# Compliance With Parathyroid Hormone Analog Medications at a Single Osteoporosis Treatment Center

## TL;DR

This study examines how well patients stick to parathyroid hormone treatments for osteoporosis and finds that side effects and financial issues are major reasons for stopping treatment.

## Contribution

The study identifies specific factors affecting compliance with parathyroid hormone analogs and compares two medications in a single-center setting.

## Key findings

- 54% of patients completed the full 24-month treatment course.
- Abaloparatide patients had higher non-compliance rates and shorter time to non-compliance compared to teriparatide patients.
- Early non-compliance was mainly due to side effects, while late non-compliance was often due to financial reasons.

## Abstract

Background

Osteoporosis is the most common metabolic bone disease and is more common in female patients and the elderly. The costs associated with osteoporotic fractures present a significant burden on the healthcare system. While effective pharmacologic therapy exists, treatment initiation and compliance remain suboptimal, leading to increased morbidity. This study evaluated compliance with parathyroid hormone analogs and identified reasons for non-compliance.

Methods

This was a retrospective study of patients prescribed parathyroid hormone analogs from a single osteoporosis clinic from 2017 to 2022. Of the 100 patients included, 42 were prescribed teriparatide and 58 were prescribed abaloparatide. The primary outcomes of interest were continued compliance with medication therapy and reasons for non-compliance. The secondary outcome of interest was fracture rate. Univariate analyses were performed to identify differences between the two groups, and a Kaplan-Meier curve was generated to show overall compliance.

Results

The average treatment duration was 15.5 months (95% CI: 13.5-17.4 months); 54 (54%) patients completed the full 24-month medication course. Abaloparatide patients had higher rates of non-compliance than teriparatide patients (33 (56.9%) vs. 13 (31.0%); p=0.018) and had a significantly shorter time to non-compliance (4.1 ± 4.6 vs. 8.8 ± 6.4 months; p=0.027). There was a significant difference in reason for non-compliance between early (≤3 months) and late non-compliant patients (p=0.001). About 19 (79.2%) patients were non-compliant early because of side effects, while 10 (45.5%) patients were non-compliant late because of financial reasons. There were no differences in fracture rates between the two groups.

Conclusion

More than half of the patients in this study completed the full two-year course of treatment, and the average duration of treatment was over 15 months. The overall fracture rate during and after treatment was low. Financial concerns and side effects were the most common reasons for non-compliance. An additional study would be needed to evaluate methods for improving patient compliance with parathyroid hormone analogs.