Dual antibiotics for non-cystic fibrosis bronchiectasis

Head-to-head trials of antibiotics for bronchiectasis

BACKGROUND

The diagnosis of bronchiectasis is defined by abnormal dilation of the airways related to a pathological mechanism of progressive airway destruction that is due to a 'vicious cycle' of recurrent bacterial infection, inflammatory mediator release, airway damage, and subsequent further infection. Antibiotics are the main treatment option for reducing bacterial burden in people with exacerbations of bronchiectasis and for longer-term eradication, but their use is tempered against potential adverse effects and concerns regarding antibiotic resistance. The comparative effectiveness, cost-effectiveness, and safety of different antibiotics have been highlighted as important issues, but currently little evidence is available to help resolve uncertainty on these questions.

OBJECTIVES

To evaluate the comparative effects of different antibiotics in the treatment of adults and children with bronchiectasis.

SEARCH METHODS

We identified randomised controlled trials (RCTs) through searches of the Cochrane Airways Group Register of trials and online trials registries, run 30 April 2018. We augmented these with searches of the reference lists of published studies.

SELECTION CRITERIA

We included RCTs reported as full-text articles, those published as abstracts only, and unpublished data. We included adults and children (younger than 18 years) with a diagnosis of bronchiectasis by bronchography or high-resolution computed tomography who reported daily signs and symptoms, such as cough, sputum production, or haemoptysis, and those with recurrent episodes of chest infection; we included studies that compared one antibiotic versus another when they were administered by the same delivery method.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial selection, data extraction, and risk of bias. We assessed overall quality of the evidence using GRADE criteria. We made efforts to collect missing data from trial authors. We have presented results with their 95% confidence intervals (CIs) as mean differences (MDs) or odds ratios (ORs).

MAIN RESULTS

Four randomised trials were eligible for inclusion in this systematic review - two studies with 83 adults comparing fluoroquinolones with β-lactams and two studies with 55 adults comparing aminoglycosides with polymyxins.None of the included studies reported information on exacerbations - one of our primary outcomes. Included studies reported no serious adverse events - another of our primary outcomes - and no deaths. We graded this evidence as low or very low quality. Included studies did not report quality of life. Comparison between fluoroquinolones and β-lactams (amoxicillin) showed fewer treatment failures in the fluoroquinolone group than in the amoxicillin group (OR 0.07, 95% CI 0.01 to 0.32; low-quality evidence) after 7 to 10 days of therapy. Researchers reported that Pseudomonas aeruginosa infection was eradicated in more participants treated with fluoroquinolones (Peto OR 20.09, 95% CI 2.83 to 142.59; low-quality evidence) but provided no evidence of differences in the numbers of participants showing improvement in sputum purulence (OR 2.35, 95% CI 0.96 to 5.72; very low-quality evidence). Study authors presented no evidence of benefit in relation to forced expiratory volume in one second (FEV₁). The two studies that compared polymyxins versus aminoglycosides described no clear differences between groups in the proportion of participants with P aeruginosa eradication (OR 1.40. 95% CI 0.36 to 5.35; very low-quality evidence) or improvement in sputum purulence (OR 0.16, 95% CI 0.01 to 3.85; very low-quality evidence). The evidence for changes in FEV₁ was inconclusive. Two of three trials reported adverse events but did not report the proportion of participants experiencing one or more adverse events, so we were unable to interpret the information.

AUTHORS' CONCLUSIONS

Limited low-quality evidence favours short-term oral fluoroquinolones over beta-lactam antibiotics for patients hospitalised with exacerbations. Very low-quality evidence suggests no benefit from inhaled aminoglycosides verus polymyxins. RCTs have presented no evidence comparing other modes of delivery for each of these comparisons, and no RCTs have included children. Overall, current evidence from a limited number of head-to-head trials in adults or children with bronchiectasis is insufficient to guide the selection of antibiotics for short-term or long-term therapy. More research on this topic is needed.

Dual antibiotics for bronchiectasis

BACKGROUND

Bronchiectasis is a chronic respiratory disease characterised by abnormal and irreversible dilatation of the smaller airways and associated with a mortality rate greater than twice that of the general population. Antibiotics serve as front-line therapy for managing bacterial load, but their use is weighed against the development of antibiotic resistance. Dual antibiotic therapy has the potential to suppress infection from multiple strains of bacteria, leading to more successful treatment of exacerbations, reduced symptoms, and improved quality of life. Further evidence is required on the efficacy of dual antibiotics in terms of management of exacerbations and extent of antibiotic resistance.

