Introduction and objectives Spontaneous Pneumothorax (SP) is a common pathology. Incidence rates are quoted as 16–24 and 1.2–6 per 100,000 cases per annum for males and females respectively, based on two studies in single centres (45 years ago, USA; 30 years ago, Sweden) and 4-year periods of national data in UK (1991–4) and France (2008–2011).
The aim of this study is to determine the incidence and recurrence of spontaneous pneumothorax in a larger dataset in England.
Methods An all-England Hospital Episode Statistics (HES) dataset from 1968–2011 was used to determine the incidence of Spontaneous Pneumothorax using International Classification of Diseases codes as the main diagnosis in a hospital admission. A record-linked HES dataset (only available from 1999–2011) was used to distinguish between Primary and Secondary Spontaneous Pneumothorax (PSP and SSP) and to determine the risk of a second pneumothorax within specified time intervals. SSP was defined as the patient having a diagnosis of a chronic lung disease (e.g. COPD, emphysema, lung malignancy, asthma, bronchiectasis, sarcoidosis) made at any time covered by the linked data.
Results and discussion From 1968–2011, in a population of 50 million, there were a total of 246,534 episodes of spontaneous pneumothorax (no data for 1986–89). In 1999–2011, the average annual incidence was 9.1 per 100,000 males and 3.2 per 100,000 females for PSP; 11.9 and 4.7 for SSP; and 21.0 and 7.9 for SP overall. The incidence of SP appears to be increasing (Figure 1): it was 12.5 (95% confidence interval 12.2–12.8) in 1999 and 13.6 (13.3–13.9) in 2011. It is unclear whether this reflects a true rise in new cases, better reporting or increasing recurrence rates.
The overall risk of recurrence is 13.5% within 1 year (18.7% within 5 years). Recurrence is more common in SSP than PSP at 1 year (16.1% vs 10.6%) and 5 years (21.2% vs 14.7%).
Conclusions This is the largest epidemiological study of pneumothorax to date. These data only cover hospitalised pneumothorax, and therefore may be a conservative estimate of the true burden of disease. Pneumothorax appears to be increasing in incidence.