Research consent capacity varies with executive function and memory in Parkinson's disease

Abstract

Background: We examined the association between cognitive domains and research consent capacity in PD. Our hypothesis was that research consent capacity is best predicted by executive function.

Methods: A cohort of 90 PD patients and 30 healthy older adults were administered the MacArthur Competence Assessment Tool for Clinical Research, Dementia Rating Scale-2, and the MoCA. Experts classified patients as either "capable" or "not capable" of providing informed consent to participate in two clinical trials.

Results: MacArthur Competence Assessment Tool for Clinical Research Reasoning scores for both clinical trial types were most associated with executive functions and delayed recall. As scores on these domains improved, the odds of an expert rating of "capable of consent" increased.

Conclusions: These results extend our previous findings by demonstrating that memory and executive abilities appear closely associated with capacity when evaluated using either a structured interview or expert judgment of that interview.

Keywords: Parkinson's disease; capacity; cognitive impairment; decision making; informed consent.