Asthma Diagnosis and Management Algorithm for Primary Care

Scope

This guideline offers recommendations for the diagnosis, education, and management of mild to moderate asthma in primary care settings, catering to both pediatric and adult patients. It serves as an updated resource, replacing previous guidelines specifically for adults and children from 2015.

Please note that severe asthma and severe exacerbations fall outside the scope of this guideline.

Navigation

The majority of information concerning asthma diagnosis and management is consistent across all age groups. However, certain age-specific considerations for diagnosis and medication are highlighted with icons next to each section: This icon indicates guidance specific to children under 6 years of age.

Key Recommendations for Asthma Diagnosis and Management

Diagnosis

• For children under 6 years old: A presumptive diagnosis is appropriate if there is a positive response to a therapeutic trial of salbutamol after an office visit where the child presents with audible wheezing.
• For patients over 6 years old: Confirmation of asthma with spirometry remains the gold standard.

Medication

• For adults with very mild asthma: PRN (pro re nata, or as needed) Budesonide formoterol is recommended as a first-line treatment.
• For children with very mild asthma at lower risk of exacerbations: PRN short-acting beta agonists (SABAs) are recommended as first-line therapy.
• For children with very mild asthma at higher risk of exacerbations: Daily inhaled corticosteroids (ICS) are recommended as first-line treatment.
• Before prescribing systemic steroids, always assess the patient’s current asthma management. Be aware that even as few as four short courses of systemic steroids over a lifetime can be associated with significant adverse events.
• Initiate treatment at the step most appropriate for the patient’s initial asthma severity.
• Reassess asthma control and exacerbation risk at least every 6 months. Aim to decrease medication doses to the lowest effective dose to maintain control.

Management

• Develop a written asthma action plan with every patient and/or their family. Review and reassess this plan regularly.
• Regularly confirm that patients are using their inhalers correctly and as prescribed, especially if they are not responding to treatment.

Environmental Impact and Climate Change

• Where clinically appropriate, consider prescribing lower-environmental impact medication options. Metered-dose inhalers (MDIs) significantly contribute to climate change, which in turn can worsen asthma.
• Prepare patients for climate events, such as wildfires, which can severely exacerbate asthma symptoms.

Epidemiology of Asthma

In British Columbia, the prevalence of asthma has been steadily increasing over the past two decades.1 It has risen from 8% of the population in 2001/02 to 12% in 2021/22.2 In 2015, asthma exacerbations in Canada led to 70,000 hospitalizations and 250 deaths nationally.3,4 Effective disease management and consistent primary care follow-up after acute care episodes are crucial in reducing hospital readmissions.5

The direct costs associated with asthma care tend to decrease as children age and hospitalizations become less frequent. The highest healthcare costs are concentrated among individuals with severe or uncontrolled asthma.

Asthma Risk Factors

Several factors increase the risk of developing asthma, including but not limited to:6

• Family history of asthma or allergies
• Presence of allergies (allergic sensitization)
• Exposure to poor air quality and environmental pollutants
• Early childhood viral respiratory infections
• Obesity

Asthma Diagnosis in Primary Care

Diagnosing asthma involves assessing both the patient’s clinical history and physical examination findings for compatibility with asthma, along with objective evidence of reversible airflow obstruction.7

For patients with a pre-existing asthma diagnosis, it is essential to ensure that variable airflow obstruction is documented in their records. Refer to Table 2. Diagnosis of asthma for a detailed overview of asthma diagnostic criteria by age group.

History and Physical Examination

The clinical features of asthma (outlined in Table 1. Clinical features that impact the probability of asthma diagnosis) can often mimic or overlap with symptoms of other respiratory conditions. It is crucial to consider and rule out other possible diagnoses before confirming an asthma diagnosis (see Differential Diagnosis).

Wheezing

Wheezing is the most specific physical sign associated with asthma. Since patients may describe various sounds as ‘wheezing’, it is important to clarify the nature of the sound and ideally confirm the presence of wheezing during a physical examination. Asthma-related wheezing is typically characterized as a high-pitched whistling sound, most commonly heard during exhalation.

Notably, adults may be less likely to present with audible wheezing upon auscultation.

