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

Abstract

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.

Cognitive, Emotional, and Daily Functioning Domains Involved in Decision-Making among Patients with Mild Cognitive Impairment: A Systematic Review

“…Deficits in memory and reasoning may affect medical DM differently as patients are required to recall the risks and benefits of each treatment option as well as to balance/compare them to justify the decision made [ 94 ]. While the aforementioned studies relied on the utilization of the Capacity to Consent Treatment Instrument (CCTI; [ 106 ]), other works adopted the Linguistic Instrument for Medical Decision-Making (LIMD) to measure the requirements for medical choices, finding altered responses in groups with different profiles of cognitive impairment [ 73 , 84 , 86 ]. Mental abilities covering clinical judgement appeared to be preserved in MCI despite lower DM scores for other areas of daily life, compared to those of cognitively spared individuals [ 88 ].…”

“…One recent study investigated the decisions and attitudes concerning participation in clinical trials under different conditions of risks, highlighting differences only in the group with AD and non-MCI and healthy subjects [ 73 ], whereas previous research showed a progressive deterioration in these faculties becoming observable even in individuals with MCI [ 86 ]. Further evidence from factorial analyses revealed the critical role of verbal knowledge in predicting DM performances; in contrast, reading speed emerged as the most predictive measure deriving from the administration of a single test [ 84 ].…”

Feeling valued versus abandoned: Voices of persons who have completed a cognitive assessment

“…A purposeful sampling method was chosen to capture experiences which could enhance the knowledge of the field (Polit & Beck, 2017). Thorne (2016) (Folstein et al, 1975) score ≥15p as described by Stormoen et al (2017) as a cutoff point for informed consent and ability to converse and communicate in Swedish or English.…”

The marriage of psychology and law: testamentary capacity

“…A recent study investigated the predictive ability of 27 cognitive tests in classifying capacity to consent to medical treatment using a vignette paradigm (Stormoen, Almkvist, Eriksdotter, Sundstr€ om, & Tallberg, 2014). Their sample included patients with Alzheimer's disease (AD), mild cognitive impairment (MCI) and healthy controls (HC).…”