A Phase 4 interventional study of Metformin and Matched Placebo (Capsules) in Congestive Heart Failure and Insulin Resistance, sponsored by University of Dundee. Completed at 1 site in United Kingdom. Open to participants aged 25 Years to 80 Years. Per ClinicalTrials.gov, last updated 2013-06-06.
Sponsored by University of Dundee · Phase 4, Interventional, and Treatment
Will metformin improve exercise capacity in chronic heart failure patients who has insulin resistance (pre-diabetic- means before they become diabetic)?
Exercise incapacity is one of the major debilitating symptoms of heart failure patients. Studies showed that heart failure patients will become insulin resistance (IR) or vice versa, severity of heart failure also correlates with the severity of insulin resistance. A recent study demonstrated that if we correct diabetic patient insulin resistance by giving them a drug to make them more sensitive to the effects of insulin, their exercise capacity improves. Therefore, we think that the same effects might happen in heart failure patients who have been identified to the insulin resistance by blood test. Insulin resistance means that they have not yet become diabetic and it is a stage the diabetic patients go through before they develop diabetes.
Therefore, we plan to use a drug called metformin (a diabetic drug), give it to heart failure patients who also have IR for 4 months and examine the effects before and after 4 months of treatment. It is a double blind control study, therefore, neither the examiner nor the patient know which drug they receive (either active drug- Metformin, or a placebo).
The main objective is to assess their exercise capacity using an exercise test called Innocor System. It is a bicycle based exercise test that involves patient breathing into a mouth piece before and during exercise in order for the machine to work out the maximum oxygen consumption and pumping power of the heart.
The other objectives of the trial are looking at the possible mechanisms of improving exercise capacity. We aim to answer the following questions by doing the following tests:
Does exercise capacity improve because of
5,701 studies on the registry are indexed under Heart Failure; 1,220 are open to participants now.
This study's enrollment of 62 is below the median of 72 across 3,736 interventional studies indexed under Heart Failure.
Browse Heart Failure studies →University of Dundee is the lead sponsor of 111 studies on the registry; 3 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Receiving Metformin for 4 months
Drug: Metformin
Matched Placebo for 4 months
Drug: Matched Placebo (Capsules)
Started at 500mg bd for 2 weeks. If well tolerated, increase to 1000mg bd for 14 weeks
Similar dosing regime as active comparator
Peak VO2
Peak VO2 after 4 months of intervention with either metformin or placebo. The Mean difference between baseline and after 4 months was analyzed using t-test comparing metformin and placebo.
Time frame: 4 months
Possible Mechanisms That Can Explain the Improvement of Exercise Capacity
VE/VCO2 Slope, measurement of the abnormal ventilatory response to exercise identified by an increased slope of ventilation (L/min) vs. CO2 production (VE/VCO2) (L/min) to incremental workload
Time frame: 4 months
Patients with symptomatic CHF were recruited from out patient cardiology clinics and local echocardiography database. Eligible patients were approached to have a fasting blood test to determine their fasting insulin resistance index (FIRI). CHF patients with a FIRI \>2.7 were considered to have IR and invited to participate in the study.
| Milestone | Metformin | Placebo |
|---|---|---|
| Started | 39 | 23 |
| Completed | 36 | 22 |
| Not completed | 3 | 1 |
| Withdrew: Lost to follow-up | 3 | 1 |
Peak VO2 after 4 months of intervention with either metformin or placebo. The Mean difference between baseline and after 4 months was analyzed using t-test comparing metformin and placebo.
| ml/kg/min | Metformin Arm | Placebo |
|---|---|---|
| Peak VO2 | -0.38 ± 1.4 | 3.6 ± 3.9 |
VE/VCO2 Slope, measurement of the abnormal ventilatory response to exercise identified by an increased slope of ventilation (L/min) vs. CO2 production (VE/VCO2) (L/min) to incremental workload
| Unitless | Metformin Arm | Placebo |
|---|---|---|
| Possible Mechanisms That Can Explain the Improvement of Exercise Capacity | -4.45 ± 10.72 | -0.23 ± 3.54 |
Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Metformin | — | 2/39 (5.1%) | 18/39 (46.2%) |
| Placebo | — | 1/23 (4.3%) | 3/23 (13%) |
| Event | Metformin | Placebo |
|---|---|---|
| Acute Coronary SyndromeCardiac disorders | 2/39 | 0/23 |
| Prostate CancerRenal and urinary disorders | 0/39 | 1/23 |
| Event | Metformin | Placebo |
|---|---|---|
| DiarrhoeaGastrointestinal disorders | 18/39 | 3/23 |
| Age, Categorical(Participants) | Metformin | Placebo | Total |
|---|---|---|---|
| <=18 years | 0 | 0 | 0 |
| Between 18 and 65 years | 23 | 9 | 32 |
| >=65 years | 16 | 14 | 30 |
| Age Continuous(years) | Metformin | Placebo | Total |
|---|---|---|---|
| Mean | 64 ± 8 | 68 ± 7 | 65 ± 8 |
| Sex: Female, Male(Participants) | Metformin | Placebo | Total |
|---|---|---|---|
| Female | 4 | 1 | 5 |
| Male | 35 | 22 | 57 |
| Region of Enrollment(participants) | Metformin | Placebo | Total |
|---|---|---|---|
| United Kingdom | 39 | 23 | 62 |
This study is completed, as verified in May 2013. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
University of Dundee