Neuropsychological performance within-person variability is associated with reduced treatment consent capacity

[MacCAT-T between Claim and Practice - Challenges of Assessing Capacity for Consent in Dementia]

BACKGROUND

Consent is a prerequisite for medical diagnostic and therapeutic action. There is no standardised procedure for assessing the ability to give consent. The most widely used tool for structured assessment is the MacArthur Competence Assessment Tool for Treatment (MacCAT-T).

OBJECTIVES

 People with dementia have impaired capacity to consent because of their disease. In order to answer the question to what extent structured assessment procedures can be usefully applied to people with dementia, we analyse the function, strengths and weaknesses of structured assessment procedures with a focus on the MacCAT-T and discuss suggestions for modification and further development of the tool.

METHODS

Using the PubMed literature database, a systematic literature search and analysis was conducted on papers published since 2010, following PRISMA guidelines.Results Although the MacCAT-T is a valid and reliable tool, it cannot comprehensively address memory problems in people with dementia. It primarily measures cognitive functions. However, Decisions based on emotions, intuitions and values, are not captured by the MacCAT-T. Communicative limitations in people with dementia are not taken into account.

CONCLUSIONS

 It is recommended to provide information in simple language, written down and visualised for people with dementia. The development and elaboration of a graduated procedure for the examination of capacity to consent is indicated. The gradations of the scope and depth of the assessment to be determined should be based on the severity of the cognitive impairment, the benefit/risk ratio of the proposed medical intervention and the individual profile of affective functions and value-based imprints.

Determining medical decision-making capacity in brain tumor patients: why and how?

Background

Brain tumor patients are at high risk of impaired medical decision-making capacity (MDC), which can be ethically challenging because it limits their ability to give informed consent to medical treatments or participation in research. The European Association of Neuro-Oncology Palliative Care Multidisciplinary Task Force performed a systematic review to identify relevant evidence with respect to MDC that could be used to give recommendations on how to cope with reduced MDC in brain tumor patients.

Methods

A literature search in several electronic databases was conducted up to September 2019, including studies with brain tumor and other neurological patients. Information related to the following topics was extracted: tools to measure MDC, consent to treatment or research, predictive patient- and treatment-related factors, surrogate decision making, and interventions to improve MDC.

Results

A total of 138 articles were deemed eligible. Several structured capacity-assessment instruments are available to aid clinical decision making. These instruments revealed a high incidence of impaired MDC both in brain tumors and other neurological diseases for treatment- and research-related decisions. Incapacity appeared to be mostly determined by the level of cognitive impairment. Surrogate decision making should be considered in case a patient lacks capacity, ensuring that the patient's "best interests" and wishes are guaranteed. Several methods are available that may help to enhance patients' consent capacity.

Conclusions

Clinical recommendations on how to detect and manage reduced MDC in brain tumor patients were formulated, reflecting among others the timing of MDC assessments, methods to enhance patients' consent capacity, and alternative procedures, including surrogate consent.

Imaging the aging brain: study design and baseline findings of the SENIOR cohort

Background

Current demographic trends point towards an aging society entailing increasing occurrence and burden of neurodegenerative diseases. In this context, understanding physiological aging and its turning point into neurodegeneration is essential for the development of possible biomarkers and future therapeutics of brain disease.

Methods

The SENIOR study represents a longitudinal, observational study including cognitively healthy elderlies aged between 50 and 70 years old at the time of inclusion, being followed annually over 10 years. Our multimodal protocol includes structural, diffusion, functional, and sodium magnetic resonance imaging (MRI) at 3 T and 7 T, positron emission tomography (PET), blood samples, genetics, audiometry, and neuropsychological and neurological examinations as well as assessment of neuronal risk factors.

Results

One hundred forty-two participants (50% females) were enrolled in the SENIOR cohort with a mean age of 60 (SD 6.3) years at baseline. Baseline results with multiple regression analyses reveal that cerebral white matter lesions can be predicted by cardiovascular and cognitive risk factors and age. Cardiovascular risk factors were strongly associated with juxtacortical and periventricular lesions. Intra-subject across-test variability as a measure of neuropsychological test performance and possible cognitive marker predicts white matter volume and is significantly associated with risk profile. Division of the cohort into subjects with a higher and lower risk profile shows significant differences in intra-subject across-test variability and volumes as well as cortical thickness of brain regions of the temporal lobe. There is no difference between the lower- and higher-risk groups in amyloid load using PET data from a subset of 81 subjects.

