Highlights
- •Historic cohorts suggested that supply of inhaled medicines may exceed actual use.
- •This is the first study to directly compare medicine supply (MPR) against adherence.
- •Among 275 adults in 12 CF centres, MPR over-estimates adherence by a median of 14%.
- •Even with 20% contingency, mean annual cost of excess supply was £1,124/patient.
- •Excess supply cost was higher in those with adherence <50% (mean £2,017/patient).
Abstract
Background
Studies in separate cohorts suggest possible discrepancies between inhaled medicines
supplied (median 50-60%) and medicines used (median 30-40%). We performed the first
study that directly compares CF medicine supply against use to identify the cost of
excess medicines supply.
Methods
This cross-sectional study included participants from 12 UK adult centres with ≥1
year of continuous adherence data from data-logging nebulisers. Medicine supply was
measured as medication possession ratio (MPR) for a 1-year period from the first suitable
supply date. Medicine use was measured as electronic data capture (EDC) adherence
over the same period. The cost of excess medicines was calculated as whole excess
box(es) supplied after accounting for the discrepancy between EDC adherence and MPR
with 20% contingency.
Results
Among 275 participants, 133 (48.4%) were females and mean age was 30 years (95% CI
29-31 years). Median EDC adherence was 57% (IQR 23-86%), median MPR was 74% (IQR 46-96%)
and the discrepancy between measures was median 14% (IQR 2-29%). Even with 20% contingency,
mean potential cost of excess medicines was £1,124 (95% CI £855-1,394), ranging from
£183 (95% CI £29-338) for EDC adherence ≥80% to £2,017 (95% CI £1,507-2,526) for EDC
adherence <50%.
Conclusions
This study provides a conservative estimate of excess inhaled medicines supply cost
among adults with CF in the UK. The excess supply cost was highest among those with
lowest EDC adherence, highlighting the importance of adherence support and supplying
medicine according to actual use. MPR provides information about medicine supply but
over-estimates actual medicine use.
Keywords
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References
- Inhaled anti-pseudomonal antibiotics for long-term therapy in cystic fibrosis.Cochrane Database Syst Rev. 2018; 3CD001021
- Dornase alfa for cystic fibrosis.Cochrane Database Syst Rev. 2018; 9CD001127
- Accurate assessment of adherence: self-report and clinician report vs electronic monitoring of nebulizers.Chest. 2011; 140: 425-432
Hoo ZH, Totton N, Waterhouse S, et al. Real-world adherence among adults with cystic fibrosis is low – a retrospective analysis of the CFHealthHub digital learning health system. Chest Published Online First: 26 June 2021. doi: 10.1016/j.chest.2021.06.039.
- Exploring the implications of different approaches to estimate centre-level adherence using objective adherence data in an adult cystic fibrosis centre – a retrospective observational study.J Cyst Fibros. 2020; 19: 162-167
- Pulmonary medication adherence and health-care use in cystic fibrosis.Chest. 2014; 146: 142-151
- Variation in lung function as a marker of adherence to oral and inhaled medication in cystic fibrosis.Eur Respir J. 2017; 491600987
Trueman P, Lowson K, Blighe A, et al. Evaluation of the scale, causes and costs of waste medicines. Published November 2010. https://discovery.ucl.ac.uk/id/eprint/1350234/1/Evaluation_of_NHS_Medicines_Waste__web_publication_version.pdf. Date last accessed: December 18 2020.
NHS England. PSS3 cystic fibrosis supporting self-care PSS CQUIN indicator. Published March 2019. https://www.england.nhs.uk/publication/pss3-cystic-fibrosis-self-care-pss-cquin-indicator/ . Date last accessed: December 18 2020.