Non-Wheezing Asthma Symptoms

Besides wheezing, other common symptoms of asthma include chest tightness, shortness of breath (dyspnea), and cough.7 Patients who report experiencing more severe symptoms in the morning or overnight are more likely to have asthma.9

It’s important to remember that asthma signs and symptoms can be transient and may not be present during a physical examination.

Diagnostic Considerations for Asthma in Children Under 6 Years Old

Asthma in children under 6 years of age is often characterized by symptoms triggered primarily by viral infections. Other triggers can include irritants, allergens, and exercise.

Due to the challenges in performing reliable spirometry on children under 6, asthma diagnosis in this age group relies on physical examination findings and the child’s response to medication as objective evidence of reversible airflow obstruction. Spirometry can be used to confirm the diagnosis once the child reaches 6 years of age.

Spirometry for Asthma Diagnosis (Age 6 and Over)

Spirometry is a pulmonary function test used to assess an individual’s lung function. It plays a crucial role in establishing an asthma diagnosis, monitoring disease progression, and evaluating the effectiveness of therapeutic interventions.10

Spirometry results are most accurate when the patient is symptomatic. Consider the patient’s medical history, including any recent hospitalizations, when interpreting spirometry results.

For caregivers and children who may have questions about what to expect during a spirometry appointment, Appendix A: Getting Ready for Spirometry provides helpful information.

Office Spirometry**

For spirometry to be eligible for coverage under the Medical Services Plan, testing must be conducted at an accredited facility. However, evidence indicates that with proper training and equipment, spirometry performed in a family physician’s office can be as reliable as testing in a pulmonary function laboratory for adult patients.12

Second-Line Tests for Asthma Diagnosis

When spirometry results are negative but clinical suspicion of asthma remains high, the following tests can be valuable in further evaluating for asthma:

Methacholine Challenge Test (MCC) (Age 8 and Over)

If spirometry is normal and asthma is still suspected, a methacholine challenge test (MCC) or an exercise challenge can be performed.7 MCC is particularly useful in ruling out an asthma diagnosis in symptomatic patients.13 It should be considered if a patient is not responding as expected to standard asthma therapy (see Indications for Referral).

This test is time-consuming and requires the child to perform spirometry consistently, making it generally unsuitable for children under 8 years of age.

Peak Flow Monitoring (PFM)

Peak flow monitoring (PFM) can be useful in providing objective evidence of variable airflow obstruction in situations where:

• Rapid evidence is required and spirometry is not readily available (e.g., due to geographical or accessibility issues).
• Work-related asthma is suspected, and PFM can be used to monitor peak flow at the workplace.
• A symptomatic patient has baseline peak flow readings for comparison (see Associated Document – Asthma Action Plan).

Spirometry is generally preferred over PFM because peak flow reference values are not as well-standardized, readings can be more variable, and peak flow meters are prone to malfunction.

When using PFM, it is important to ensure the same meter is used consistently, as readings can vary significantly between devices.

Other Diagnostic Tests: Allergy Testing

For patients whose asthma symptoms are not well controlled, particularly if symptoms are seasonal or triggered by specific inhaled allergens, identifying the allergens to which the patient is sensitized can be beneficial. Although allergy testing for inhaled allergens can be performed at any age, indoor allergens are more likely to cause symptoms after age 4, and outdoor allergens after age 5.14

Exposure to inhaled allergens has been shown to trigger asthma attacks in susceptible individuals. Food allergens are less commonly a cause of asthma symptoms unless the allergenic protein becomes aerosolized and inhaled, or in cases of anaphylaxis.9

Differential Diagnosis and Asthma Misdiagnosis

It’s important to note that up to 30% of patients diagnosed with asthma by a physician may be misdiagnosed.15,16,17 Spirometry is the recommended first-line diagnostic test to minimize misdiagnosis. In patients who do not respond well to asthma treatment, assuming medication adherence, correct inhaler technique, and management of comorbidities, reconsider the asthma diagnosis, correlate clinically, and obtain objective evidence of variable airflow obstruction.

