Placebo effect of medication cost in Parkinson disease: a randomized double-blind
study.
Author(s): Espay AJ(1), Norris MM(2), Eliassen JC(2), Dwivedi A(2), Smith MS(2), Banks C(2),
Allendorfer JB(2), Lang AE(2), Fleck DE(2), Linke MJ(2), Szaflarski JP(2).
Affiliation(s): Author information:
(1)From the UC Neuroscience Institute, Department of Neurology (A.J.E., C.B.,
J.P.S.), and Department of Internal Medicine (M.J.L.), University of Cincinnati;
Gardner Family Center for Parkinson's Disease and Movement Disorders (A.J.E.),
Cincinnati; University of Cincinnati Center for Imaging Research (M.M.N., J.C.E.,
M.S.S., D.E.F.), OH; Division of Biostatistics and Epidemiology (A.D.), Texas
Tech University Health Sciences Center, El Paso; The Morton and Gloria Shulman
Movement Disorders Clinic and the Edmond J. Safra Program in Parkinson's Disease
(A.E.L.), University Health Network and the University of Toronto, Canada;
University of Alabama at Birmingham (J.B.A., J.P.S.); and Department of Veterans
Affairs Medical Center (M.J.L.), Research Service, Cincinnati, OH.
alberto.espay@uc.edu. (2)From the UC Neuroscience Institute, Department of
Neurology (A.J.E., C.B., J.P.S.), and Department of Internal Medicine (M.J.L.),
University of Cincinnati; Gardner Family Center for Parkinson's Disease and
Movement Disorders (A.J.E.), Cincinnati; University of Cincinnati Center for
Imaging Research (M.M.N., J.C.E., M.S.S., D.E.F.), OH; Division of Biostatistics
and Epidemiology (A.D.), Texas Tech University Health Sciences Center, El Paso;
The Morton and Gloria Shulman Movement Disorders Clinic and the Edmond J. Safra
Program in Parkinson's Disease (A.E.L.), University Health Network and the
University of Toronto, Canada; University of Alabama at Birmingham (J.B.A.,
J.P.S.); and Department of Veterans Affairs Medical Center (M.J.L.), Research
Service, Cincinnati, OH.
Publication date & source: 2015, Neurology. , 84(8):794-802
OBJECTIVE: To examine the effect of cost, a traditionally "inactive" trait of
intervention, as contributor to the response to therapeutic interventions.
METHODS: We conducted a prospective double-blind study in 12 patients with
moderate to severe Parkinson disease and motor fluctuations (mean age 62.4 ± 7.9
years; mean disease duration 11 ± 6 years) who were randomized to a "cheap" or
"expensive" subcutaneous "novel injectable dopamine agonist" placebo (normal
saline). Patients were crossed over to the alternate arm approximately 4 hours
later. Blinded motor assessments in the "practically defined off" state, before
and after each intervention, included the Unified Parkinson's Disease Rating
Scale motor subscale, the Purdue Pegboard Test, and a tapping task. Measurements
of brain activity were performed using a feedback-based visual-motor associative
learning functional MRI task. Order effect was examined using stratified
analysis.
RESULTS: Although both placebos improved motor function, benefit was greater when
patients were randomized first to expensive placebo, with a magnitude halfway
between that of cheap placebo and levodopa. Brain activation was greater upon
first-given cheap but not upon first-given expensive placebo or by levodopa.
Regardless of order of administration, only cheap placebo increased activation in
the left lateral sensorimotor cortex and other regions.
CONCLUSION: Expensive placebo significantly improved motor function and decreased
brain activation in a direction and magnitude comparable to, albeit less than,
levodopa. Perceptions of cost are capable of altering the placebo response in
clinical studies.
CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that
perception of cost is capable of influencing motor function and brain activation
in Parkinson disease.
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