Ischaemic cardiac events and use of strontium ranelate in postmenopausal osteoporosis: A nested case-control study in the CPRD

Summary: We explored the cardiac safety of the osteoporosis treatment strontium ranelate in the UK Clinical Practice Research Datalink. While known cardiovascular risk factors like obesity and smoking were associated with increased cardiac risk, use of strontium ranelate was not associated with any increase in myocardial infarction or cardiovascular death. Introduction: It has been suggested that strontium ranelate may increase risk for cardiac events in postmenopausal osteoporosis. We set out to explore the cardiac safety of strontium ranelate in the Clinical Practice Research Datalink (CPRD) and linked datasets. Methods: We performed a nested case-control study. Primary outcomes were first definite myocardial infarction, hospitalisation with myocardial infarction, and cardiovascular death. Cases and matched controls were nested in a cohort of women treated for osteoporosis. The association with exposure to strontium ranelate was analysed by multivariate conditional logistic regression. Results: Of the 112,445 women with treated postmenopausal osteoporosis, 6,487 received strontium ranelate. Annual incidence rates for first definite myocardial infarction (1,352 cases), myocardial infarction with hospitalisation (1,465 cases), and cardiovascular death (3,619 cases) were 3.24, 6.13, and 14.66 per 1,000 patient-years, respectively. Obesity, smoking, and cardiovascular treatments were associated with significant increases in risk for cardiac events. Current or past use of strontium ranelate was not associated with increased risk for first definite myocardial infarction (odds ratio [OR] 1.05, 95% confidence interval [CI] 0.68-1.61 and OR 1.12, 95% CI 0.79-1.58, respectively), hospitalisation with myocardial infarction (OR 0.84, 95% CI 0.54-1.30 and OR 1.17, 95% CI 0.83-1.66), or cardiovascular death (OR 0.96, 95% CI 0.76-1.21 and OR 1.16, 95% CI 0.94-1.43) versus patients who had never used strontium ranelate. Conclusions: Analysis in the CPRD did not find evidence for a higher risk for cardiac events associated with the use of strontium ranelate in postmenopausal osteoporosis. © International Osteoporosis Foundation and National Osteoporosis Foundation 2013.