Details

Autor(en) / Beteiligte

• Hall, Kathryn T
• Lembo, Anthony J
• Kirsch, Irving
• Ziogas, Dimitrios C
• Douaiher, Jeffrey
• Jensen, Karin B
• Conboy, Lisa A
• Kelley, John M
• Kokkotou, Efi
• Kaptchuk, Ted J
• Lo, Anthony WI

Titel

Catechol-O-methyltransferase val158met polymorphism predicts placebo effect in irritable bowel syndrome

Ist Teil von

• PloS one, 2012-10, Vol.7 (10), p.e48135

Ort / Verlag

United States: Public Library of Science

Erscheinungsjahr

2012

Quelle

Elektronische Zeitschriftenbibliothek - Frei zugängliche E-Journals

Beschreibungen/Notizen

• Identifying patients who are potential placebo responders has major implications for clinical practice and trial design. Catechol-O-methyltransferase (COMT), an important enzyme in dopamine catabolism plays a key role in processes associated with the placebo effect such as reward, pain, memory and learning. We hypothesized that the COMT functional val158met polymorphism, was a predictor of placebo effects and tested our hypothesis in a subset of 104 patients from a previously reported randomized controlled trial in irritable bowel syndrome (IBS). The three treatment arms from this study were: no-treatment ("waitlist"), placebo treatment alone ("limited") and, placebo treatment "augmented" with a supportive patient-health care provider interaction. The primary outcome measure was change from baseline in IBS-Symptom Severity Scale (IBS-SSS) after three weeks of treatment. In a regression model, the number of methionine alleles in COMT val158met was linearly related to placebo response as measured by changes in IBS-SSS (p = .035). The strongest placebo response occurred in met/met homozygotes treated in the augmented placebo arm. A smaller met/met associated effect was observed with limited placebo treatment and there was no effect in the waitlist control. These data support our hypothesis that the COMT val158met polymorphism is a potential biomarker of placebo response.