Conclusions

We here describe the study protocol and baseline findings of the SENIOR observational study which aim is the establishment of integrated, multiparametric maps of normal aging and the identification of early biomarkers for neurodegeneration. We show that intra-subject across-test variability as a marker of neuropsychological test performance as well as age, gender, and combined risk factors influence neuronal decline as represented by decrease in brain volume, cortical thickness, and increase in white matter lesions. Baseline findings will be used as underlying basis for the further implications of aging and neuronal degeneration as well as examination of brain aging under different aspects of brain pathology versus physiological aging.

Hubness of strategic planning and sociality influences depressive mood and anxiety in College Population

Depressive mood and anxiety can reduce cognitive performance. Conversely, the presence of a biased cognitive tendency may serve as a trigger for depressive mood-anxiety. Previous studies have largely focused on group-wise correlations between clinical-neurocognitive variables. Using network analyses for intra-individual covariance, we sought to decipher the most influential clinical-neurocognitive hub in the differential severity of depressive-anxiety symptoms in a college population. Ninety college students were evaluated for depressive-anxiety symptoms, Minnesota multiphasic personality inventory-2(MMPI-2), and neuro-cognition. Weighted and undirected version of the intra-individual covariance networks, comprised of 18 clinical-neurocognitive variables satisfied small-worldness and modular organization in the sparsity range of K = 0.20-0.21. Furthermore, betweenness centrality of perseverative error for the Wisconsin card sorting test was reduced in more depressive individuals; higher anxiety was related to the increased betweenness centrality of MMPI-2 clinical scale 0(Si). Elevated edge-betweenness centrality of covariance between the MMPI-2 clinical scale 7(Pt) versus commission error of the continuous performance test predicted more anxiety higher than depressive mood. With intra-individual covariance network of clinical-neurocognitive variables, this study demonstrated critical drivers of depressive mood[attenuated influence of strategic planning] or anxiety[domination of social introversion/extroversion, in addition to the influence of compulsivity-impulsivity covariance as a shortcut component among various clinical-neurocognitive features].

Decisions and attitudes regarding participation and proxy in clinical trials among patients with impaired cognitive function

Background

Medical decision-making capacity is impaired in Alzheimer’s disease and mild cognitive impairment. Medical decision-making capacity depends on many different cognitive functions and varies due to situation and cognitive, social, and emotional status of the patient. Our aim was to analyze dementia patients’ capacity to estimate risks and benefits in different clinical trials and determine how cognitive decline affects their attitude toward possible participation and proxy consent.

Methods

Groups: Alzheimer’s disease (n = 20), mild cognitive impairment (n = 21) and healthy controls (n = 33). Two hypothetical clinical trials, a standardized interview and three visual analogue scales were used to investigate decisions, estimations, reasoning, and attitudes.

Results

A general positive attitude toward participation in clinical trials was shown among all groups. Both patients and controls motivated possible participation as “own-benefit” in the low-risk trial and to “help-others” in the high-risk trial. Individuals who accepted to participate in the high-risk trial scored lower in medical decision-making capacity in comparison to participants who would not have participated (p < .01). Patients in the Alzheimer’s disease but not mild cognitive impairment and healthy control groups underestimated risks and overestimated benefits in the high-risk/low-benefit trial (p < .05). A family member was most frequently chosen as possible proxy (91%).

Conclusions

Medical decisions and research consent should be interpreted with caution in patients who are already in early stages of dementia, as the patients’ acceptance to participate in high-risk trials may be due an insufficient decisional capacity and risk analysis, accelerated by a general desire to make good to society. We emphasize the use of a standardized tool to evaluate medical decisional capacity in clinical research.

Assessment of Healthcare Decision-making Capacity

It is often necessary for neuropsychologists, clinical psychologists, and other healthcare professionals to assess an individual's capacity to consent to treatment related to healthcare. This task can be challenging and requires a delicate balance of both respect for individuals' autonomy, as well as the protection of individuals with diminished capacity to make an autonomous decision. The purpose of the present review is to provide an overview of the conceptual model of decisional capacity as well as a brief summary of some of the currently available instruments designed to help evaluate medical decision making. In addition, current empirical literature on the relationship between neuropsychological abilities and decision-making capacity is discussed and a brief set of recommendations is provided to further aid clinicians or consultants when they are required to complete the ethically important but difficult task of making determinations about healthcare decision-making capacity.