Overactive bladder medication adherence when medication is free to patients.

Area of Science:

• Urology
• Pharmacology
• Health Services Research

Background:

• Overactive bladder (OAB) affects millions, necessitating medication adherence for effective management.
• Medication compliance is a known challenge in chronic disease management, often influenced by patient cost-sharing.

Purpose of the Study:

• To evaluate medication compliance for overactive bladder (OAB) treatments within a healthcare system where patients incur no direct medication costs.
• To compare OAB medication adherence metrics in a zero-copay system against existing literature from systems with patient cost-sharing.

Main Methods:

• Pharmacy dispensing records for antimuscarinic agents were analyzed from January 2003 to December 2006.
• Medication nonpersistence, switching, and adherence were assessed using Kaplan-Meier survival analysis for persistence duration.
• Data included 7,879 adult patients within the United States Military Health System National Capital Region.

Main Results:

• The medication nonpersistence rate was 35.1%, with 25.6% of patients switching medications or doses.
• The median medication possession ratio was 0.82 overall, higher in men (0.86) than women (0.81).
• Patients on tolterodine extended release showed higher nonpersistence than those on oxybutynin immediate release.

Conclusions:

• A significant proportion (35%) of patients did not refill OAB prescriptions, aligning with previous findings.
• Despite nonpersistence, other adherence indicators suggest improved compliance in a zero-copay environment compared to systems with copays.
• Healthcare system design and cost elimination may positively influence patient medication adherence for OAB.