BACKGROUND: African Americans experience higher death rates from asthma than whites. Understanding potential differences in how these 2 ethnic groups describe or experience their symptoms during an asthma exacerbation may improve asthma management in African Americans.
POPULATION STUDIED: The investigators studied 40 adult asthmatics with atopy whose baseline asthma therapy consisted of only intermittent b-agonists. Patients were excluded if they used inhaled or oral steroids, theophylline, or antihistamines within 6 weeks of the study. Also, patients were not enrolled if they had hypertension, heart disease, diabetes, malignancy, or immune disorders or if they had used tobacco within the past year or had a cumulative history greater than 10 pack-years. Eight patients were dropped because sufficient airflow obstruction could not be induced; 6 of those were African American. Of the resultant African American group 75% were women, but only 56% of the whites were women.
STUDY DESIGN AND VALIDITY: This study was an experimental protocol, artificially inducing bronchocontriction in otherwise asymptomatic asthmatics. Subjects were given methacholine to induce bronchoconstriction, resulting in a 30% drop in forced expiratory volume in 1 second (FEV1). Two minutes after dosing, subjects described the sensations they experienced in their own words. The descriptions were clustered into general groups for those descriptors used by at least 75% of the group participants. Subjects also rated the severity of breathlessness by visual analog scale (VAS) and by selecting word or number descriptors. This experimental study was tightly controlled to be able to accurately match the symptoms in the 2 ethnic groups. However, this design may not reflect the more complicated and variable patients seen in everyday practice. Also, the study was performed in one geographic area (northern California), and patients in other areas may use a different vocabulary to express their symptoms. Similarly, induced bronchoconstriction may be experienced differently than a natural occurring asthma attack. Also, our ability to generalize the results is frequently limited in qualitative studies such as this one.
OUTCOMES MEASURED: The categories of phrases used to describe the sensation of breathlessness comprised the primary outcome. Symptom severity was a secondary outcome.
RESULTS: Words used to describe the symptoms during airflow obstruction differed between the 2 ethnic groups. African Americans were statistically more likely to use upper airway descriptors to explain their breathlessness: “tight throat,” “voice tight,” “itchy throat,” “tough breath,” and “scared-agitated” were the word clusters most often used. Whites were more apt to use lower airway terms, such as “deep breath,” “out of air,” “aware of breathing,” “hurts to breathe,” and “lightheaded.” No subjects used the traditional medical terminology of “shortness of breath” or “wheezing.” African American subjects rated their baseline breathlessness slightly greater than whites (14.25 vs 11.0 on a 0-100 VAS, P <.04). As expected, severity scores increased as FEV1 decreased. At a 20% reduction, whites reported a greater sense of breathlessness, but there was no difference between the 2 groups at a 30% reduction in FEV1.
This study alerts clinicians to the possibility that African American asthmatics may be more likely to use upper airway terms to describe their airflow obstructive symptoms. This descriptive study does not demonstrate any differences in patient-oriented outcomes. However, the potential harm of missing an asthma exacerbation warrants the small additional effort of clinicians to pursue bronchospasm as a possible etiology in asthmatics presenting with upper airway symptoms.