Iron stores in 1359, 30- to 60-year-old Danish women: evaluation by serum ferritin and hemoglobin.

Iron status, including serum (S-)ferritin and hemoglobin (Hb), was assessed in a population survey comprising 1359 nonpregnant Danish women in age cohorts of 30, 40, 50, and 60 years. S-ferritin levels were similar in 30- and 40-year-old women; they displayed a significant increase in 50-year-old women and a further significant increase in 60-year-old women. In the 30- and 40-year-old women, median S-ferritin was 38 micrograms/l, 5-95 percentile 6-135 micrograms/l; 17.2% had values less than 15 micrograms/l (i.e., depleted iron stores), 22.7% values from 15 to 30 micrograms/l (i.e., small iron stores), and 60.1% values greater than 30 micrograms/l (i.e., replete iron stores). In the 50-year-old women, median S-ferritin was 54 micrograms/l, 5-95 percentile 10-164 micrograms/l; 10.3% had values less than 15 micrograms/l, 16.5% values from 15 to 30 micrograms/l, and 73.2% values greater than 30 micrograms/l. For the 60-year-old women, median S-ferritin was 84 micrograms/l, 5-95 percentile 25-249 micrograms/l; 1.6% had values less than 15 micrograms/l, 8.6% values from 15 to 30 micrograms/l, and 89.8% values greater than 30 micrograms/l. Blood donors (n = 180) had lower S-ferritin than nondonors in all age-groups (p less than 0.001). In the entire series, Hb levels were similar in 30- and 40-year-old women, median 137 milligrams (8.5 mmol/l), 5-95 percentile 121-152 milligrams (7.5-9.4 mmol/l), and higher in 50- and 60-year-old women, median 140 milligrams (8.7 mmol/l), 5-95 percentile 123-158 milligrams (7.6-9.8 mmol/l) (p less than 0.0001). Hb values less than 121 milligrams (7.5 mmol/l) were observed in 3.8% of the women. Women with S-ferritin less than 15 micrograms/l (n = 161) had lower Hb, median 134 milligrams (8.3 mmol/l), than those with S-ferritin greater than or equal to 15 micrograms/l, median 139 milligrams (8.6 mmol/l) (p less than 0.001). Iron deficiency anemia (S-ferritin less than 15 micrograms/l and Hb less than 121 milligrams) was seen in 2.3% of 30- and 40-year-old women, and in 1.1% of 50- and 60-year-old women.