Honest placebo may improve fatigue in cancer survivors
Placebo pills, even when administered open-label, appear to significantly improve cancer-related fatigue (CRF) and fatigue-disrupted quality of life, according to a recent study.
“Although our results suggest that [open-label placebo (OLP)] may be a beneficial treatment for CRF, replication studies are needed, as well as studies exploring how OLP works, why and under what circumstances,” said researchers. “Furthermore, efforts should be undertaken to learn whether OLPs can be successfully applied to a range of [patient-reported outcomes (PROs)] in cancer and other population.”
The researchers randomized 74 cancer survivors to receive either two placebo pills twice-daily for 21 days (OLP; n=38; mean age 58.4±11.2 years; 72 percent female) or treatment as usual (TAU; n=35; mean age 56±12.4 years; 66 percent female). Improvements in the Fatigue Severity Index (FSI) scores were significantly better in the OLP vs TAU group (mean difference [MD], 12.47; 95 percent CI, 3.32–21.61; p=0.008). [Sci Rep 2018;8:2784]
Majority (73.6 percent) of the patients who received OLP showed a mean change above that of those who received TAU. That is, there is a 67.2 percent probability that an OLP recipient, picked randomly, will have a better change in FSI score than a randomly selected participant in the TAU group.
Score improvements in the Multidimensional Fatigue Symptom Inventory Short Form (MFSI-SF) were also significantly better in the OLP vs TAU groups (MD, 11.76; 4.66–18.86; p=0.002), indicating greater improvements in fatigue-disrupted quality of life.
In terms of effect sizes, 77.6 percent of the OLP participants had higher mean score changes relative to the TAU group.
“[O]ur results indicate participants taking an OLP experienced a 29-percent improvement in fatigue severity while fatigue-disruption on quality of life improved by 39 percent, with medium and large effect sizes, respectively,” said researchers.
Despite the interesting findings, the study has several limitations, such as the lack of blinding and a small sample size, both which affect the quality of conclusion.
“[W]hile our results are positive, OLP’s effects need to be confirmed by larger and more rigorous trials of longer duration among different conditions to explore the extent to which biological, social and behavioural factors might influence responses to OLPs,” said researchers.
During the exploratory follow-up phase, from days 28–49, 34 TAU participants were given OLP for 21 days. Significant improvements in FSI (MD, 11.38; p=0.001) and MFSI-SF (MD, 7.65; p=0.002) change scores were observed.
Notably, in the 37 participants originally randomized to OLP who agreed to an additional 21-day follow-up, FSI (p=0.619) and MFSI-SF (p=0.733) change scores did not significantly change after discontinuation, indicating no degradation in improvement.