A general method of compliance assessment using centralized pharmacy records. Description and validation

Area of Science:

• Pharmacology and Pharmaceutics
• Clinical Pharmacy Practice
• Health Services Research

Background:

• Patient compliance with long-term medications is crucial for treatment efficacy.
• Centralized pharmacy refill records offer a potential data source for compliance assessment.
• Existing methods for assessing compliance in managed care settings may be limited.

Purpose of the Study:

• To develop and validate a method for assessing patient medication compliance using centralized pharmacy refill data.
• To evaluate the correlation between medication compliance and clinical outcomes in patients with seizure disorders and hypertension.

Main Methods:

• Developed a compliance assessment method utilizing prescription refill data from centralized pharmacies.
• Validated the method using pharmacy records and clinical data from patients on phenytoin (anticonvulsant) and antihypertensive medications.
• Analyzed the relationship between compliance measures, plasma drug levels (phenytoin), and clinical markers (diastolic blood pressure).

Main Results:

• Compliance with phenytoin significantly correlated with mean plasma phenytoin levels.
• Compliance with antihypertensive medications correlated with diastolic blood pressure control.
• A significant proportion of patients received medication oversupplies, obscuring the direct compliance-effect relationship.
• The developed method identified a majority of seizure patients with subtherapeutic phenytoin levels as noncompliant.

Conclusions:

• The developed method for assessing medication compliance via refill data is feasible in managed care settings.
• This compliance assessment method demonstrates a valid correlation with drug effects.
• The approach shows potential utility in both clinical research and direct patient care for monitoring long-term medication adherence.