Update on Asthma Management Guidelines

Abstract

The Global Initiative for Asthma (GINA) was established in 1993 and publishes a yearly global strategy to improve asthma awareness, prevention and management of asthma worldwide, based on a review of the most updated evidence. The current 2024 GINA update advises that all adults and adolescents with asthma receive inhaled corticosteroid (ICS)- containing medication and should not be treated with short acting beta agonist (SABA) alone. The 2024 GINA strategy divides treatment into two ‘Tracks”: Track 1 (preferred Track), the reliever is as-needed combination low dose ICS-formoterol; Track 2 uses SABA as the reliever along with a separate ICS inhaler. The updates also stress the importance that individuals with asthma should have a written asthma action plan, and asthma management should be tailored to the individual to help reduce the occurrence of serious exacerbations, fatalities, and hospitalizations.

Introduction

Asthma is the most prevalent chronic non-communicable condition impacting over 260 million individuals globally. In the United States, asthma prevalence is 7.9% with higher prevalence among individuals residing in areas with lower annual household incomes. According to the Global Burden of Disease report, asthma contributes to 42,000 deaths annually worldwide.¹ Avoidable factors, such as under-prescription of inhaled glucocorticoids or inadequate access to medical care, contributes to the majority of asthma-related deaths. This overview delves into the goals and components of asthma management, applicable to adult populations and reviews the Global Initiative for Asthma (GINA) 2024 guidelines.

According to GINA, asthma is defined as a heterogeneous disease characterized by chronic airway inflammation. Patients have recurrent respiratory symptoms including shortness of breath, wheezing, chest tightness, coughing, and fatigue which limits expiratory airflow. Spirometry with before and after bronchodilator administration, peak expiratory flow (PEF) measurement, and flow-volume loop helps further assist in asthma diagnosis and management. A scooped, concave shape of the expiratory segment of the flow-volume loop indicates intrathoracic airflow obstruction, a characteristic feature of asthma and other obstructive lung conditions. Normal pulmonary function tests can be seen in patients with asthma, especially when patients is otherwise asymptomatic. However, some asthma patients experience persistent airflow limitation regardless of symptomatology, often associated with long-standing, poorly controlled disease.

After diagnosis, there are two primary goals of treatment. Symptom control focuses on reducing symptoms, limiting sleep disturbance, and minimizing limitations in daily life. Risk reduction focuses on maintaining normal lung function, preventing exacerbations or death, and minimizing medication side effects. Asthma Control Test (ACT) is a standard assessment that evaluates the effectiveness of current asthma management (Figure 1). If inadequately controlled, treatment should be escalated through a “step up” therapy. Well controlled asthma patients experience symptoms requiring quick-reliever medication on less than two days/week, nighttime awakenings less than two nights/month, maintain lung function or forced expiratory volume in 1 second (FEV1) within normal range (or 20% of personal best value), and encounter no more than one exacerbation/year necessitating urgent care or oral glucocorticoids.

Figure 1.

Asthma Control Test

Regular utilization of SABA, even for a duration as short as one to two weeks, can lead to detrimental effects such as beta-receptor downregulation, diminished broncho-protection, and rebound hyper-responsiveness. Increased SABA usage correlates with adverse clinical outcomes; dispensing three or more SABA inhalers, annually is linked with a heightened risk of exacerbations, while dispensing twelve or more SABA inhalers annually significantly elevates the risk of mortality.

Tract 1

For this reason, studies that looked at as-needed-only low dose ICS-formoterol compared with the former “standard” as-needed SABA only treatment. Two studies showed the risk of severe exacerbations was reduced by 60–64% in those that used as-needed ICS-formoterol in Steps 1–2 of the Track 1 of GINA Guidelines versus as-needed SABA (Figure 2).^{2, 3} GINA now advises that all adults and adolescents with asthma should have access to ICS-containing inhalers (e.g., budesonide-formoterol 80 mcg-4.5 mcg or 160 mcg-4.5 mcg), administering one to two inhalations as needed for asthma symptoms to diminish the occurrence of serious exacerbations, fatalities, hospitalizations, and exacerbations necessitating oral steroid treatment.^{4, 5}

Figure 2.

