Bronchiectasis in adults: epidemiology, assessment of severity and prognosis

This article reviews the epidemiology, severity and impact of bronchiectasis in adults. Bronchiectasis is an increasingly recognised clinical syndrome characterised by bronchial dilatation on CT scanning in association with a history of cough, sputum production and/or recurrent respiratory infections. It may complicate a large number of underlying disorders and is increasingly recognised in association with other airway diseases, including COPD. Important considerations in the epidemiology of bronchiectasis include our limited knowledge of how to define the disease and therefore a lack of large-scale epidemiological studies to define how common it is. The impact of the disease is considerable in terms of healthcare visits, antibiotic use, hospital admissions and mortality. The severity of disease varies greatly, from patients with infrequent exacerbations and few symptoms, to patients with hospital admissions, poor quality of life and greatly reduced survival. Rational therapy requires accurate severity assessment in order to identify those patients most likely to benefit. We have recently described a bronchiectasis severity index (BSI) which has been derived and validated in a multicentre international study and shown to predict mortality, hospital admissions, exacerbations and quality of life. Additional validation data have been published in the past 12 months demonstrating that the BSI accurately stratifies patients according to their disease burden and future risk.