Association of high serum ferritin concentration with metabolic syndrome

ABSTRACT

The metabolic syndrome affects 25% of western adults. It is closely linked to insulin resistance and implies an increased cardiovascular risk. Studies have shown an association between serum ferritin and one or more metabolic syndrome feature. The association between elevated iron stores and the metabolic syndrome, however, has been less well explored. We investigated the occurrence of iron overload in subjects selected for having metabolic syndrome, and investigated whether the association between elevated iron stores and the metabolic syndrome, if present will be related lo the sex or to the presence or absence of menstruation in females or not. The present study was done on 60 adult patients who have metabolic syndrome and divided into 3 groups; 20 premenopausal females, 20 postmenopausal females and 20 male patients. Age and sex matched 20 normal volunteers [7 premenopausal females, 7 postmenopausal females and 6 males] were taken as controls. Laboratory measurements included total cholesterol, HDL cholesterol, LDL cholesterol and triglycerides. Serum ferritin, C-reactive protein, fasting serum insulin and plasma glucose. Homeostasis model assessment of insulin resistance [HOMA-IR] was calculated as fasting insulin [micro U/ml] x fasting glucose [mg/dl]/ 405. Mean levels of serum ferritin were significantly higher in metabolic syndrome patients as one group compared to control subjects [168.3 +/- 23 Vs 85.6 +/- 17 micro g/l, p<0.001], the elevation was significant in premenopausal women [112.4 +/- 11 Vs 85.6 +/- 17 micro g/l, p<0.05] and was highly significant in postmenopausal women and in men [145.1 +/- 16 and 199.6 +/- 21 micro g/l respectively Vs 85.6 +/- 17 micro g/l, p<0.001]. Mean levels of serum ferritin were significantly higher in postmenopausal women compared with premenopausal women [145.1 +/- 16 Vs 112.4 +/- 11 micro g/l, p<0.05] and higher in men compared with postmenopausal women but were statistically not significant [199.6 +/- 21 Vs 145.1 +/- 16 micro g/l, p>0.05]. The occurrence of body iron excess in metabolic syndrome patients was 15% in premenopausal women, 30% in postmenopausal women, and 40% in men. Mean values of fasting serum insulin were significantly higher in metabolic syndrome patients as one group compared to control subjects [14.78 +/- 4.3 Vs 12.34 +/- 4.2 micro U/ml, p<0.001]. Mean values of estimated insulin resistance using the homeostasis model assessment [HOMA-IR] were significantly higher in metabolic syndrome patients as one group compared to control subjects [4.13 +/- 1.2 Vs 2.87 +/- 0.09, p<0.001]. Ferritin was positively correlated with W/H ratio, BMI, elevated triglycerides, elevated glucose levels, Insulin and HOMA-IR in metabolic syndrome patients. Elevated iron stores were found in metabolic syndrome patients and it was positively associated with BMI, elevated triglycerides, glucose and insulin resistance