Previous studies had found that patients with cardiovascular diseases such as heart failure had worse outcomes when there was an iron deficiency. In patients with heart failure, treatments with intravenous iron improved patients’ symptoms, functional capacity, and quality of life.
Patients for this research were all enrolled in the FAIR-HF2 trial, which investigated the impact of intravenous iron supplementation on the risk of death in patients with heart failure.
Current Study
This current study looked at the association between iron deficiency and heart diseases in the general population. It included 12,164 participants from three European population-based cohorts.
The median age of participants was 59 years, and 55% were women. At the beginning of the study, lifestyle and medical issues were assessed through a thorough clinical assessment, including cholesterol, high blood pressure, diabetes, and smoking.
All participants were classified with either absolute iron deficiency, which includes store iron (ferritin), or functional iron deficiency, which includes iron in storage (ferritin) and iron in circulation for use by the body (transferrin).
The author of the study, Dr. Schrage, explained: “Absolute iron deficiency is the traditional way of assessing iron status, but it misses circulating iron. The functional definition is more accurate as it includes both measures and picks up those with sufficient stores but not enough in circulation for the body to work properly.”
Participants were followed up for coronary heart disease and stroke, death due to cardiovascular diseases, and all-cause death. After adjusting for lifestyle behaviors and illness, researchers analyzed the association between iron deficiency and health outcomes.
Researchers found that during a follow-up of 13.3 years, there were 2,212 deaths. Of these, a total of 573 participants died from a cardiovascular cause.
Functional iron deficiency was associated with a 24% higher risk of coronary heart disease, 26% raised risk of cardiovascular mortality, and 12% increased risk of all-cause mortality compared to those who did have functional iron deficiency.
Absolute iron deficiency was associated with a 20% raised risk of coronary heart disease compared to those who did not have the condition. It was also not linked with mortality. There were also no associations between iron status and incident stroke.
“This analysis suggests that if iron deficiency had been absent at baseline, about 5% of deaths, 12% of cardiovascular deaths, and 11% of new coronary heart disease diagnoses would not have occurred in the following decade,” said Dr. Schrage.
It was noted that future studies should examine the associations in younger and non-European cohorts. They should also focus on randomized trials investigating the effect of treating iron deficiency in the general population.