Relationship between serum albumin and bone mineral density in postmenopausal women and in patients with hypoalbuminemia

Some discrepancies exist about the relationship between serum albumin level and the pathogenesis of osteoporosis; moreover, most of the studies available have especially concerned patients with osteoporosis, often associated with fractures. Our study, therefore, aims to investigate the presence of a relationship between serum albumin level and bone mineral density in a group of healthy women (n=650; mean age 59.0 +/- 7.4 years) who voluntarily underwent screening for osteoporosis only because they were menopausal (11.2 +/- 7.4 years since menopause) and, for comparison, in a group of outpatients (n = 44; mean age 57.6 +/- 7.0 years; 9.1 +/- 6.7 years since menopause) with hypoalbuminemia associated with diseases. The results show a lack of any relationship in healthy women between serum albumin value and bone mineral density; the lack of correlation was also shown when the postmenopausal women were down into normal, osteopenic and osteoporotic (WHO criteria) or in hypo, normal and hyperalbuminemic. The only significant parameters associated with lower bone mineral density, in fact, were age and years since menopause (p < 0.0001 and p < 0.0001 respectively at lumbar spine and p < 0.02 and p < 0.001 at femoral neck level). In the group of patients with hypoalbuminemia associated with diseases, on the other hand, a relationship between reduced bone mineral density and hypoalbuminemia was found (p < 0.01 and p < 0.05 respectively at lumbar spine and femoral neck). In conclusion, in healthy postmenopausal women the serum albumin level does not play a significant role in the pathogenesis of bone density reduction, which is mainly due to the number of years since menopause and advancing age. The hypoalbuminemia may be related to the reduction of bone mass only in the subjects affected by diseases associated with a significant albumin reduction.