Asthma as aetiology of bronchiectasis in Finland

By definition bronchiectasis (BE) means destructed structure of normal bronchus as a consequence of frequent bacterial infections and inflammation. In many senses, BE is a neglected orphan disease. A recent pan-European registry study, EMBARC, has been set up in order to better understand its pathophysiology, better phenotype patients, and to individualize their management.

To examine the aetiology and co-morbidity of BE in the capital area in Finland.

Two hundred five patients with BE diagnosis and follow up visits between 2016 and 2017 in Helsinki University Hospital were invited to participate in the study. Baseline demographics, lung functions, imaging, microbiological, and therapeutic data, together with co-morbidities were entered into EMBARC database. Clinical characteristics, aetiologic factors, co-morbidities, and risk factors for extensive BE were explored.

To the study included 95 adult patients and seventy nine percent of the BE patients were women. The mean age was 69 years (SD ± 13). Asthma was a comorbid condition in 68% of the patients but in 26% it was estimated to be the cause of BE. Asthma was aetiological factor for BE if it had been diagnosed earlier than BE. As 41% BE were idiopathic, in 11% the disorder was postinfectious and others were associated to rheumatic disease, Alpha-1-antitrypsin deficiency, IgG deficiency and Kartagener syndrome. The most common co-morbidities in addition to asthma were cardiovascular disease (30%), gastroesophageal reflux disease (26%), overweight (22%), diabetes (16%), inactive neoplasia (15%), and immunodeficiency (12%). Extensive BE was found in 68% of BE patients in whom four or more lobes were affected. Risk factors for extensive BE were asthma (OR 2.7), asthma as aetiology for BE (OR 4.3), and rhinosinusitis (OR 3.1).

Asthma was associated to BE in 68% and it was estimated as aetiology in every fourth patient. However, retrospectively, it is difficult to exclude asthma as a background cause in patients with asthma-like symptoms and respiratory infections. We propose asthma as an aetiology factor for BE if it is diagnosed earlier than BE. Asthma and rhinosinusitis were predictive for extensive BE.