Abstract Background There is significant attention to the growing elderly African American population and estimating who and how many within this population will be affected by cognitive impairment. ...Objective The etiology of cognitive impairment has not been well studied in African Americans and the contribution of genetic and environmental influences to cognitive impairment is not clear. Methods We calculated concordance rates and heritability for cognitive impairment in 95 same-sexed pairs of African American twins from the Carolina African American Twin Study on Aging (CAATSA). The sample had an average age of 59.6 years ( SD = 8.6 years, range 50-88 years) and 60% were female. The Telephone Interview for Cognitive Status (TICS) was used to assess cognitive impairment with a lower cutoff based on our previous research with African Americans. Results Thirteen of the monozygotic (MZ) twins (30.2%) and 9 of the dizygotic (DZ) twins (17.3%) were cognitively impaired. The concordance rate was 72% for MZ and 45% for DZ. We found the heritability for cognitive impairment to be 54%. Conclusions The study findings indicate that cognitive impairment is highly heritable, suggesting that genetics may play a relatively large role in the development of cognitive impairment in African American twins.
The rates of high blood pressure among African Americans, as a group, are the highest in the world. The implications for higher average blood pressure include complications for many major chronic ...conditions, such as cardiovascular disease and diabetes. Less well studied is the effect of blood pressure on the cognitive functioning of African Americans. The purpose of this study was to examine the effect of blood pressure on memory measures in a sample of adult African Americans. Analyses were conducted on a sample of 361 African American adults (mean age 61.50 years, standard deviation 9.39 years). We found significant correlations between systolic blood pressure and most cognitive measures but only for one of the measures and diastolic blood pressure. Regressions revealed significant effects for systolic blood pressure on Digit Symbol, Telephone Interview of Cognitive Status, and Immediate Recall on the Wechsler Logical Memory test. These findings suggest that blood pressure is a source of individual variability in cognitive aging among African Americans.
OBJECTIVE/BACKGROUND: We examined the rates, predictors, and outcomes (mortality risk (MR), length of stay (LOS) and total charges (TC)) of sleep disturbances in older hospitalized ...patients.PATIENTS/METHODS: Using the U.S. Nationwide Inpatient Sample database (2002-2012), older patients (≥60y) were selected and rates of insomnia, obstructive sleep apnea (OSA) and other sleep disturbances (OSD) were estimated using ICD-9CM. TC, adjusted for inflation, was of primary interest, while MR and LOS were secondary outcomes. Multivariable regression analyses were conducted.RESULTS: Of 35,258,031 older adults, 263,865 (0.75%) had insomnia, 750,851 (2.13%) OSA and 21,814 (0.06%) OSD. Insomnia rates increased significantly (0.27% in 2002 to 1.29 in 2012, P-trend<0.001), with a similar trend observed for OSA (1.47 in 2006 to 5.01 in 2012, P-trend<0.001). TC (2012 ) for insomnia-related hospital admission increased over time from 22,250 in 2002 to 31,527 in 2012, and increased similarly for OSA and OSD; while LOS and MR both decreased. Women with any sleep disturbance had lower MR and TC than men, while Whites had consistently higher odds of insomnia, OSA, and OSD than older Blacks and Hispanics. Co-morbidities such as depression, cardiovascular risk factors, and neurological disorders steadily increased over time in patients with sleep disturbances. CONCLUSION: TC increased over time in patients with sleep disturbances while LOS and MR decreased. Further research should focus on identifying the mechanisms that explain the association between increasing sleep disturbance rates and expenditures within hospital settings and the potential hospital expenditures of unrecognized sleep disturbances in the elderly.
The current investigation examined intraindividual variability and predictors of this variability on neuropsychological measures. A total of 50 (39 women and 11 men) independently living, ...community-dwelling African Americans ranging in age from 50 to 80 years (M = 65.40, SD = 8.53) were asked to complete measures assessing socio-demographics, physical health (i.e. blood pressure and sleep), and cognitive functioning (i.e. executive function, memory, perceptual speed, constructions, and language) over 8 occasions within a 2–3 week period. The current study observed intraindividual variability across the neuropsychological measures. Results from multilevel modeling suggested that a within-person change in systolic blood pressure was positively associated with performance on executive function (e.g., Letter Fluency), particularly for those participants who on average had high systolic blood pressure and high stress. In contrast, a within-person change in sleep duration was associated with worse performance on constructions and executive functioning (e.g., Letter Fluency). Results also reflected a significant interaction between within-person change in sleep duration and average sleep duration for both perceptual speed (e.g., Number Comparison test) and executive function (e.g., Stroop task). Individuals with low sleep duration on average tended to perform poorly, particularly on those occasions when their sleep duration was below their personal average. In contrast, individuals with high sleep duration on average tended to perform poorly, particularly on those occasions when their sleep duration was above their personal average. Furthermore, daily fluctuations in sleep duration were associated with an increased risk for classification of mild cognitive impairment. The results suggest that variability on neuropsychological measures may be a useful clinical assessment of older African Americans’ cognitive competency.
The current investigation examined intraindividual variability and predictors of this variability on neuropsychological measures. A total of 50 (39 women and 11 men) independently living, ...community-dwelling African Americans ranging in age from 50 to 80 years (M = 65.40, SD = 8.53) were asked to complete measures assessing socio-demographics, physical health (i.e. blood pressure and sleep), and cognitive functioning (i.e. executive function, memory, perceptual speed, constructions, and language) over 8 occasions within a 2-3 week period. The current study observed intraindividual variability across the neuropsychological measures. Results from multilevel modeling suggested that a within-person change in systolic blood pressure was positively associated with performance on executive function (e.g., Letter Fluency), particularly for those participants who on average had high systolic blood pressure and high stress. In contrast, a within-person change in sleep duration was associated with worse performance on constructions and executive functioning (e.g., Letter Fluency). Results also reflected a significant interaction between within-person change in sleep duration and average sleep duration for both perceptual speed (e.g., Number Comparison test) and executive function (e.g., Stroop task). Individuals with low sleep duration on average tended to perform poorly, particularly on those occasions when their sleep duration was below their personal average. In contrast, individuals with high sleep duration on average tended to perform poorly, particularly on those occasions when their sleep duration was above their personal average. Furthermore, daily fluctuations in sleep duration were associated with an increased risk for classification of mild cognitive impairment. The results suggest that variability on neuropsychological measures may be a useful clinical assessment of older African Americansâ cognitive competency.
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