after reasoning and speed training. Memory function appears to mediate response to structured cognitive interventions in older adults.