While identifying the underlying aetiology is a key part of bronchiectasis management, the prevalence and impact of identifying the aetiologies on clinical management remain unclear. We aimed to determine the etiological spectrum of bronchiectasis, and how often etiological assessment could lead to the changes in patients' management. A comprehensive search was conducted using MEDLINE (via PubMed) and EMBASE for observational studies published before October 2015 reporting aetiologies in adults with bronchiectasis. Of the 8216 citations identified, 56 studies including 8608 adults with bronchiectasis were relevant for this systematic review. The crude prevalence for the identified aetiologies ranged from 18% to 95%, which possibly resulted from the differences in the geographic regions and diagnostic workup. Post-infective (29.9%), immunodeficiency (5%), chronic obstructive pulmonary disease (3.9%), connective tissue disease (3.8%), ciliary dysfunction (2.5%), allergic bronchopulmonary aspergillosis (2.6%) were the most common aetiologies. In 1577 patients (18.3%), identifying the aetiologies led to changes in patient's management. Aetiologies varied considerably among different geographic regions (P < 0.001). Intensive investigations of these aetiologies might help change patient's management and therefore should be incorporated into routine clinical practice.

These findings indicate that COPD, even in mild to moderate patients, had greater impaired markers of subclinical atherosclerosis and cardiovascular risk. However, further studies are still needed to address confounders, such as age, smoking, hypertension, diabetes etc, which might affect the associations in COPD patients.

Compared with healthy subjects, bronchiectasis patients have greater risks of endothelial dysfunction which is independent of previously well-studied risk factors, calling for the vigilance to screen early for vascular changes to minimize the future risks of cardiovascular events.

BackgroundCardiovascular disease are common co-morbidities in bronchiectasis and contribute substantially to disease burden and mortality. Brachial-ankle pulse wave velocity (baPWV), a measure of arterial stiffness, has a strong predictive value for cardiovascular event. We hypothesized that baPWV would be increased in steady-state bronchiectasis patients, and correlates with the degree of systemic inflammation and disease severity assessed with Bronchiectasis Severity Index and FACED scores.MethodsEighty patients with steady-state bronchiectasis and 80 age- and sex-matched controls were enrolled. BaPWV was measured as an indicator of arterial stiffness. Demographic, clinical indices, radiology, spirometry, sputum bacteriology and systemic inflammatory mediators were also assessed.ResultsBronchiectasis patients had significantly increased baPWV [median 1514 cm/s vs. 1352 cm/s, P = 0.0003] compared with control subjects. BaPWV significantly correlated with Bronchiectasis Severity Index (rho = 0.65, P < 0.001) and FACED (rho = 0.49, P < 0.001) scores. In multivariate regression analysis, age, Pseudomonas aeruginosa colonization, systolic blood pressure, body-mass index and exacerbation frequency in the last 12 months, but not systemic inflammatory markers, were independent factors influencing on baPWV in bronchiectasis patient after adjustment for other clinical variables. Reproducibility of baPWV measurement was good.ConclusionBronchiectasis patients have increased arterial stiffness compared with control subjects, which correlates with disease severity, but not systemic inflammatory markers. Age, Pseudomonas aeruginosa colonization, systolic blood pressure, body-mass index and exacerbation frequency in last 12 months might independently predict the severity of arterial stiffness in bronchiectasis. Therefore, arterial stiffness might have contributed to the increased risks of developing cardiovascular diseases in bronchiectasis.Electronic supplementary materialThe online version of this article (10.1186/s12931-018-0790-3) contains supplementary material, which is available to authorized users.