Prevalence of the Inability to Give Informed Consent in the Elderly Orthopaedic Trauma Population

Abstract

Purpose: Despite the fact that fractures are a leading cause of morbidity in the elderly, a study of the prevalence of the inability to give informed consent in the elderly orthopaedic trauma population has, to the best of our knowledge, not been performed. In addition, the condition of mild cognitive impairment (MCI) has become increasingly recognized since the introduction of the Montreal Cognitive Assessment (MoCA). By simultaneously determining capacity for consent (by clinician gestalt – the gold standard) and degree of cognitive impairment (by utilizing the MoCA), we hope to better understand the relationship between the ability to consent and MCI as well as the specific components of cognition that may allow for decision-making capacity (DMC). Methods: This prospective study was carried out at Brigham and Women's Hospital (BWH). English and Spanish speaking patients older than 65 who were admitted for orthopaedic injury requiring surgical management were included in the study. Those who had previously known dementia and delirium were excluded from the study, as well as those who were unable to communicate. (NB: A recent IRB amendment has now allowed us going forward to approach certain patients with known dementia and delirium). Attending physicians determined whether or not a patient had DMC. Independently, a research staff member administered the confusion assessment method (CAM) short form to screen for delirium and the MoCA to screen for cognitive impairment. Various other background data were obtained retrospectively. Results: While the prevalence of the inability to give informed consent cannot be determined since the project is still actively recruiting patients, we hypothesize that this prevalence is at least 15.6%. While patients with DMC had various demographic data characteristic of the elderly orthopaedic trauma population, 81.8% had an abnormal total MoCA score. Participants generally scored worse on tasks assessing for certain cognitive domains, such as visuospatial/executive function tasks (mean score: 46.7%) and the delayed recall task (mean score: 40%). The vast majority of participants (90.5%) who struggled with the delayed recall task were, however, able to remember additional words with category and/or multiple choice clues. None of the participants had a positive screen for delirium. Conclusions: Mild cognitive impairment at the time of consent appears not to preclude a patient from having DMC. Although the relationship between cognitive ability and DMC remains not well understood, further conclusions regarding early cases of dementia should be studied going forward. Deficits in certain domains of cognitive thinking may be correlated with an inability to give informed consent, although a comparison of testing results between patients with versus without DMC will be required to further understand this idea.