Low iron-binding capacity as a risk factor for myocardial infarction

Area of Science:

• Cardiovascular Medicine
• Hematology
• Iron Metabolism

Background:

• Previous Finnish research suggested ferritin as an independent risk factor for acute myocardial infarction.
• High iron stores may be atherogenic and contribute to sex differences in ischemic heart disease incidence.

Purpose of the Study:

• To investigate the role of iron metabolism parameters, including ferritin and total iron-binding capacity (TIBC), as risk factors for myocardial infarction.
• To examine sex differences in the association between iron parameters and myocardial infarction risk.

Main Methods:

• A randomly selected cohort of 2036 men and women aged 25-74 years was followed for 8.5 years.
• Classic coronary artery disease risk factors, iron, TIBC, and ferritin were measured.
• Cox proportional hazards models were used to assess independent risk factors for myocardial infarction.

Main Results:

• Total iron-binding capacity (TIBC) was a strong independent negative risk factor for myocardial infarction in men (RR = 0.95).
• Each 1 mumol/L increase in TIBC was associated with a 5.1% decrease in myocardial infarction risk.
• Ferritin and other iron parameters showed no significant predictive power for myocardial infarction in either sex.

Conclusions:

• Transferrin, indicated by TIBC, is an independent negative risk factor for myocardial infarction.
• Ferritin and other iron metabolism markers do not appear to contribute to myocardial infarction risk.
• Sex remains a significant risk factor for myocardial infarction independent of classic risk factors and iron metabolism parameters.