Abstract
BACKGROUND: While severe fatigue is common in patients with diffuse glioma, no evidence-based treatment is currently available. The objective of this RCT was to evaluate the efficacy of blended cognitive behavioral therapy (bCBT) for severe fatigue. METHODS: Severely fatigued patients (Checklist Individual Strength, fatigue-severity subscale [CIS-fatigue] ≥ 35) with diffuse glioma and stable disease were randomized to 12 weeks of bCBT or a waiting list condition (WLC). The primary endpoint was fatigue severity 2 weeks after intervention. This Bayesian adaptive trial included prespecified interim analyses for efficacy at n = 40, 50, 60, 70, and 80. Secondary outcomes-health-related quality of life (HRQoL), anxiety, future uncertainty, and depression-were assessed at 2 and 12 weeks after intervention. RESULTS: The trial was stopped for efficacy at the first interim analysis. Of 47 patients randomized, 40 patients reached the primary endpoint (mean age 53 years, 47% female). The posterior probability that CIS-fatigue scores were lower with bCBT than with WLC was 99.94%, with a large standardized effect size (Cohen's d) of 1.12 [95% CI: 0.43-1.81]. At 2 weeks after intervention, 68% of patients were no longer severely fatigued after bCBT, compared to 24% in WLC. At 12 weeks follow-up, fatigue was still significantly lower in the bCBT group compared to WLC (d = 1.22). bCBT also demonstrated beneficial effects (d = 0.42-1.19) on anxiety, HRQoL, and future uncertainty. CONCLUSIONS: bCBT significantly reduces fatigue and improves anxiety and HRQoL in patients with diffuse glioma. These findings enable evidence-based supportive care strategies for reducing fatigue and enhancing HRQoL in this population.