Disease Burden of Mild Asthma: Findings from a Cross-Sectional Real-World Survey

INTRODUCTION: Most asthma patients have mild disease, although the burden of mild asthma is not well understood nor studied. Some evidence suggests that many patients with mild asthma experience suboptimal symptom control and exacerbations. This study characterizes the burden of illness and treatment patterns among patients with a confirmed diagnosis of mild asthma, defined as GINA Step 1 or Step 2, and residing in China, France, Germany, Italy, Japan, Spain, the United Kingdom, or the United States. METHODS: The Respiratory Disease-Specific Programme prospective cross-sectional survey was conducted with primary care and specialty physicians in each of the eight countries. Physician and patient surveys assessed demographic and clinical characteristics, frequency and timing of asthma symptoms, exacerbations, and rescue inhaler usage, the most recent FEV(1)% predicted, and healthcare utilization. GINA Step was determined by prescribed treatment regimen. GINA Step 1 patients were prescribed as-needed reliever medication and Step 2 required treatment with a low-dose inhaled corticosteroid, leukotriene receptor antagonist, or theophylline. Treatment adherence was assessed with the Morisky Medication Adherence scale, disease control with the Asthma Control Test, and work and activity impairments with the Work Productivity and Activity Impairment scale. RESULTS: The sample included 1115 GINA Step 1 and 2 patients, with 53% classified as Step 2. Overall asthma control was suboptimal, with reports of nocturnal symptoms (40.6%), symptom worsening (10.5%), and rescue inhaler usage in the last 4 weeks (33.6%). 25% of patients were uncontrolled. The overall mean number of exacerbations in the last 12 months was 0.4, with a higher frequency of exacerbations in Step 2 patients who also experienced more exacerbations requiring treatment intensification, an emergency department visit, or hospitalization. CONCLUSION: Mild asthma imposes a substantial burden on patients, establishing the need for comprehensive management plans and ongoing support for treatment adherence. FUNDING: AstraZeneca.