Background: Episodic dyspnea (ED) is a common problem in patients with advanced lung cancer (LC). However, the prevalence of ED and other related aspects in this patient population is not known. Objectives: To assess and describe the prevalence, clinical features, treatment, and risk factors for ED in outpatients with advanced LC. Design: Multicenter cross-sectional study. Subjects: Consecutive sample of adult outpatients with advanced LC. Measurements: We assessed background dyspnea (BD), the characteristics, triggers, and management of ED. Potential ED risk factors were assessed through multivariate logistic regression. Results: A total of 366 patients were surveyed. Overall, the prevalence of ED was 31.9% (90% in patients reporting BD). Patients reported a median of one episode per day (interquartile range [IQR]: 1-2), with a median intensity of 7/10 (IQR: 5-8.25). ED triggers were identified in 89.9% of patients. ED was significantly associated with chronic obstructive pulmonary disease (p = 0.011), pulmonary vascular disease (p = 0.003), cachexia (p = 0.002), and palliative care (p < 0.001). Continuous oxygen use was associated with higher risk of ED (odds ratio: 9.89; p < 0.001). Opioids were used by 44% patients with ED. Conclusions: ED is highly prevalent and severe in outpatients with advanced LC experiencing BD. The association between intrathoracic comorbidities and oxygen therapy points to alveolar oxygen exchange failure having a potential etiopathogenic role in ED in this population. Further studies are needed to better characterize ED in LC to better inform treatments and trial protocols.
Keywords: breathlessness; dyspnea; episodic dyspnea; lung cancer; neoplasm; palliative care.