Is Serum Ferritin an Additional Cardiovascular Risk Factor for All Postmenopausal Women?

Abstract

Background: Most of the studies on cardiovascular disease (CVD) risk factors in menopause have focused on serum lipid(lipoprotein) abnormalities and were conducted in populations which were not well controlled for several important influential factors. Methods: Two homogenous groups of 30 apparently healthy Caucasian premenopausal women and 3–5 years postmenopausal women who were nonobese, nonsmoking and not using estrogen were compared in a well-controlled cross-sectional design. Fasting serum ferritin and plasma total homocysteine (tHcy) were evaluated concomitantly to classical serum lipid(lipoprotein) risk factors. Relationships between risk factors and the influence of other contributing variables such as diet and body weight were also examined. Results: Serum total cholesterol (p < 0.01), low-density lipoproteins (LDL; p < 0.05) and triglycerides (p < 0.05) of postmenopausal women were greater than that of their menstruating counterparts, even though they ate a CVD-preventive diet, had similar body weight and body fat distribution. Their serum ferritin was almost 3-fold greater (p < 0.0001) but was still within normal limits, except for the 38.5% of postmenopausal women who exhibited values above the 80 µg/l limit that has been associated with sharp increases in the rate of heart disease in either gender. Serum ferritin was low in one third of the postmenopausal group (as low as in the premenopausal control group, whose dietary iron intake was slightly below the nutritional recommendation). The mean plasma tHcy of the postmenopausal group was almost twice as elevated (p < 0.0001). Both ferritin and tHcy were found to be linked to serum cholesterol. The correlation between tHcy and triglycerides was also significant. Conclusion: Early menopause is not associated with blood iron overload and CVD risk factor in an important proportion of women.

Serum ferritin levels are associated with carotid atherosclerosis in Chinese postmenopausal women: the Shanghai Changfeng Study

“…Ferritin can play a role in the formation of oxidised LDL ( 30 , 31 ) . When the LDL-cholesterol molecules become oxidised, they can be highly cardiotoxic; this is because they may cause direct endothelial injury or enhance the uptake of LDL by the macrophages, leading to the generation of foam cells ( 2 ) . Ferritin had been described in human atherosclerotic lesions and in diseased coronary arteries from patients with coronary artery disease ( 17 ) .…”

“…Postmenopausal women are at increased risk of CVD, which may be attributed to dyslipidemia, oxidative stress, loss of the protective effect of oestrogen, centralised adiposity, insulin resistance, and other factors ( 1 ) . The cessation of menses contributes to a general increase in body Fe, translating into elevated serum ferritin, as evidenced by a 3-fold greater ferritin in postmenopausal compared with premenopausal women ( 2 ) . Serum ferritin concentration is the best non-invasively measurable indicator of body Fe stores ( 3 ) .…”

Association of Oxidative Stress, Iron, and Centralized Fat Mass in Healthy Postmenopausal Women

“…Iron through free radicals causes oxidation of lipids and proteins, contributing to atherosclerosis or vasoconstriction by promoting oxidized low-density lipoprotein (oxLDL) and by promoting isoprostanes 2. The cessation of menses contributes to a general increase in body iron, translating into elevated serum ferritin,3 as evidenced by 3-fold greater ferritin in postmenopausal compared with premenopausal women 4. Although controversial,5–7 some epidemiological studies show a positive relationship between body iron stores and atherosclerotic CVD risk 8,9.…”

Urinary Catalytic Iron in Obesity

“…We have measured the active form of ferric iron because this is what plays a pathological role in DM and its complications, rather than simply reflecting body stores. Serum ferritin concentrations have been reported to be higher in postmenopausal women compared to premenopausal women, in part due to cessation of menses (37 ).…”