Comorbidity
The typical older oncology patient has multiple noncancer conditions (comorbidities), and the complexity of comorbidity increases with age.[32] Accordingly, older patients are more likely to take multiple medications, to suffer significant impairments and symptomatic limitations related to their comorbidity, and to have less functional reserve in the face of the stresses related to the primary cancer and its treatment.[33-37] Despite widespread recognition that comorbidity is clinically relevant, the application of this concept is more complex in daily practice.
Comorbidity is frequently considered in terms of an index, or as the total number of noncancer conditions, and even a simple method of counting chronic conditions provides an estimation of life expectancy among patients with cancer.[38] Other commonly used tools include the Charlson Comorbidity Index, which weighs the number and severity of comorbid medical conditions as well as the age of the patient.[39,40] The Adult Comorbidity Evaluation–27 weighs each comorbid condition according to level of severity and then generates an overall comorbidity score based on the severity of the highest-rank ailment.[41] Both of these comorbidity indexes can be abstracted from a chart review.[39,40] Other comorbidity indexes use patient self-report to capture illnesses, age, and physical function in order to stratify the risk of mortality among community-dwelling older adults.[42]
While these tools are helpful when the goal is estimation of life expectancy or risk adjustment across hospitals or providers, it is unlikely that a single index will capture the complexity of a heterogeneous population of older adults across different types of cancer.[43-45] More importantly, combining conditions into a single score fails to capture the clinical complexities of caring for adults with multiple chronic conditions or the variation in the clinical relevance of these conditions across patients.[38,46,47] Clinical decision-making in older persons with cancer would benefit from a better understanding of the impact that specific conditions, as well as combinations of conditions, have on patient outcomes.
Nutrition/Weight Loss
Screening for malnutrition is warranted in older adults with cancer. Among community-dwelling older adults in the general population, the prevalence of malnutrition is low (mean: 2%, range: 0%–8%), although the risk of malnutrition is high (mean: 24%, range: 8%–76%). However, studies of hospitalized older adults found a mean prevalence of malnutrition of 23% (range: 1%–74%).[48] Weight loss and poor nutritional status are associated with poorer response to therapy and decreased survival.[49,50]
Several tools can provide nutritional screening. One that has been well validated to correlate with clinical assessment and objective indicators of nutritional status is the Mini Nutritional Assessment (MNA), which evaluates dietary intake, anthrometrics, self-perceived nutrition and health, and a general assessment of lifestyle, mobility, medications, and cognition.[51] The MNA–Short Form (MNA-SF) was validated to employ a two-step screening process, with lower scores indicating higher risk for malnutrition. If the score is ≥ 12, the patient is at low risk for malnutrition and no further assessment is needed at that time. If the score is ≤ 11, the rest of the MNA should be completed to determine whether the patient is malnourished or is at risk of becoming so, and the patient should be referred to a dietitian for assistance.[48]
