New Zealand national incidence of bronchiectasis "too high" for a developed country

Abstract

Aims: To prospectively estimate the incidence of bronchiectasis among New Zealand (NZ) children, to consider aetiology and severity, and to evaluate regional and ethnic variation.

Methodology: NZ paediatricians were surveyed monthly for new cases of bronchiectasis during 2001 and 2002 via the NZ paediatric surveillance unit (with coverage of >94% of NZ paediatricians). Notified cases had their computed tomography scans reviewed and scored for severity. Confirmed cases were followed up by postal questionnaire one year after diagnosis. Demographic, aetiological, and severity data were collected.

Results: Ninety nine notifications were received. Sixty five cases were confirmed. An overall incidence of 3.7 per 100,000 under 15 year old children per year was estimated. Incidence was highest in Pacific children at 17.8 compared with 4.8 in Maori, 1.5 in NZ European, and 2.4 other per 100,000 per year. Incidence varied significantly by region. The median age at diagnosis was 5.2 years; the majority had symptoms for more than two years. Eighty three per cent had bilateral disease, with a median of three lobes affected, mean FEV1 of 77% predicted, and modified Bhalla HRCT score of 18.

Conclusions: The incidence of bronchiectasis is high in NZ children, nearly twice the rate for cystic fibrosis and seven times that of Finland, the only other country reporting a childhood national rate. Incidence varied substantially between ethnicities. Most cases developed disease in early childhood and had delayed diagnosis.

Figure 1

Regional incidence.

Figure 2

Proportion of cases with each lobe (and lingual) affected.