Asthma is a chronic inflammatory disease that causes the airways to swell and narrow, resulting in difficulty breathing. This condition involves episodes of wheezing, breathlessness, chest tightness, and coughing that vary in frequency and intensity. Healthcare providers classify asthma into different levels of severity to effectively manage this variability. These classifications help determine the appropriate starting point for treatment, and this article focuses on Moderate Persistent Asthma (MPA).
Understanding the Asthma Severity Scale
The severity of asthma is categorized using guidelines established by the National Asthma Education and Prevention Program (NAEPP), which utilizes a stepwise approach to classification. This system helps clinicians match the intensity of the disease with the necessary level of medication to achieve control. Classification is typically based on two main components: the frequency and intensity of symptoms, and objective lung function measurements taken before a patient starts long-term control therapy.
The NAEPP divides asthma into four distinct classifications: Intermittent, Mild Persistent, Moderate Persistent, and Severe Persistent. Intermittent is the least severe, and Severe Persistent is the most intense. A patient’s classification is determined by the most severe feature they exhibit, meaning a single factor can place them into a higher category. For instance, a patient may have mild daytime symptoms but severe lung function compromise, classifying them based on the lung function component. The classification is used to guide the initial step of the treatment plan, which is then adjusted over time to maintain optimal control.
Key Symptom Indicators of Moderate Persistent Asthma
The diagnosis of Moderate Persistent Asthma relies heavily on a patient’s reported symptoms and their impact on daily life. Individuals with this level typically experience symptoms like coughing, wheezing, or shortness of breath every day. These daily symptoms, or flare-ups, often last for several days and can noticeably affect normal physical activity, leading to some limitation.
A significant indicator of this severity level is the daily need to use a Short-Acting Beta-Agonist (SABA), commonly known as a rescue inhaler, for symptom relief. Needing the SABA every day signals that the underlying airway inflammation is not adequately controlled. Nighttime awakenings due to asthma symptoms are also more frequent than in milder forms, typically occurring more than once per week. Specifically, this may be defined as five or more times per month.
Objective Measures Used for Diagnosis
Beyond the patient’s subjective experience, the diagnosis of Moderate Persistent Asthma is confirmed through objective medical testing, primarily using Pulmonary Function Tests (PFTs). These tests measure how well the lungs are working and provide data that correlates with symptom severity. The most commonly used measurement is the Forced Expiratory Volume in 1 second (FEV1), which represents the volume of air a person can forcefully exhale in the first second of a full breath.
For a diagnosis of Moderate Persistent Asthma in adults and children over 12, the FEV1 is typically found to be between 60% and 80% of the predicted value. This finding reflects a measurable and consistent obstruction of the airways. Another measure is the variability in Peak Expiratory Flow (PEF) rate, which is the maximum speed of exhalation. A variability greater than 30% between morning and evening readings is also a marker for this severity level.
Standardized Treatment for Moderate Persistent Asthma
The standardized management for Moderate Persistent Asthma is generally aligned with Step 3 or Step 4 of the NAEPP’s stepwise treatment guidelines. Since the disease is persistent, meaning symptoms occur daily, the foundation of treatment involves daily long-term control medications. The preferred treatment strategy for this severity level is combination therapy, which typically pairs an Inhaled Corticosteroid (ICS) with a Long-Acting Beta-Agonist (LABA).
The ICS component addresses the underlying chronic inflammation in the airways, while the LABA provides prolonged bronchodilation to keep the airways open. This combination is often delivered in a single inhaler to simplify the regimen and improve adherence, using a low-to-medium dose of the ICS. Patients must also maintain access to a SABA rescue inhaler for acute flare-ups, but daily use of the rescue inhaler signifies that the long-term controller medication needs to be adjusted. Furthermore, a written Asthma Action Plan is provided to guide the patient on how to adjust medications based on changes in symptoms or peak flow readings.