A decade on: Follow-up findings of indigenous children with bronchiectasis.

OBJECTIVE: The sole prospective longitudinal study of children with either chronic suppurative lung disease (CSLD) or bronchiectasis published in the current era was limited to a single center. We sought to extend this study by evaluating the longer-term clinical and lung function outcomes and their associated risk factors in Indigenous children of adolescents from Australia, Alaska, and New Zealand who participated in our previous CSLD or bronchiectasis studies during 2004-2010. METHODS: Between 2015 and 2018, we evaluated 131 out of 180 (72.8%) children of adolescents from the original studies at a single follow-up visit. We administered standardized questionnaires, reviewed medical records, undertook clinical examinations, performed spirometry, and scored available chest computed tomography scans. RESULTS: Participants were seen at a mean age of 12.3 years (standard deviation: 2.6) and a median of 9.0 years (range: 5.0-13.0) after their original recruitment. With increasing age, rates of acute lower respiratory infections (ALRI) declined, while lung function was mostly within population norms (median forced expiry volume in one-second = 90% predicted, interquartile range [IQR]: 81-105; forced vital capacity [FVC] = 98% predicted, IQR: 85-114). However, 43 out of 111 (38.7%) reported chronic cough episodes. Their overall global rating judged by symptoms, including ALRI frequency, examination findings, and spirometry was well (20.3%), stable (43.9%), or improved (35.8%). Multivariable regression identified household tobacco exposure and age at first ALRI-episode as independent risk factors associated with lower FVC% predicted values. CONCLUSION: Under our clinical care, the respiratory outcomes in late childhood or early adolescence are encouraging for these patient populations at high-risk of premature mortality. Prospective studies to further inform management throughout the life course into adulthood are now needed.

Three-weekly doses of azithromycin for indigenous infants hospitalized with bronchiolitis: a multicentre, randomized, placebo-controlled trial.

BACKGROUND: Bronchiolitis is a major health burden in infants globally, particularly among Indigenous populations. It is unknown if 3 weeks of azithromycin improve clinical outcomes beyond the hospitalization period. In an international, double-blind randomized controlled trial, we determined if 3 weeks of azithromycin improved clinical outcomes in Indigenous infants hospitalized with bronchiolitis. METHODS: Infants aged ≤24 months were enrolled from three centers and randomized to receive three once-weekly doses of either azithromycin (30 mg/kg) or placebo. Nasopharyngeal swabs were collected at baseline and 48 h later. Primary endpoints were hospital length of stay (LOS) and duration of oxygen supplementation monitored every 12 h until judged ready for discharge. Secondary outcomes were: day-21 symptom/signs, respiratory rehospitalizations within 6 months post-discharge and impact upon nasopharyngeal bacteria and virus shedding at 48 h. RESULTS: Two hundred nineteen infants were randomized (n = 106 azithromycin, n = 113 placebo). No significant between-group differences were found for LOS (median 54 h for each group, difference = 0 h, 95% CI: -6, 8; p = 0.8), time receiving oxygen (azithromycin = 40 h, placebo = 35 h, group difference = 5 h, 95% CI: -8, 11; p = 0.7), day-21 symptom/signs, or rehospitalization within 6 months (azithromycin n = 31, placebo n = 25 infants, p = 0.2). Azithromycin reduced nasopharyngeal bacterial carriage (between-group difference 0.4 bacteria/child, 95% CI: 0.2, 0.6; p < 0.001), but had no significant effect upon virus detection rates. CONCLUSION: Despite reducing nasopharyngeal bacterial carriage, three large once-weekly doses of azithromycin did not confer any benefit over placebo during the bronchiolitis illness or 6 months post hospitalization. Azithromycin should not be used routinely to treat infants hospitalized with bronchiolitis. CLINICAL TRIAL REGISTRATION: The trial was registered with the Australian and New Zealand Clinical Trials Register: Clinical trials number: ACTRN1261000036099.

Long-term azithromycin for Indigenous children with non-cystic-fibrosis bronchiectasis or chronic suppurative lung disease (Bronchiectasis Intervention Study): a multicentre, double-blind, randomised controlled trial.

BACKGROUND: Indigenous children in high-income countries have a heavy burden of bronchiectasis unrelated to cystic fibrosis. We aimed to establish whether long-term azithromycin reduced pulmonary exacerbations in Indigenous children with non-cystic-fibrosis bronchiectasis or chronic suppurative lung disease. METHODS: Between Nov 12, 2008, and Dec 23, 2010, we enrolled Indigenous Australian, Maori, and Pacific Island children aged 1-8 years with either bronchiectasis or chronic suppurative lung disease into a multicentre, double-blind, randomised, parallel-group, placebo-controlled trial. Eligible children had had at least one pulmonary exacerbation in the previous 12 months. Children were randomised (1:1 ratio, by computer-generated sequence with permuted block design, stratified by study site and exacerbation frequency [1-2 vs ≥3 episodes in the preceding 12 months]) to receive either azithromycin (30 mg/kg) or placebo once a week for up to 24 months. Allocation concealment was achieved by double-sealed, opaque envelopes; participants, caregivers, and study personnel were masked to assignment until after data analysis. The primary outcome was exacerbation (respiratory episodes treated with antibiotics) rate. Analysis of the primary endpoint was by intention to treat. At enrolment and at their final clinic visits, children had deep nasal swabs collected, which we analysed for antibiotic-resistant bacteria. This study is registered with the Australian New Zealand Clinical Trials Registry; ACTRN12610000383066. FINDINGS: 45 children were assigned to azithromycin and 44 to placebo. The study was stopped early for feasibility reasons on Dec 31, 2011, thus children received the intervention for 12-24 months. The mean treatment duration was 20·7 months (SD 5·7), with a total of 902 child-months in the azithromycin group and 875 child-months in the placebo group. Compared with the placebo group, children receiving azithromycin had significantly lower exacerbation rates (incidence rate ratio 0·50; 95% CI 0·35-0·71; p<0·0001). However, children in the azithromycin group developed significantly higher carriage of azithromycin-resistant bacteria (19 of 41, 46%) than those receiving placebo (four of 37, 11%; p=0·002). The most common adverse events were non-pulmonary infections (71 of 112 events in the azithromycin group vs 132 of 209 events in the placebo group) and bronchiectasis-related events (episodes or investigations; 22 of 112 events in the azithromycin group vs 48 of 209 events in the placebo group); however, study drugs were well tolerated with no serious adverse events being attributed to the intervention. INTERPRETATION: Once-weekly azithromycin for up to 24 months decreased pulmonary exacerbations in Indigenous children with non-cystic-fibrosis bronchiectasis or chronic suppurative lung disease. However, this strategy was also accompanied by increased carriage of azithromycin-resistant bacteria, the clinical consequences of which are uncertain, and will need careful monitoring and further study. FUNDING: National Health and Medical Research Council (Australia) and Health Research Council (New Zealand).