Predictors of persistence of post-chemotherapy symptoms among survivors of solid tumor cancers

Context: Late or residual symptoms diminish quality of life for many cancer survivors after completion of treatment. Objectives: Examine risk factors associated with persisting symptom burden after chemotherapy and the lack of symptom improvement over time. Methods: Survivors who completed curative-intent chemotherapy within two years for solid tumors were enrolled into a symptom management trial. There were 375 survivors with two or more comorbid conditions or one comorbid condition and elevated depressive symptoms (pre-defined risk factors in the trial design) who received interventions and 71 survivors without these risk factors who did not receive interventions. For all survivors, symptoms were assessed at intake, 4, and 13 weeks and categorized as mild, moderate, or severe based on the interference with daily life. The probabilities of moderate or severe symptoms and symptom improvement were analyzed using generalized mixed-effects models in relation to comorbidity, depressive symptoms, age, sex, race/ethnicity, employment, time since chemotherapy completion, and physical function. Multiple symptoms were treated as nested within the survivor. Results: Moderate or severe symptoms at baseline and the lack of improvement over time were associated with younger age and lower physical function over and above a greater number of comorbidities and elevated severity of depressive symptoms. Conclusion: Risk factors identified in this research (younger age, lower physical function, greater comorbidity, and higher depressive symptoms) can be used to allocate resources for post-treatment symptom management for cancer survivors in order to relieve symptoms that do not necessarily resolve with time.