Comparison of effects of combined angiotensin converting enzyme inhibitor and low dose thiazide diuretic on insulin action in patients with hypertension and type two diabetes: a double-blind crossover study

ISRCTN	ISRCTN41655008
DOI	https://doi.org/10.1186/ISRCTN41655008
Secondary identifying numbers	203/01

Submission date: 19/12/2006
Registration date: 06/02/2007
Last edited: 03/05/2011

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Nutritional, Metabolic, Endocrine

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Plain English summary of protocol

Not provided at time of registration

Contact information

Prof Patrick Bell
Scientific

Regional Centre for Endocrinology
Level One
Royal Victoria Hospital
Belfast
BT12 6BA
United Kingdom

Email	patrick.bell@royalhospitals.n-i.nhs.uk

Study information

Study design	Randomised double-blind crossover study
Primary study design	Interventional
Secondary study design	Randomised controlled trial
Study setting(s)	Not specified
Study type	Treatment
Scientific title
Study objectives	New blood pressure targets have resulted in increased use of antihypertensive drugs including combinations. This study aimed to establish the safety in terms of insulin sensitivity of a low dose thiazide (bendroflumethiazide 1.25 mg)/Angiotensin Converting Enzyme (ACE) inhibitor combination.
Ethics approval(s)	Research Ethics Committee, Royal Victoria Hospital on behalf of Queens University Belfast on 22/082001(ref: 203/01)
Health condition(s) or problem(s) studied	Type two diabetes and essential hypertension
Intervention	Patients were commenced on captopril 50 mg twice daily and this continued throughout the trial. Patients were randomly assigned to either bendroflumethiazide 1.25 mg once daily or placebo for twelve weeks before being crossed over to receive the alternate randomly allocated bendroflumethiazide or placebo. Insulin action was assessed at the end of the placebo run-in and at the end of the two treatment periods using an isoglycaemic hyperinsulinameic clamp technique.
Intervention type	Drug
Pharmaceutical study type(s)
Phase	Not Specified
Drug / device / biological / vaccine name(s)	Captopril and bendroflumethiazide
Primary outcome measure	When compared to captopril alone, treatment with low dose bendroflumethiaizide (1.25 mg) in combination with captopril produced a 23% reduction in glucose infusion rates required to maintain isoglycaemia and there was a comparable reduction in isotopically induced decline in peripheral insulin sensitivity most probably in skeletal muscle. The combination of low-dose bendroflumethiazide 1.25 mg and captopril resulted in a significant reduction in blood pressure (6/3 mmHg) compared to captopril alone.
Secondary outcome measures	Serum potassium was significantly lower after treatment with captopril and bendroflumethiaizide as compared to treatment with captopril alone.
Overall study start date	01/08/2001
Completion date	01/04/2004

Eligibility

Participant type(s)	Patient
Age group	Adult
Sex	Not Specified
Target number of participants	15
Key inclusion criteria	1. Aged 40 to 65 years 2. Hypertension (either newly diagnosed or controlled on treatment) 3. Type two diabetes established on dietary treatment with or without oral hypoglycaemic agents 4. Fasting plasma glucose in the range 7 - 12 mmol/l
Key exclusion criteria	1. Secondary hypertension 2. Hepatic or renal disease or were taking Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) or steroids which may affect insulin action
Date of first enrolment	01/08/2001
Date of final enrolment	01/04/2004

Locations

Countries of recruitment

Northern Ireland
United Kingdom

Study participating centre

Regional Centre for Endocrinology

Belfast
BT12 6BA
United Kingdom

Sponsor information

Royal Victoria Hospital (UK)
Hospital/treatment centre

c/o Professor Patrick Bell
Regional Centre for Endocrinology
Level One
Belfast
BT12 6BA
Northern Ireland
United Kingdom

Email	patrick.bell@royalhospitals.n-i.nhs.uk
Website	http://www.royalhospitals.org/
"ROR"	https://ror.org/03rq50d77

Funders

Funder type

Research organisation

Metabolic Research fund - Royal Victoria Hospital, Belfast, N.Ireland (UK)

No information available

Royal Fellowship - Royal Victoria Hospital (UK)

No information available

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to share	No
IPD sharing plan summary	Not provided at time of registration
Publication and dissemination plan	Not provided at time of registration
IPD sharing plan

Study outputs

Output type	Details	Date created	Date added	Peer reviewed?	Patient-facing?
Results article	results	01/05/2008		Yes	No