Objectives: To investigate the effect of vitamin K2 treatment for a year on spinal bone mineral density (BMD) in postmenopausal women, comparing with vitamin D3 hormone replacement therapy and to determine the factors which affect the efficacy of vitamin K2 therapy.
Subjects and methods: Seventy-two postmenopausal women were randomized into four groups and treated with respective agents. Before the therapy, 6 and 12 months after the treatment, their lumbar spine BMD were measured by dual energy X-ray absorptiometry. The rates of change in BMD (delta BMD) were calculated. Correlations of BMD with age, year since menopause and the initial BMD were determined.
Results: Vitamin K2 suppressed the decrease in spinal BMD as compared with no treatment group. BMD in women treated with vitamin K2 was inversely correlated with their age (r = -0.54; P < 0.05).
Conclusions: Vitamin K2 therapy may be a useful method for preventing postmenopausal spinal bone mineral loss. In addition, the therapy should be started early in postmenopausal period.