11th January 2024

Epidemiology

Registries of various ILDs have been initiated in many countries, yet it remains challenging to determine incidence accurately due to differences in diagnostic criteria used and rarity of many of these conditions. In England alone, between 2,000 and 4,000 individuals are diagnosed with ILD every year. The most common subtypes are sarcoidosis, HP and IPF, accounting for 50-75% of all cases. Sarcoidosis incidence is estimated to be between 3 to 5 cases per 100,000 people per year in the UK, and it seems to be more common in patients of Afro-Caribbean descent.

The majority of ILDs are more common in older individuals, but sarcoidosis, connective tissue disease-associated ILD, pulmonary Langerhans cell histiocytosis, and inherited forms of ILD typically present between the ages of 20 and 40. Pneumoconiosis and IPF occur more frequently in men, while CTD-ILD is more common in women.