The Power of the Placebo in Symptom Management
- N. Lynn Henry⇑ and Jennifer J. Griggs – Author Affiliations University of Michigan Comprehensive Cancer Center, Ann Arbor, MI Corresponding author: N. Lynn Henry, MD, PhD, University of Michigan Comprehensive Cancer Center, 1500 East Medical Center Dr, Med Inn Building C450, Ann Arbor, MI 48109-5843; e-mail: firstname.lastname@example.org.
“Why some patients respond to a therapy that is intended to be inactive, known as the placebo effect, has been extensively studied. The placebo response is related to the expectations and perceptions of the treated patient and can be heightened if there is a supportive patient-provider relationship. Conversely, the placebo effect can be abolished if a patient is told that the intervention is ineffective. Functional imaging studies have demonstrated increased activity in reward centers and alterations of dopaminergic pathways in the brain in patients treated with placebos, suggesting that they can exert true physiologic responses. However, in blinded clinical trials, in which patients do not know whether they are receiving the active drug or a matching placebo, the placebo effect is often less apparent.
Despite this observation, the finding of a substantial placebo effect is not uncommon in clinical trials investigating the management of symptoms.16–18 Placebo response rates have been as high as 30% to 50% in studies of pharmacologic management of cancer treatment—emergent toxicities, including vasomotor symptoms, fatigue, and neuropathy. Similar effects from placebo have also been found in studies of nonpharmacologic interventions, including acupuncture for pain. Therefore, when making decisions about how to manage symptoms, it is imperative to base those decisions on results of placebo-controlled, randomized trials of therapies…and not solely on the results of uncontrolled trials….”