Prevalence of bronchiectasis: a narrative review

Bronchiectasis is a chronic disease characterised by permanent dilatation of the bronchi, which leads to the development of chronic airways inflammation and clinical sequelae such as cough, sputum production, and recurrent infections. The clinical syndrome is typically associated with reduced quality of life and greater healthcare utilisation. Prevalence data for bronchiectasis remain limited in many parts of the world, and the available studies report heterogeneous results with overall prevalence rates reported between 52.5 and 1248.7 per 100,000. Over the past 25 years, the prevalence has steadily increased, likely due to increased awareness and improved diagnostic techniques. Bronchiectasis is most prevalent in older age groups, and it is more commonly found in females. It is associated with multiple comorbidities, including chronic obstructive pulmonary disease, chronic rhinosinusitis, asthma, hypertension, cardiovascular disease and symptoms of anxiety and depression. First Nations populations experience a disproportionately high burden of disease. Bronchiectasis is more common in First Nations patients living in rural or remote communities and in those with socioeconomic disadvantage. It is associated with a lower age at diagnosis than the general population, more frequently associated with higher smoking rates and childhood respiratory tract infections, including a higher prevalence of human T-cell lymphotropic virus 1 in Australian Indigenous populations. These factors contribute to more extensive bronchiectasis on imaging, higher exacerbation rates and greater mortality. The introduction of lung cancer screening programmes is likely to increase the incidental detection of asymptomatic bronchiectasis patients, whose consequences are likely to burden healthcare systems. It would be beneficial to determine risk factors for those likely to develop clinically significant disease and, therefore, to prioritise referrals for further assessment.