Association between iron overload and osteoporosis in patients with hereditary hemochromatosis.
CONCLUSIONS
In 87 patients with hereditary hemochromatosis, osteoporosis was detected in 25%, and osteopenia in 41%. Bone mineral density was independently associated with BMI, ALP levels, hypogonadism/menopause, and the amount of iron removed to reach depletion, but not with cirrhosis. Osteoporosis is influenced by iron overload in hemochromatosis.


BACKGROUND
To analyze prevalence, clinical characteristics and genetic background associated with osteoporosis in a retrospective study in Italian patients with hereditary hemochromatosis (HHC).


METHODS
In 87 consecutive patients with HHC, bone mineral density was systematically evaluated by dual energy x-ray absorptiometry of the lumbar spine (n = 87) and femoral neck (n = 66).


RESULTS
Osteoporosis was detected in 22 (25.3%), and osteopenia in 36 (41.4%) patients. Mean Z scores were -0.92 +/- 1.42 at lumbar spine and -0.35 +/- 1.41 at femoral neck. Lumbar spine T-score was independently associated with total ALP (p = 0.002), hypogonadism/menopause (p = 0.026), and iron overload (p = 0.033 for ferritin and p = 0.017 for iron removed). We observed a borderline significance for BMI (p = 0.069) and smoking status (p = 0.086). Lumbar spine osteoporosis was independently associated with lower BMI (OR 0.73, 95% CI 0.54-0.94), total ALP (OR 1.17, 95% CI 1-1.39 per 10 unit increase) and the amount of iron removed (OR 1.53, 95% CI 1-2.5 per 5 g increase). HFE genotypes did not differ between patients with and without osteoporosis.


CONCLUSIONS
Osteoporosis is observed in a quarter of unselected patients with HHC, independently of the genetic background, and is associated with ALP, hypogonadism, body weight, and severity of iron overload.
Valenti
L
L
Dipartimento di Medicina Interna, UO Medicina Interna IB, Padiglione Granelli, Universita degli Studi di Milano, Ospedale Policlinico Mangialli e Regina Elena Fondazione IRCCS, Milan, Italy.
Varenna
M
M
Fracanzani
A L
AL
Rossi
V
V
Fargion
S
S
Sinigaglia
L
L
D015502:Absorptiometry, Photon; D000328:Adult; D000469:Alkaline Phosphatase / Q000378:metabolism; D015992:Body Mass Index; D015519:Bone Density; D001851:Bone Diseases, Metabolic / Q000209:etiology / Q000235:genetics / Q000503:physiopathology; D005260:Female; D005272:Femur Neck / Q000503:physiopathology; D006432:Hemochromatosis / Q000150:complications* / Q000503:physiopathology; D006801:Humans; D008159:Lumbar Vertebrae / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000209:etiology* / Q000235:genetics / Q000503:physiopathology; D012189:Retrospective Studies
D000469:Alkaline Phosphatase