Cognitive Function in Patients at Different Stages of Treatment for Colorectal Cancer: A Comparative Cross-Sectional Study.

OBJECTIVES: To compare subjective and objective cognitive functions among patients at the following three stages of treatment for colorectal cancer (CRC): new diagnosis (Group A), ≤2 years since chemotherapy completion (Group B), and >2 years since chemotherapy completion (Group C).

DATA SOURCES: A comparative cross-sectional approach was used in this study. The Functional Assessment of Cancer Therapy-Cognitive Function questionnaire and neuropsychological assessments were used to assess patients' subjective cognitive function, attention, memory, and executive functions. A total of 63 patients with stage I to III CRC were recruited from a medical center in northern Taiwan. We performed one-to-one-to-one propensity score matching to identify 36 individuals as eligible for this study. A generalized estimating equation was used to compare subjective and objective cognitive functions.

CONCLUSION: We observed no significant between-group differences in subjective cognitive function and objective performance in overall cognition and memory. Group B had significantly longer reaction time in attention and processing speed than did Group A. Adjuvant chemotherapy had significantly deleterious effects on attention and processing speed in patients with CRC. These cognitive symptoms last for approximately 2 years after the completion of chemotherapy.

IMPLICATIONS FOR NURSING PRACTICE: The early detection of cancer-related cognitive impairment is necessary for managing symptom distress. Future studies with a large sample size and longitudinal design may elucidate the trajectory of specific cognitive functions. Developing nursing interventions aimed at improving attention and executive function in patients with CRC are needed.