Work-Related Asthma**

Work-related asthma encompasses both occupational asthma (asthma symptoms directly caused by workplace exposure to irritants or allergens) and work-aggravated asthma (pre-existing asthma symptoms that worsen due to workplace exposure).19

It is crucial to inquire about potential occupational exposures in all adult patients.15,20 Patients suspected of having work-related asthma should be referred to a specialist. WorkSafeBC provides additional information on this topic.

Asthma Management in Primary Care

The fundamental components of asthma management include:7

1. Assessing current asthma control and future exacerbation risk.
2. Providing comprehensive asthma self-management education, including a personalized written asthma action plan.
3. Identifying and addressing asthma triggers, including discussions about environmental control strategies when applicable.
4. Prescribing appropriate pharmacological treatment to achieve and sustain asthma control.

1. Asthma Control and Risk Assessment

Once an asthma diagnosis is confirmed (or highly probable):

• Evaluate the patient’s current level of asthma symptom control.
• Assess the patient’s risk of future asthma exacerbations.9
• Develop or modify the patient’s asthma treatment plan – see Table 6: Assessing asthma symptom control.

A patient with well-controlled asthma will exhibit none of the symptoms listed in the poorly controlled column of Table 6.7

A patient is considered at higher risk for asthma exacerbations if they have any of the following risk factors:

• History of previous severe asthma exacerbation (requiring systemic steroids, emergency department visit, or hospitalization).
• Poorly controlled asthma symptoms.
• Overuse of short-acting beta-agonists (SABAs), indicated by filling more than 2 SABA inhaler prescriptions in the past year.
• Current smoker.

Asthma Severity Classification

Asthma severity can only be accurately assessed retrospectively, after a patient has achieved well-controlled asthma for a minimum of 3 months.9 Severe asthma is relatively uncommon, affecting approximately 3.7% of the total asthma population.9 Poorly controlled asthma is more frequently due to factors such as poor adherence to daily medication or incorrect inhaler technique.

The classification of asthma severity has evolved, and the terms “persistent” and “intermittent” are no longer used, as asthma is recognized as a chronic condition, even if symptoms are intermittent. Severity classifications range from very mild to severe:7

• Very Mild Asthma: Patient is well-controlled with as-needed (PRN) SABA use only.
• Mild Asthma: Patient is well-controlled on low-dose inhaled corticosteroid (ICS) (or leukotriene receptor antagonist – LTRA) and PRN SABA, or PRN budesonide/formoterol.
• Moderate Asthma: Patient is well-controlled on low-dose ICS plus a second controller medication and PRN SABA, or moderate-dose ICS +/- a second controller medication and PRN SABA, or low-to-moderate dose budesonide/formoterol plus PRN budesonide/formoterol.
• Severe Asthma: Requires high doses of ICS plus a second controller for the past year or systemic steroids for 50% of the previous year to maintain control, or remains uncontrolled despite this level of therapy.

2. Asthma Self-Management Education and Written Action Plans

Begin by assessing the patient’s existing knowledge about asthma. Then, discuss:

• The nature of asthma as a chronic condition and the mechanisms of asthma attacks.
• Treatment goals, including defining well-controlled asthma and understanding the patient’s or caregiver’s perception of quality of life.
• Treatment options, taking into account the patient’s or caregiver’s willingness to use pharmacological therapy, as well as trigger identification and potential lifestyle or environmental modifications. See Appendix B: Supporting Patients with Poor Medication Adherence for strategies to address medication adherence.

Following this discussion, develop a written asthma action plan collaboratively with the patient and/or caregiver(s) (refer to Asthma Action Plan). Refer the patient to an asthma education program if available in your area. Online resources, such as the Provincial Health Services Authority’s (PHSA) Guide for Families and Caregivers video, can also be valuable tools. See Physician and Patient Resources for additional resources.

Supporting Patients with Poor Asthma Control

When addressing poorly controlled asthma, approach the topic with sensitivity. Patients or caregivers may be hesitant to disclose factors contributing to poor control, such as cost concerns, forgetfulness, or physical limitations (e.g., arthritis) that affect medication adherence or treatment plan implementation.

For more information on identifying and supporting patients struggling with medication adherence, consult Appendix B: Supporting Patients with Poor Medication Adherence.

