Biomedical subjects

James A Mortimer

Publications and source records attributed to James A Mortimer.

At least 19 recordsLinked to original sources

PubMed2005

Complete ascertainment of dementia in the Swedish Twin Registry: the HARMONY study.

The purpose of this report is to describe the Study of Dementia in Swedish Twins (known as HARMONY), including procedures for complete ascertainment of all cases of Alzheimer's disease (AD) and other dementias in 14,435 individuals aged 65 and older from the national Swedish twin registry. Telephone cognitive screening identified 11.5% as positive for cognitive dysfunction. Clinical diagnoses were completed for 1557 individuals, including individuals who screened positive, their twin partners, and a sample of normal controls. Estimated prevalence of dementia ranged from 1.4% for age 65-69 to 29.2% for age 90 and older. Concordance rates for Alzheimer's disease were 59% for monozygotic twins, 32% for like-sexed, and 24% for unlike-sexed dizygotic twins. Among monozygotic twins where both twins had Alzheimer's disease, the within pair difference in age of onset ranged from both becoming demented in the same year to 7 years difference in onset.

Age Factors↗

PubMed2005

Developmental and vascular risk factors for Alzheimer's disease.

To investigate developmental and vascular risk factors for Alzheimer's disease (AD), we examined 90 incident cases of probable AD in a cohort of 1859 individuals followed prospectively for six years. The presence of the APOE-epsilon4 allele was the strongest risk factor, and with increasing survival age, the effect of epsilon4 diminished. Among epsilon4 positives, developmental risk factors such as smaller head circumference (< or =54.4 cm) and having more than four children in the household at age 2-3 were independently associated with incident AD (hazard ratio (HR)=2.6 (95% CI 1.04-6.3) and 3.3 (1.2-9.2), respectively). Among epsilon4 negatives, vascular risk factors were related to AD risk (self-reported diagnoses of transient ischemic attack and diabetes (HR=5.1, 95% CI 1.7-15.5; HR 3.3, 95% CI 1.4-8.1)). These findings indicate that clinical AD is a result of early life as well as later life risk factors, and that genetic predisposition to the disease may modify the constellation of predictors.

Age Factors↗

PubMed2005

Florida Cognitive Activities Scale: initial development and validation.

We used a rational-empirical approach in the construction and validation of a cognitive activity scale for use with elderly populations. The scale development effort produced a 25-item scale with a reasonably high level of internal consistency in a sample of 200 elderly individuals. Scale scores were positively correlated with years of education and measures of various domains of cognitive ability. In a separate cross-validation sample, a similar pattern of reliability and validity coefficients was obtained. The full scale score was found to contribute significantly to the prediction of cognitive ability after controlling for the effects of age, education, and gender. Two subscales (Higher Cognitive Abilities and Frequent Cognitive Abilities) and a measure of self-reported maintenance of cognitive activity were also developed. In a separate study, the maintenance score was found to differ significantly between the validation sample and a sample of individuals with a history of neurological disorder, with a moderate effect size (d approximately = .7). Further cross-validation studies in minority groups and groups of varying socioeconomic status will be critical in establishing the research and clinical value of the scale and subscales.

Aged↗

PubMed2004

Normative data for elderly African Americans for the Stroop Color and Word Test.

The Stroop Color and Word Test is a measure of executive function that is commonly used in neuropsychological evaluations, but for which there are currently no normative date for elderly African American individuals. The present investigation examined the influence of demographic characteristics on this measure in a community-dwelling sample of 236 elderly African American adults (60-84 years of age). Age, education, gender, and the education by gender interaction were found to affect performance on the Stroop Color and Word Test tasks. Based on these results, normative tables for Stroop Color and Word Test scores, stratified by age and with score adjustments for education and gender, are provided.

Black or African American↗

PubMed2003

Neuronal loss is greater in the locus coeruleus than nucleus basalis and substantia nigra in Alzheimer and Parkinson diseases.

