Evaluating fatigue during tyrosine kinase inhibitor treatment for chronic myeloid leukemia

This study aimed to investigate fatigue (tiredness) as a side effect of tyrosine kinase treatment in patients with chronic myeloid leukemia and its relationship to physical activity.  

This study concluded that identifying patients at risk of severe fatigue and working to reduce fatigue during treatment of CML should be a priority. 

Tyrosine kinase inhibitors (TKI) are a type of targeted therapy that can be used to treat chronic myeloid leukemia (CML). Fatigue is a common side effect of TKI treatment. The occurrence of TKI-induced fatigue remains uncertain and little is known about predictors of fatigue and relationship to physical activity.

This study involved 220 patients with CML treated with TKI therapy. These patients were compared to 110 people without CML. Patients completed an online questionnaire to assess fatigue severity and fatigue predictors.  

55.5% of CML patients experienced severe fatigue compared to 10.9% in the control group. Five predictors of fatigue were identified: age, female gender, additional medical conditions, the use of other medications known to cause fatigue, and lack of physical activity. 

Physical activity levels were also assessed for 7 days in 138 severely fatigued and non-fatigued CML patients. Monitoring of activity patterns confirmed that fatigued CML patients performed less physical activity (of both light and moderate to vigorous intensity) when compared to non-fatigued patients. Fatigued patients performed 1 hour less of physical activity per day and took 2000 fewer steps per day when compared to the non-fatigued patients. 

This study concluded that identifying patients at risk of severe fatigue and working to reduce fatigue during treatment of CML should be a priority. It was also concluded that fatigued patients performed less physical activity when compared to non-fatigued patients.  

This study could not determine that lack of physical activity is a risk factor for fatigue. More studies are needed.