Oral bisphosphonate prescription and non-adherence at 12 months in patients with hip fractures treated in an acute geriatric unit

A poorer functional status at the time of fracture is a predictor of non-adherence to oral bisphosphonates initiated after a hip fracture, and suggests further opportunities for optimization of secondary fracture prevention in this high-risk population.

INTRODUCTION

Low adherence to treatment is a problem in post-fracture secondary prevention. We aimed to analyze the prognostic factors (related and predictive) associated with non-adherence to oral bisphosphonate prescription for hip fracture due to bone fragility (HFBF) 12 months after discharge from an acute geriatric unit.

METHODS

Prospective study of bivariate data analyzing related and multivariate factors predicting non-adherence of oral bisphosphonates at 12 months after treatment for HFBF. The statistical study was performed with SPSS 19.0.0.

RESULTS

We attended 368 patients with HFBF. At discharge, oral bisphosphonates were prescribed to 226 (61.42%) patients. At 12 months, we followed up 160 (70.7%) patients, 104 (65%) of whom had non-adherence to oral bisphosphonates. Bivariate analysis (adherent vs. non-adherent): age (83.79 ± 5.82 vs. 85.78 ± 5.80, p = .029); Lawton and Brody Index (4.29 ± 3.40 vs. 2.67 ± 3.31, p = .004); baseline Barthel Index (BI) (85.89 ± 21.99 vs. 74.18 ± 26.70) (p = .004); BI at admission (18.84 ± 10.00 vs. 14.47 ± 11.71, p = .004); BI at discharge (34.20 ± 15.40 vs. 27.45 ± 16.71, p = .011); baseline Functional Ambulation Classification (5.66 ± 0.98 vs. 5.43 ± 0.99, p = .025). Multivariate analysis: BI 0.980 (0.965-0.995, p = .007). Discriminatory capacity of the AUC model (± 95% CI): 0.634 (0.545-0.722).

CONCLUSIONS

At 12 months, there was low adherence to treatment with oral bisphosphonates in our model. A lower BI prior to treatment is a predictive factor for non-adherence treatment with oral bisphosphonate.