Frailty in older adults: Implications for end-of-life care
ABSTRACTFrailty has important implications for the care needs of older adults and how those needs are met. By recognizing frailty and measuring it objectively, clinicians can better engage patients and their loved ones in difficult discussions about treatment plans and prognosis, and ultimately deliver better palliative care.
KEY POINTS
- Frail older adults are more susceptible to delirium, functional decline, impaired mobility, falls, social withdrawal, and death.
- Evaluating the health care needs of people who are frail requires assessment of their cognition, function, mobility, balance, and social circumstances, in addition to understanding their medical problems.
- When people are so frail that they cannot withstand interventions that can cause significant injury, such as surgery or chemotherapy, then appropriate end-of-life care should focus on maintaining their highest-order functions.
- End-of-life care can include curative treatments of some episodes if they threaten cognition, mobility, or function or cause pain and suffering, even in the context of an overall palliative care plan.
Tools for assessing frailty in people who are not yet disabled
Several tools exist to clinically assess frailty in people who are not yet disabled.
The FRAIL scale.12 The Geriatric Advisory Panel of the International Academy of Nutrition and Aging formulated a scale for measuring frailty as a “pre-disability state.” The FRAIL scale consists of five easily remembered items:
- Fatigue
- Resistance (inability to climb one flight of stairs)
- Ambulation (inability to walk one block)
- Illnesses (more than five)
- Loss of weight (> 5%).
Like the “reduced activity” criterion of the frailty syndrome mentioned above (in practical terms, described as the inability to do heavy household chores),13 the FRAIL scale seems to blur the distinction between disability (here, the inability to climb stairs or to walk a block) and “pre-disability,” to an uncertain end. It also seems to blend the notion of a state and a syndrome; these points will need to be clarified in due course.
The Tilburg Frailty Indicator14 was constructed around the multidimensional viewpoint of frailty, beyond disease or disability state, to identify frail community-dwelling older individuals. The first part of this two-part questionnaire consists of 10 questions on frailty determinants and medical comorbidities, while the second part contains physical, psychological, and social variables strongly associated with frailty, as well as information about disability in walking and balance. Interestingly, although it includes both social and physical factors, it does not include cognition.
The Clinical Frailty Scale was developed as a practical approach to assess frailty using physical and functional indicators of health and illness burden. The descriptors for this 7-point scale guide clinicians in quantifying the degree of frailty present. It ranges from 1 (very fit) to 7 (severely frail).7 The higher the score, the higher the risks of death or institutionalization. Even mild frailty is associated with a 50% 5-year mortality rate in community-dwelling older adults (Figure 1).8
The Edmonton Frail Scale,15 like the Clinical Frailty Scale, was developed to be practical and usable at the bedside. It is based on the following domains: cognition, general health status, functional independence, social support, medication use, nutrition, mood, continence, and functional performance.
In a community-based sample, the Edmonton Frail Scale compared favorably with the clinical assessment of geriatric specialists who completed a comprehensive evaluation (Pearson’s correlation coefficient 0.64, P < .001).15
FRAILTY AS A PROGNOSTIC INDICATOR
Using frailty scales to aid in prognostication can be useful to clinicians. Survival prognostication is inherently challenging in individuals with multiple comorbidities and variable trajectories of decline, but it remains a vital clinical skill for all clinicians. Framing these difficult discussions in the context of degree of frailty provides a unifying concept, beyond a single-system construct, for care providers, patients, and their loved ones.
Patients nearing the end of their lives need this kind of clarity and support. Regardless of their diagnoses, patients typically want to know when they are at high risk of dying, as do their families and caregivers. People in general look for such information so that they can align medical decision-making congruently with predicted prognosis.16,17 They also use it to plan for the final chapter of their life and their death.
The frailty index is strongly correlated with risk of death
The frailty index is strongly correlated with the risk of death, with a correlation coefficient greater than 0.95. As such, an individual’s frailty index score is considered an estimate of biologic age, which has greater correlation with associated morbidity and death than does chronological age.18,19 In the general population, more than 99% of people have a frailty index value of less than 0.7. As people approach this value, the chance of survival is greatly diminished; indeed, one report suggested that of those who have a frailty index value of more than 0.5 (based on a comprehensive geriatric assessment), 100% are dead by about 20 months later.20,21
In short, there is a limit to which deficits can be added before the system fails. In this sense, the frailty index is akin to the concept of physiologic reserve. Reserve is finite, and as a system loses redundancy it can no longer survive new stresses.
What does this information mean for individual patients?
Even so, prognostication for individual patients remains probabilistic. Any patient has a chance to improve, stabilize, worsen, or die. However, a patient can reach an upper limit of frailty. At that point, instead of accumulating another deficit, death is much more likely. Similarly, although improvement can happen, the chance of improvement is low, and the improvement is typically modest.
Framing survival possibilities in terms of the number of things that people have wrong with them and the chance of death or of change (and the extent of change) makes sense to physicians, patients, and families. Being able to do so offers a much greater opportunity for realistic discussions of the likely outcomes of medical care than the foreseeable scenario of a junior doctor asking a senior citizen, “If your heart stops, do you want us to save your life?”
Understanding prognosis in the face of not just disease but also frailty can also help us focus not on disease but on health consequences of illness. Can the person think? Walk? Care for herself or himself? Interact with others? These questions need to be considered when end-of-life decisions are being discussed.22
Since making predictions about survival is most challenging when multiple comorbidities are present, using the concept of accumulating deficits to better define the slope of decline can be very helpful when discussing “the road ahead” with patients and their families. Visually mapping out the slope of decline and how it is accelerating as conditions progress and deficits accumulate can aid in medical decision-making. Looking individually at the deficits themselves and associated markers of progression can also help with prognostic discussions.
For example, a patient with chronic obstructive pulmonary disease could very well be unaware of the progression and ultimately terminal prognosis of this disease. The slope of clinical decline can be initially shallow, with saw-tooth fluctuations from acute exacerbations that seemingly “resolve to baseline” when antibiotic and steroid courses are completed. Talking with these patients and their families about heralding markers, such as more hospitalizations and cognitive decline with acute exacerbations, can clarify the steepening slope of decline and the way comorbidities interact.
