Effect of a single dose of zoledronic acid on bone mineral density and trabecular bone score in Indian postmenopausal osteoporotic women with and without type 2 diabetes mellitus - A prospective cohort pilot study.

PURPOSE: The objectives were to study the effect of a single dose of intravenous (IV) zoledronic acid (ZA) on changes in bone mineral density (BMD) (lumbar spine (LS), hip, & distal forearm), trabecular bone score (TBS) and bone turnover markers (BTMs) in postmenopausal osteoporotic women with and without diabetes over 12 months. METHODS: Patients were divided into two groups: type 2 diabetes mellitus (T2DM) (n = 40) and non-DM (n = 40). Both groups received a single dose of 4 mg IV ZA at baseline. The BMD with TBS and BTMs (ß-CTX, sclerostin, P1NP) were measured at baseline, six months, and 12 months. RESULTS: At baseline, BMD in all three sites was similar in both groups. T2DM patients were older and had lower BTMs than non-DM patients. The mean increase in LS-BMD (gram/cm2) at 12 months in T2DM and the non-DM group was 3.6 ± 4.7% and 6.2 ± 4.7 %, respectively (P = 0.01). However, the age adjusted mean difference in LS BMD increment between two groups at one year was - 2.86 % (-5.02% to -0.69%), P = 0.01. There was a comparable change in BMD at other two sites, BTMs, and TBS in both the groups over one year follow-up. CONCLUSION: The gain in the LS-BMD was significantly lower in T2DM group compared to non-DM subjects over 12 months after a single IV infusion of 4 mg ZA. The explanation for this could be low bone turnover in diabetes subjects at baseline.