Carotid Atherosclerosis: MEtformin for Insulin ResistAnce Study (CAMERA)
Hypothesis: Treatment with metformin in overweight non-diabetic individuals with coronary heart disease and on standard cardiovascular risk reducing agents including statins will have a beneficial impact on carotid artery atherosclerosis compared to placebo.
Rationale: Once subjects have a heart attack, they remain at much higher than average risk of another heart attack and stroke, despite the best current therapies to lower their cholesterol and blood pressure and thin their blood. Many subjects with heart disease also have problems metabolising (i.e. processing) sugar even if they do not have diabetes. There is some evidence that metformin, a drug which improves sugar metabolism, decreases the risk of future heart attacks in diabetic patients. However, whether metformin further reduces the risk of heart disease beyond established treatments in people without diabetes is unknown.
Method: The investigators will test the ability metformin, a drug with proven safety, to slow the progression of furring up (known as atherosclerosis) of blood vessels in non-diabetic subjects with heart disease. This will be achieved by treating 2 groups of subjects with metformin and placebo pills respectively. To measure atherosclerosis, the investigators will carry out ultrasound scans of the big blood vessels in the neck at the start of the study, after 1 year and after 1.5 years of therapy.The investigators will then be able to assess whether metformin has had a beneficial impact.
|Study Design:||Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator)
Primary Purpose: Treatment
|Official Title:||A Randomised Placebo-controlled Trial of Metformin on Progression of Carotid Atherosclerosis in Non-diabetic Patients With Cardiovascular Disease Treated With Conventional Risk Reducing Agents|
- Difference in progression of carotid intima-media thickness (measured in millimetres) between groups treated with metformin and placebo [ Time Frame: 1.5 years ] [ Designated as safety issue: No ]
- Correlation of HbA1C, t-PA, CRP, IL-6, HOMA-IR and ICAM-1 with change in carotid IMT in metformin- and placebo-treated groups will be evaluated. [ Time Frame: 1.5 years ] [ Designated as safety issue: No ]
- Difference in progression of carotid total plaque area (measured in square millimetres) between groups treated with metformin and placebo [ Time Frame: 1.5 years ] [ Designated as safety issue: No ]
- Difference in progression of carotid total plaque volume (measured in cubic millimetres) between groups treated with metformin and placebo [ Time Frame: 1.5 years ] [ Designated as safety issue: No ]
|Study Start Date:||February 2009|
|Study Completion Date:||December 2012|
|Primary Completion Date:||December 2012 (Final data collection date for primary outcome measure)|
White film-coated tablets, 850mg tablet twice daily, 1.5 years duration
|Placebo Comparator: Placebo||
White coated tablet; one tablet twice daily; 1.5 years duration
Other Name: Dummy pill
|Glasgow Clinical Research Facility, NHS Greater Glasgow and Clyde|
|Glasgow, United Kingdom, G11 6NT|
|Principal Investigator:||Naveed Sattar, PhD||University of Glasgow|