Cognitive performance predicts treatment decisional abilities in mild to moderate dementia

Abstract

Objective-To examine the contribution of neuropsychological test performance to treatment decision-making capacity in community volunteers with mild to moderate dementia.Methods-The authors recruited volunteers (44 men, 44 women) with mild to moderate dementia from the community. Subjects completed a battery of 11 neuropsychological tests that assessed auditory and visual attention, logical memory, language, and executive function. To measure decision making capacity, the authors administered the Capacity to Consent to Treatment Interview, the Hopemont Capacity Assessment Interview, and the MacCarthur Competence Assessment Tool-Treatment. Each of these instruments individually scores four decisional abilities serving capacity: understanding, appreciation, reasoning, and expression of choice. The authors used principal components analysis to generate component scores for each ability across instruments, and to extract principal components for neuropsychological performance.Results-Multiple linear regression analyses demonstrated that neuropsychological performance significantly predicted all four abilities. Specifically, it predicted 77.8% of the common variance for understanding, 39.4% for reasoning, 24.6% for appreciation, and 10.2% for expression of choice. Except for reasoning and appreciation, neuropsychological predictor (β) profiles were unique for each ability.Conclusions-Neuropsychological performance substantially and differentially predicted capacity for treatment decisions in individuals with mild to moderate dementia. Relationships between elemental cognitive function and decisional capacity may differ in individuals whose decisional capacity is impaired by other disorders, such as mental illness.Capacity for treatment decisions hinges on four legal standards, or abilities [1][2][3][4] : understanding (comprehension of diagnostic and treatment information), appreciation (personalization of information through integration with one's values, beliefs, and expectations), reasoning (evaluation of treatment alternatives in light of potential consequences for everyday life), and expression of choice (communication of a treatment Address correspondence and reprint requests to: Dr. Ronald J. Gurrera, VA Boston Healthcare System, 940 Belmont Street (116A), Brockton, MA 02301; Ronald.Gurrera@med.va.gov or Ronald_Gurrera@hms.harvard.edu. Disclosure: The authors report no conflicts of interest. It is logical to examine the neuropsychological correlates of decisional abilities for ways in which to refine their assessment, 8,19,24 and preliminary studies are encouraging with respect to the feasibility of this approach. 8,25,26 The authors evaluated the contribution of neuropsychological task performance to decisional abilities in community volunteers with mild to moderate dementia. They hypothesized that each ability would be significantly predicted by a distinct subset of neuropsychological tasks, and that understanding would be most, and expression of choice least, strongly associated with neuropsychologi...

Cognitive models of medical decision-making capacity in patients with mild cognitive impairment

“…This relative weakness in the cognitive models of appreciation is consistent with findings from prior studies (Dymek et al, 2001;Gurrera et al, 2006), and underscores that appreciation is the consent standard that probably relies most heavily on abilities not fully represented in the neuropsychological armamentarium (Marson et al, 1996). Consequently, performance on appreciation is less well modeled by standard cognitive measures.…”

“…With regard to MDC, such studies can alert clinicians to specific cognitive impairments threatening consent capacity in MCI. In turn, these findings can facilitate the development of enhanced consent procedures for persons with MCI (Gurrera et al, 2006;Marson et al, 1996;Mittal et al, 2007).…”

MacArthur Competence Assessment Tool for Treatment in Alzheimer disease: cross-cultural adaptation

“…Moreover, our results also showed that expressing a choice was not related to the other abilities; it was only related to the awareness of the disease. In practice, most mild to moderate patients with AD will be able to express a treatment choice, even if their ability to understand, appreciate or reason is inadequate to support the choice 29 , but patients with AD who had awareness of their overall cognitive function and diagnosis were more likely to be judged competent by physicians 5 . Moreover, the factors related to understanding were reasoning and functional status.…”

“…Among the four abilities, understanding is the most stringent consent standard, as it requires comprehension of factual knowledge and understanding of the treatment situation and choices 1,4,6,29 . In previous studies, it has been observed that competence to consent to treatment was especially impaired in patients with AD 5 when cognitive functioning had significantly low scores 29 . The functional status is probably related to understanding because people with lower functional status may be less stimulated and this may hinder comprehension.…”

Can the Mini-Mental State Examination Predict Capacity to Consent to Treatment?

“…This would surely burden people with dementia and affect the results of an assessment with the MacCAT-T. Thirdly, the verbal retrieval factor was based on the factorial analysis of Gurrera et al (2006), but was modified for this study. While the original verbal retrieval factor used the immediate and delayed logical memory subtests (Wechsler, 1997) in addition to the Boston Naming Test, we used the Word List Memory (immediate memory) and Word List Recall (delayed memory) subtests of the CERAD-NP.…”