Does a Patient-Directed Financial Incentive Affect Patient Choices About Controller Medicines for Asthma? A Discrete Choice Experiment and Financial Impact Analysis
In Australia, many patients who are initiated on asthma controller inhalers receive combination inhaled corticosteroid/long-acting beta2-agonist (ICS/LABA) despite having asthma of sufficiently low severity that ICS-alone would be equally effective and less costly for the government.
We conducted a discrete choice experiment (DCE) in a nationally representative sample of adults (n = 792) and parents of children (n = 609) with asthma. Mixed multinomial models were estimated and calibrated to reflect the estimated market shares of ICS-alone, ICS/LABA and no controller. We then simulated the impact of varying patient co-payment on demand and the financial impact on government pharmaceutical expenditure.
Preference for inhaler decreased with increasing costs to the patient or government, increasing chance of a repeat visit to the doctor, and if fewer symptoms were present. Adults preferred high-strength controllers, but parents preferred low-strength inhalers for children (general beneficiaries only). The DCE predicted a higher proportion choosing controller treatment (89%) compared to current levels (57%) at the current co-payment level, with proportionately higher uptake of ICS-alone and a lower average cost per patient [32.73 Australian dollars (AU$) c.f. AU$38.54]. Reducing the co-payment on ICS-alone by 50% would increase its market share to 50%, whilst completely removing the co-payment would only have a small marginal impact on market share, but increased average cost of treatment to the government to AU$41.04 per person.
Patient-directed financial incentives are unlikely to encourage much switching of medicines, and current levels of under-treatment are not explained by patient preferences. Interventions directed at prescribers are more likely to promote better use of asthma medicines.
The authors would like to acknowledge the valuable input from advisory group members throughout this project.
Compliance with Ethical Standards
Ethical approval and informed consent
Ethical approval was granted by the University of New South Wales Human Research Advisory Panel Ethics Committee (Approval number # HREAP 2014-7-34). All procedures were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Informed consent was obtained from all individual participants.
The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.
This study was funded by a National Health and Medical Research Council (NHMRC) partnership grant (GNT1077204) with matching funding (including in-kind in the form of staff time) from Asthma Foundation NSW and Asthma Australia Inc. (both now part of the new merged Asthma Australia Limited) and from NPS MedicineWise. TL is supported by a NHMRC Early Career (Sidney Sax) Fellowship (APP 1110230). SJ is supported by an NHMRC Principal Research Fellowship (APP111943). ER is supported by an NHMRC Senior Principal Research Fellowship (APP1110139).
Conflict of interest
HKR reports receiving independent research grants and study inhalers from GlaxoSmithKline and AstraZeneca, honoraria from AstraZeneca, GlaxoSmithKline, Merck and Novartis for participation on a data safety monitoring board, and honoraria for providing independent medical advice on advisory boards or steering committees from AstraZeneca, GlaxoSmithKline, Novartis and Boehringer Ingelheim, and for providing independent medical education at symposia funded by AstraZeneca, GlaxoSmithKline, Novartis, Teva, Boehringer Ingelheim and Mundipharma. HKR is Chair of the Global Initiative for Asthma (GINA) Scientific Committee and a member of the Australian Asthma Handbook Guidelines Committee. GBM reports non-financial support from GlaxoSmithKline PLC, grants from AstraZeneca, outside the submitted work. MG reports income from multiple pharmaceutical and device manufacturers outside the submitted work, specifically, non-financial support from Bird Healthcare, non-financial support from GSK, non-financial support from Astra Zeneca, grants from GSK, grants from Astra Zeneca, grants from Sanofi, grants from Bayer, and grants from Cipla. TL, NJZ, ER, AF, AH, KL, and SJ have no conflicts of interest related to the contents of this article.
All authors contributed to the conception or design of the work; acquisition, analysis or interpretation of data for the work; drafting or critical revision for intellectual content; final approval of the submitted version; and are accountable for all aspects of the work.
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