Risk factors for fatigue severity in primary brain tumor patients

In addition to neurologic symptoms, fatigue is commonly reported in patients with primary brain tumors during radiation therapy and in long-term survivors of low-grade brain tumors. Other factors have not been explored. The aim of this study was to identify demographic and clinical factors that predict fatigue severity and to evaluate the association of fatigue with other symptoms throughout the disease trajectory.

Two hundred one patients with primary brain tumors completed the M. D. Anderson Symptom Inventory-Brain Tumor Module and a demographic checklist. Clinical data, including treatment, tumor grade, and performance status, were also collected. Correlations among fatigue and other recorded symptoms were evaluated. Logistic regression modeling was performed to evaluate factors associated with fatigue severity.

Fatigue severity was associated with symptoms including pain, drowsiness, distress, difficulty sleeping, and weakness as well as overall symptom severity and interference. Poor performance status (Karnofsky scale) (odds ratio [OR], 5.73; P = .001), female sex (OR, 2.48; P = .005), and disease status (OR, 2.20; P = .013) were the strongest predictors of fatigue. Severity of fatigue for women was primarily predicted by disease status (OR, 3.33; P = .01) For men, antidepressant use (OR, 4.43; P = .013) in addition to opioids (OR, 3.46; P = .017) and performance status (OR, 12.47; P = .0001) predicted fatigue severity.

Fatigue should not be considered a solitary symptom with 1 root cause, but a complex symptom related to the severity of other symptoms and potentially having various etiologies. Future studies should consider these factors in planning interventions and assessing response.