Nationwide registry-based analysis of cardiovascular risk factors and adverse outcomes in patients treated with strontium ranelate

Abstract

National registers showed that a large proportion of patients treated with strontium ranelate have conditions that may now contraindicate use. The risk of death in strontium ranelate-treated patients was significantly higher than that seen in users of other osteoporosis drugs even after adjusting for cardiovascular risk factor profile.

Introduction: The European Medicines Agency (EMA) recently warned that strontium ranelate should be avoided in patients with ischaemic heart disease (IHD), peripheral vascular disease (PVD) or cerebrovascular disease (CVD), and in patients with uncontrolled hypertension. We investigated to what extent patients beginning strontium ranelate had cardiovascular conditions and determined the rates of MI, stroke and death.

Methods: Using the Danish National Prescription Database, we identified all 3,252 patients aged 50+ who began strontium ranelate in 2005-2007 and 35,606 users of other osteoporosis drugs as controls. Hospital contacts and causes of death were retrieved from national registers.

Results: Patients starting strontium were older than patients treated with other osteoporosis drugs and more likely to suffer from IHD, PVD or CVD (combined prevalence 19.2 % in female users and 29.5 % in male users). The adjusted risk of MI was not significantly increased (women: HR 1.05 [95 % CI 0.79-1.41, p = 0.73]; men: 1.28 [0.74-2.20, p = 0.38]). For stroke, the adjusted HR was 1.23 (0.98-1.55, p = 0.07) in women and 1.64 (0.99-2.70, p = 0.05) in men. All-cause mortality was higher in strontium users (women: adjusted HR 1.20 [1.10-1.30, p < 0.001]; men: adjusted HR 1.22 [1.03-1.45, p < 0.05]).

Conclusion: Patients treated with strontium ranelate have an unfavourable cardiovascular risk profile compared with users of other osteoporosis drugs. However, only the risk of death differed significantly from the rates observed in users of other osteoporosis drugs adjusted for risk factor profile. A large proportion of patients currently treated with strontium ranelate have conditions that would now be considered contraindications according to EMA.