No link seen between body iron stores and cardiovascular risk

Markers of body iron stores, such as serum ferritin or serum transferrin receptor, are not associated with coronary heart disease (CHD) events, as reported in a recent study.

The study used data from a longitudinal prospective study of men living in the city of Gothenburg, Sweden, ‘The Study of Men Born in 1943’, and included 785 male participants (baseline age 50 years, mean body mass index [BMI] 26 kg/m²). All participants underwent medical examination and completed questionnaires to evaluate lifestyle factors. Researchers analysed biomarkers for iron stores (serum ferritin and serum transferrin receptor) from frozen blood samples.

Of the participants, 85 percent reported regular moderate physical activity for a minimum of 3 hours a week, 30 percent were smokers, and 16 percent had experienced several periods of stress or more in the last 5 years.

Compared with participants with S-ferritin <350, those with S-ferritin ≥350 ng/mL had significantly higher estimated glomerular filtration rate, BMI, systolic and diastolic blood pressure, and resting heart rate. They were also more likely to be hypertensive.

Over a follow-up of 21 years, 120 participants (15.2 percent) developed CHD, and 16 (2 percent) of them died. The all-cause mortality was 15.2 percent (n=120), including 40 cardiovascular deaths (5.1 percent).

In multivariable Cox regression analysis, CHD risk was independently predicted by daily smoking, hypertension, and increased resting heart rate. No association was found for body iron stores.

Additional studies are needed to establish the relationship between the intake of red meat and increased cardiovascular risk or to find more representative body iron store markers.