Analysis of the costs and consequences of adherence to therapy in hip fracture patients. Results of a longitudinal analysis of administrative databases

The aim of this study, a retrospective cohort analysis, was to calculate the costs and consequences of exposure to and compliance with drug treatments recommended for refracture prevention in post-menopausal women with hip fracture. All women aged ≥65 years and admitted to hospital with a main or secondary diagnosis of hip fracture in the period 1 January 2006 - 31 December 2008 were included. These patients were classified as exposed /not exposed to a drug treatment for fracture prevention. Adherence to treatment was calculated in the group of patients treated with bisphosphonates. The following items were considered in the cost analysis: drug treatments supplied, diagnostic tests administered and hospital admissions recorded during the observation period. In total, 5,167 patients were included in the analysis, of whom only 33.9% received drug therapy post hip fracture; of those treated with bisphosphonates, only 21.1% were found to have adhered to the treatment. Exposure to drug treatment reduced the risk of refracture by 39.5% and the risk of death by 55.1%. The mean cost increases observed in the patients who, according to indication, were exposed to drug treatment (+ € 256) or submitted to a diagnostic test (+ € 40) were offset by a sizeable reduction in costs of hospitalisation for refracture (- € 703). Drug treatment for the prevention of bone refractures in hip fracture patients was found to be effective in reducing the risk of refracture and death, and cost-effective, reducing overall patient management costs.