Steps in GINA Guidelines

The step-up therapy outlined in the GINA guidelines involves gradual increase in medication dosage or type to achieve better asthma control (Figure 1).⁴ If asthma symptoms persist, therapy is escalated by transitioning to low-dose maintenance ICS-formoterol (Step 3), then gradually progressing to medium-dose maintenance ICS-formoterol (Step 4). Steps 3–5 include Single Maintenance and Reliever Therapy (SMART), with ICS-formoterol used as both a maintenance and reliever inhaler help to reduce severe exacerbations compared with ICS or ICS-LABA plus SABA reliever.⁴ If symptoms persistent to Stage 5, additional long-acting muscarinic antagonist (LAMA) and biologic agents may be introduced. The primary aim is to attain and sustain asthma control using the minimal necessary medication.^{4, 5}

Track 2

An alternative approach, Track 2 (Figure 2), involves taking an ICS containing medication whenever short-acting beta-agonist (SABA) is used, and gradually escalating to low-dose maintenance ICS (Step 2).⁴ The BEST study looked at 445 patients over six months, and showed the mean number of exacerbations per patient per year was lower in the combined ICS-SABA group compared to as needed SABA alone.⁶ Most recently, in the study Albuterol-Budesonide Fixed Dose Combination Rescue Inhaler for Asthma, the hazard ratio for probability of severe exacerbations was 0.73 (95% CI 0.61–0.88) with higher-dose of as-needed albuterol-budesonide compared with as-needed albuterol alone.⁷ The evidence continues to point to access to an ICS containing inhaler for rescue, whether that be in the ICS-LABA formulation or ICS-SABA or ICS plus SABA.^{4, 5} Steps 3–5 of Track 2 follow Track 1 with regards to the up titration of controller medications and eventual addition of biologic agents.⁴

Conclusion

SMART (Single Inhaler Maintenance and Reliever Therapy) for asthma offers the advantage of simplifying the treatment regimen by using a single inhaler for both maintenance and reliever medication, which may improve adherence and provide quick symptom relief. However, it carries the risk of overuse of the reliever component, limited availability of suitable combination inhalers, and potential for confusion in medication use, and may not be suitable for all patients.

Most insurance companies only allow for one ICS-LABA inhaler per month, which may be problematic for patients using this as SMART therapy.

Patients with frequent symptoms run the risk of running out of their ICS-LABA inhaler early in the month resulting in no maintenance and reliever therapy available until the following month. Patients with intermittent or mild persistent asthma using their ICS-LABA as needed less than 120 inhalations per month are good candidates for SMART therapy. Patients with moderate or severe asthma have an increased risk of running out of their ICS-LABA inhaler and should generally use their ICS-LABA twice daily with rescue use of albuterol or the recently approved albuterol-budesonide inhaler.

Regardless of the Track used, patients require a tailored “asthma action plan,” or a documented guide that furnishes them with instructions to adhere to at home (Figure 3). This aids in clarifying medication schedules, assisting patients in recognizing deteriorations in asthma control, and directing treatment modifications based on alterations in symptoms, as well as home measurements of peak expiratory flow (PEF). It should undergo review and refinement during subsequent follow-up appointments. Highlighting the patient’s individual goals is crucial for improving adherence.

Figure 3.

Asthma Action Plan

Asthma management should be focused on maximizing symptom control and mitigating likelihood of flare ups while reducing the adverse effects of medications. Well-managed asthma allows individuals to lead active lives and it involves educating patients, reducing exposure to triggers, monitoring symptoms and lung function, and administering appropriate treatments. GINA 2024 guidelines emphasize the importance of switching from single SABA use to early ICS-formoterol (or ICS plus SABA) use for the reliever medication to prevent exacerbations and diminish the occurrence of serious exacerbations, fatalities, hospitalizations, and exacerbations necessitating oral steroid treatment. Optimal asthma management requires a multifaceted approach, addressing clinical, social, and environmental factors to improve outcomes and enhance quality of life.