Associations between ABO blood groups and osteoporosis in postmenopausal women.

To investigate whether any significant differences exist in the prevalence of osteoporosis in relation to ABO blood groups, 227 postmenopausal women were evaluated for bone mineral density (BMD), body composition, and anthropometric variables. There were no significant differences in age, anthropometric parameters, or body composition between women with O blood type and those with non-O blood types. However, lumbar spine and proximal femur BMDs in subjects with blood type O averaged 0.87+/-0.13 g/cm2 and 0.76+/-0.12 g/cm2, respectively, which were significantly above the values in those with non-O blood types (0.72+/-0.11 g/cm2 and 0.61+/-0.09 g/cm2, p<0.05, respectively). Among the ABO blood groups, the women with blood type AB showed the lowest BMDs (0.71+/-0.10 g/cm2 and 0.59+/-0.09 g/cm2) in the lumbar spine and proximal femur. The prevalences of osteoporosis in the proximal femur and lumbar spine averaged 2.3- and 1.7-fold higher in women with blood type AB than in those with blood type O. Thus, ABO blood group status seems to have a significant relationship to the prevalence of osteoporosis in postmenopausal women.