3. Identifying Asthma Triggers and Environmental Control

Identify environmental factors that trigger a patient’s asthma through detailed history taking. When possible, advise patients to avoid these triggers. For adult patients, consider workplace environmental factors.

Smoking Cessation and Asthma

Active Smoking

Active smoking significantly increases the risk of poor asthma control, hospitalizations, accelerated decline in lung function, and reduces the effectiveness of both inhaled and oral corticosteroids.9 Encourage smokers to quit smoking at every visit. Connect smoking cessation to the patient’s personal health goals. Refer to the Resources section of this guideline and the BC Guidelines: Tobacco Cessation for smoking cessation support.

Passive Smoke Exposure

Exposure to passive smoke also elevates the risk of poor asthma control and can contribute to hospitalizations. Advise parents and caregivers of children with asthma to abstain from smoking. If quitting is not immediately possible, strongly advise them not to smoke around their children, or in vehicles or rooms where children are present.

Wildfire Smoke and Asthma

Wildfire smoke exposure is a significant concern, particularly in regions like BC, where wildfire frequency and intensity have increased in recent years.22 Exposure to wildfire smoke and debris is associated with increased physician visits, emergency room visits, hospitalizations, respiratory infections, and overall mortality.23–28

Wildfire smoke exposure is also linked to increased dispensing of rescue inhalers,24 a marker of worsening asthma control.

Wildfire Smoke and Children with Asthma

Exposure to wildfire smoke and ash poses a particularly high risk to children because their lungs are still developing.29

Strategies to Minimize Wildfire Smoke Exposure

During wildfire events, patients with asthma can minimize their risk of exacerbation by implementing the following measures:30–31

• Stay informed about local air quality reports (see Air Quality and Wildfire Resources for resources).
• Keep doors, windows, and fireplace dampers closed.
• Use portable air cleaners with HEPA filters in one or more rooms.
• Utilize air conditioners on the recirculation setting to prevent outdoor air from entering.
• Avoid outdoor exercise.

Environmental Control Interventions

Evidence supporting the effectiveness of environmental control interventions for asthma is limited.13 However, combining two or more single-component interventions is generally more effective than a single intervention alone.13 Environmental interventions may include:

• Using HEPA filters in air purifiers and vacuum cleaners.
• Avoiding strong cleaning products and fragrances.
• Implementing pest and rodent control measures.
• Removing carpets, if feasible.
• Minimizing pet allergen exposure, for example, by restricting pets to specific areas of the home.

4. Pharmacological Treatment for Asthma

Asthma medications are generally classified into three categories:

• Controller Medications: These are used daily to reduce airway inflammation, control symptoms, and reduce the risk of future exacerbations. Consistent daily use is essential for controller medications to be effective.
• Reliever Medications: These are used as needed to treat breakthrough asthma symptoms.
• Biologic Therapies for Severe Asthma: These advanced medications are prescribed by asthma specialists for patients with severe, uncontrolled asthma. See Biologics below for more information.

Selection of Inhaler Device

The most critical factor in choosing a medication delivery device is ensuring the patient can use it correctly and consistently.

Pressurized Metered Dose Inhalers (MDIs)

Pressurized metered-dose inhalers (MDIs) consist of a pressurized canister in a plastic holder with a mouthpiece. MDIs use a propellant, hydrofluoroalkane (HFA), to deliver medication. HFAs are potent greenhouse gases with a high global warming potential.19 MDIs contribute significantly to the healthcare sector’s carbon footprint.32

In British Columbia, over 1.7 million inhalers are dispensed annually. In 2021, this contributed approximately 22,000 tonnes of CO2e, equivalent to driving a standard gasoline-powered vehicle 86 million kilometers. Virtually all of these greenhouse gas emissions are attributable to MDIs, even though MDIs constitute only 6 out of 10 inhalers dispensed in BC.47

When an MDI is the most appropriate treatment option clinically, consider prescribing a low-volume HFA inhaler over a high-volume HFA inhaler.19 Notably, one brand of salbutamol inhaler generates the same carbon emissions per inhaler as driving a car 113 km, while another brand of the same medication, with identical coverage, generates emissions equivalent to driving a car 38.8 km per inhaler (see Figure 1).32

The leaf icon in Appendix C: Asthma Medication Table indicates medication options with a lower environmental impact. For detailed information on the environmental impact of specific medications, refer to the Inhaler Coverage and Environmental Impact Guide.