CONTEXT: Alzheimer disease (AD) and Parkinson disease (PD) are associated with neuronal degeneration in major subcortical nuclei, but few studies have examined the neuronal degeneration in these nuclei concurrently. OBJECTIVE: To identify clinical and pathological correlates of neuronal loss in the nucleus basalis (NB), locus coeruleus (LC), and substantia nigra pars compacta (SN) in AD and PD. DESIGN: The study sample comprised 86 cases with pathologically confirmed AD, 19 cases with PD, and 13 healthy elderly control subjects. The number of nucleolated neurons was counted in representative sections of the NB, LC, and SN. Effect sizes (ES) were computed to determine the standardized difference in cell counts relative to healthy controls. RESULTS: Cases of AD showed the greatest neuronal loss in the LC (ES = 3.16) followed by the NB (ES = 1.10), but variable loss in the SN (ES = 0.16). Cases of PD also showed the greatest neuronal loss in the LC (ES = 6.47), followed by the SN (ES = 2.58) and the NB (ES = 0.85). Significant correlations were found between the number of neurons in the NB and LC in PD (r = 0.54, P<.05), as well as AD (r = 0.24, P<.05). The duration of illness correlated with greater neuronal loss in the LC and NB in AD, and greater neuronal loss in the SN in PD. CONCLUSIONS: For both AD and PD the greatest neuronal loss was found in the LC. In AD, neuronal loss was most severe and best correlated with the duration of illness in the LC, rather than in NB as traditionally expected. Correlations between neuronal loss in the LC and NB (but not SN) in both PD and AD suggest that the former 2 nuclei may share common pathogenetic susceptibilities. Given the prominent loss of neurons in the LC, detection and treatment of noradrenergic deficiencies warrant attention in both AD and PD.

Age of Onset↗

PubMed2003

Effects of the use of alcohol and cigarettes on cognition in elderly African American adults.

In this study we examined the independent and interactive effects of lifetime patterns of drinking and smoking on cognitive performance in elderly African Americans. A sample of 230 individuals with varying histories of alcohol and cigarette use was drawn from the Hillsborough Elder African American Life Study, a community-based, cross-sectional study of older adults aged 60 to 84. Dependent variables were the results of a neuropsychological battery that provided measures of general cognitive ability, executive function, and memory. Specifically, our study addressed (1) whether individuals with a lifetime history of sustained smoking and/or drinking show lower levels of cognitive performance in comparison to lifetime abstainers, (2) whether cumulative lifetime doses of alcohol or cigarettes, or of the two substances in interaction, have an effect on cognition, and (3) whether individuals who have histories of periodic, intense use of either alcohol or cigarettes show lower levels of cognitive performance in comparison to lifetime abstainers. When significant results were obtained, effect sizes were small, not exceeding 5% of the variance. A single exception occurred for the intensity analyses, in which drinking explained approximately 16% of the variance in global cognitive ability after adjusting for the contributions of control variables. In these analyses, drinking was found to have a U-shaped effect on global cognitive ability and total acquisition in the memory trials. Specifically, moderate users performed at a lower level than abstainers or heavy users, who did not differ from each other.

Black or African American↗

PubMed2003

3MS normative data for elderly African Americans.

The Modified Mini-Mental State Examination (3MS) is an expanded and modified version of the Mini-Mental Status Exam (MMSE). Although the MMSE has achieved widespread clinical use as a brief cognitive screen, the utility of the measure to ascertain cognitive impairment is constrained by a limited set of abilities sampled, a narrow range of possible scores, floor and ceiling effects, and by a paucity of normative data for use with older adults from ethnically diverse backgrounds. Research demonstrates that the reliability, validity, and sensitivity of the 3MS are superior to that of the MMSE in detecting cognitive impairment. To date there has been minimal research investigating the usefulness of the 3MS with African American older adults. The current study examined the influence of demographic characteristics on the 3MS in a community-dwelling sample of 238 African American older adults (60-84 years). Age, gender, and education accounted for moderate amounts of variance in 3MS performance. Based on these results, normative tables for 3MS scores, stratified by age and with score adjustments for education and gender, are provided.

Black or African American↗

PubMed2003

Head circumference, education and risk of dementia: findings from the Nun Study.

To examine the prevalence of dementia associated with having a smaller brain, lower education or both of these characteristics, 294 Catholic sisters were assessed annually for dementia. Sixty participants died and their brains were evaluated to determine fulfillment of neuropathological criteria for Alzheimer's disease (AD). Lower educational attainment and the interaction of smaller head circumference with lower education were associated with the presence of dementia, controlling for age and the presence of one or more apolipoprotein E-epsilon 4 alleles. By contrast, neither low educational attainment nor head circumference was significantly associated with fulfillment of neuropathological criteria for AD. Individuals having both low education and small head circumference were four times as likely to be demented as the rest of the sample. The findings suggest that higher education and larger head size, alone or in combination, may reduce the risk of expressing dementia in late life.

Aged↗

PubMed2003

Determinants of a sense of mastery in African American and White older adults.

