Clinical Trial: The Prevalence of Thiamin Deficiency in Ambulatory Patients With Heart Failure
Study Status: Completed
Recruit Status: Completed
Study Type: Observational
Official Title: The Prevalence of Thiamin Deficiency in Ambulatory Patients With Heart Failure
Brief Summary: Patients with heart failure are at an increased risk for thiamin deficiency (TD), for many reasons such as malnutrition and the use of diuretic drugs. Thiamin is a B vitamin that plays an important role in the production of energy in body. Therefore, low levels of thiamin may limit the amount of energy available for the heart to pump blood. Recent thiamin supplementation trials have demonstrated significant improvements in heart function. However, while clinically important, the results of these studies are limited by their small sample sizes, indirect measurement of thiamin status and reliance on hospitalized patients. Therefore, the investigators' goal is to determine the prevalence of thiamin deficiency in ambulatory patients with heart failure by direct measurement of thiamin in red blood cells.
Detailed Summary:
Thiamin is a water-soluble B-complex vitamin which is supplied primarily from cereals and enriched grains in the ordinary diet. The majority of absorbed thiamin combines with ATP in the body to form thiamin pyrophosphate (TPP). TPP is a coenzyme which is involved in a number of energy production reactions in the body (metabolism of carbohydrates and some amino acids) . Therefore, theoretically, TD reduces the release of metabolic energy in the tissues . The adverse effects of TD include biventricular myocardial failure, tachycardia, peripheral edema, and retention of sodium which occurs as a result of heart failure . Therefore, our assumption is that TD in CHF patients may result in depletion of cellular energy and subsequently impair cardiac function. Previous studies done on CHF patients with TD found that thiamin supplementation was associated with improvement in heart contractility.
Patients with heart failure are at an increased risk for TD, for many reasons such as malnutrition, anorexia and the use of diuretic drugs, such as furosemide. Several studies have demonstrated a high prevalence of TD in hospitalized patients with heart failure, ranging from 13 % to 91% depending on the population studied. This wide variation is due to differences in the underlying nutrition status of subjects, the concurrent use of medications including loop diuretics, the severity of disease, and the measurement technique used for the assessment of thiamin status. These studies however, while clinically important, are limited by their small sample size and indirect measurement of thiamin status. Also, these studies have focused exclusively on the hospitalized patients, whereas ambulatory HF patients have received little attention.
Therefore, our primary objective to conduct a prospective, cross-sectional study to investigate the prevalenc
Sponsor: St. Michael's Hospital, Toronto
Current Primary Outcome: Prevalence of Thiamin deficiency as determined by Erythrocyte thiamin pyrophosphate (TPP) measured using a direct HPLC technique [ Time Frame: baseline ]
Original Primary Outcome: Same as current
Current Secondary Outcome:
- Eligible patients will be randomized to one of three commercially available doses of oral thiamin hydrochloride; 50 mg QD, 50 mg BID and 100 mg BID. They will take the supplements for 2 weeks. [ Time Frame: baseline to after two weeks of supplementation ]
- Plasma samples will be analyzed for the plasma levels of NE, BNP, F2-isoprostanes [ Time Frame: baseline and after supplementation ]
- Urinary excretion of thiamin following the 2 week supplementation period. [ Time Frame: by the end of two-week supplementation period ]
Original Secondary Outcome: Same as current
Information By: St. Michael's Hospital, Toronto
Dates:
Date Received: August 4, 2009
Date Started: May 2009
Date Completion:
Last Updated: December 21, 2012
Last Verified: December 2012
