Symptom relief and the placebo effect in the trial of an anti-peptic drug.

Abstract

SUMMARY In order to determine some of the factors involved in the response of duodenal ulcers to placebo treatment, the following factors were studied prospectively during a double-blind, placebocontrolled trial: demographic data; duration of illness and effect of treatment; expectation of success or failure of the new drug; presence of psychiatric problems; and suggestibility. Healing (measured by endoscopy) occurred in 37 patients, 17 of whom were receiving placebo; relief of symptoms occurred in 35 patients, 16 of whom were receiving placebo. There was no significant difference between drug and placebo. Healing was significantly associated with relief of symptoms but with no other variable. Relief of symptoms was more common in male patients and in those from higher social classes, as well as in patients who expected a complete cure and those without evidence of psychiatric problems. The natural history of the disease may be different in these patients. Unexpectedly, suggestibility was not associated with healing or relief of symptoms in the patients receiving placebo.The 'placebo effect' (the increased healing of, for example, duodenal ulcers during treatment with placebo) is a well-recognised but little understood phenomenon which makes the interpretation of therapeutic trials extremely difficult. For any patient with any illness, response to treatment = natural healing+placebo effect+effects of drug (or other treatment). For example, during recent randomised double-blind studies of cimetidine in healing duodenal ulcers, the proportion of patients whose ulcers healed or whose symptoms were relieved during treatment with placebo tablets ranged from less than 20% to over 80%.1 The determinants of the placebo effect have been difficult to identify, as neither personality type nor therapeutic situation are specific for such effects. As expectations about the results of treatment influence the response to therapy,2 it has been found necessary to undertake therapeutic trials on the basis of 'double-blind' ignorance of the type of treatment (whether active or placebo) on the part of both investigator and

Efficacy of Lactobacillus casei Shirota for patients with irritable bowel syndrome

“…Furthermore, it is not known whether women are more receptive than men to a positive patient-physician relationship. Literature data on the influence of sex on placebo response are inconsistent [44,[49][50][51][52].…”

Meta‐analysis: incidence of endoscopic gastric and duodenal ulcers in placebo arms of randomized placebo‐controlled NSAID trials

“…Adverse events were reported in between 19% 6 and 60% 55 of healthy volunteers and this number was more frequent after repeated dosing 6 and the proportion of healthy volunteers with adverse events could change with time 55 . The duodenal ulcer‐healing rate is up to 45% while taking placebo 56 . The placebo effect contributes to the observed treatment effect and differs according to clinical conditions and interventions 57 .…”

Challenges and recommendations for blinding in behavioral interventions illustrated using a case study of a behavioral intervention to lower blood pressure

“…Furthermore, both counselors and patients may be familiar with typical treatments for the condition, and may have specific expectations for the active intervention and placebo. This has been demonstrated both in pharmacological and non-pharmacological studies, for both clinicians and patients [21][22][23][24].…”