The median age for someone to receive a cancer diagnosis is 67 years according to the Surveillance, Epidemiology, and End Results database and even higher for certain malignancies. For example, many gastrointestinal cancers are diagnosed in septuagenarians. With the advancing age and expanding waistlines of the US population, the number of patients seen at oncology clinics who have multiple chronic conditions is also expanding. Said Rowena Schwartz, PharmD, BCOP, director of oncology pharmacy at Johns Hopkins Hospital in Baltimore, Maryland, and president of the Hematology/Oncology Pharmacy Association, “We know that as patients age, there are more comorbidities; and as patients age, the instance of cancer increases, so it makes sense that those go together.”
Schwartz said elderly patients with comorbidities often have worse outcomes with anticancer therapies and said no one is certain why. “Is it because they have high comorbidities and they don’t tolerate treatments, or is it because we dose-modify to deal with the comorbidities? Is it because they don’t present until their disease is advanced because their cancer symptoms are confused with the comorbidities?” she asked. “We don’t know why. The data in comorbidities and the data in geriatrics are not really plentiful,” explained Schwartz.
The COPIT (Cancer in the Oldest: Prevalence, Related-Illnesses, and Treatment Modalities) study looked at records for 194,797 US military veterans aged >70 years with cancer (99.6% were men) to assess the rates of various comorbidities in this aged population. The researchers found that 70% had hypertension, >50% had hyperlipidemia, 40% had heart disease, 25% had diabetes, 21% had osteoarthritis, 17% were medically frail, 10% had depression, and 6% had dementia. Some patients fell into more than 1 of these categories.
A single-institution study by Wedding and colleagues found a high rate of comorbidity in adult patients with cancer in all age demographics. Comorbidities were severe in approximately three-quarters of the elderly patients compared with half of the younger patients. The rate of severe comorbidities was similar in the cohort of elderly patients without cancer (79%).
Schwartz said a 2010 literature review by Lee and associates looked at 34 studies and concluded that clinicians used chemotherapy less often or at lower doses for patients who had comorbidities, regardless of the type or stage of cancer. More than two-thirds (69%) of the 29 studies to report on overall survival found it was diminished in patients with cancer who had comorbidities. The prevalence, range of comorbid conditions, and their effects on treatment and outcomes point to the need for clinicians to consider comorbidities when caring for patients with cancer. Schwartz believes this is something that must be done on an individual basis, but also at the clinical trial level.
“There are no clinical trials that look at comorbidities and look at treatment in individual populations,” Schwartz said. “We may need to look at specific comorbidities in specific populations with specific types of disease.”
Monitoring patients with comorbidities involves more than asking questions at a follow-up visit. Schwartz prefers to telephone patients, particularly when prescribing anticoagulation therapies. “I like to do phone followups because you can do it every day and get a better picture.” That daily interaction is important for some of the highest risk patients because “people’s memories just don’t jive with what actually happens,” she said. This is especially true for elderly patients, who, weeks later, might not remember to tell their clinician about a symptom that seemed important at the time. Schwartz said monitoring an elderly patient with comorbidities also requires engaging the people in their lives who provide support. “Figure out where they live and who provides that overview of care.”