Cognitive Function of Older Patients Receiving Adjuvant Chemotherapy for Breast Cancer: A Pilot Prospective Longitudinal Study

Abstract
OBJECTIVES: To report on the longitudinal cognitive functioning of older women receiving adjuvant chemotherapy for breast cancer. DESIGN: Neuropsychological and functional status testing were performed before chemotherapy and 6 months after chemotherapy. SETTING: Cancer center. PARTICIPANTS: Thirty‐one patients aged 65 and older with Stage I to III breast cancer. Of the 31 patients enrolled, three refused posttesting, and 28 were evaluable. MEASUREMENTS: The following domains of cognitive function were examined: attention; verbal memory; visual memory; and verbal, spatial, psychomotor, and executive functions. RESULTS: Participants had a mean age of 71 (range 65–84): 39% Stage I, 50% Stage II, and 11% Stage III. The number of scores 2 standard deviations (SDs) below the norm were calculated for each patient before and 6 months after chemotherapy; 14 (50%) had no change, 11 (39%) worsened, and three (11%) improved (P=.05). Seven patients (25%) experienced a decline in cognitive function, defined as a 1‐SD decline from pre‐ to posttesting in two or more neuropsychological domains. Exploratory analyses revealed no significant difference between functional status, comorbidity, and depression scale scores and change in overall quality‐of‐life scores before and after chemotherapy. CONCLUSION: In this cohort of older women receiving adjuvant chemotherapy, a subset experienced a decline in cognitive function from before chemotherapy to 6 months after chemotherapy. Further prospective study is needed to confirm these observations and to identify the subgroup at special risk.