In this episode of PodMD, dual-trained Respiratory, Sleep, and General Medicine Dr Harshan Jeyakumar will be speaking about an update in the management of asthma, including how asthma is diagnosed currently, the challenges in managing asthma, the role of phenotyping asthma, the treatment options available, when a GP should look to refer and more.
Please note this is a machine generated transcription and may contain some errors.
*As always, all in this PODMD podcast is intended for health professionals and the comments are of a general nature. Information given is not intended as specific medical advice pertaining to any given patient. If you have a clinical issue with one of your patients please seek appropriate advice from a colleague with expertise in the area.
Today I’d like to welcome to the PodMd studio Dr Harshan Jeyakumar
Dr Harshan Jeyakumar is a dual-trained Respiratory, Sleep, and General Medicine Physician working in South-East Melbourne and Gippsland.
Having graduated from Monash University in 2013, Dr Jeyakumar completed his internship and Basic Physician Training through Monash Health in 2018. Following this, he accepted a four-year dual training position in Respiratory and General Medicine through Monash Lung & Sleep and Latrobe Regional Hospital, receiving his Royal Australasian College of Physicians Fellowship in 2020. He then completed post-fellowship training in Acute & General Medicine (LRH) and a 12-month Sleep Fellowship (Monash Health)
Today, we’ll be discussing the latest updates in Asthma management
*We do hope you enjoy this podcast but please remember that the advice here is of a general nature and is not intended as specific advice about a given patient. The views and opinions expressed in this podcast are those of the doctor, not PodMD.
If you do have a patient on whom you require specific advice, then please seek advice from a colleague with appropriate expertise in that area.
Harshan, thanks for talking with us on PodMD today.
Harshan : Thank you for having me.
The topic of today’s discussion is an update in Asthma management. Harshan, to begin with, can you explain how asthma is diagnosed today?
Harshan: Certainly. So it’s important to match our clinical presentation for asthma toobjective measures and listeners will be well aware of the typical presentation of asthma being that of shortness of breath, cough, chest tightness and wheeze with very clear triggers such as changes in the weather, viral infections, increasing allergy exposure, such as in the spring months to pollen and dust as well as nocturnal symptoms. Increasingly, we’re finding a diagnosis of asthma in atypical settings, and it’s important to then really take a detailed history as to when these symptoms are occurring and matching that the risk of asthma.
Viral induced or viral triggered asthma is a very common presentation that may be the only time patients experience symptoms, but those symptoms can be debilitating in the setting of a virus and can linger for a long time after the initial viral infection. Part of our diagnosis of asthma today has shown an increased role for biomarker testing to phenotype the underlying asthma which is important in guiding our management strategies as these have improved over the time. In the last 12 to 24 months, we have noticed an increase in our presentation of asthma in patients post COVID-19 and this may include patients who had an underlying risk of asthma already prior to developing COVID-19 as well as patients who have only developed symptoms post their viral infection but have failed to improve.
How is asthma diagnosed currently?
Harshan: So as mentioned before, a clinical history and an examination is incredibly important and to lead to the increased suspicion for an asthma diagnosis on examination, we’re obviously listening for wheeze, and in particular it’s important to listen to the end of expiration as the signs may be very subtle. When we are suspicious of asthma, lung function testing is certainly warranted. And these may be the classical spirometry findings of an obstructive deficit with significant bronchodilator reversibility to Ventolin but more subtle features may be present, including that of a restrictive pattern in the setting of gas trapping. Inclusive, this may be prevalent in their response to Ventolin as well as evidence of an elevated gas transfer when corrected for alveolar volume may also be shown as a [inaudible].
If lung function testing is alone is not sufficient to clinch your diagnosis, we can perform block your provocation testing. That may be with a molecule such as mannitol, which is known to increase airway hyperreactivity. Or we could look to triggering the patient with a known trigger for them, such as exercise. In the GP setting, peaks flow has always been a readily available tool and we know that day-to-day variability in peak flow recordings of more than 8% does lead to a higher risk of asthma.
What are the key challenges faced by healthcare professionals in effectively managing asthma?
Harshan: So as we’ve been discussing, the diagnosis of asthma is not as simple as we once thought it was, and it’s important to recognise an asthma presentation versus that of another condition and some of those may include middle airway syndrome conditions such as vocal cord dysfunction or excessive dynamic airway compromise, which can mimic asthma in many ways. It’s also important to recognise comorbid conditions of asthma and other airway conditions, such as sinusitis, which can have overlapping symptoms. We are showing increase in importance in identifying the triggers for asthma, which would warrant an escalation of therapy, especially those with mild to moderate disease. And it’s also important to educate patients on the importance of their compliance, particularly to avoid fixed airway remodelling.
You mentioned the role of phenotyping asthma – could you explain this further and how it is done?
Harshan: So phenotyping asthma has always been conducted by respiratory physicians, but has increased in importance in the current day given the treatments we have available. We typically look at asthma as either type 1 or type 2 inflammation. Where Type 2 inflammation is more of an [inaudible] or allergic phenotype. There are some biomarkers that we can test for on blood test and this includes IGE both as a total IGE as well as allergen specific looking for specific triggers that patients may have whether that be dust, pollen, specific foods or aspergillus. In blood eosinophil count is also important to recognise and this it would help us phenotype asthma even in a normal eosinophil count as per the laboratories reference range. Typically we would recognise an ear cynical count of 0.3 in a patient who is not on corticosteroids or 0.15 in someone who is as having a higher risk of type 2 inflammation in the setting of their asthma.