Spacer Devices for MDIs

Spacer devices (valved holding chambers) must be purchased separately. However, spacers significantly improve MDI technique and enhance medication delivery to the lungs. Spacers are recommended for patients of all ages prescribed an MDI, particularly when using inhaled corticosteroids.

Dry Powder Inhalers (DPIs)

Dry powder inhalers (DPIs) rely on the patient’s inspiratory effort to aerosolize and inhale the medication, eliminating the need for propellants. This makes DPIs a more environmentally friendly option. DPIs are contraindicated for young children or adult patients with conditions such as neuromuscular weakness or frailty who may not generate sufficient inspiratory flow.

Propellant-free devices also offer benefits in other environmental spheres.33 Accurate asthma diagnosis is crucial to avoid unnecessary medication prescriptions, including inhaler devices and pharmaceutical chemicals.33

Nebulizers are no longer routinely recommended for asthma management in any age group. MDIs with spacers are as effective as nebulizers34 and pose a lower infection risk.

Stepwise Asthma Management Approach

Initiate treatment at the step most appropriate for the patient’s initial asthma severity. If symptom control is inadequate (see Table 6. Assessing asthma symptom control), investigate the reasons for poor control before escalating therapy to the next step. This assessment should include:

• Medication adherence.
• Inhaler technique (including confirming they are not using an empty inhaler).
• Environmental exposures.
• Co-existing conditions (comorbidities) such as rhinosinusitis or GERD, which can worsen or mimic asthma symptoms.

If asthma control is maintained and exacerbation risks are well-managed for at least 3 months, consider stepping down therapy to the previous step. Ensure the patient has been exacerbation-free for the past year before reducing treatment.

Asthma Management During Pregnancy

Pregnant patients should continue their asthma medications throughout pregnancy.

• Medication Safety: Most asthma medications are considered safe during pregnancy. Budesonide is generally considered the safest inhaled corticosteroid for pregnant women.35 The risks associated with untreated asthma during pregnancy far outweigh any potential risks from asthma medications.36
• Asthma Action Plan: A pregnant patient’s asthma action plan should include instructions to contact their obstetrical care provider during exacerbations to ensure fetal well-being is monitored. Consider involving both an obstetrical care provider and an asthma specialist in the care team.
• Monthly Asthma Assessment: Approximately one-third of pregnant women with asthma may experience worsening symptoms during pregnancy and benefit from closer (monthly) monitoring.37

Pregnant patients with uncontrolled or severe asthma should be managed in consultation with a specialist.

Biologics and Add-on Therapies for Severe Asthma

Biologic therapies for asthma are reserved for patients with severe asthma and should be prescribed by asthma specialists after confirming:

• The patient requires high-dose inhaled steroids, and
• A second controller medication to achieve asthma control (or asthma remains uncontrolled despite these medications).38

For patients to be eligible for PharmaCare coverage of asthma biologics, evidence of good adherence to asthma controller medications (assessed through prescription refill data in PharmaNet) is required. Therefore, it is prudent to ensure patients are consistently filling their controller medication prescriptions before referral to a specialist.

Managing Asthma Exacerbations – The Yellow Zone

Increased asthma symptoms typically place individuals in the “yellow zone” of their asthma action plan (see Associated Documents: Asthma Action Plans). The yellow zone serves as a symptom-based warning sign indicating an increased risk of exacerbation and the need to adjust medication.

Symptoms indicative of the yellow zone are detailed in Table 9 below. Early recognition of the yellow zone and prompt intervention are essential for effectively stabilizing asthma and preventing severe exacerbations.1

Patients experiencing “Mild to Severe” symptoms (as defined in their action plan) should follow their asthma action plan and/or schedule an urgent appointment with their healthcare provider. An asthma exacerbation may be imminent, and timely intervention can prevent it from worsening. Patients experiencing symptoms of a life-threatening asthma exacerbation should seek immediate emergency medical attention.

