Endocrine Abstracts

Objective: Menopausal hormone therapy (MHT) is efficacious in reducing the risk of vertebral, non-vertebral and hip fractures, irrespective of age, falls risk or baseline FRAX probability. However, the optimal sequential anti-osteoporotic treatment after MHT discontinuation has not yet been designated. This systematic review aimed to obtain the best evidence regarding the effect of antiresorptive or osteoanabolic treatment on bone mineral density (BMD) and/or fracture risk following MHT.

Methods: A comprehensive search was conducted in PubMed, Scopus and Cochrane databases up to October 31, 2023. Randomized-controlled trials (RCTs) and observational studies conducted in postmenopausal women were included.

Results: After the exclusion of duplicates, 717 studies were identified. Two were eligible for qualitative analysis, one RCT and one retrospective cohort study. The RCT showed that alendronate 10 mg/day for 12 months further increased lumbar spine (LS) BMD by 2.3% following MHT, whereas a mean loss of 3.2% was observed in the placebo group (mean difference: +5.5% between groups). Regarding femoral neck (FN), alendronate maintained BMD, whereas it decreased by 1.4% in the placebo group (n=144). Alendronate also decreased bone anabolic and resorption markers by 47% and 36%, respectively. In the retrospective study (n=34), raloxifene 60 mg/day increased both LS and FN BMD at 12 months by 3% and 2.9%, respectively. A limitation of this study was the lack of a placebo group. No fractures were reported.

Conclusions: Anti-resorptive therapy with either a bisphosphonate (i.e., alendronate) or raloxifene could be considered a sequential anti-osteoporosis therapy after MHT withdrawal, since they have shown in studies to further increase BMD. However, no safe conclusions can be drawn from the existing literature.