Age is a well recognized risk factor for cancer development. The population of older Americans is growing, and by 2030, 20% of the US population will be aged ≥ 65 years.1 While 25% of all new cancer cases are diagnosed in people aged 65 to 74 years, more than half of cancers occur in individuals aged ≥ 70 years, with even higher rates in those aged ≥ 75 years.2 Although cancer rates have declined slightly overall among people aged ≥ 65 years, this population still has an 11-fold increased incidence of cancer compared with that of younger individuals.3 With a rapidly growing older population, there will be increasing demand for cancer care.
Treatment of cancer in older individuals often is complicated by medical comorbidities, frailty, and poor functional status. Distinguishing patients who can tolerate aggressive therapy from those who require less intensive therapy can be challenging. Age-related physiologic changes predispose older adults to an increased risk of therapy-related toxicities, resulting in suboptimal therapeutic benefit and substantial morbidity. For example, cardiovascular changes can lead to reduction of the cardiac functional reserve, which can increase the risk of congestive heart failure. Similarly, decline in renal function leads to an increased potential for nephrotoxicity.4 Although patients may be of the same chronologic age, their performance, functional, and biologic status may be quite variable; thus, tolerance to aggressive treatment is not easily predicted. The comprehensive geriatric assessment (CGA) may be used as a global assessment tool to risk stratify older patients prior to oncologic treatment decisions.5
Health care providers (HCPs), including physician assistants, nurse practitioners, clinical nurse specialists, nurses, and physicians, routinely participate in every aspect of cancer care by ordering and interpreting diagnostic tests, addressing comorbidities, managing symptoms, and discussing cancer treatment recommendations. HCPs in oncology will continue to play a vital role in the coordination and management of older patients with cancer. However, in general, CGA has not been a consistent part of oncology practices, and few HCPs are familiar with the benefits of CGA screening tools.
What Is Geriatric Assessment?
Geriatric assessment is a multidisciplinary, multidimensional process aimed at detecting medical, psychosocial, and functional issues of older adults that are not identified by traditional performance status measures alone. It provides guidance for management of identified problems and improvement in quality of life.6 CGA was developed by geriatricians and multidisciplinary care teams to evaluate the domains of functional, nutritional, cognitive, psychosocial, and economic status; comorbidities; geriatric syndromes; and mood, and it has been tested in both clinics and hospitals.7 Although such assessment requires additional time and resources, its goals are to identify areas of vulnerability, assist in clinical decisions of treatable health problems, and guide therapeutic interventions.6 In oncology practice, the assessment not only addresses these global issues, but also is critical in predicting toxicity and survival outcomes in older oncology patients.
Components of CGA
Advancing age brings many physiologic, psychosocial, and functional challenges, and a cancer diagnosis only adds to these issues. CGA provides a system of assessing older and/or frail patients with cancer through specific domains to identify issues that are not apparent on routine evaluation in a clinic setting before and during chemotherapy treatments. These domains include comorbidity, polypharmacy, functional status, cognition, psychological and social status, and nutrition.8
Comorbidity
The prevalence of multiple medical problems and comorbidities, including cancer, among people aged > 65 years is increasing.9 Studies have shown that two-thirds of patients with cancer had ≥ 2 medical conditions, and nearly one quarter had ≥ 4 medical conditions.10 In older adults, common comorbidities include cardiovascular disease, hypertension, diabetes mellitus, and dementia. These comorbidities can impact treatment decisions, increase the risk of disease, impact treatment-related complications, and affect a patient’s life expectancy.11 Assessing comorbidities is essential to CGA and is done using the Charlson Comorbidity Index and/or the Cumulative Illness Rating Scale.12