Yellow Zone Asthma Exacerbation Management

For adults who have experienced an exacerbation within the past year, a trial of a 4- to 5-fold increase in their maintenance ICS dose for 7-14 days may be considered.7 Important Note: This dosage exceeds product monograph limits for total daily dose and is not intended for chronic daily use. While short-term dose increases beyond these limits are unlikely to pose significant safety risks, formal safety testing data are not available, and the decision to adopt this approach should be based on clinical judgment and patient comfort. Prescribers should be aware of the maximum approved doses of ICS and LABA in Canada (see Appendix C: Asthma Medication Table).

It’s crucial to remember that even as few as four short courses of systemic steroids in a lifetime can be associated with significant adverse events. Requiring a course of systemic steroids should prompt a thorough re-evaluation of the patient’s asthma management plan.46

Ongoing Asthma Care

Regular office visits are essential for ongoing asthma management. During these visits, review the following with the patient:*

1. Medication adherence.
2. Inhaler technique (ask the patient to demonstrate their inhaler technique).
3. Symptom monitoring practices.
4. Level of asthma symptom control and ability to adhere to lifestyle modifications.
5. Asthma action plan (revise and update as needed).

Follow-up After a Severe Asthma Exacerbation

Schedule follow-up visits within 2-4 weeks after any severe exacerbation that required an emergency room visit, hospitalization, or systemic steroid use. At this visit, assess:

1. Modifiable risk factors that contributed to the exacerbation (e.g., medication adherence, inhaler technique).
2. Whether the patient correctly used their asthma action plan during the exacerbation.
3. Whether any modifications to the asthma action plan are needed.

Patients with risk factors for near-fatal asthma attacks (see Table 10. Risk factors associated with near-fatal asthma below) require particularly close and diligent follow-up. Refer to the Resources section of this guideline for additional support materials.

Reassessing Asthma Symptom Persistence in Children

Approximately 50% of preschool-aged children who experience wheezing will outgrow their asthma by the age of 6.40 Therefore, the ongoing need for asthma therapy in children should be reassessed periodically.

A trial off controller medication can be considered for children who have been well-controlled (with no exacerbations) while exposed to their typical asthma triggers for the past 6 to 12 months.7 Close monitoring is essential during this trial period.

Influenza and COVID-19 and Asthma

Influenza and COVID-19 are known triggers for acute asthma exacerbations.9 Vaccination against these viruses reduces the risk of infection and subsequent asthma exacerbations. Encourage patients to maintain their recommended influenza and COVID-19 vaccinations.

Mask-wearing is an effective measure to reduce the spread of viral illnesses and is not a risk factor for asthma exacerbations.41

Indications for Asthma Specialist Referral

Referral to an asthma specialist is recommended in the following situations:

• Atypical asthma symptoms or diagnostic uncertainty.
• Poorly controlled asthma or frequent asthma exacerbations despite optimal asthma control strategies (poor lung function, persistent asthma symptoms) and good adherence to Step 3 or 4 treatment (see Stepwise approach).
• Frequent asthma exacerbations despite moderate doses of inhaled corticosteroids (with confirmed proper inhaler technique and good adherence).
• Need for allergy testing to assess the potential role of environmental allergens in patients with a suggestive clinical history.
• Suspected occupational asthma.
• Pregnancy in a patient with severe asthma.
• Any asthma-related hospitalization, ³ 2 emergency department visits, or ³ 2 courses of systemic steroids in a year.
• History of a life-threatening asthma event, such as ICU admission for asthma.

Environmental Impact and Climate Change in Asthma Management

Climate Change and Asthma

While asthma exacerbations can occur throughout the year, seasonal patterns are often observed.42

In children, asthma exacerbation rates are typically highest in the fall. The “September Epidemic” is attributed to an increase in rhinovirus respiratory infections among children when they return to school, along with contributing environmental factors such as pollen, temperature changes, and air pollutants.

Climate change is impacting the seasonal asthma cycle in several ways:

• Prolonged Pollen Seasons: Warmer temperatures lead to longer pollen seasons, increasing allergen exposure for a more extended period.
• Increased Air Pollution: Climate change contributes to increased ground-level ozone and particulate matter, both of which are respiratory irritants and asthma triggers.