OBJECTIVES

To evaluate the effects of dual antibiotics in the treatment of adults and children with bronchiectasis.

SEARCH METHODS

We identified studies from the Cochrane Airways Group Specialised Register (CAGR), which includes the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), Allied and Complementary Medicine (AMED), and PsycINFO, as well as studies obtained by handsearching of journals/abstracts. We also searched the following trial registries: US National Institutes of Health Ongoing Trials Register, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform. We imposed no restriction on language of publication. We conducted our search in October 2017.

SELECTION CRITERIA

We searched for randomised controlled trials comparing dual antibiotics versus a single antibiotic for short-term (< 4 weeks) or long-term management of bronchiectasis diagnosed in adults and/or children by bronchography, plain film chest radiography, or high-resolution computed tomography. Primary outcomes included exacerbations, length of hospitalisation, and serious adverse events. Secondary outcomes were response rates, emergence of resistance to antibiotics, systemic markers of infection, sputum volume and purulence, measures of lung function, adverse events/effects, deaths, exercise capacity, and health-related quality of life. We did not apply outcome measures as selection criteria.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the titles and abstracts of 287 records, along with the full text of seven reports. Two studies met review inclusion criteria. Two review authors independently extracted outcome data and assessed risk of bias. We extracted data from only one study and conducted GRADE assessments for the following outcomes: successful treatment of exacerbation; response rates; and serious adverse events.

MAIN RESULTS

Two randomised trials assessed the effectiveness of oral plus inhaled dual therapy versus oral monotherapy in a total of 118 adults with a mean age of 62.8 years. One multi-centre trial compared inhaled tobramycin plus oral ciprofloxacin versus ciprofloxacin alone, and one single-centre trial compared nebulised gentamicin plus systemic antibiotics versus a systemic antibiotic alone. Published papers did not report study funding sources.Effect estimates from one small study with 53 adults showed no evidence of treatment benefit with oral plus inhaled dual therapy for the following primary outcomes at the end of the study: successful management of exacerbation - cure at day 42 (odds ratio (OR) 0.66, 95% confidence interval (CI) 0.22 to 2.01; 53 participants; one study; very low-quality evidence); number of participants with Pseudomonas aeruginosa eradication at day 21 (OR 2.33, 95% CI 0.66 to 8.24; 53 participants; one study; very low-quality evidence); and serious adverse events (OR 0.48, 95% CI 0.08 to 2.87; 53 participants; one study; very low-quality evidence). Similarly, researchers provided no evidence of treatment benefit for the following secondary outcomes: clinical response rates - relapse at day 42 (OR 0.57, 95% CI 0.12 to 2.69; 53 participants; one study; very low-quality evidence); microbiological response rate at day 21 - eradicated (OR 2.40, 95% CI 0.67 to 8.65; 53 participants; one study; very low-quality evidence); and adverse events - incidence of wheeze (OR 5.75, 95% CI 1.55 to 21.33). Data show no evidence of benefit in terms of sputum volume, lung function, or antibiotic resistance. Outcomes from a second small study with 65 adults, available only as an abstract, were not included in the quantitative data synthesis. The included studies did not report our other primary outcomes: duration; frequency; and time to next exacerbation; nor our secondary outcomes: systemic markers of infection; exercise capacity; and quality of life. We did not identify any trials that included children.

AUTHORS' CONCLUSIONS

A small number of studies in adults have generated high-quality evidence that is insufficient to inform robust conclusions, and studies in children have provided no evidence. We identified only one dual-therapy combination of oral and inhaled antibiotics. Results from this single trial of 53 adults that we were able to include in the quantitative synthesis showed no evidence of treatment benefit with oral plus inhaled dual therapy in terms of successful treatment of exacerbations, serious adverse events, sputum volume, lung function, and antibiotic resistance. Further high-quality research is required to determine the efficacy and safety of other combinations of dual antibiotics for both adults and children with bronchiectasis, particularly in terms of antibiotic resistance.

