Klop C, Welsing PM, Elder s PJ, Overbeek JA, Souverein PC, Burden AM, van Onzenoort HA, Leufkens HG, Bijlsma JW, deVries F. Osteoporos Int. 2015 Jun; 26 (6): 1831-40.
Long-term persistence with anti-osteoporosis drugs and determinants for discontinuation among fracture patients were examined. Persistence was 75.0 and 45.3 % after 1 and 5 years, respectively. Those aged >/=80 years were at increased risk of earlydiscontinuation. Within 1 year after discontinuation, 24.3 % restarted therapy, yet 47.0 % persisted for 1 year. INTRODUCTION: The risk of osteoporotic fracture can effectively be reduced with use of anti-osteoporosis drugs. However, little is known about persistence with these drugs after fracture where subsequent fracture risk is high. The aims were to determine long-term persistence with anti-osteoporosis drugs among fracture patients, including its determinants, and to describe restart and subsequent persistence. METHODS: A cohort study was conducted within the Dutch PHARMO Database Network. Patients aged >/=50 years (n = 961) who received anti-osteoporosis drugs within 1 year after fracture, but not in the preceding year, were included (2002-2011). Persistence (defined as the proportion on treatment) and the proportion restarting after discontinuation were estimated using Kaplan-Meier analyses. Time-dependent Cox regression was used to identify determinants of non-persistence including age, sex,initial dosage regime, fracture type, comorbidities, and drug use. RESULTS: Persistence with anti-osteoporosis drugs was 75.0 % (95 % confidence interval (CI) 72.0-77.7) and 45.3 % (95 % CI 40.4-50.0) after 1 and 5 years, respectively. A significant determinant of non-persistence was age >/=80 years (reference 50-59 years: adjusted hazard ratio [adj. HR] 1.65; 95 % CI 1.15-2.38). This effect was not constant over time (=360 days following initiation: adj. HR 2.07; 95 % CI 1.27-3.37; >360 days: adj. HR1.08; 95 % CI 0.62-1.88). Within 1 year after discontinuation, 24.3 % (95 % CI 20.1-29.2) restarted therapy, yet 47.0 % persisted for 1 year. CONCLUSIONS: This study identified suboptimal persistence with anti-osteoporosis drugs among fracture patients.Major target groups for measures aimed to improve persistence may be those aged >80 years and those restarting therapy.