Serum ferritin is a risk factor for stroke in postmenopausal women.
OBJECTIVE
Iron is an essential element for the human body. It has, however, been suggested that excessive iron stores may increase the risk of vascular disease. So far, epidemiologic studies on stroke are sparse.


METHODS
We studied the association between iron status and stroke risk in a population-based cohort of 11 471 Dutch postmenopausal women between 49 and 70 years of age. Women were included between 1993 and 1997 and followed up until January 1, 2000, for cerebrovascular events. We conducted a case-cohort study by using all stroke cases (n=63) and a random sample of the baseline cohort (n=1134). Serum ferritin, serum iron, and transferrin saturation were measured as markers of iron status. A weighted Cox proportional-hazards model was used to estimate crude and multivariate-adjusted hazard ratios for tertiles of different iron parameters in relation to stroke.


RESULTS
In a multivariate model, the highest tertile of serum ferritin concentration was associated with an increased risk of stroke (hazard ratio [HR], 1.45; 95% confidence interval [CI], 0.87 to 2.42) compared with the lowest tertile. For ischemic stroke, the increase was more pronounced (HR, 2.23; 95% CI, 1.05 to 4.73) and reached statistical significance.


CONCLUSIONS
Neither serum iron nor transferrin saturation was associated with an increased stroke risk. However, higher serum ferritin concentrations in postmenopausal women are associated with an increased risk of ischemic stroke.
Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, HP Str 6.131, PO Box 85500, 3508 GA Utrecht, The Netherlands.
Daphne L
DL
van der A
Diederick E
DE
Grobbee
Mark
M
Roest
Joannes J M
JJ
Marx
Hieronymus A
HA
Voorbij
Yvonne T
YT
van der Schouw
D000368:Aged; D015992:Body Mass Index; D002545:Brain Ischemia / Q000473:pathology; D015331:Cohort Studies; D005260:Female; D005293:Ferritins / Q000097:blood*; D006801:Humans; D006973:Hypertension / Q000175:diagnosis; D007501:Iron / Q000097:blood / Q000378:metabolism; D008875:Middle Aged; D015999:Multivariate Analysis; D018384:Oxidative Stress; D017698:Postmenopause; D016016:Proportional Hazards Models; D012306:Risk; D012307:Risk Factors; D012907:Smoking; D020521:Stroke / Q000175:diagnosis* / Q000473:pathology; D014168:Transferrin / Q000096:biosynthesis
D014168:Transferrin; D005293:Ferritins; D007501:Iron