Make your own free website on Tripod.com
PharmInfoNet HomePage
CardioConsult Reviews

CardioConsult Reviews (CCR) is a periodic collection of summaries of the peer-reviewed cardiovascular literature. CCR is designed for cardiologists and other health professionals interested in the latest cardiovascular research news.


CardioConsult Discussion Group

Qualified health professionals may join the CARDIO-CONSULT E-mail Discussion Group and consult with their peers from around the world.

CardioConsult Reviews

Vol.1, #5: May, 1998

Published by: VirSci Corporation
1998 VirSci Corporation
Complete Index Other Reviews in This Issue Other Issues

Is Too Much Iron in the Blood Related to Heart Attack?


Paper: Association between body iron stores and the risk of acute myocardial infarction in men

Authors: Tuomainen, T-P, et al

Ref: Circulation. 1998;97:1461-1466.

Type: Case-control study


Summary: Iron, a transition metal with oxidating properties, has the ability to catalyze toxic redox reactions. Some studies have demonstrated a relationship between excessive iron and coronary heart disease (CHD), but the results have been inconsistent in human populations. This study takes advantage of a recently developed method of reliably assessing body iron stores -- the concentration ratio of serum transferrin receptor to serum ferritin (TfR/ferritin) -- to examine the impact of body iron stores on first acute myocardial infarction (AMI) in a group of men in Finland.

Subjects were participants in the Kuopio Ischemic Heart Disease Risk Factor Study, which prospectively examined a cohort of 1,931 men with no clinical CHD at baseline. The TfR/ferritin ratio was compared between 99 men who had an AMI during an average 6.4 years of follow-up, and 98 men without AMI who served as controls and were matched for age, examination year, and residence. Transferrin receptor assays were used to determine the TfR/ferritin ratio.

The mean TfR/ferritin ratio was significantly lower in cases (15.1) than in controls (21.3), indicating a link between high body iron stores and AMI. Other risk factors that differed between cases and controls included smoking, serum HDL-cholesterol, maximal oxygen uptake, plasma fibrinogen concentration, and serum copper concentration. In models adjusting for strong risk factors for AMI and indicators of inflammation and alcohol intake, men in the lowest and second lowest thirds of the TfR/ferritin ratio had a 2.9-fold and 2.0-fold risk of AMI, respectively, compared with men in the highest third. There was a synergism between body iron stores and LDL-cholesterol in increasing the risk of AMI. AMI risk also increased with dietary iron intake; for each 1 mg of iron daily, AMI risk increased 8.4%. The relationship between AMI and TfR/ferritin ratio was strongest in men who did not use antioxidative vitamins or aspirin.

The investigators noted that the risk of AMI due to body iron stores may be greater in Finnish men than in Americans, because the use of antioxidative vitamins and aspirin is rare in Finland and quite common in America. More research is needed on this relationship. The researchers concluded that men with high body iron stores have a twofold to threefold increased risk of first AMI. They added, "Randomized preventive trials concerning the effect of iron depletion [for example, through blood donation] on coronary events are necessary to ultimately verify or refute the iron-CHD hypothesis."

Last modified on Thursday, 07-Feb-2002 00:32:22 EST.


*

CCR Home Page

PharmInfoNet Homepage

PharmInfoNet HomePage