Incidence and mortality of idiopathic pulmonary fibrosis and sarcoidosis in the UK
- Correspondence to:
Professor R Hubbard
Respiratory Medicine, Clinical Sciences Building, City Hospital, Hucknall Road, Nottingham NG5 1PB, UK;
- Received 20 March 2006
- Accepted 21 June 2006
- Published Online First 14 July 2006
Background: Idiopathic pulmonary fibrosis (IPF) and sarcoidosis are common diagnoses in patients attending chest clinics, but little is known about the epidemiology of these diseases. We used data from a general practice database to provide information on the current incidence of IPF and sarcoidosis in the UK.
Methods: Data were extracted for all patients with a diagnosis of IPF or sarcoidosis between 1991 and 2003. The whole population of the database was used to calculate disease incidence stratified by age, sex, region, and time period. Poisson regression was used to compare the incidence between populations and Cox regression was used to compare survival between populations.
Results: 920 cases of IPF (mean age 71 years, 62% male) and 1019 cases of sarcoidosis (mean age 47 years, 47% male) were identified. The overall incidence rate per 100 000 person-years was 4.6 for IPF and 5.0 for sarcoidosis. The incidence of IPF increased progressively between 1991 and 2003 (p<0.00001), and was highest in Northern England and Scotland (p<0.0001). The survival of patients with IPF was stable over time. In contrast, the incidence of sarcoidosis was highest in London, West Midlands and Northern Ireland and remained stable over time.
Conclusions: The incidence of IPF has more than doubled between 1990 and 2003; this is not due to the ageing of the UK population or an increased ascertainment of milder cases. The incidence of sarcoidosis has not changed during this time period. Our findings suggest that more than 4000 new cases of IPF and 3000 new cases of sarcoidosis are currently diagnosed each year in the UK.
Published Online First 14 July 2006
Funding: British Lung Foundation.
Competing interests: none.