Effect of Tibolone on Bone Mineral Density in Postmenopausal Women: Systematic Review and Meta-Analysis

SIMPLE SUMMARY: Low bone mineral density (osteoporosis) is associated with vertebral and nonvertebral fractures in postmenopausal women. Tibolone is a low-risk hormone replacement therapy alternative to estrogen therapy, effective in the treatment of menopausal symptoms and prevention of bone loss, but the evidence is controversial. This systematic review with meta-analysis summarizes the clinical trials of the tibolone effect on percentage change of bone mineral density in the lumbar spine, femoral neck, and total hip in postmenopausal women. The results show that tibolone 2.5 mg dose increases the percent change in bone mineral density compared with non-active controls at 24 months in lumbar spine and femoral neck, regardless of the scanner used to evaluate the bone mineral density. No difference was observed when 2.5 mg tibolone dose was compared with estrogen therapy at 24 months, and both treatments have a positive effect on the bone mineral density. In conclusion, tibolone increases bone mineral density compared to non-active controls, and there was no difference when it is compared to estrogenic therapy; thus, tibolone is an alternative treatment for menopausal symptoms and bone protection. ABSTRACT: Low bone mineral density (BMD) on postmenopausal women causes bone fragility and fracture risk. Tibolone seems to prevent bone loss. Therefore, this systematic review with meta-analysis synthesizes the tibolone effect on BMD percent change in lumbar spine (LS), femoral neck (FN), and total hip (TH) in postmenopausal women. Controlled trials that provided tibolone evidence on the efficacy of tibolone in preventing loss of BMD were included. Regarding the included studies, a pooled mean difference (MD) with 95% confidence intervals (95%CI) was estimated to determine the BMD percentage change. Eleven studies were identified and eight were included in the quantitative analysis. Tibolone at a dose of 2.5 mg increased BMD compared with non-active controls at 24 months in LS (MD 4.87%, 95%CI: 4.16–5.57, and MD 7.35%, 95%CI: 2.68–12.01); and FN (MD 4.85%, 95%CI: 1.55–8.15, and 4.21%, 95%CI: 2.99–5.42), with Hologic and Lunar scanners, respectively. No difference was observed when tibolone 2.5 mg dose was compared with estrogen therapy (ET) at 24 months, LS (MD −0.58%, 95%CI: −3.77–2.60), FN (MD −0.29%, 95%CI: −1.37–0.79), and TH (MD −0.12%, 95%CI: −2.28–2.53). Therefore, tibolone increases BMD in LS and FN compared to non-active controls, and there was no showed difference with ET.