Is Frailty the Geriatric Troponin?

Abstract

The incorporation of serum highly sensitive cardiac troponin (hs-cTn) testing into diagnostic strategies identifying persons with a high probability of an acute coronary event is effective for risk stratification of chest pain syndromes [1]. Similarly, in older adults, given the heterogeneity of health status based on chronologic age alone, various tools have been investigated for their utility as risk stratifiers [2].

Frailty is a familiar term in geriatric medicine. It describes a state of vulnerability causing an impaired ability to maintain homeostasis due to reduced physiologic reserve. Frailty is associated with disability, multimorbidity, cognitive impairment, institutionalization, and mortality [3]. Analogous to troponin testing, frailty assessment has been used to risk stratify older adults.

The utility of assessing frailty beyond the field of geriatrics has been carefully investigated in other areas, including surgery [4], general internal medicine, and several of its subspecialties. In the United Kingdom, the National Health Service (NHS) requires persons ≥ 65 to be assessed for frailty by their primary care providers [5].

Given the increasing interest and understanding of frailty, it is opportune to update its role in the care of selected older persons. The recent narrative review by Singh and colleagues summarizes the current range of frailty integration into various internal medicine subspecialties and highlights knowledge gaps to guide future research supporting its integration into clinical care. Across all subspecialties, the authors note a bidirectional association between particular diseases and frailty. Frailty assessment is integrated into the assessment of candidate patients for transthoracic aortic valvuloplasty, candidates for liver transplantation, and persons over 65 with malignancies [6-8]. They demonstrate that in various medical conditions, frailty is associated with impaired clinical status, poorer response to usual management, and increased risk of treatment-related toxicities.

Their findings support frailty as both a risk stratifier and prognosticator. In chronic obstructive pulmonary disease, frailty is associated with reduced exercise capacity, quality of life, and mortality [9]. In cardiology, frailty predicts cardiac events and adverse outcomes after invasive procedures [10]. In rheumatology, frailty is associated with organ damage, disability, and mortality [11]. In end-stage renal disease, frail patients on dialysis have a twofold increased risk of death [12]. In gastroenterology, frailty is a predictor of rehospitalization and mortality in inflammatory bowel disease [13]. In oncology, frail older adults demonstrate lower treatment tolerance, greater treatment discontinuation, increased health care use, shorter progression-free survival, and reduced overall survival [14]. In older persons living with HIV, frailty occurs at younger ages compared to HIV-negative persons and has a clear impact on healthspan [15].

Disease exacerbations also impact frailty assessment. This has been referred to as secondary frailty [16], the management of which focuses on the underlying disease process. Evaluation of frailty status up to 2 weeks prior to the onset of an acute intercurrent condition can be considered [3].

Although specific diseases may bring an individual to medical attention, frailty is a geriatric syndrome rather than a disease. Herein lies the crux of the challenge of frailty assessment and management. Diseases often have a known cause, recognizable manifestations, a predictable course, and established treatments. Geriatric syndromes, including falls, impaired mobility, cognitive decline, polypharmacy, sarcopenia, incontinence, and frailty, often have multifactorial etiology, an unpredictable clinical course, and less well-established treatments. In managing frailty, the goal becomes patient centric, with a focus on underlying contributors, symptoms, function, and quality of life. Furthermore, geriatric syndromes often coexist, likely because of shared biologic processes. Frailty may be considered as the canary in the coal mine heralding the presence of other geriatric syndromes, all of which contribute to functional decline [17].

How should we proceed? We must first decide the who, what, where, when, how, and why of frailty assessments.

Who should be screened? A universal age cutoff may not be appropriate in all subspecialties. While ≥ 65 years is the usual age cut-off for geriatrics (based on historical and not necessarily biological precedent), other services, namely surgical, initiate screening at 70–75 years [18]. In contrast, in HIV, frailty screening may begin at age 50 [19].

Where and when should we screen for frailty? Outpatient frailty assessment portends the greatest opportunity to modify care. Acute care frailty assessment has value, but may be less accurate and instead reflect the status of a patient with secondary frailty.

