Prescribing Trends of Osteoporosis Medications, Adherence and Persistence with Denosumab versus Alendronate: A Real-World Retrospective Study in China.

INTRODUCTION

Osteoporosis, a common metabolic bone disease with high fracture risk and heavy global burden, requires long-term medication adherence and persistence for fracture prevention, yet both remain suboptimal. Prescribing trends, adherence, and persistence data for denosumab and alendronate remain limited, especially in Chinese populations.

METHODS

This retrospective cohort study used hospital data. Patients aged ≥50 who newly initiated denosumab or alendronate in 2023-2025 were screened; 2025 initiators were excluded for insufficient 1-year follow-up. New users had no prior prescription of either drug since 2009. The proportion of days covered (PDC) was assessed, with good adherence defined as ≥80%. Persistence was time from initiation to discontinuation, with >60-day gap after coverage end defining discontinuation for both drugs. Propensity score matching (PSM) balanced baseline characteristics. Multivariable logistic regression and Kaplan-Meier survival analysis compared adherence and persistence.

RESULTS

A shift in prescribing from oral to injectable formulations, with alendronate decreasing by 44% and denosumab increasing by 94% in 2023-2025. Denosumab demonstrated greater persistence and adherence than alendronate. The 1-year persistence rate was 46.28% (95% CI: 41.88%-50.80%) for denosumab vs 2.89% (95% CI: 1.60%-4.79%) for alendronate, with a 90.80% lower risk [HR: 0.092 (95% CI: 0.077-0.110), p < 0.001]. PDC was 0.530 (IQR: 0.493-0.975), adherence rate 46.90% (227/484) for denosumab vs 0.077 (IQR: 0.077-0.153), 2.48% (12/484) for alendronate; adherence was 41.29-fold higher with denosumab (95% CI: 22.41-76.07, p < 0.001). Multivariate analysis showed hypertension and fracture history with better adherence and persistence; inpatient status was associated with poorer persistence and adherence; and female sex with poorer persistence (all p < 0.05).

CONCLUSIONS

A shift from oral to injectable formulations was observed. Denosumab was associated with higher persistence and adherence than alendronate. Hypertension and fracture history were associated with better persistence and adherence, whereas inpatient status was associated with poorer persistence and adherence. Female sex was associated with poorer persistence without affecting adherence.