HFE p.C282Y homozygosity predisposes to rapid serum ferritin rise after menopause: A genotype-stratified cohort study of hemochromatosis in Australian women.

BACKGROUND AND AIM: Women who are homozygous for the p.C282Y mutation in the HFE gene are at much lower risk of iron overload-related disease than p.C282Y homozygous men, presumably because of the iron-depleting effects of menstruation and pregnancy. We used data from a population cohort study to model the impact of menstruation cessation at menopause on serum ferritin (SF) levels in female p.C282Y homozygotes, with p.C282Y/p.H63D simple or compound heterozygotes and those with neither p.C282Y nor p.H63D mutations (HFE wild types) as comparison groups. METHODS: A sample of the Melbourne Collaborative Cohort Study was selected for the "HealthIron" study (n = 1438) including all HFE p.C282Y homozygotes plus a random sample stratified by HFE-genotype (p.C282Y and p.H63D). The relationship between the natural logarithm of SF and time since menopause was examined using linear mixed models incorporating spline smoothing. RESULTS: For p.C282Y homozygotes, SF increased by a factor of 3.6 (95% CI (1.8, 7.0), P < 0.001) during the first 10 years postmenopause, after which SF continued to increase but at less than half the previous rate. In contrast, SF profiles for other HFE genotype groups increase more gradually and did not show a distinction between premenopausal and postmenopausal SF levels. Only p.C282Y homozygotes had predicted SF exceeding 200 µg/L postmenopause, but the projected SF did not increase the risk of iron overload-related disease. CONCLUSIONS: These data provide the first documented evidence that physiological blood loss is a major factor in determining the marked gender difference in expression of p.C282Y homozygosity.

Iron overload and cirrhosis in referred HFE p.C282Y homozygotes with normal transferrin saturation and elevated serum ferritin.

Background: levated transferrin saturation (TS) is an imperfect test to identify adults with high-iron gene (HFE) p.C282Y homozygosity or elevated hepatic iron concentration. Methods: e analyzed observations of non-screening, previously untreated p.C282Y homozygotes who presented with both normal TS (<50% men, <45% women) and elevated serum ferritin (SF; men, >300 µg/L; women, >200 µg/L). Iron overload was defined as hepatocyte iron grade 3 or 4, liver iron >35 µmol/g dry weight, or iron removed by phlebotomy ≥3 g. Cirrhosis was defined as regenerating nodules of hepatocytes surrounded by bands of fibrous connective tissue. Results: mong 917 referred p.C282Y homozygotes, 58 (33 men, 25 women) had normal TS and elevated SF (6.3% [95% CI 4.9% to 8.1%]). Of 58 patients, 14 (24.1%) underwent liver biopsy; all 14 had hepatocyte iron grade 3 or 4. Fatty infiltration was reported in 6 of 14 liver biopsies (42.9%). Liver iron was >35 µmol/g dry weight in 7 of 8 patients tested (87.5%). Iron removed by phlebotomy was ≥3 g in 75.0% (15/20) of men and 62.5% (5/8) of women. Of 58 patients, 3 (5.2%) had iron overload and cirrhosis; each also had a proven or possible non-iron liver condition that may have acted in synergy with liver iron to increase cirrhosis risk. Conclusions: Iron overload is common in non-screening, previously untreated HFE p.C282Y homozygotes with normal TS and elevated SF. Among our sample, 5.2% had cirrhosis. Clinicians should not assume that patients with normal TS and elevated SF do not have HFE p.C282Y homozygosity, iron overload, or cirrhosis.