[Adherence to treatment of osteoporosis: an open question]

Effective drug therapies are available for a wide range of chronic medical conditions but adherence to medications is currently low with poor health outcomes. Evidences support that drug nonadherence is a universal problem more than a disease- and drug-specific problem. Although several methods have been proposed for the assessment of adherence, accurate measurement continues to be difficult and most studies produced inconsistent results on determinants of nonadherence. Osteoporosis is a chronic, asymptomatic illness before fracture, and poor adherence with antiresorptive medications is a significant problem in preventing its adverse consequences. Currently approved therapies for osteoporosis are effective and lower fracture risk, but about 50% of patients discontinues treatment within 12 months of initiation. Poor adherence has been associated with increased fracture risk and increased resource use and hospitalization. Causes of nonadherence to osteoporosis therapies are unknown. Some variables predictive of nonadherence have been found (older age, comorbidity, previous fractures, bone mineral density assessment, number of medications, institutionalisation) but explain only a small proportion of the variability of adherence. Patients may fail to remain on their medication for reasons that include inconvenience or complexity of dosing, high cost, side effects and lack of appreciation of the benefits of therapy. Potential solutions of poor adherence of osteoporosis may include a close monitoring of persistence and compliance, an improved relationship between physician and patient, and newer medications with extended dosing intervals.