New data revealed that elderly patients with blood cancers, such as leukemia and multiple myeloma, are likely to show signs of diminished cognitive functions, which could impact their survival (JAMA Oncol 2018; doi:10.1001/jamaoncol.2017.5674).
Given these findings, the authors suggest that screening for types of cognitive impairment may be beneficial for older patients with hematologic malignancies. By identifying patients with such impairments, oncologists can tailor their care instructions to meet the needs of each patient.
“As the population ages, cognitive impairment is likely to become increasingly common among patients with cancer, diseases that, to a large extent, are associated with aging,” noted the study's lead author, Tammy Hshieh, MD, MPH, Associate Physician at Dana-Farber Cancer Institute and Brigham and Women's Hospital, Boston, in a statement. “Mild changes in memory or thinking may not affect everyday activities, but they can come to the fore in times of stress and affect patients' abilities to care for themselves. We wanted to get a sense of the prevalence of certain types of cognitive impairment and whether they impact survival in older patients with hematologic cancers.”
As a geriatrician at Dana-Farber, Hshieh noticed that a fair amount of her patients with hematologic cancer were experiencing difficulties with memory. “So, I set out to determine what the significance [and] implications of cognitive impairment were for these patients,” she told Oncology Times.
In this prospective cohort study, investigators screened for frailty and cognitive impairment among patients who were 75 years of age or older and had a received a consultation at Dana-Farber for the treatment of leukemia, lymphoma, or multiple myeloma.
Patients were assessed for physical frailty and took standard screening tests for cognitive impairment in working memory and executive function, according to researchers.
A total of 360 patients agreed to undergo frailty assessment (232 men [64.4%] and 128 women [35.6%]; mean [SD] age, 79.8 [3.9] years), and 341 of those (94.7%) completed both cognitive screening tests, study authors reported.
“For cognitive impairment, we used the Clock-in-the-Box test and 5-word delayed recall test to assess for executive dysfunction and working memory problems, respectively,” Hshieh explained. “For frailty, we examined patients for robust, pre-frail, and frail status by Fried's frailty phenotype and Rockwood's Cumulative Deficit Model of Frailty.
“We examined the association between mortality (and frailty) and cognitive impairment in the specific domains of executive function and working memory,” she continued.
Thirty-five percent of the patients had probable impairment in executive function and 17 percent had probable impairment in delayed recall/working memory, according to study results. “This suggests fairly high prevalence of cognitive impairment in our patient population,” Hshieh noted.
Patients who showed impairment in either of these areas were more likely than others to be deemed physically frail or prone to become frail, researchers noted.
When examining whether cognitive decline impacted patient survival, investigators found the results varied depending on the area in which the decline occurred. Impairment in working memory was associated with increased overall mortality (10.9 months) compared to patients without impairment (12.2 months), Hshieh reported.
Additionally, researchers found that among patients undergoing intensive cancer treatment, median survival was lower for patients with impaired working memory as well as those with executive dysfunction.
Hshieh noted there are limitations to the study, including that patients came from a single tertiary care center; the high rate of intensive treatment offered to these patients is likely not representative of a community setting; and cognitive impairment was assessed by screening tools, not diagnostic neuropsychological/neurocognitive testing.
“These data suggest that domains of cognitive dysfunction may be prevalent in older patients with blood cancer and may have differential predictive value for survival,” study authors concluded. “Targeted interventions are needed for this vulnerable patient population.”
It is important to remember, Hshieh noted, that mild forms of cognitive impairment are not always obvious. Individuals with such an impairment may appear physically well and are able to maintain their daily routines. However, when under stress, such as chemotherapy, the impairment may become more pronounced.
Given the association between cognitive decline and shortened survival, screening among elderly patients with blood cancer is imperative to ensure treatment plans are adjusted accordingly.
“Patients with working memory problems may have difficulty remembering medication schedules or following multiple-step instructions,” Hshieh noted, in a statement. “They may be at risk of becoming dehydrated or not knowing what to do if they experience side effects of treatment.
“Counseling that acknowledges and anticipates the needs of such patients has a major role,” she continued. “It's important to educate patients about when to call their doctor about a problem, and when to make an appointment to be seen. It's also important for clinicians to take time to explain treatment options to impaired patients and their caregivers to ensure they make choices in line with their values and priorities.
“Our study underscores the need to identify patients with cognitive impairment in order to tailor treatment approaches to be most helpful,” Hshieh reiterated to Oncology Times. Next steps, she noted will include an examination of the “correlation between cognitive domain specific impairment with non-mortality outcomes particularly important to older patients, including hospitalization, length of stay, readmissions, delirium incidence, and functional decline.”
Catlin Nalley is associate editor.