Biomaterial Database

Does placebo lower blood-pressure? 1981

B A Gould, and S Mann, and A B Davies, and D G Altman, and E B Raftery

The effect of placebo on blood-pressure levels in 20 hypertensive patients was examined as part of a double-blind randomised controlled trial with indoramin. Blood-pressure was measured by both standard sphygmomanometry and ambulant intra-arterial monitoring. Blood-pressure reduction during the placebo phase, as measured by sphygmomanometry in the outpatient clinic, was highly significant for both systolic and diastolic pressures. In the same subjects, concomitant assessment by ambulatory monitoring showed no significant effect of placebo on intra-arterial pressure. After indoramin treatment blood-pressures measured in the clinic showed a mean reduction of 6/8 mm Hg whereas intra-arterial monitoring showed mean reductions of 18/13 mm Hg. The placebo response, therefore, appears to be an artifact of clinic blood-pressure measurement and its use as a control value in pharmacological trials may lead to serious underestimation of the efficacy of the active drug.

UI	MeSH Term	Description	Entries
D006973	Hypertension	Persistently high systemic arterial BLOOD PRESSURE. Based on multiple readings (BLOOD PRESSURE DETERMINATION), hypertension is currently defined as when SYSTOLIC PRESSURE is consistently greater than 140 mm Hg or when DIASTOLIC PRESSURE is consistently 90 mm Hg or more.	Blood Pressure, High,Blood Pressures, High,High Blood Pressure,High Blood Pressures
D007217	Indoramin	An alpha-1 adrenergic antagonist that is commonly used as an antihypertensive agent.	Wy-21901,Wy 21901,Wy21901
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D010919	Placebos	Any dummy medication or treatment. Although placebos originally were medicinal preparations having no specific pharmacological activity against a targeted condition, the concept has been extended to include treatments or procedures, especially those administered to control groups in clinical trials in order to provide baseline measurements for the experimental protocol.	Sham Treatment
D011897	Random Allocation	A process involving chance used in therapeutic trials or other research endeavor for allocating experimental subjects, human or animal, between treatment and control groups, or among treatment groups. It may also apply to experiments on inanimate objects.	Randomization,Allocation, Random
D001794	Blood Pressure	PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.	Systolic Pressure,Diastolic Pressure,Pulse Pressure,Pressure, Blood,Pressure, Diastolic,Pressure, Pulse,Pressure, Systolic,Pressures, Systolic
D001795	Blood Pressure Determination	Techniques used for measuring BLOOD PRESSURE.	Blood Pressure Determinations,Determination, Blood Pressure
D002940	Circadian Rhythm	The regular recurrence, in cycles of about 24 hours, of biological processes or activities, such as sensitivity to drugs or environmental and physiological stimuli.	Diurnal Rhythm,Nyctohemeral Rhythm,Twenty-Four Hour Rhythm,Nycthemeral Rhythm,Circadian Rhythms,Diurnal Rhythms,Nycthemeral Rhythms,Nyctohemeral Rhythms,Rhythm, Circadian,Rhythm, Diurnal,Rhythm, Nycthemeral,Rhythm, Nyctohemeral,Rhythm, Twenty-Four Hour,Rhythms, Circadian,Rhythms, Diurnal,Rhythms, Nycthemeral,Rhythms, Nyctohemeral,Rhythms, Twenty-Four Hour,Twenty Four Hour Rhythm,Twenty-Four Hour Rhythms
D002986	Clinical Trials as Topic	Works about pre-planned studies of the safety, efficacy, or optimum dosage schedule (if appropriate) of one or more diagnostic, therapeutic, or prophylactic drugs, devices, or techniques selected according to predetermined criteria of eligibility and observed for predefined evidence of favorable and unfavorable effects. This concept includes clinical trials conducted both in the U.S. and in other countries.	Clinical Trial as Topic