An experimental study was conducted to track changes occurring in the bone turnover number and bone mineral density (BMD) on administration with different medications related to osteoporosis. A daily teriparatide (20 µg/day) administration was given to the patient for a period of 24 months and the changes in BMD, the turnover rate and the balance [multiple of median formation/multiple of median resorption (MoMf/MoMr)] which were readily affected by the selection of different bone resorption inhibitors were studied. The turnover rate was estimated by mathematical formula √ (MoMf2 + MoMr2), where MoMf refers to the bone-specific alkaline phosphatase (BAP) value/18.6 and MoMr refers to tartrate-resistant acid phosphatase 5b (TRACP-5b) value/463.

A total of 121 osteoporotic women (mean age 82.4years) were randomly enrolled and administered with minodronate (50 mg/28 days), raloxifene (60 mg/day) or eldecalcitol (0.75 µg/day) after discontinuation of teriparatide. The BMD was measured at a time interval of 0, 24 and 48 weeks; BAP values and TRACP-5b were measured at a time interval of 0, 12, 24, 36 and 48 weeks after administration of bone resorption inhibitors. The study unveiled the significant BMD increase in the minodronate group from week 0 to weeks 24 and 48, and the turnover rate was significantly reduced at week 12 and remained same over the entire course in all three groups. It was noticed that the speed of change of turnover rate was higher in the minodronate group. At week 12, the balance in the minodronate group shifted significantly towards formation dominance (to 0.97 from 0.87) and then again towards resorption dominance (to 0.84) at week 24. Until week 48, no further advancement in resorption dominance was observed. The balance in the raloxifene and eldecalcitol groups shifted towards the resorption dominance gradually over the entire course of time.

At the end of the study, it was found that the BMD effect increased more with the minodronate administration and it was dependent both on the decreased turnover rate and also on changes in the balance after the teriparatide discontinuation.