Cost-effectiveness of enhancing adherence with oral bisphosphonates treatment in osteoporotic women: an empirical approach based on healthcare utilisation databases

Objective Adherence with bisphosphonates therapy is generally low. Enhancing adherence with bisphosphonates would be effective in achieving the full benefits of therapy albeit a growth in the expenditure for supporting incremented drug use is expected. The cost-effectiveness of enhancing adherence with oral bisphosphonates in a large population of osteoporotic women has been assessed in the current study. Design Retrospective cohort study. Setting Healthcare utilisation databases of Lombardy Region, Italy. Participants A cohort of 28？558 women aged 45？years or more, resident in the Italian Region of Lombardy, who were newly treated with oral bisphosphonates during 2003–2004, was followed for 6？years after index prescription. Outcome measures Fracture-free survival time, healthcare cost and incremental cost-effectiveness ratio (ICER) of enhancing adherence, that is, the additional cost that would be spent every year for gaining one fracture-free year as a consequence of enhancing adherence at a certain level. Results Enhanced adherence from 33% (baseline) to 80%, increased both fracture-free survivals from 970 to 973？years and healthcare costs from €118？000 to €265？000 every 1000 woman-years, with ICER value of €53？000 (95% CI €49？000 to €58？000). ICER values were lower for older women (€50？000; 95% CI €42？000 to €58？000) and for those suffering from at least a chronic comorbidity (€25000; 95% CI 95% CI €7000 to €47？000). Conclusions Enhancing adherence with oral bisphosphonates offers important benefits in reducing the risk of fracture, although at a substantial cost