OBJECTIVES: To describe Health Care Pathway and cost evaluation of patients with osteoporosis. METHODS: From ARNO Observatory, an Italian population database which provides comprehensive data referred to patient as: drug prescription, hospital discharges, imaging, lab tests and diagnostic examination, we analyzed a cohort of 185.489 subjects with osteoporosis in year 2011. A group without osteoporosis, matched by age, gender and LHU was compared to estimate differences in health costs and burden of disease. RESULTS: On a population of 5,313,167 over 40 years, we identified 185,489 patients treated with osteoporosis drugs (prevalence 3.5%). Prevalence rate is higher in female than male (6.1% vs 0.1%), modal value on 70-79 years. The average yearly cost/patient is 2.329€, 53% more than pair-matched group. This cost is due for 38.4% to drugs (31% specific drugs, 69% others), 42.8% to hospitalization and 18.8% to lab tests and diagnostic examinations. Most common specific drugs are bisphosphonates (81%), strontium ranelatum (21%), parathyroid hormone (1.2%) and SERMs (0.9%). A considerable percentage (24.8%) did not received vitamin D supplements in association. Compared to control group, patients with osteoporosis received more drugs expression of higher comorbidity (corticosteroids +70%, nervous system drugs +42%, PPI +33%) and were more frequently hospitalized, beyond fractures, for arthritis (+99%, p<0.01) and chronic bronchitis (+52%, p<0.01). Less than 50% of patients controlled their serum calcium levels in the last three years, 32% performed a densitometry and less than a fifth a radiography. CONCLUSIONS: A big data infrastructure is a valid instrument to evaluate patient care pathways, monitor the good practice of treatment and estimate cost of illness. In a large community setting of osteoporotic patients, the lack of supplement of vitamin D undermines the effectiveness of the specific pharmacological treatment. Despite low diagnostic approach, patients cost as much to the National Health System especially due to their frequent co-morbidities.