Capacity refers to a patient’s ability to make a medical decision and is rooted in both ethical principles and personal rights. Every recommendation made by a physician in a clinical encounter is based upon a foundation that is carefully informed by autonomy and beneficence. There is an implicit assumption that the patient is cognizant of a situation and in agreement with the physician. However, there is a need to be wary of this almost automatic assumption. A comprehensive review by Sessums et al. (
1) of 43 prospective studies that evaluated medical decision-making capacity for treatment decisions revealed that up to 26% of 816 medical inpatients lacked decisional capacity and clinicians identified only 42% of affected patients. Therefore, it is crucial that every physician understands the importance of capacity and possesses the ability to discern it.
Although all physicians are legally permitted to determine capacity, an increasing number of physicians seek psychiatric consultation (
2). Capacity has become the "bread and butter" of consultation-liaison psychiatry and accounts for about 25% of all consults (
3). The reasons for this increase are unclear. It may be due to fear of litigation or due to increased audits of work via performance indicators. Inpatient physicians feel an increased responsibility to treat and ensure safety while concurrently respecting autonomy. However, many physicians hesitate to make a decision about a patient’s capacity and are unfamiliar at times with the criteria and clinical nuances to consider when assessing capacity. A survey of nearly 400 consultation-liaison psychiatrists and geriatricians determined that the most common misconception is that capacity is global, when in fact it is specific to a particular question (
4).
In their seminal work on capacity published in 1988, Appelbaum and Grisso (
5) proposed four criteria for the evaluation for capacity: the patient’s ability to appreciate the current situation, the patient’s ability to understand information relevant to the decision, the patient’s ability to use or weigh that information as part of the process of making the decision (i.e., rational manipulation of the information), and the patient’s ability to communicate a consistent choice. Failure in any one of these criteria implies that the patient lacks capacity to make a treatment decision. In addition to these four criteria, the patient’s previous behaviors and decision-making patterns should be considered. Of note, these assessments pertain to the time of evaluation and have no bearing on past or future decisions. Thus capacity is time sensitive and dynamic. Additionally, each capacity assessment applies to a single decision, meaning that a patient may have capacity to make one decision but lack capacity to make another.
Assessing capacity becomes further convoluted when assessing for capacity in patients with neurocognitive disorders. Studies show that these patients demonstrate significant impairment in abilities to consent, such as appreciation, reasoning, and understanding of clinically relevant information (
6). The delicate balance of autonomy versus beneficence must be weighed carefully. Beyond the duty to respect patient autonomy, there is just as much a duty to protect those who have diminished capacity from making potentially harmful decisions. If this commitment is neglected, there is a "risk of abandoning patients to their rights" (
7).
This raises the question: What is the best way to evaluate patients with diminished capacity as a result of a neurocognitive disorder? The Capacity to Consent to Treatment Instrument and standardized neuropsychological tests—such as Mini-Mental State Examination; Dementia Rating Scale, 2nd edition; Wechsler Memory Scale; and Geriatric Depression Scale—are often used in patients with neurocognitive disorders and have been shown to be predictive of impaired capacity in patients with mild cognitive disorders (
6).
This case report highlights the subtle intricacies of assessing capacity by describing a notable case involving a severely demented patient.
Case
"Mr. M" is an elderly male in his 90s with an extensive medical history, including Parkinson’s disease, chronic lymphocytic leukemia, atrial fibrillation, hypertension, and diabetes, who presented to the emergency department for seizure. Upon admission, he wished to be on full code status, at which point his overseeing physician expressed concerns of the potential risks associated with cardiopulmonary resuscitation, intubation, and mechanical ventilation in his condition. Psychiatry was consulted to assess his capacity to decide code status.
On interview, Mr. M did not know he was admitted for a seizure, even though he was able to recall the uncontrollable convulsions. He denied any other medical history, only to later confirm each of his various illnesses when prompted, with the exception of leukemia, which he continuously denied. His mental status exam was positive for resting tremor in his right hand and orientation to current year and president but not to date or month. The Montreal Cognitive Assessment (MOCA) score was 13 out of 26 suggesting the presence of dementia. Although MOCA is typically scored out of 30, we omitted the cube and clock drawings from the total score because of the patient’s difficultly writing with severe tremor. He scored full points in the naming test and the attention section, which includes reading a list of digits, letter "A" tapping, and spelling "t-a-b-l-e" forwards and backwards (substituted for serial seven subtractions).
