Additional identifiers
EudraCT number
ClinicalTrials.gov number
Protocol/serial number
3000
Study information
Scientific title
Double Blind Crossover Comparison of Diuretics in the Young
Acronym
Study hypothesis
This clinical trial aims to determine whether low-renin (ie salt sensitive) hypertension at a young age is caused by the kidneys hanging onto too much salt as a result of an over-active salt pump in the kidney. The kidneys have four salt pumps, and each is blocked by a different type of diuretic (salt losing) tablet. If one of the four is overactive we would expect patients to respond much better to one diuretic than to the alternative- rather than responding equally well to all types of diuretic. The study also aims to determine genetic mutations responsible for low-renin hypertension.
Ethics approval
MREC approved on the 7th July 2006 (ref: 06/MRE05/31)
Study design
Single centre randomised interventional treatment trial
Primary study design
Interventional
Secondary study design
Randomised controlled trial
Trial setting
Hospitals
Trial type
Treatment
Patient information sheet
Condition
Topic: Cardiovascular; Subtopic: Cardiovascular (all Subtopics); Disease: Cardiovascular
Intervention
Patients will receive, in a random order, 5 blocks of 5 week treatments consisting of:
1. Bendroflumethiazide 2.5 - 5 mg
2. Amiloride 20 - 40 mg
3. Spironolactone 50 - 100 mg
4. Frusemide 20 - 40 mg
5. A combination of bendroflumethiazide 1.25 - 2.5 mg and amiloride 10 - 20 mg
There will be a forced titration from lower to the higher dose half way through each dosing period. Each phase will start with two days of placebo treatment.
Intervention type
Drug
Phase
Not Applicable
Drug names
Bendroflumethiazide, amiloride, spironolactone, frusemide
Primary outcome measure
Difference in the fall in systolic blood pressure for each participant's best and second best drug
Secondary outcome measures
Not provided at time of registration
Overall trial start date
01/08/2006
Overall trial end date
01/01/2008
Reason abandoned (if study stopped)
Eligibility
Participant inclusion criteria
1. Aged 18 - 45 years
2. Male or female
3. Hypertensive:
3.1. Three clinic systolic blood pressure (SBP) greater than or equal to 140 mmHg; or
3.2. Three clinic diastolic blood pressure (DBP) greater than or equal to 90 mmHg; or
3.3. Ambulatory blood pressure monitoring (ABPM) or home blood pressure (BP) greater than or equal to 130 mmHg (SBP) or 85 mmHg (DBP)
4. 24-hour Na+ less than 160 mmol/l
5. Either:
5.1. Plasma renin less than or equal to 10 mU/L (measured untreated, or whilst receiving only CCB+/-diuretic) + plasma renin less than or equal to 40 mU/L (measured on an ACEi or ARB, which approximately doubles the plasma renin); or
5.2. Plasma renin less than 5 mU/L (measure untreated)
6. Receiving any antihypertensive drug other than a beta-blocker
Participant type
Patient
Age group
Adult
Gender
Both
Target number of participants
Planned sample size: 30
Participant exclusion criteria
1. Documented history of gout
2. Abnormal renal function (both elevated serum creatinine and reduced creatinine clearance)
3. SBP greater than 170 mmHg or DBP greater than 110 mmHg despite treatment with permitted background treatment
Recruitment start date
01/08/2006
Recruitment end date
01/01/2008
Locations
Countries of recruitment
United Kingdom
Trial participating centre
Clinical Pharmacology Unit
Cambridge
CB2 0QQ
United Kingdom
Sponsor information
Organisation
Cambridge University Hospitals NHS Foundation Trust (UK)
Sponsor details
Addenbrookes Hospital
Box 277
Hills Road
Cambridge
CB2 2QQ
United Kingdom
Sponsor type
Government
Website
Funders
Funder type
Charity
Funder name
British Heart Foundation (BHF) (UK)
Alternative name(s)
BHF
Funding Body Type
private sector organisation
Funding Body Subtype
foundation
Location
United Kingdom
Results and Publications
Publication and dissemination plan
Not provided at time of registration
Intention to publish date
Participant level data
Not provided at time of registration
Basic results (scientific)
Publication list