11th January 2024

Breathlessness

The most common presenting complaint is progressive breathlessness, or dyspnoea, on exertion. Timing of progression is diagnostically important, although some ILDs can present both acutely and chronically (see Table 4). Particular care should be taken to differentiate ILDs with indolent presentation from other common causes of dyspnoea, such as chronic obstructive pulmonary disease (COPD) and heart failure.

It is important to check if the breathlessness is continuous or episodic. If episodic with asymptomatic periods in between, ascertain whether there is a clear pattern, e.g. symptoms are worse in the morning/on weekdays/in winter, which could point towards an environmental trigger. On the other hand, episodic breathlessness in the absence of a clear pattern could be suggestive of EGPA, COP or allergic bronchopulmonary aspergillosis (ABPA). Continuous symptoms are more suggestive of fibrotic ILDs such as IPF.

Table 4: diffuse lung disease and time of onset. Adjusted from Oxford Handbook of Respiratory Medicine, 4th ed.