Definition, Categorization, and Terminology of Episodic Breathlessness: Consensus by an International Delphi Survey

Abstract

ContextEpisodic breathlessness is a common and distressing symptom in patients with advanced disease. Still, it is not yet clearly defined. ObjectivesThe aim of this work was to develop an international definition, categorization, and terminology of episodic breathlessness. MethodsAn online Delphi survey was conducted with international breathlessness experts. We used a structured questionnaire to identify specific aspects and reach agreement on a definition, categorization, and terminology (five-point Likert scale). Consensus was defined in advance as ≥70% agreement. ResultsThirty-one of 68 (45.6%), 29 of 67 (43.3%), and 33 of 67 (49.3%) experts responded in the first, second, and third rounds, respectively. Participants were 20–79 years old, about 60% male, and more than 75% rated their own breathlessness expertise as moderate to high. After three rounds, consensus was reached on a definition, categorization, and terminology (84.4%, 96.3%, and 92.9% agreement). The final definition includes general and qualitative aspects of the symptom, for example, time-limited severe worsening of intensity or unpleasantness of breathlessness in the patient's perception. Categories are predictable or unpredictable, depending on whether any triggers can be identified. ConclusionThere is high agreement on clinical and operational aspects of episodic breathlessness in advanced disease among international experts. The consented definition and categorization may serve as a catalyst for clinical and basic research to improve symptom control and patients' quality of life.