Purpose: Cancer-related fatigue is a prevalent, debilitating condition that can persist for months or years after treatment. In a single-arm clinical trial, the feasibility and safety of a time-restricted eating (TRE) intervention were evaluated among cancer survivors, and initial estimates of withinperson change in cancer-related fatigue were obtained.
Methods: Participants were 4-60 months post-cancer treatment, were experiencing fatigue (≥ 3 on a scale 0-10), and were not following TRE. TRE entailed limiting all food and beverages to a self-selected 10-h window for 14 days. Participants reported their eating window in a daily diary and completed the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F), Brief Fatigue Inventory (BFI), and symptom inventory pre- and post-intervention. This study was pre-registered at clinicaltrials.gov in January 2020 (NCT04243512).
Results: Participants (n=39) were 61.5 ± 12.4 years old and 1.8 ± 1.3 years post-treatment; 89.7% had had breast cancer. The intervention was feasible in that 36/39 (92.3%) of participants completed all questionnaires and daily diaries. It was also safe with no severe adverse events or rapid weight loss (average loss of 1.1 ± 2.3 pounds, p=0.008). Most adhered to TRE; 86.1% ate within a 10-h window at least 80% of the days, and the average eating window was 9.33 ± 1.05 h. Fatigue scores improved 5.3 ± 8.1 points on the FACIT-F fatigue subscale (p<0.001, effect size [ES]=0.55), 30.6 ± 35.9 points for the FACIT-F total score (p<0.001, ES=0.50), and -1.0 ± 1.7 points on the BFI (p<0.001, ES=-0.58).
Conclusion: A 10-h TRE intervention was feasible and safe among survivors, and fatigue improved with a moderate effect size after two weeks.
Limitations: This was a single-arm study, so it is possible that expectation effects were present for fatigue outcomes, independent of effects of TRE per se. However, this feasibility trial supports evaluation of TRE in randomized controlled trials to address persistent cancer-related fatigue.