- Self-management intervention to reduce pulmonary exacerbations by supporting treatment adherence in adults with cystic fibrosis: a randomised controlled trial.Thorax Accepted:. 20 August 2021; https://doi.org/10.1136/thoraxjnl-2021-217594
- Beyond the expected: Identifying broad research priorities of researchers and the cystic fibrosis community.J Cyst Fibros. 2019; 18: 375-377
- The top 10 research priorities in cystic fibrosis developed by a partnership between people with CF and healthcare providers.Thorax. 2018; 73: 388-390
- Characterising burden of treatment in cystic fibrosis to identify priority areas for clinical trials.J Cyst Fibros. 2020; 19: 499-502
- Understanding Pseudomonas status among adults with cystic fibrosis: a real-world comparison of the Leeds criteria against clinicians’ decision.Eur J Clin Microbiol Infect Dis. 2018; 37: 735-743
- A comparison of data driven-based measures of adherence to oral hypoglycemic agents in Medicaid patients.AMIA Annu Symp Proc. 2014; 2014: 1294-1301
- Medication possession ratio: implications of using fixed and variable observation periods in assessing adherence with disease-modifying drugs in patients with multiple sclerosis.Patient Prefer Adherence. 2013; 7: 509-516
- An upper and lower bound of the medication possession ratio.Patient Prefer Adherence. 2017; 11: 1469-1478
- Longitudinal association between medication adherence and lung health in people with cystic fibrosis.J Cyst Fibros. 2011; 10: 258-264
- Rescue therapy within the UK cystic fibrosis registry: an exploration of predictors of intravenous antibiotic use amongst adults with CF.Respirology. 2018; 23: 190-197
- Tree-based, two-stage risk factor analysis for spontaneous abortion.Am J Epidemiol. 1996; 144: 989-996
UK Cystic Fibrosis Registry. Annual data report 2019. Published August 2020. https://www.cysticfibrosis.org.uk/the-work-we-do/uk-cf-registry/reporting-and-resources. Date last accessed: December 18 2020.
- Nebulised dornase alpha: adherence in adults with cystic fibrosis.J Cyst Fibros. 2002; 1: 255-259
- Adherence to the inhaled antibiotic treatment in patients with cystic fibrosis.Am J Respir Crit Care Med. 2013; 187: A4358
- Electronic monitoring reveals highly variable adherence patterns in patients prescribed ivacaftor.J Cyst Fibros. 2015; 14: 621-626
- Taking stock of medication wastage: unused medications in US households.Res Social Adm Pharm. 2015; 11: 571-578
- Evidence-based assessment of adherence to medical treatments in pediatric psychology.J Pediatr Psychol. 2008; 33: 916-936
- Medication adherence for resistant hypertension: Assessing theoretical predictors of adherence using direct and indirect adherence measures.Br J Health Psychol. 2018; 23: 949-966
- Medication adherence outcomes of 771 intervention trials: Systematic review and meta-analysis.Prev Med. 2017; 99: 269-276
- Role of habit in treatment adherence among adults with cystic fibrosis.Thorax. 2019; 74: 197-199
- Home delivery influences medicines possession ratio in adult cystic fibrosis.Thorax. 2018; 73: A162-A163
Article info
Publication history
Published online: September 23, 2021
Accepted:
September 4,
2021
Received in revised form:
September 1,
2021
Received:
April 22,
2021
Identification
Copyright
© 2021 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.
ScienceDirect
Access this article on ScienceDirectLinked Article
- Corrigendum to “Using a learning health system to understand the mismatch between medicines supply and actual medicines use among adults with cystic fibrosis” [J Cyst Fibros (2022), 21/2, 323-331]Journal of Cystic FibrosisVol. 21Issue 5
- PreviewThe authors regret an error has occurred in the description and calculation of dose-weighted composite MPR (dwcMPR) for participants on multiple medicines. We described dose-weighting according to the number of dispensed inhaled medications. In fact, the dose-weighting should be based on the number of prescribed inhaled medications to ensure there is no gap between the cMPR and electronic data capture (EDC) adherence if someone has indeed used all the medicines that were supplied. Therefore, the first step to calculate dwcMPR should have been: calculate the total prescribed doses of medicine by adding up of all individual values of daily prescribed dose × days.
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