“Inhaler Use, Technique & Treatment Adherence for Severe Asthma” presented by Profs. Sinthia Bosnic-Anticevich & Tim Usherwood
As part of our ongoing seminar series, the Centre of Excellence in Severe Asthma hosted Profs. Sinthia Bosnic-Anticevich & Tim Usherwood on 15 August 2019.
The two seminar presentations focussed on:
- Inhaler Use & Technique
- Treatment Adherence for Severe Asthma [from 40:05 in recording]
Presentation Summary
Prof. Bosnic-Anticevich provides an overview of evidence that inhaler technique impacts on asthma disease outcomes. Her presentation includes an overview of technical determinants of inhaler technique, patient-related factors that matter and other considerations. She concludes with a discussion of what the future holds for inhaler devices in asthma.
Prof. Usherwood discusses treatment adherence and its relevance to asthma outcomes. Further, he discusses a range of approaches to assess and support optimal treatment adherence.
You may also be interested in learning more about Inhaler Technique and Adherence from the Severe Asthma Toolkit.
Key Points:
Inhaler Use & Technique (Prof. Sinthia Bosnic-Anticevich):
- The expectation is that each patient should be able to use each type of inhaler correctly, but poor inhaler technique is common
- Inhaler technique is emphasised in asthma guidelines based on a growing evidence-base linking poor technique with worse disease outcomes
- Poor inhaler technique is correlated with worse disease stability and increased hospital visits for asthma
- Interventions targeting inhaler technique can improve asthma control, lung function and quality of life (e.g. Basheti et al. 2017 JACI)
- Despite the recognised importance, studies assessing inhaler technique regularly report low rates of good technique among asthma patients (~10-40%) (e.g. Sanchis et al. 2016 CHEST)
- Aspects of the specific inhaler device can impact on effective technique and drug delivery to the lungs (e.g. aerosol velocity, aerosol duration, particle size and internal device resistance)
- Dry powder formulations (DPIs) must be inhaled quickly and forcefully to ensure effective drug delivery and the required effort differs between different devices
- Technique errors are common across all inhaler device types
- Critical errors (those that affect disease outcomes and treatment efficacy) include insufficient inhalation effort, incorrect head positioning and device actuation not corresponding with inhalation (Price et al. 2017 JACI)
- Patient characteristics impact on inhaler technique and use, including physical ability / disability, inspiratory effort, cognition, beliefs, attitudes and concerns
- A high proportion of patients do not take their medications everyday as recommended
- A high proportion of patients report that they perceive their inhaler technique to be good and find their inhalers easy to use (Jahedi et al. 2016 JAMPDD)
- Patient motivation and beliefs (e.g. the necessity of medications) are important aspects predicting effective inhaler use, while concerns about medications and side effects are associated with lower use
- Selection of the “ideal device” must be tailored to individual patient needs and should include consideration of factors from both the clinician and patient perspective
- Other factors to consider in severe asthma include reduced lung function, device polypharmacy and experience with devices
- Patients with reduced inspiratory flow are at increased risk of poor symptom control and asthma attacks, with decreased ability to use inhalers properly
- Prescription of multiple medications (≥3 devices; termed polypharmacy) is associated with future risk of asthma attacks in a population with severe asthma (McDonald et al. 2019, Respirology)
- Switching between (or adding-on) multiple different types of inhalers provides some carry-over of knowledge, but is associated with worse disease outcomes (Bosnic-Anticevich et al. 2018, J Asthma; Bosnic-Anticevich et al. 2016, Int J COPD)
- Automated electronic inhaler monitoring devices that track usage and identify errors in technique can be used to provide patient feedback, improve technique and help identify patients with treatment-refractory asthma (Sulaiman et al, 2018, ERJ), and may be useful for future clinical management
- Inhaler technique can be improved through education and training, but must be consistently revisited over time at every clinic visit
Treatment Adherence (Prof. Tim Usherwood):
- In many cases, asthma may appear to be difficult-to-treat as a result of modifiable factors (including poor adherence and inhaler technique)
- Treatment non-adherence may be intentional and result from either personal attributes and/or external constraints
- Intentional non-adherence in severe asthma may relate to a range of factors including patient perception of treatment necessity, uncertainty of effectiveness, safety concerns, advice from family/friends, motivation, satisfaction in asthma management and perceived ease of use (Foster et al. 2011 IMJ)
- Personal attributes that relate to adherence include poor inhaler technique skills, forgetfulness or cognitive impairment, depressive illness or poor understanding of the treatment plan
- External constraints affecting treatment adherence include medication costs, access issues and treatment regime complexity (e.g. number of inhalers, dosing frequency and differing device techniques)
- To improve adherence, it is important to ask about medication use in an open and collaborative way at every consultation (e.g. normalise poor adherence, ask specifically about recent inhaler usage) and review patient / dispensing records to inform discussions, when available
- Objectively measured treatment adherence is often lower than patient self-reported adherence rates (Foster et al. 2011 IMJ)
- Management of intentional non-adherence may include patient education, shared decision-making and motivational interviewing
- Addressing non-intentional poor adherence may include modification of treatment complexity, a detailed written action plan, pharmacist support, reminders (e.g. text messaging) and a check of inhaler technique at every visit
About the Presenters:
Prof. Sinthia Bosnic-Anticevich is an internationally recognised respiratory researcher in the area of inhaler use and quality use of respiratory medicines. Trained as a pharmacist and basic scientist, Professor Bosnic-Anticevich spent several years in the pharmaceutical industry before returning to the University of Sydney developing and implementing the first problem-based learning course in a pharmacy curriculum in Australia.
Prof. Tim Usherwood is Professor of General Practice and Head of Westmead Clinical School, The University of Sydney. His research focusses on the development and evaluation of interventions to improve health outcomes in chronic disease.
More information about Inhaler Technique and Adherence is available in the Severe Asthma Toolkit.