When asked about his code status, Mr. M immediately replied, "I told her to bring the machine, start my heart up." He acknowledged understanding and approval of the various risks of undergoing a full code at his age and elaborated that his daughter was to make any final decisions of life support if he was unable to. Several hours later, the consult team met with the patient once more to confirm his understanding of the initial discussion, with an emphasis on asking in an open-ended manner. Mr. M was able to again explain the various sequelae and explain associated risks, including intubation, fractured ribs, and failure of the code attempt. Ultimately, this code status was maintained throughout his hospital course.
Discussion
Capacity in circumstances of impaired cognition is not always clear. This has prompted efforts to develop standardized measures of capacity (
8). However, these scales do not always account for the complexities in cases. Therefore, clinicians should be familiar with the criteria to evaluate capacity and be exposed to unique cases to guide them in challenging scenarios.
The consulting physician asked for an assessment of capacity to decide code status rather than capacity for medical decisions in general. Assessments of capacity apply to a single decision wherein a patient may have capacity for one decision but not another. In this case, the patient did not have the capacity to make decisions regarding the treatment of his various medical conditions. For example, he was unable to appreciate that his current admission was secondary to a seizure and was also unable to rationally link that having a convulsion meant that he had had a seizure, and he denied having any medical illness. This suggests a severe lack of appreciation for his current situation and its consequences. This was contrasted by the patient’s consistent choice and the clear understanding of a full code status as well as the risks. It must be concluded that this patient had the capacity to decide code status, distinct from his capacity to make medical decisions. Although the primary team had asked about medical decision-making capacity, the psychiatry consult team came to two different conclusions for two separate questions.
A sliding-scale model in decision-making capacity is also critical to address the nuances of this situation. The model prevents a blanket standard for all capacity decisions. It instead requires an increasingly stringent standard as the consequences of a patient’s decision become riskier (
9). The least stringent standard would apply to medical decisions that are relatively harmless and within the patient’s best interest, whereas the most stringent standard would apply to a decision that is objectively dangerous and contradicts professional rationale.
For our patient who desired full code status, the degree of understanding required was low. In contrast, had he been requesting to change from full code to do not resuscitate (DNR) the threshold would have been higher. Similarly, for our patient, who was nearing the end of life, the level of understanding needed to change from full code to DNR would differ dramatically from that of a young healthy patient attempting the same code status change. Thus, it is imperative to assess risk that would result from a decision. The threshold to demonstrate understanding can change for the same decision on a case-by-case basis.
This case also highlights the distinctive challenge of assessing capacity in a patient with dementia. Capacity to consent in patients with dementia is reduced, compared with controls; the most significant impairments are in understanding, followed by reasoning and appreciation (
10). Assessments are further complicated by cognitive fluctuations, which refer to spontaneous alterations in cognition, attention, and arousal. This common occurrence in dementia can render drastically different results based on the timing of an assessment (
11). Although dementia patients typically express a clear treatment choice, many struggle to demonstrate understanding and reasoning (
12). Physicians can maximize capacity assessments with dementia patients by minimizing distractions, simplifying and breaking up medical information into small sections, and providing corrective feedback on misunderstood information (
12). Capacity of these patients should be reassessed periodically for each distinct medical decision.
Ultimately, the determination of patient capacity can have drastic implications. It is not only the clinician’s moral and legal responsibility to address capacity, but doing so will also improve the physician-patient relationship. A thorough understanding of capacity, including its choice-specific, nonglobal nature and temporal boundaries, is imperative. This is especially important because many physicians hesitate to assess capacity and seek psychiatric consultation. Therefore, education and exposure to unique cases such as this will allow clinicians to confidently make appropriate decisions regarding patient capacity.
Key Points/Clinical Pearls