Effects of Losartan on Insulin Resistance in Patients With Heart Failure

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the effects of losartan, an ARB, on glucose metabolism and inflammatory cytokines in CHF patients treated with ACE inhibitors.

Detailed Description
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Chronic heart failure (CHF) is associated with marked insulin resistance, characterized by both fasting and stimulated hyperinsulinemia. Furthermore, insulin resistance is a predictor of CHF and associated with more severe disease and a worse prognosis in patients with CHF. In CHF patients, therefore, insulin resistance is not merely a function of adiposity and may have implications in the pathophysiology of CHF disease progression. Angiotensin II negatively modulates insulin-mediated actions by regulating multiple levels of the insulin signaling cascade such as the insulin receptor, IRS, and PI3-kinase. Furthermore, both ACE inhibitors and angiotensin II receptor blockers (ARB) improve glycemic status not only in patients with type II diabetes but also in patients with hypertension and the metabolic syndrome. On the other hand, it is well known that some cytokines, such as TNF-α, are involved with pathophysiology of insulin resistance and CHF. However, it is still unclear whether the ARB improves insulin resistance in CHF patients already treated with ACE inhibitors and whether there is the relationship between insulin resistance and inflammatory cytokines in CHF patients already treated with ACE inhibitors. Therefore, the purpose of this study is to evaluate the effects of losartan, an ARB, on glucose metabolism and inflammatory cytokines in CHF patients treated with ACE inhibitors.

Official Title
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Losartan Improved Insulin Resistance and Decreased Inflammatory Cytokines in Patients With Chronic Heart Failure Treated With Angiotensin Converting Enzyme Inhibitors

Conditions
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Heart Failure

Intervention / Treatment
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* Drug: losartan


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: chronic stable heart failure Exclusion Criteria: renal dysfunction or under treatment with antidiabetic agents
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double


Arms and Interventions

| Intervention/Treatment |
| --- |
|Drug: losartan|losartan 50-100mg for 16 weeks|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| insulin resistance |  | 16 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| inflammatory cytokines |  | 16 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Heart Failure, Insulin Resistance, Losartan, ACE inhibitor, Inflammatory cytokine