Other climate events, such as heatwaves44 and flooding43, can also pose exacerbation risks for patients with asthma. Consider these climate-related factors when developing individual Asthma Action Plans.

Controversies in Asthma Care

Use of Short-acting Beta-agonists (SABAs) Alone for Very Mild Asthma

Some asthma guidelines recommend against prescribing SABAs as monotherapy for any patient with asthma, citing evidence for the benefits of inhaled corticosteroids in reducing exacerbations, even in mild asthma. Other guidelines consider PRN SABA use an acceptable option for patients with very mild asthma (see Asthma severity) who are at low risk of exacerbations (see Assessing control and risk).

Preference for Daily Inhaled Corticosteroids (ICS) for Mild Asthma

Some guidelines advocate for PRN ICS-formoterol regimens for adults with mild asthma, acknowledging that patient adherence to daily medication can be challenging. Other guidelines recommend daily ICS as first-line therapy for mild asthma due to better asthma control and improved lung function. PRN ICS-formoterol regimens are then reserved as a first-line option primarily for patients aged 12 and older with documented poor adherence to daily medication despite adequate asthma education and support.

Physical Activity, Diet, and Breathing Exercises in Asthma

While evidence supporting the direct therapeutic benefit of physical activity, healthy diet, and breathing exercises in mitigating asthma is inconclusive, there is fair evidence that these practices improve overall quality of life for people with asthma.9

Wait Times and Accessibility of Spirometry

Wait times for spirometry and the geographical accessibility of testing facilities vary across regions. In some areas, the distance to a spirometry facility may be prohibitive, or the time between referral and the procedure may exceed recommended testing intervals.

Asthma-COPD Overlap Syndrome (ACOS)

Asthma-COPD Overlap Syndrome (ACOS) was discussed in previous guidelines. However, despite some shared characteristics between asthma and COPD, ACOS lacks a clear and universally accepted definition.45

Therefore, practitioners are generally discouraged from diagnosing patients with ACOS.

Resources for Asthma Diagnosis and Management

References

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31 Forest Fires and Lung Health [Internet]. Canadian Lung Association; Available from: https://www.lung.ca/lung-health/forest-fires-and-lung-health

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Abbreviations:

FABA Fast-acting beta agonist

LABA Long-acting beta agonist

SABA Short-acting beta agonist

Bud/form A single inhaler containing both budesonide and formoterol

PRN “Pro re neta”, or “as needed”

ICS Inhaled corticosteroid

HFA Hydrofluoroalkane

LTRA Leukotriene receptor antagonist

MDI Metered dose inhaler

DPI Dry powder inhaler

Practitioner Resources

Emergency Management and Planning:

Patient, Family and Caregiver Resources

Air Quality and Wildfire Resources

Diagnostic code: 493 (Asthma)

Appendices

Associated Documents

The following documents accompany this guideline:

List of Contributors

List of Contributors (PDF, 33KB)

This guideline is based on scientific evidence current as of the Effective Date.

This guideline was developed by the Guidelines and Protocols Advisory Committee, approved by the British Columbia Medical Association, and adopted by the Medical Services Commission.

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The principles of the Guidelines and Protocols Advisory Committee are to: – encourage appropriate responses to common medical situations – recommend actions that are sufficient and efficient, neither excessive nor deficient – permit exceptions when justified by clinical circumstances. #### Contact Information Guidelines and Protocols Advisory Committee PO Box 9642 STN PROV GOVT Victoria BC V8W 9P1 E-mail: [email protected] Web site: www.BCGuidelines.ca |

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Disclaimer

The Clinical Practice Guidelines (the “Guidelines”) have been developed by the Guidelines and Protocols Advisory Committee on behalf of the Medical Services Commission. The Guidelines are intended to give an understanding of a clinical problem, and outline one or more preferred approaches to the investigation and management of the problem. The Guidelines are not intended as a substitute for the advice or professional judgment of a health care professional, nor are they intended to be the only approach to the management of clinical problem. We cannot respond to patients or patient advocates requesting advice on issues related to medical conditions. If you need medical advice, please contact a health care professional.