How do colorectal cancer and chemotherapy affect cognitive ability?

This study investigated the associations between colorectal cancer, chemotherapy and cognitive impairment. The authors concluded that colorectal cancer patients had higher levels of cognitive impairment than healthy controls. Chemotherapy was not associated with an increased risk of cognitive impairment.

Cognitive impairment can cause problems in memory, thinking and reasoning. Previous studies have found cognitive impairment in patients with certain types of cancer. However, few studies have investigated cognitive impairment in colorectal cancer (CRC) patients. The effect of chemotherapy on cognitive impairment is unknown. Understanding these associations will help doctors make informed treatment choices.

This study examined whether CRC patients experienced cognitive impairment. The effect of chemotherapy was also investigated. 289 patients with localized CRC took part. In addition, 73 patients with metastatic/recurrent CRC (cancer that has spread or returned despite treatment) participated. 72 healthy controls (HCs, people without cancer, used for the sake of comparison) also participated. At the start of the study, participants completed questionnaires focusing on cognitive function, fatigue, quality of life, and anxiety/depression. Tests were repeated after 6, 12, and 24 months.

At the beginning of the study, 43% of  patients with localized CRC showed cognitive impairment, compared  to 15% of healthy controls. After 12 months, 46% of localized CRC patients had experienced cognitive impairment, compared to 13% of HCs. Chemotherapy did not have a significant effect. Cognitive impairment was similar in patients with localized and metastatic CRC. Attention, memory and verbal learning were some of the areas most affected.

32% of participants who received chemotherapy experienced cognitive symptoms at 6 months, compared to 16% of those who had not. After 12 months there was no significant difference. Patients who received fluoruracil (Oncofluor, Fluorblastin) in addition to oxaliplatin (Eloxatin) experienced higher levels of cognitive impairment compared to patients who received oxaliplatin alone.

The authors concluded that CRC patients had higher levels of cognitive impairment than healthy controls. Chemotherapy was reported to have no effect on cognitive impairment.

It is still unknown why CRC patients experience higher levels of cognitive impairment than healthy controls, only that there is an association.

Consult our doctor if you are concerned about your risk of cognitive impairment.