Factors associated with adherence and persistence to bisphosphonate therapy in osteoporosis: a cross-sectional survey.

OBJECTIVE: To determine the factors associated with adherence and persistence to bisphosphonate therapy in osteoporosis. DESIGN: Cross-sectional survey. SETTING: National survey in the UK. PARTICIPANTS: Participants were recruited through the National Osteoporosis Society and advertisements in the press and on the radio and included 533 women over age 50 with osteoporosis who were currently taking or had taken bisphosphonate therapy within the previous 12 months. MAIN OUTCOME MEASURES: Self-reported factors influencing adherence and persistence to bisphosphonate therapy in osteoporosis: fracture history, pain, practical difficulties taking medication (frequency of dosing, dealing with comedications, impact on daily routine), perceptions of therapy, and concerns about bisphosphonate therapy. RESULTS: Adherence to bisphosphonate therapy was 48% and was associated with previous fracture [odds ratio (OR) 1.62, 95% confidence interval (CI) 1.14-3.02], concerns about medication (OR 1.49, 95% CI 1.01-2.20), and less dissatisfaction with medication (OR 0.65, 95% CI 0.44-0.97). Nonpersistence was associated with dissatisfaction with medication (hazard ratio (HR) 1.83, 95% CI 1.38-2.43), side effects (HR 3.69, 95% CI 2.74-4.97), and concerns about bisphosphonate therapy (HR 2.21, 95% CI 1.48-3.30). For both daily (HR 1.53, 95% CI 1.1-2.33) and weekly bisphosphonates (HR 1.90, 95% CI 1.17-3.07), practical difficulties taking bisphosphonate medication-in particular, too frequent dosing-were associated with nonpersistence. CONCLUSIONS: Self-reported nonadherence to daily and weekly bisphosphonates is independent of the decision to stop taking treatment (nonpersistence). Nonpersistence is associated with side effects and other factors that could be modified in clinical practice through education, information, and concordant partnerships.