Background and importance Osteoporosis and atherosclerosis share similar risk factors and pathological mechanisms in developing cardiovascular events. Two long acting injections, denosumab and zoledronate, are commonly used for osteoporosis treatment due to better persistence in therapy, but comparisons of long term cardiovascular events between these two drugs remain unclear, especially in the elderly Asian population.

Aim and objectives To compare the cardiovascular event risk between denosumab and zoledronate in patients with osteoporosis.

Material and methods We conducted a retrospective cohort study analysing the largest multi-institutional electronic medical records database in Taiwan, covering 1.3 million individuals (6% of the Taiwan population). We included osteoporotic patients aged over 65 years without cardiovascular events at baseline, newly receiving denosumab or zoledronate during 2015–2016, and used 1:1 propensity score matching to ensure balanced characteristics between the two groups. The primary study outcome was the composite of cardiovascular events, including cardiovascular death, myocardial infarction, ischaemic stroke and heart failure. We followed these patients until the occurrence of cardiovascular events, last clinical visit or the end of the database (31 December 2019) and performed a Cox proportion hazard model to compare the cardiovascular event risks between denosumab and zoledronate.

Results We included 3908 denosumab and 803 zoledronate new users with a mean age of 75.7 (SD 9.4) years, of whom 19.8% were men. After matching, baseline characteristics, including sex, age, comorbidities and concomitant medications, were balanced between the denosumab and zoledronate new users. After a median follow-up of 3.8 years, we identified 59 and 61 cardiovascular events in patients with denosumab and zoledronate, respectively. The incidence rate of cardiovascular events was similar between denosumab and zoledronate (19.4 vs. 20.0 per 1000 patient years) which yielded a hazard ratio of 0.97 (95% CI 0.68 to 1.39).

Conclusion and relevance Denosumab and zoledronate had similar risks for cardiovascular events in the Asian elderly population with osteoporosis. Further large scale studies are suggested to confirm our findings.

Conflict of interest No conflict of interest