Other tests that we can perform to help phenotype asthma include FENO or fraction of exhaled nitric oxide as well as skin prick testing looking for specific allergy responses. It’s important to recognise that these tests can be performed and be normal even in the setting of Type 2 inflammation. And so we would usually recommend performing the blood test at least twice, and to do so when off steroids and ideally at the start of a flare if possible for the most accurate results. Sometimes in the setting of significant sinus disease, nasal examination may be of benefit and this may include fibre optic nasal endoscopy and sinus imaging looking for evidence of polyposis.
Can you explain the most recent guidelines for management of mild-to-moderate asthma?
Harshan: Certainly. So in the last five to 10 years, the GINA guidelines for asthma, which are recognised worldwide, have been updated with an increase in reliance on dual inhaled corticosteroids and laba, which is typically in the setting of budesonide-formoterol or Symbicort as a first line reliever and inhaler for mild asthma. This has been reflected in the PBS with a listing for Symbicort as a mild asthma therapy first line.
We’ve also got evidence over the last five years that the addition of a long acting antimuscarinic agent has does help to prevent hospitalisation and exacerbations, and should certainly be considered in a group of people where an ICS laba combination alone is not sufficient. There is a role for escalating inhaler therapy during known triggers, particularly in those who are only using it as on an as needed basis. And most importantly, providing patients with a written action plan and educating on them on when to use this has been shown widely to improve both treatment responses as well as minimising hospitalizations and Ed presentations.
If asthma symptoms persist despite inhaler therapy, what are other important things to consider?
Harshan: So typically we would start at the underlying issues of inhaler technique and adherence and assess these before moving on further. We would also relook at the triggers that may be causing these symptoms and try to minimise these or avoid these as much as possible and it’s important to look beyond the standard triggers and think about things in the home as well as in the occupational setting that may be causing these symptoms. Smoking cessation is certainly important, and this may include the use of E-cigarettes or vapes, which are of increasing prevalence these days. This it’s also important to educate patients around the role for short acting beta agonists as well as reliever the therapy in general and make sure that they are using this in the appropriate settings that they understand when to use these and identify that there are other drivers for their concern, which may be things such as anxiety, which could be manifest in itself as chest tightness or shortness of breath as well.
Once we have gone through those, we also look to other known comorbidities which affect asthma control. Sinus disease is very commonly linked with asthma and certainly warrants treatment. In the same setting as trying to control asthma symptoms. Obstructive sleep apnoea has been known to affect asthma control, as has gastroesophageal reflux disease. Obesity certainly plays a role in asthma control and a weight loss strategy is important, recognising that this is quite difficult, particularly in patients with significant symptoms and finally, in patients with a significant allergy profile, desensitisation therapy should be considered.
How would you manage an exacerbation of asthma?
Harshan: So for mild exacerbations managed in the home setting, there’s certainly a role for escalating inhaler therapy. Particularly in those who are not already on a preventer to add this in. You could consider a short course of corticosteroids, which usually do not need a wean and can be conducted over five to seven days and then stop. And a preventer should certainly be commenced in anyone who’s had an exacerbation of asthma that’s required corticosteroid usage. If an action plan hasn’t been conducted or completed already at this point in time, that should certainly be considered during that exacerbation.
When should a GP refer for asthma management?
Harshan: So GP should refer for asthma management at any stage when they feel the patient would warrant from specialist respiratory input. In particular, though difficult to control asthma patients with recurrent exacerbations, or where there needs to be clarity around the diagnosis would all be valid reasons for referral. Respiratory physicians are also able to identify and optimise comorbidities that can aid in asthma control and can devise treatment plans for those who seem to be intolerant to standard therapy.
What other treatments can a respiratory physician offer for severe or difficult to control asthma?
Harshan: So in the current day we have a number of treatments available to us that have been shown to significantly improve asthma control as well as quality of life. Listeners may recognise these as biologic therapies which all target type 2 inflammation. We have 4 drugs currently available on the PBS, if prescribed by a respiratory physician or a specialist with expertise in asthma management as long as the patient needs certain criteria.
These four drugs are omalizumab, dupilumab, mepolizumab, and benralizumab, and they all target different pathways of type 2 inflammation. They all have different degrees of efficacy based on the area that they are targeting, but overall they reduce oral corticosteroid use, minimise exacerbations and hospitalizations and have been shown to improve symptom scores and quality of life. They are injectable agents with a interval dosing of between 2 weeks and eight weeks. Typically, the first doses are given in supervised settings.
And it’s important for GP’s to be aware of some of the side effects of these medications as they may be required to identify and treat these. Injection site reactions tend to be the most common side effect which are very easy to treat conservatively. Are but some of the more unique side effects, particularly that for dupilumab and the risk of conjunctivitis should be recognised.
Thank you for your time here today in the PodMD studio. To sum up for us, could you please identify the three key take home messages from today’s podcast on current asthma management?
Harshan: Certainly. So, number one would be that it is important to both confirm the diagnosis of asthma as well as trying to phenotype the disease profile which will drive management strategies. #2 is that managing the comorbidities that are linked to asthma is very important in optimising overall asthma control and #3, recognising that there are new therapies and treatment strategies available that have had excellent efficacy including the use of inhaled corticosteroids and long acting beta agonists as first line therapy as well as the opportunity to escalate to biologic therapy in the right patient.
Thanks for your time and the insights you’ve provided.
Harshan: Thank you