Strategies for Managing Cancer-Related Fatigue, Impact on Cognitive Function

Cancer-related fatigue remains one of the most prevalent challenges for patients during and after treatment, often manifesting alongside significant cognitive changes. CancerNetwork® spoke with Yesne Alici, MD, at the 2026 American Psychosocial Oncology Society Annual Meeting about the intricate link between fatigue and brain fog, noting how physical exhaustion can directly hinder processing speed and executive function.

Alici emphasized that by identifying and treating specific drivers of fatigue—such as iron deficiency anemia, treatment-related weight loss, or sleep disturbances—clinicians can effectively mitigate cognitive deficits. From addressing nocturia in bladder cancer to screening for sleep apnea in head and neck cancer, this discussion highlighted why a comprehensive assessment of a patient’s sleep and energy levels is essential for restoring cognitive clarity.

Alici is vice chair of Clinical Operations in the Department of Psychiatry and Behavioral Services, clinical director, associate attending psychiatrist, and medical director of the Biobehavioral Health Clinic at Memorial Sloan Kettering Cancer Center.

Transcript:

Cancer-related fatigue is highly prevalent in patients who are going through cancer treatments and afterwards, and fatigue and cognitive changes have a lot of overlapping characteristics. Fatigue makes patients slow down [and] it impacts their processing speed. It also can cause a similar picture to the brain fog. There are ways to help manage fatigue, or there are ways to help manage the common ideologies for cancer-related fatigue. By managing those, we can have a positive impact in the cognitive impairment that patients experience because of their cancer treatments. Let’s say if the fatigue is from an iron deficiency anemia that happens because of the treatment. Or if the fatigue is from the weight loss that happened because of the nausea, vomiting, chemotherapy, [adverse] effects, those things can be acted upon. They can be treated and intervened, so that the fatigue improves, and therefore the cognitive deficits improve.

The other thing we should highlight is the sleep disturbances. Now, sleep disturbances can happen due to a couple of different reasons. In the cancer setting, this could be anxiety, depression, it could be patient receiving, let’s say, bladder cancer treatments, and they’re having to go to the bathroom multiple times throughout the night, or the patient is experiencing diarrhea and they’re having to go to the bathroom multiple times, and they’re waking up. Patients with head and neck cancer experience significantly increased rates of sleep apnea that can cause sleep disturbances. It’s essential to ask about the characteristics of the sleep in patients who are presenting with cognitive impairment in the cancer setting, so that we can find out why these sleep disturbances are happening, and as a result of that, [patients] are experiencing memory disturbances, attentional disturbances, or processing speed issues or executive dysfunction as a result of the sleep disturbances. Once we fix the sleep, cognition will improve.

Reference

Alici Y. Mind the gap: untangling cancer-related cognitive impairment from dementia-diagnostic clarity in cognitive crossroads. Presented at the 2026 American Psychosocial Oncology Society Annual Meeting; New Orleans, LA; March 18-20, 2026.