OBJECTIVES: This study compares determinants of a sense of mastery in African American and White older adults. METHODS: The association between predictor variables (sociodemographic variables, health conditions, social resources, and religiosity) and feelings of mastery was assessed by using representative community-dwelling samples of 250 African American (mean age = 71.6) and 452 White (mean age = 73.0) older adults. RESULTS: African American older adults had a lower sense of mastery than White older adults. Significant modification by race was found in the associations of age, self-rated health, and religiosity with feelings of mastery. The negative effects of old age and poor health on feelings of mastery were stronger in the White sample, whereas the positive effect of religiosity on feelings of mastery was observed only in the African American sample. DISCUSSION: Although African American older adults had a lower sense of mastery than Whites, their feelings of mastery were less likely to be diminished by old age and poor health and more likely to be enhanced by religiosity. Possible explanations for cross-racial differences are discussed, as are implications.

Black or African American↗

PubMed2002

Telephone screening to identify potential dementia cases in a population-based sample of older adults.

This study examined the utility of the TELE, a telephone assessment for dementia, in a sample of 269 individuals that was not selected on the basis of previous dementia diagnosis. Thus, the conditions of the study reflect the actual situation in which a screening instrument might be employed. Scores on TELE were compared to dementia diagnoses. Using the best cutoff score, sensitivity was .86 and specificity was .90. Longitudinal follow-up established that false positives primarily included those who subsequently developed dementia. Telephone screening for dementia has both clinical and research applications. One recommendation based on our experience is that longitudinal studies should include a telephone interview component for anyone who drops out of the study, to enable characterizing the cognitive status of dropouts.

Aged↗

PubMed2002

Effects of the use of alcohol and cigarettes on cognition in elderly adults.

The objective of this study was to examine the independent and interactive effects of lifetime patterns of drinking and smoking on cognitive performance in the elderly. A sample of 395 individuals with varying histories of alcohol and cigarette use was drawn from the Charlotte County Healthy Aging Study, a community-based, cross-sectional study of randomly selected older adults of age 60 to 84. Dependent variables were the results of a neuropsychological battery that provided measures of general cognitive ability, executive function, and memory. Specifically, we examined (1) differences in performance among groups of abstainers, drinkers, and smokers, (2) the effects of lifetime drinking and smoking dose on cognition within the group of users, and (3) the effects of intensity of drinking and smoking on cognition. Potential methodological confounds, such as age, education, and medical history, were controlled by means of sampling and covariance procedures. Analyses failed to provide evidence for a beneficial J-curve or threshold effect for drinking, but did not reveal any detrimental effect. No detrimental effect of smoking was found in any analysis; nor was there any evidence of an interaction between alcohol and cigarette use on any cognitive measure.

Aged↗

PubMed2002

Similarities and differences in attitudes toward long-term care between Japanese Americans and Caucasian Americans.

The purpose of this study was to compare attitudes toward the use of long-term care between older Japanese Americans (n = 1,244) and older Caucasian Americans (n = 1,354). When presented with a hypothetical situation in which they have dementia, 39% of older Japanese Americans and 42% of older Caucasians intended to be cared for at home, whereas 53% versus 38%, respectively, intended to use nursing home care (P <.001). If the hypothetical situation was hip fracture, 81% of older Japanese Americans and 72% of older Caucasians intended to be cared for at home, with 13% of both groups intending to use nursing home care (P = NS). The subjects' perceptions of what their families, friends, ministers, and communities would want them to choose differed, with more uncertainty among Caucasians (P <.001). For provision of home care, Japanese Americans were more likely to rely on loved ones than Caucasians, who were more likely to rely on paid providers. Multivariate logistic regression showed ethnicity to be independently related to intention to use nursing home care in the dementia scenario, controlling for demographic variables. Being married lowered the odds of intending to use nursing homes in any situation. We conclude that Caucasian Americans intend to use paid home health care at higher rates than Japanese Americans if they become disabled by dementia. Japanese Americans demonstrated more certainty about the influences of others on their opinions, suggesting a more stable cultural norm in this population, and intended to use more nursing home care in the event of permanent debility (dementia).

Aged↗

PubMed2002

Hopkins Verbal Learning Test-Revised: norms for elderly African Americans.

The Hopkins Verbal Learning Test-Revised (HVLT-R) is a memory test commonly used in neuropsychological evaluations, but for which there are currently no normative data for elderly African Americans. The current study examined the influence of demographic characteristics on HVLT-R performance measures in a community-dwelling sample of 237 African American older adults (60-84 years). Age, gender, and education accounted for moderate amounts of variance in HVLT-R performance. Based on these results, normative tables for HVLT-R scores, stratified by age and with score adjustments for education and gender, are provided.

