Endocrine Abstracts

Zoledronic acid (ZA) treatment increases bone mineral density (BMD), decreases bone turnover markers and reduces the risk of fractures in patients with osteoporosis (1).

Objective: Observe and quantify the changes in BMD and bone turnover markers in postmenopausal osteoporosis (PO) patients treated annually with zoledronic acid 5 mg intravenously.

Material and Methods: Medical records (MR) of PO patients whom received ZA from 2007 to 2017 were retrospective evaluated. Parametric test (paired T-test for quantitative variable) × 2 for qualitative variable were performed following variable distribution. Kaplan Meier- log rank test, lineal and cox regression were performed. SPSS and Stata14.0 software were used for statistical analysis.

Results: 130 women were included

A percentage of 50.8% had received prior treatment with oral bisphosphonates for a time period of 1.7 ± 2.4 years, 15 patients received others previous treatments.

The major prescription for ZA was: lack of response to oral bisphosphonates 36.2% (n = 47/130), very low bone mass density (T-sc < –3.5): 31.5% (n = 41/130), new fracture under treatment with oral bisphosphonates: 7.7% (n = 10/130), digestive intolerance to oral bisphosphonates 24.6% (n = 32/130) and previous history of fx: 45.4% (n = 59/130).

From total 84 patients received 2 infusions and 45 patients, 3 infusions with ZA respectively.

Adverse events were observed in 4.6% (n = 8) of patients.

One year after ZA, there was a significant increase at lumbar spine(LS) BMD in 3.7% (n = 0.009) and total hip (TH) 4.5% (P = 0.004), however in the following years the increase was not significant in both regions. There were no significant changes in femoral neck (FN).

There was a significant decrease 49% (P < 0.001) in C–telopeptide of type I collagen (CTX) values, but only after the first year of infusion.

Conclusions: In our cohort the annual treatment with intravenous ZA 5 mg produced a significant increase in BMD for LS and TH and a significant decrease in CTX per year. Adverse effects were uncommon. We believe that this study despite its limitations, provides useful information regarding the effectiveness and safeness of ZA as a therapeutic option for PO treatment.