BACKGROUND: Electronic prescribing records can enable exploration of medication adherence, but analysis decisions may influence estimates and require alignment to new consensus-based definitions.
OBJECTIVE: To compare different computations of inhaled corticosteroid (ICS) implementation in a primary care asthma population initiating ICS therapy when assessed within episodes of persistent use, and examine longitudinal variation in implementation.
METHODS: A historical cohort study was conducted on UK's Optimum Patient Care Research Database. Eligible patients had physician-diagnosed asthma, initiated ICS therapy, and had 3 or more years of continuous registration. ICS treatment episodes were constructed on the basis of 3 definitions, permitting 30-, 90-, and 182-day gaps between prescriptions. Implementation was estimated using 2 continuous medication availability (CMA I and II) definitions to explore effects of carryover of previous prescriptions in 4 observation windows: 6, 8, 12, and 24 months. Impact of methodology was assessed by descriptive statistics, linear mixed models, and measures of agreement.
RESULTS: A total of 13,922 eligible patients (mean age, 39.9 years; 48.7% men) were identified. For CMA I, permitting a 90-day gap, mean ICS implementation for the 2-year period was 89.3% (±16.0%; range, 14.4%-100%). Sensitivity analyses with 30- and 182-day gaps resulted in increased (97.0% ± 7.2%) and decreased (81.1% ± 21.6%) estimates. CMA II produced estimates with varying concordance (0.69-0.87). Substantial variance was found between and within patients (intraclass coefficient, 0.30-0.36).
CONCLUSIONS: Different analysis choices resulted in substantial variation in implementation estimates, highlighting the need for transparent and clinically relevant methododology. Distinguishing between (non)persistence and implementation is important in clinical practice, and may require different interventions in routine consultations.
|Number of pages||9|
|Journal||The journal of allergy and clinical immunology. In practice|
|Early online date||1 Nov 2016|
|Publication status||Published - 1 Mar 2017|
The authors would like to thank Hilary Pinnock, Nemr Eid, Randal Brown, Miguel Román Rodriguez, Janet Holbrook, Michelle Eakin, Cynthia Rand, and Iain Small for reviewing the study protocol.
This study was funded by the Respiratory Effectiveness Group, an international, investigator-led, not-for-profit, real-life respiratory research and advocacy initiative (www.effectivenessevaluation.org).
Conflicts of interest: P. C. Souverein, E. S. Koster, and A. L. Dima have received research support from the Respiratory Effectiveness Group. G. Colice is employed by and has stock/stock options in AstraZeneca. E. van Ganse has received research support from personal fees from ALK Abello, Bayer, Bristol-Myers Squibb, GlaxoSmithKline, Merck Sharp, and Dohme and has received personal fees from AstraZeneca, Boehringer Ingelheim, Intercontinental Marketing Services (IMS), and LASER. A. Chisholm declares no relevant conflicts of interest. D. Price is on the boards for Aerocrine, Almirall, Amgen Inc, AstraZeneca plc, Boehringer Ingelheim, Chiesi, Meda, Mundipharma, Napp, Novartis International AG, and Teva (fees paid to Research in Real Life Ltd); has received consultancy fees from Almirall, Amgen Inc, AstraZeneca plc, Boehringer Ingelheim, Chiesi, GlaxoSmithKline plc, Meda, Mundipharma, Napp, Novartis International AG, Pfizer, Inc, and Teva (fees paid to Research in Real Life Ltd); has received research support from UK National Health Service, British Lung Foundation, Aerocrine, AKL Ltd, Almirall, AstraZeneca plc, Boehringer Ingelheim, Chiesi, Eli Lilly, GlaxoSmithKline plc, Meda, Merck & Co., Inc, Mundipharma, Napp, Novartis International AG, Orion, Pfizer, Inc, Respiratory Effectiveness Group, Takeda, Teva, and Zentiva; has received lecture fees from Almirall, AstraZeneca plc, Boehringer Ingelheim, Chiesi, Cipla, GlaxoSmithKline plc, Kyorin, Meda, Merck & Co., Inc, Mundipharma, Novartis International AG, Pfizer, Inc, Skyepharma, Takeda, and Teva (fees paid to Research in Real Life Ltd); has received payment for manuscript preparation from Mundipharma and Teva (fees paid to Research in Real Life Ltd); has a patent with AKL Ltd for Phytopharmaceuticals; has received payment for development from GlaxoSmithKline and Novartis International AG (fees paid to Research in Real Life Ltd); has stock in AKL Ltd; has received travel support from Aerocrine, Boehringer Ingelheim, Mundipharma, Napp, Novartis International AG, and Teva (fees paid to Research in Real Life Ltd); has received funding for patient enrollment or completion of research from Almirall, Chiesi, Teva, and Zentiva (fees paid to Research in Real Life Ltd); is a peer reviewer for the grant committees of the Medical Research Council, Efficacy and Mechanism Evaluation programme; and owns 80% of Research in Real Life Ltd (which is subcontracted by Observational and Pragmatic Research Institute Pte Ltd), 75% of the social enterprise Optimum Patient Care Ltd, and 75% of Observational and Pragmatic Research Institute Pte Ltd.
- inhaled corticosteroids
- cohort study