Cognitive impairment linked to worse survival in elderly with haematologic cancers
Cognitive dysfunction is associated with reduced survival in elderly patients with haematologic malignancies, a recent study has shown.
“Our results showed that cognitive impairment was prevalent among this group of patients, and impaired working memory was associated with worse survival after adjusting for age, comorbidities and disease aggressiveness,” the researchers reported. [JAMA Oncol 2018, doi: 10.1001/jamaoncol.2017.5674]
The prospective observational cohort study included 360 elderly patients aged ≥75 years who presented for initial consultation at the leukaemia, myeloma or lymphoma clinics of the Dana-Farber Cancer Institute in Boston, Massachusetts, US.
Screening revealed probable executive dysfunction in 127 patients (35.3 percent), while 62 patients (17.2 percent) were found to have probable impairment in working memory. Many patients who were robust in the frailty phenotype assessment were found to have cognitive impairment (24 of 104 patients [23.1 percent] with executive dysfunction; 9 of 104 [8.7 percent] with impaired working memory).
In the overall cohort, probable impairment in working memory was associated with shorter median survival (10.9 months vs 12.2 months for those without impairment; p<0.001). Impairment in working memory was also associated with decreased survival among patients with aggressive disease (p<0.001) and those with indolent disease (p=0.01).
After adjusting for age, disease aggressiveness and comorbidity, patients with impaired working memory were found to have worse survival (odds ratio [OR], 0.26) compared with their counterparts without impairment.
However, patients with executive dysfunction were found to have similar odds of survival compared with those without executive dysfunction (OR, 1.11) on multivariate analysis.
“Deficits in executive function were predictive of mortality only in a subset of patients undergoing intensive treatment,” the researchers noted.
In patients treated with intensive regimens, executive dysfunction and impaired working memory were both associated with decreased survival (p=0.03 and p<0.001, respectively). However, no association was found between cognitive impairment and decreased survival in patients who were untreated and those who underwent supportive or attenuated treatment.
“Cognitive impairment is associated with poor prognosis in patients with solid tumours. Our results suggest that the same is true for haematologic malignancies,” the researchers noted.
“Our data support the feasibility and potential utility of routine domain-specific screening for cognitive impairment among older patients with blood cancer,” they suggested. “Cognitive screening adds important information to standard frailty screening, since many patients who appeared to be robust may have had a degree of cognitive impairment that could affect their survival.”
“The median survival difference of greater than 1.3 months for patients with impairment in delayed recall was arguably small, but in oncology, new treatments have been approved for even smaller survival gains,” they added.
In the study, screening for executive dysfunction was performed using the Click-in-the-Box (CIB) test, while screening for impairment in working memory was based on the five-word delayed recall test.
“Clinic staff can easily be trained to administer both screening tests, which take only a few minutes,” said the researchers. “Further research should focus on tailored strategies to mitigate domain-specific cognitive dysfunction in older patients with haematologic malignancies.”