Black or African American↗

PubMed2002

Nonauditory determinants of self-perceived hearing problems among older adults: the role of stressful life conditions, neuroticism, and social resources.

BACKGROUND: The present study explored factors that influenced older individuals' subjective perception of hearing problems. In addition to objectively screened hearing ability, nonauditory factors such as stressful life conditions (visual impairment, chronic disease, disability, and recent stressful life events), neuroticism, and social resources were hypothesized to be predictors of self-perceived hearing problems. METHODS: These hypotheses were tested with a hierarchical regression model using a stratified sample of 425 community-dwelling older individuals (mean age = 72.2). RESULTS: Individuals with more recent stressful life events, higher levels of neuroticism, and less emotional support reported greater hearing problems after controlling for objectively screened hearing. In addition to the main effects, a significant interaction was observed between neuroticism and screened hearing, indicating that the combination of poor hearing and high neuroticism increased the level of self-perceived hearing problems. CONCLUSIONS: The findings suggest that the effects of nonauditory factors should be taken into account in the application of self-assessed measures of hearing problems.

Aged↗

PubMed2002

The role of mastery and social resources in the associations between disability and depression in later life.

PURPOSE: Although disability is widely acknowledged as a risk factor for late-life depression, few studies have studied the potential of psychosocial factors to alter the association between disability and depression. The present study assessed the impacts of mastery and social resources (social network, social support, and satisfaction with support) on depression and, in particular, whether they modify the link between disability and depression. DESIGN AND METHODS: The direct and moderating effects of mastery and social resources were empirically tested using a sample of 406 community-dwelling older adults who were cognitively intact (mean age = 72.3). RESULTS: Higher level of mastery and greater satisfaction with support had significant direct effects on depression and also buffered the adverse impact of disability on depression. IMPLICATIONS: The findings support the importance of psychosocial factors in modifying the association between disability and depression and suggest that efforts to enhance positive psychosocial attributes should be emphasized in interventions for older adults.

Activities of Daily Living↗

PubMed2002

The role of neuroticism in the association between performance-based and self-reported measures of mobility.

OBJECTIVE: The present study examined the role of neuroticism in older individuals' self-reports of mobility. The authors hypothesized that neuroticism would modify the association between performance-based and self-reported measures of mobility. METHOD: Using a stratified sample of 459 community-dwelling elders, a hierarchical regression analysis was conducted to assess the effects of physical performance and neuroticism in predicting self-reported mobility. RESULTS: Composite measures of lower body performance and self-reported mobility had a moderate correlation. In the regression model of self-reported mobility, neuroticism had both a direct effect and an interaction effect with physical performance. DISCUSSION: Given a certain level of physical performance, individuals who scored high on neuroticism were more likely to report disability. Also, the combination of poor performance and high neuroticism increased self-reported disability. The findings suggest that neuroticism may play an important role in subjective perception and should be considered in the interpretation of data based on self-reports.

Age Factors↗

PubMed2002

Non-familial Alzheimer's disease is mainly due to genetic factors.

This team takes the position that what is commonly referred to as non-familial Alzheimer's disease (AD) is predominantly due to genetic factors. Population-based studies suggest that genetic factors cause the majority of cases that begin after age 60. There are several lines of evidence supporting this position: Data from the Nun Study suggest that the risk for AD is largely established by early adulthood, implying that later adult exposures likely play only a small role in causation. Family studies show that first-degree blood relatives of persons with non-familial AD have a substantially increased risk of AD relative to controls. Twin studies suggest that the heritability of AD exceeds 60%. Environmental factors, such as socioeconomic status, education, and head injury, are strong risk factors for AD only in individuals with a genetic predisposition. The APOE genotype is a powerful risk factor for AD and accounts for as much as 50%. There are numerous other candidate genes with strong associations with AD that presumably explain the remaining population risk. This paper further reviews the mechanisms associated with AD causation for APOE and other candidate genes and implications for the development of prevention strategies.

Adult↗

PubMed2002

Elderly norms for the Spot-the-Word test.

This study provides population-based normative data for healthy, community-dwelling American elderly on the Spot-the-Word test (STW). The effects of age, education, and gender on STW performance are also investigated. Given previously limited normative data for the elderly, the current norms expand the clinical utility of STW as an estimate of premorbid intelligence. Significant but small effects were found for age on STW performance. Significant and moderate effects were found for education. Therefore, normative adjustments are provided for education. Consistent with previous research, no effect was found for gender.

Journal Article↗