Upper gastrointestinal safety and tolerability of oral alendronate: A meta-analysis

Osteoporosis (OP), which is a common bone disease associated with reduced bone mineral density and disordered bone microstructure, may result in an increased risk of bone fracture. The present study aimed to investigate the frequency of alendronate (Aln)-associated upper gastrointestinal tract adverse events (GIAEs) in postmenopausal women with OP. The following databases were searched in order to identify relevant studies: Medline (using PubMed as the search engine), Embase, the Web of Science and the Cochrane Central Register of Controlled Trials (up to December 2014). Studies were selected for inclusion if they were randomized, double-blind, placebo-controlled trials, which had investigated the safety of Aln versus a placebo for the treatment of postmenopausal women with OP. The primary outcomes of the included studies were total adverse events (AEs) and upper GIAEs, whereas individual upper GIAEs were considered as secondary outcomes. The general characteristics and outcomes of each study were abstracted by two independent researchers, and Review Manager 5.3 software was used for data syntheses and the meta-analysis. A total of nine studies, including 15,192 randomized patients, met the inclusion criteria and contributed to some or all of the meta-analysis outcomes. The Mantel-Haenszel method was used to calculate risk ratios, and their 95% confidence intervals (CI) were determined using either the fixed or random effects model, depending on the level of heterogeneity. The relative risk (95% CI) of AEs associated with Aln treatment, as compared with the placebo group, was 1.01 (0.97-1.06), and the relative risk (95% CI) of discontinued Aln treatment due to AEs was 1.04 (0.91-1.19). In addition, the relative risk (95% CI) of upper GIAEs was 1.02 (0.99-1.06), and the relative risk (95% CI) of discontinued Aln treatment due to upper GIAEs was 1.23 (0.97-56). In addition, these results remained robust to sensitivity analyses. The results of the present study suggested that Aln has a good GI tract tolerability, and that daily treatment with 10 mg Aln sodium does not increase the risk of GIAEs in postmenopausal women with OP.