Biomedical subjects

James A Mortimer

Publications and source records attributed to James A Mortimer.

27 records · Page 2Linked to original sources

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↗

PubMed2002

3MS normative data for the elderly.

The Modified Mini-Mental State Examination (3MS) was developed to overcome shortcomings of the Mini-Mental Status Exam (MMSE), specifically its narrow range of possible scores and ceiling effects. Several studies have examined the psychometric characteristics of the 3MS, showing an improvement in reliability and increased sensitivity in detecting dementia in comparison to the MMSE. Despite research supporting the favorable psychometric features of the 3MS, the clinical value of the instrument is restricted by limited normative data, especially for the elderly population. In this study, we examine the influence of demographic characteristics on 3MS scores and present descriptive data for a sample of 393 community-dwelling older adults. Normative data, based on age and with adjustments for education, are provided for clinical use.

Journal Article↗

PubMedDate not supplied

Normal pressure hydrocephalus and large head size.

OBJECTIVE: To determine if patients with normal pressure hydrocephalus (NPH) have larger head size than normal controls. BACKGROUND: In 1989, Graff-Radford and Godersky noted that 3 of 30 patients diagnosed with NPH had large heads. They hypothesized that the cause of NPH in their patients was arrested congenital hydrocephalus becoming symptomatic later in life. METHODS: Participants included 31 newly diagnosed NPH patients (21 male, 10 female) seen by the same neurologist (N.R.G.-R.) at Mayo Clinic Jacksonville from January 1, 1995 through December 31, 2000, and 459 normal controls (226 male, 233 female) from the Charlotte County Healthy Aging Study. RESULTS: Head size was statistically larger for NPH males (median, 59.0 cm, range, 57.0-63.0 cm) compared with normal males (median, 57.8 cm, range, 53.3-62.8) (p < 0.01). Head size was also larger for NPH females (median, 6.3 cm, range, 53.5-58.0 cm) compared with normal females (median, 54.6 cm, range, 51.4-59.7 cm) (p < 0.02). CONCLUSION: Patients with NPH have larger head circumferences as a group than normal controls. This was found in both males and females. Results suggest that a significant proportion of patients with NPH may have congenital hydrocephalus that becomes symptomatic later in life.

Aged↗

PubMedDate not supplied

Tools of the epidemiologist.

This review provides a summary of epidemiologic tools to facilitate understanding of the design and analysis of studies of Alzheimer disease (AD) and related disorders. Proportions, ratios, rates, prevalence, incidence, study designs, bias, confounding, effect modification, odds and risk ratios, statistical power, and confidence intervals are defined and discussed. Descriptive epidemiology is concerned with describing the distribution of disease by person, place, and time. It is useful for hypothesis generation, but not generally for hypothesis testing. Observational analytic epidemiology focuses on identifying putative causes for an illness. Although its primary mission is hypothesis testing, it can lead to new hypotheses as well. Finally, experimental analytic epidemiology or clinical trials can provide rigorous tests of presumed causal associations. The strengths and limitations of various designs as they apply to determining causal associations in studies of AD and dementia are reviewed. Over the past 60 years, the epidemiologic study of dementia has evolved from basic descriptive studies of prevalence and incidence to case-control and cohort studies and finally to the first clinical trials to prevent AD.

Alzheimer Disease↗

PubMedDate not supplied

Early-life risk factors for Alzheimer disease.

Research findings obtained over the past 20 years suggest that Alzheimer disease (AD) may have its origins in early life. In this review, we consider the evidence for early-life risk factors for this illness. We propose that risk factors that predict neuropathology are largely distinct from those related to the clinical expression of Alzheimer disease. Early-life risk factors for pathology include genes, chromosomal abnormalities, head injury, insulin resistance, and inflammation. With regard to risk factors for clinical expression of Alzheimer disease, six general groups of childhood exposures are reviewed: (1) perinatal conditions, (2) early-life brain development, (3) early-life body growth, (4) early-life socioeconomic conditions, (5) environmental enrichment, and (6) cognitive reserve. The literature reviewed suggests that risk of Alzheimer disease is probably not determined in any single time period but results from the complex interplay between genetic and environmental exposures throughout the life course. Enhancement or preservation of brain or cognitive reserve could delay the onset of Alzheimer disease and in some cases prevent the disease from occurring altogether.

Alzheimer Disease↗