Tests, Tests, and More Tests: A New Era for Dementia Diagnosis

Cerebrospinal fluid: CSF) proteins correlate with pathological changes that are hallmarks of Alzheimer’s disease: AD). CSF biomarkers have been used in research settings to predict AD diagnosis and rate of cognitive decline, however their use in clinical settings is limited. Given their potential utility in identifying preclinical AD and in increasing diagnostic confidence in clinical settings, we sought to understand how clinicians use CSF biomarkers in conjunction with other clinical details to diagnose AD. Participants: N = 193) were physicians and other medical professionals who routinely evaluate older adults for neurodegenerative disease. In a within-subjects factorial design, participants were randomized and viewed normal, borderline, AD-consistent, or no CSF information along with two clinical vignettes portraying patients with borderline and mild AD symptoms. In addition, clinicians reported on their use and the utility of CSF lab results in clinical practice. Clinicians reported infrequent use and limited utility of CSF biomarkers in clinical practice, yet CSF biomarkers affected clinical decisions on two vignettes. AD-consistent CSF values made clinicians 6-12 times more likely to make an AD-related diagnosis, increased diagnostic confidence, and led clinicians to initiate treatment more often than other CSF values. Furthermore, clinicians relied on CSF evidence more heavily when AD-consistent CSF values were presented in the context of a borderline case of memory impairment. In sum, CSF biomarkers have a significant impact on clinical decisions, and show different effects depending on contextual factors. Therefore, as CSF biomarkers become more widespread in clinical practice, clinicians should consider the potentially significant effect of biomarkers on their clinical decisions

The ideological divide in confidence in science and participation in medical research

Abstract In the United States, the wide ideological divergence in public confidence in science poses a potentially significant problem for the scientific enterprise. We examine the behavioral consequences of this ideological divide for Americans’ contributions to medical research. Based on a mass survey of American adults, we find that engagement in a wide range of medical research activities is a function of a latent propensity to participate. The propensity is systematically higher among liberals than among conservatives. A substantial part of this ideological divide is due to conservative Americans’ lower confidence in science. These findings raise important issues for the recruitment of subjects for medical studies and the generalizability of results from such studies

Risk Communication for Preclinical Alzheimer\u27s Disease

Recent biomedical research has focused on early detection of Alzheimer’s disease (AD) pathology in people who do not yet have symptoms of the disease. This focus represents a shift in current diagnostic practices from detection of cognitive impairment to include detection of disease risk. This study examines attitudes regarding preclinical risk detection for AD in individuals aged 19-65 recruited online using Amazon’s Mechanical Turk. Participants were randomized to view an educational intervention (varying method and depth of education) and viewed a videotaped disclosure of hypothetical risk for AD to themselves (varying level of risk). Participants reported on several individual difference variables (e.g., prior knowledge, experience with AD) as well as their interest in predictive testing and subjective risk of AD. The results of this study show that prior knowledge, experience with AD, depth of education, and level of risk disclosed interact to influence subjective risk estimates. These findings have implications for the development of empirically-supported education interventions and disclosure processes for preclinical AD

Executive functions in premanifest Huntingtons disease.

BACKGROUND: We investigated the viability of psychometrically robust executive function measures as markers for premanifest Huntingtons disease (HD). METHODS: Fifteen premanifest HD subjects and 42 controls were compared on the NIH EXAMINER executive function battery. This battery yields an overall executive composite score, plus working memory, cognitive control, and fluency scores that are measured on psychometrically matched scales. The scores were correlated with two disease markers, disease burden and striatal volumes, in the premanifest HD subjects. RESULTS: The premanifest HD subjects scored significantly lower on the working memory score. The executive composite positively correlated with striatal volumes, and the working memory score negatively correlated with disease burden. The cognitive control and fluency scores did not differ between the groups or correlate significantly with the disease markers. CONCLUSIONS: The NIH EXAMINER executive composite and working memory scores are sensitive markers of cognitive dysfunction, striatal volume, and disease burden in premanifest HD

Executive functions in premanifest Huntington's disease.

BackgroundWe investigated the viability of psychometrically robust executive function measures as markers for premanifest Huntington's disease (HD).MethodsFifteen premanifest HD subjects and 42 controls were compared on the NIH EXAMINER executive function battery. This battery yields an overall executive composite score, plus working memory, cognitive control, and fluency scores that are measured on psychometrically matched scales. The scores were correlated with two disease markers, disease burden and striatal volumes, in the premanifest HD subjects.ResultsThe premanifest HD subjects scored significantly lower on the working memory score. The executive composite positively correlated with striatal volumes, and the working memory score negatively correlated with disease burden. The cognitive control and fluency scores did not differ between the groups or correlate significantly with the disease markers.ConclusionsThe NIH EXAMINER executive composite and working memory scores are sensitive markers of cognitive dysfunction, striatal volume, and disease burden in premanifest HD