Cancer-related cognitive impairment (CRCI) has not been objectively assessed in chronic lymphocytic leukemia (CLL). It is currently unclear how much of CRCI is attributable to disease, treatment, or both. We used CLL as a novel model to study the differential roles of disease and treatment in CRCI. One hundred and fifty CLL patients (100 treatment-naïve and 50 chemotherapy-treated) including 84 patients with higher-risk of CLL progression completed objective neuropsychological tests. Sociodemographic-adjusted linear regression models examined cognitive outcomes in relation to risk and treatment. Higher-risk patients recalled two fewer words on a memory task (β = -1.8, 95%CI -3.3,-0.3) and took 15 s longer on an executive function task (β = 15.4, 95%CI 3.1, 27.6) than lower-risk patients, independent of treatment. Treated patients reported greater cognitive difficulties than treatment-naive patients (β = -6.1, 95%CI -10.1, -2.2) but did not perform worse on objective measures. Higher-risk patients experienced impairments in executive function and memory suggesting that disease biology contributes to CRCI independent of treatment.
Keywords: Chronic lymphocytic leukemia; chemotherapy; cognitive impairment; treatment naïve.