Ethnicity, socioeconomic status and the severity and course of non-cystic fibrosis bronchiectasis

This study evaluated whether there are ethnic factors which affect the severity and progression of bronchiectasis in our adult multi-ethnic population in Auckland, New Zealand.

Clinical records were reviewed from patients attending the outpatient facilities of our institution between 2007 and 2010. Data collected included demographics, clinical features, smoking status, self-reported ethnicity, socioeconomic status (NZDep), pulmonary function and sputum microbiology.

A total of 437 patients was identified: median age 65 years, 66% female, mean forced expiratory volume in the first second (FEV₁ ) 62.4% predicted, and 10.5% of patients had recurrent growth of Pseudomonas aeruginosa. Patients of Maori and Pacific ethnicity were overrepresented compared to the institution population catchment and had more severe impairment of lung function: mean % predicted FEV₁ for Pacific 52.0, Maori 58.6, European 68.6, Asian 64.2 (P < 0.0001). This was independent of socioeconomic status. However, no overall decline was seen in serial lung function measurements, either across the whole cohort or in any particular ethnic group.

Patients of Maori and Pacific ethnicity are both overrepresented and have more severe bronchiectasis in this cohort, independent of socioeconomic status. Ethnicity did not predict decline in pulmonary function. Further studies into genetic predisposition to bronchiectasis in Maori or Pacific people may be warranted.