The operationalization of frailty diagnosis remains controversial. The authors document heterogeneity both in the prevalence of frailty and the associations between frailty and adverse outcomes, often due to differing methods of assessment. More than 12 distinct frailty measures are listed in Singh's Table 1, and the list is not exhaustive. More than 60 tools are available to identify frailty [5]. The lack of consensus on a single, unifying, reliable, and simple frailty metric remains an ongoing frustration, despite a call to achieve this goal over 10 years ago [20] and numerous attempts to do so. One could opine ad nauseam, but we support the view that frailty metrics be responsive to local needs, logistics, and resources. Ultimately, we cannot improve what we do not measure, and the opportunity for communication, collaboration, tracking, and quality improvement rests with a more universal measure of frailty. Recognized measures have advantages and disadvantages, and there is divergence in the identification of frail individuals when comparing frailty metrics [21]. However, clinical utility and the realities of busy clinical settings support using a measure that requires little training or specialized equipment, is brief, objective, and reliable. Lowering barriers to implementation will ultimately improve patient care. Ambiguity and lack of consensus are a hindrance to communication with health care providers beyond the field of geriatrics, and ideally, a more universal measure will support bridge building. We must make the right thing the easy thing.

Frailty measures with categorical results provide greater granularity than binary results. Mildly, moderately, and severely frail patients are distinguishable from one another, and the person with mild frailty may garner benefits from interventions which the severely frail patients may not. Indeed, the severely frail patient, regardless of how defined, may be moribund, and care may shift to focus on quality of life and what matters most.

Why screen for frailty? Singh and colleagues have demonstrated that frailty is common among all medical subspecialties and threatens a worse clinical status and course.

What do we hope to achieve by identifying frailty? For some clinical areas, an interdisciplinary approach based on the comprehensive geriatric assessment (CGA) improves outcome parameters [22]. For others, the evidence is less certain [23].

Once frailty is identified, the operationalization of the CGA may lie in local adaptation of the Geriatric 5M's framework: Mind, Mobility, Medications, Multicomplexity, and Matters Most. There is no universal guidance to establishing an interdisciplinary team to conduct the CGA. The range and number of care providers will depend on local resources and individual patient needs. The team will also differ based on the setting (e.g., out-patient or in-patient). A multidisciplinary team approach is increasingly common in diverse acute care medical settings, although its introduction in out-patient management of older adults in nongeriatric specialties lags behind. A geriatrics-based comanagement model based on the CGA has been initiated in an urban academic center, although evidence of its efficacy has not yet been published [24]. Unfortunately, the shortage of geriatricians limits the establishment of such services, and their participation may be reserved for particularly complex cases. Evidence supporting a virtual CGA framework is increasing and may be an option in specific situations [25].

Improved patient care and quality of life, achieved via a holistic and patient-centered approach, are among the motivations to adapt such an approach. Frailty may inform, support, improve function, minimize harm, and reduce disability. Identification of frailty is only beneficial if it results in a differential response that positively impacts patient care and outcomes. It must be stressed that a diagnosis of frailty should not lead to an ageist attitude of therapeutic nihilism.

Thus, to return to “Is frailty the geriatric troponin?” The paper by Singh and colleagues while informative and necessary, also spotlights the ground yet to be covered. Much remains uncertain in many of the subspeciality summaries. There is limited evidence supporting how frailty identification leads to practice change to improve patient-relevant outcomes and quality of life in several of the specialities they review, but there is consensus that diagnosing frailty is fundamental. The medical black humor notion of “if you don't take a temperature you won't find a fever” holds true for frailty.

This timely review highlights future opportunities to best determine how frailty should guide management. Interventional studies comparing frail individuals who have and have not received “targeted care” are needed [5]. Patients and all relevant care partners should be involved in the design and implementation of these studies, with a goal to promote patient-centric interventions. Singh and colleagues have provided a vital update of this field. Although not discussed in their review, there is growing awareness of frailty in low- and middle-income countries, which will warrant future research and planning considerations for health care delivery in these regions. This momentum may serve as the impetus to obtain the necessary data to promote clinically meaningful and patient-relevant practice change.

J.M. and J.F. both contributed to the concept and preparation of the manuscript.

The authors have nothing to report.

The authors declare no conflicts of interest.

This publication is linked to a related article by Singh et al. To view this article, visit https://doi.org/10.1111/jgs.19268.