The placebo effect in the pharmacologic treatment of patients with lower urinary tract symptoms.
OBJECTIVE
We reviewed placebo responses in randomised controlled trials (RCTs) for pharmacologic treatment of lower urinary tract symptoms (LUTS), including urinary incontinence (UI), overactive bladder, and benign prostatic hyperplasia. Review papers on placebo effects in non-urologic disorders were assessed to compare the magnitude of placebo responses in drugs for LUTS with those reported for other diseases.


METHODS
Data were retrieved from registration trials for LUTS drugs on the Web sites of the Food and Drugs Administration and the European Medicines Agency. Reviews were retrieved from Medline using the MeSH term "placebo effect" (English language; published between 1990 and 2005).


RESULTS
Placebo treatment of LUTS yields reductions in incontinence episodes (IEs) ranging from 32% to 65%, whereas prostate or UI symptom scores are reduced by 9-34%. Genuine drugs decrease IEs by 45-77% and symptom scores by 22-45%. Placebo responses are much lower when objective changes in voided volume or peak flow rate are assessed.


CONCLUSIONS
The placebo effect in LUTS has a strong behavioural component as patients become aware of their voiding habits and potential risk factors. Symptom severity, treatment naivety, study duration, and interaction with health care providers may also influence it. Proper patient selection, study duration, and objective and subjective outcome measures may better separate genuine treatment effects from artefacts. Observational studies with patients representative for real-life situations and covering a sufficient period of time could allow for better understanding of RCT results and their applicability in clinical practice.
van Leeuwen
Jules H Schagen
JH
Antonius Hospital, 3435 CM Nieuwegein, The Netherlands. j.schagen@Antonius.net
Castro
Ramiro
R
Busse
Michael
M
Bemelmans
Bart L H
BL
D018674:Adrenergic Antagonists / Q000627:therapeutic use; D002986:Clinical Trials as Topic; D004791:Enzyme Inhibitors / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008297:Male; D018727:Muscarinic Antagonists / Q000627:therapeutic use; D015990:Placebo Effect; D011470:Prostatic Hyperplasia / Q000188:drug therapy; D017367:Selective Serotonin Reuptake Inhibitors / Q000627:therapeutic use; D001748:Urinary Bladder Neck Obstruction / Q000188:drug therapy; D053201:Urinary Bladder, Overactive / Q000188:drug therapy; D014549:Urinary Incontinence / Q000188:drug therapy; D014570:Urologic Diseases / Q000188:drug therapy*
D018674:Adrenergic Antagonists; D004791:Enzyme Inhibitors; D018727:Muscarinic Antagonists; D017367:Selective Serotonin Reuptake Inhibitors