The effect of ipriflavone on osteopenia in ovariectomized women

This study evaluated the preventative effect of ipriflavone on osteopenia in 21 female patients who had either reached natural menopause or had been bilaterally ovariectomized at least 3 years before the beginning of the study. Out of the 21 patients, 18 had been ovariectomized, 11 of whom were monitored continuously for more than 48 weeks. These 11 patients were divided into groups A and B. The remaining three patients who reached natural menopause were administered the drug for less than 48 weeks, and were excluded from the study. Ipriflavone 600 mg/day was administered to group A (n=4), and ipriflavone 600 mg plus ‘Premarin’ 0.625 mg/day to group B (n=7), each day for 48 weeks. The bone mineral density (BMD) of L2–L4 of the subjects who were monitored continuously for 48 weeks was measured using dual-energy x-ray absorptiometry (DXA) (Norland XR-26). The BMD of those subjects who received ipriflavone alone decreased only slightly for the first 36 weeks, a smaller decrease than those who did not, and at 48 weeks a slight improvement appeared. Those subjects receiving ipriflavone plus ‘Premarin’ showed an increase in BMD at 24 weeks but at 48 weeks the BMD had returned to the pretreatment level. Next we divided groups A and B into 2 sub-groups (A₁, A₂; B₁, B₂) according to their BMD levels following the 48-week treatment. In all groups, there was a tendency for serum osteocalcin, urinary hydroxyproline/creatinine ratio, and urinary calcium/creatinine ratio to decrease; the decrease in the hydroxyproline/creatinine ratio was especially evident in groups A₁ and B₁. Thus, our study suggested ipriflavone, administered alone, had a potentially preventative effect on rapid bone loss in females who had recently been ovariectomized.