Abstract
Purpose
The purpose of this study was to evaluate and compare medication adherence to chronic therapies in older populations across different regions in Europe.
Methods
This explorative study applied a harmonized method of data extraction and analysis from pharmacy claims databases of three European countries to compare medication adherence at a cross-country level. Data were obtained for the period between January 1, 2010, and December 31, 2011. Patients (aged ≥65 years) who newly initiated to oral antidiabetics, antihyperlipidemics, or antiosteoporotics were identified and followed for over a 12-month period. Main outcome measures were medication adherence (medication possession ratio, [MPR]; implementation) and persistence on index treatment. All country-specific data sets were prepared by employing a common data input model. Outcome measures were calculated for each country and pooled using random effect models.
Results
In total, 39,186 new users were analyzed. In pooled data from the three countries, suboptimal implementation (MPR <80%) was 52.45% (95% CI: 33.43–70.79) for antihy-perlipidemics, 61.35% (95% CI: 52.83–69.22) for antiosteoporotics, and 30.33% (95% CI: 25.53–35.60) for oral antidiabetics. Similarly, rates of non-persistence (discontinuation) were 55.63% (95% CI: 35.24–74.29) for antihyperlipidemics, 60.24% (95% CI: 45.35–73.46) for antiosteoporotics, and 46.80% (95% CI: 36.40–57.4) for oral antidiabetics.
Conclusion
Medication adherence was suboptimal with >50% of older people non-adherent to antihyperlipidemics and antiosteoporotics in the three European cohorts. However, the degree of variability in adherence rates among the three countries was high. A harmonized method of data extraction and analysis across health-related database in Europe is useful to compare medication-taking behavior at a cross-country level.
Supplementary materials
Figure S1 Number of subjects excluded from the analysis according to selection criteria.
Table S1 Nonadherence rates (MPR <80%), in all three drug classes, by age groups and by country
Table S2 Non-persistence rates, in all three drug classes, by age groups and by country
Acknowledgments
The authors wish to thank the A1 Action Group members on Prescription and Adherence to Medical Plans of the European Innovation Partnership on Active and Healthy Ageing for their contributions. Editorial assistance was provided by Dr Melanie Gatt (PhD), an independent medical writer, on behalf of Springer Health care Communications. This was funded by the University of Naples Federico II, Naples, Italy.
Author contributions
All authors contributed toward data analysis, drafting and revising the paper and agree to be accountable for all aspects of the work.
Disclosure
The authors report no conflicts of interest in this work.