OBJECTIVES: Compliance to osteoporosis drugs is frequently very low leading to increased fracture risk in patients. This study examined the factors associated with fracture risk of post-menopausal osteoporotic (PMO) patients in Hungary with key interest in compliance. METHODS: This retrospective analysis used patients’ data from the National Health Insurance Fund Administration (NHIFA). Subjects were females, ≥50 years old with a diagnosis of osteoporosis (ICD-10 codes, M80 or 81), who started an osteoporosis drug prescription between Jan 2004 and Dec 2010. The relationship between all factors and fracture risk was assessed using a dynamic Cox regression model and the Andersen-Gill analysis estimating 95% confidence intervals. RESULTS: A total of 223,068 patients were analysed and 128,610 matched inclusion criteria for the fracture risk analysis with 46.9% older than 70 years; 6.4% had prior fractures at index date (i.e. the start of the analysis period). Analysis showed that compliant patients have an 18% (RR=0.82, CI=0.75-0.89) fracture risk reduction versus non-compliant patients. Moreover, patients older than 70 years had an increase in fracture risk of 26% (RR=1.26, CI=1.15-1.38) compared to patients aged 50-60 years old. Prior fractures were associated with a two-fold increased risk of a new fracture (RR=2.01, CI=1.76-2.30) and almost with a three-fold increased fracture risk (RR=2.91, CI=2.37-3.58) in patients with one and 2+ prior fractures respectively compared to patients with no prior fractures. Moreover, a relationship was found between any co-medication and fracture risk with a 9% (RR=1.09, CI=1.00-1.20) increase with one co-medication and a 32% (RR=1.32, CI=1.19-1.47) with 2+ co-medications compared to none. CONCLUSIONS: Age, any co-medication and prior fractures were associated with an increased relative risk of fracture. Compliance, however, was associated with protection against fracture (reduction of relative fracture risk).