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Potential placebo effect in assessing idiopathic normal pressure hydrocephalus
Amitabh Gupta1, Anthony E Lang
1University of Toronto, Toronto Western Hospital, Morton and Gloria Schulman Movement Disorders Centre, Toronto, Ontario, Canada.
Journal of Neurosurgery
|January 22, 2011
Summary
Predicting idiopathic normal pressure hydrocephalus (INPH) treatment response is difficult. A patient improved with both actual and sham cerebrospinal fluid (CSF) removal, highlighting placebo effects in INPH diagnosis.
Area of Science:
- Neurology
- Neurosurgery
- Clinical Trials
Background:
- Idiopathic normal pressure hydrocephalus (INPH) management relies on shunt surgery.
- Predicting surgical outcomes in INPH is challenging.
- Cerebrospinal fluid (CSF) removal tests are used but have limitations.
Observation:
- A 76-year-old woman with suspected INPH showed improvement after both actual and sham large-volume lumbar punctures (LPs).
- This case demonstrates a significant placebo response in the context of INPH diagnostic procedures.
- The patient's condition improved irrespective of actual CSF removal.
Findings:
- Sham CSF removal procedures can elicit a clinical response in INPH patients.
- Placebo effects may confound the interpretation of traditional CSF removal tests.
- The predictive value of current diagnostic methods for INPH may be overestimated.
Implications:
- Clinical response to sham CSF removal could offer insights into predicting shunt surgery success.
- Rethinking diagnostic protocols for INPH is necessary to account for placebo responses.
- Further research into placebo effects in INPH is warranted for improved patient selection.
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