Oral versus inhaled antibiotics for bronchiectasis

BACKGROUND

Bronchiectasis is a chronic inflammatory disease characterised by a recurrent cycle of respiratory bacterial infections associated with cough, sputum production and impaired quality of life. Antibiotics are the main therapeutic option for managing bronchiectasis exacerbations. Evidence suggests that inhaled antibiotics may be associated with more effective eradication of infective organisms and a lower risk of developing antibiotic resistance when compared with orally administered antibiotics. However, it is currently unclear whether antibiotics are more effective when administered orally or by inhalation.

OBJECTIVES

To determine the comparative efficacy and safety of oral versus inhaled antibiotics in the treatment of adults and children with bronchiectasis.

SEARCH METHODS

We identified studies through searches of the Cochrane Airways Group's Specialised Register (CAGR), which is maintained by the Information Specialist for the group. The Register contains trial reports identified through systematic searches of bibliographic databases including the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL, AMED, and PsycINFO, and handsearching of respiratory journals and meeting abstracts. We also searched ClinicalTrials.gov and the WHO trials portal. We searched all databases in March 2018 and imposed no restrictions on language of publication.

SELECTION CRITERIA

We planned to include studies which compared oral antibiotics with inhaled antibiotics. We would have considered short-term use (less than four weeks) for treating acute exacerbations separately from longer-term use as a prophylactic (4 weeks or more). We would have considered both intraclass and interclass comparisons. We planned to exclude studies if the participants received continuous or high-dose antibiotics immediately before the start of the trial, or if they have received a diagnosis of cystic fibrosis (CF), sarcoidosis, active allergic bronchopulmonary aspergillosis or active non-tuberculous Mycobacterial infection.

DATA COLLECTION AND ANALYSIS

Two review authors independently applied study inclusion criteria to the searches and we planned for two authors to independently extract data, assess risk of bias and assess overall quality of the evidence using GRADE criteria. We also planned to obtain missing data from the authors where possible and to report results with 95% confidence intervals (CIs).

MAIN RESULTS

We identified 313 unique records through database searches and a further 21 records from trial registers. We excluded 307 on the basis of title and abstract alone and a further 27 after examining full-text reports. No studies were identified for inclusion in the review.

AUTHORS' CONCLUSIONS

There is currently no evidence indicating whether orally administered antibiotics are more beneficial compared to inhaled antibiotics. The recent ERS bronchiectasis guidelines provide a practical approach to the use of long-term antibiotics. New research is needed comparing inhaled versus oral antibiotic therapies for bronchiectasis patients with a history of frequent exacerbations, to establish which approach is the most effective in terms of exacerbation prevention, quality of life, treatment burden, and antibiotic resistance.

Healthcare Cost and Utilization before and after Diagnosis of Pseudomonas aeruginosa among Patients with Non-Cystic Fibrosis Bronchiectasis in the U.S

Non-cystic fibrosis bronchiectasis (NCFBE) is a rare, chronic lung disease characterized by bronchial inflammation and permanent airway dilation. Chronic infections with P. aeruginosa have been linked to higher morbidity and mortality. To understand the impact of P. aeruginosa in NCFBE on health care costs and burden, we assessed healthcare costs and utilization before and after P. aeruginosa diagnosis. Using data from 2007 to 2013 PharMetrics Plus administrative claims, we included patients with ≥2 claims for bronchiectasis and >1 claim for P. aeruginosa; then excluded those with a claim for cystic fibrosis. Patients were indexed at first claim for P. aeruginosa and were required to have >12 months before and after the index P. aeruginosa. The mean differences in utilization and costs were assessed using paired Student's t-tests for statistical significance. Mean total healthcare costs per patient were $36,213 pre-P. aeruginosa diagnosis versus $67,764 post-P. aeruginosa, an increase of 87% (p < 0.0001). Inpatient costs represented the largest proportion of total healthcare costs post-P. aeruginosa (54%) with an increase of four hospitalizations per patient (p < 0.0001). NCFBE patients with evidence of P. aeruginosa incur substantially greater healthcare costs and utilization after P. aeruginosa diagnosis. Future research should explore methods of earlier identification of NCFBE patients with P. aeruginosa, as this may lead to fewer severe exacerbations, thereby resulting in a reduction in hospitalizations and healthcare costs.