Targeted Coaching to Improve Osteoporosis Therapy Adherence: A Single Arm Variation of the C-STOP Study

Background: In this pre-planned variation of the Comparing Strategies Targeting Osteoporosis to Prevent Fractures After an Upper Extremity Fracture (C-STOP) trial, we investigated whether adherence-specific coaching by the case manager (CM) further improved the adherence and persistence rates compared to those seen in the C-STOP trial. Methods: We conducted a prospective observational cohort study of community-dwelling adults 50 years or older who suffered an upper-extremity fracture and were not previously treated with osteoporosis medications, to assess whether a well-trained CM can partner with patients to improve adherence to and persistence with oral bisphosphonate intake. The primary outcome was adherence (taking > 80% of prescribed doses) to oral bisphosphonate intake at 12 months after study enrollment. Secondary outcomes included primary adherence to and 12-month persistence with oral bisphosphonate and calcium and vitamin D supplement intake at 12 months. Results: The study cohort consisted of 84 participants, of which 30 were prescribed an oral bisphosphonate. Twenty-two (73.3%) started treatment within 3 months. The adherence rate at 12 months was 77.3%. The persistence rate at 12 months was 95.5%. Of those not prescribed an oral bisphosphonate, 62.8% were taking supplemental calcium and 93.0% were taking supplemental vitamin D at 12 months. Depression was a significant predictor of 12-month non-adherence (adjusted odds ratio, 9.8; 95% confidence interval, 1.2–81.5). Conclusions: Adherence-specific coaching by a CM did not further improve the level of medication adherence achieved in the original C-STOP study. Importantly, these results can inform adherence in future intervention studies.