Atorvastatin as a stable treatment in bronchiectasis: a randomised controlled trial

Interventions for bronchiectasis: an overview of Cochrane systematic reviews

BACKGROUND

Bronchiectasis is a chronic respiratory disease characterised by abnormal dilatation of the bronchi, and presents typically with a chronic productive cough (or chronic wet cough in children) and recurrent infective exacerbations. It significantly impacts daily activities and quality of life, and can lead to recurrent hospitalisations, severe lung function impairment, respiratory failure and even death.

OBJECTIVES

To provide an overview of the efficacy and safety of interventions for adults and children with bronchiectasis from Cochrane reviews.To identify gaps in the evidence base that will inform recommendations for new research and reviews, and to summarise information on reported outcomes and make recommendations for the reporting of standard outcomes in future trials and reviews.

METHODS

We included Cochrane reviews of non-cystic fibrosis (CF) bronchiectasis. We searched the Cochrane Database of Systematic Reviews. The search is current to 11 February 2015. We also identified trials that were potentially eligible for, but not currently included in, published reviews to make recommendations for new Cochrane reviews. We assessed the quality of included reviews using the AMSTAR criteria. We presented an evidence synthesis of data from reviews alongside an evidence map of clinical trials and guideline data. The primary outcomes were exacerbations, lung function and quality of life.

MAIN RESULTS

We included 21 reviews but extracted data from, and rated the quality of, only nine reviews that reported results for people with bronchiectasis alone. Of the reviews with no usable data, two reviews included studies with mixed clinical populations where data were not reported separately for people with bronchiectasis and 10 reviews did not contain any trials. Of the 40 studies included across the nine reviews, three (number of participants nine to 34) included children. The studies ranged from single session to year-long studies. Each review included from one to 11 trials and 28 (70%) trials in the overview included 40 or fewer participants. The total number of participants included in reviews ranged from 40 to 1040. The age range of adult participants was from 36 to 73 years and children ranged from six to 16 years. The proportion of male participants ranged from 21% to 72%. Where reported, mean baseline forced expiratory volume in one second (FEV1) ranged from 1.17 L to 1.66 L and from 47% to 88% predicted. Most of the reviews had search dates older than two years.We have summarised the published evidence as outlined in Cochrane reviews, but it was not possible to draw definitive conclusions. There was inconclusive evidence on the use of long-term antibiotics and nebulised hypertonic saline for reducing exacerbation frequency and evidence that human deoxyribonuclease (RhDNase) increases exacerbation frequency. Improvements in lung function were reported for inhaled corticosteroids (ICS) though this was small and not clinically relevant. Evidence of benefit for hyperosmolar agents and mucolytics was inconclusive. There was limited evidence of improvements in quality of life with airway clearance techniques and physical therapy but evidence of benefit for hyperosmolar agents was inconclusive. Secondary outcomes were not clearly reported in all trials in the included reviews. Improvements in dyspnoea, wheeze and cough-free days were reported for small trials of ICS and LABA (long-acting beta2-agonsts)/ICS and cough reduction was also reported for a small bromhexine trial. Reduction in sputum production was reported for long-term antibiotics and airway clearance techniques but evidence of benefit for hyperosmolar agents was inconclusive.Adverse events were included as outcomes in seven reviews. The review of long-term (four weeks to one year) prophylactic courses of antibiotics reported significantly more cases of wheeze (Peto odd ratio (OR) 8.56, 95% confidence intervals (CI) 1.63 to 44.93), dyspnoea (12 versus three, P value = 0.01) and chest pain (seven versus zero, P value = 0.01) from the same trial (74 participants) but no differences in occurrence of diarrhoea, rash or number of withdrawals. In the review of mucolytics versus placebo, relevant outcomes were not reported for erdosteine comparisons and no significant adverse effects were reported for bromhexine, though adverse events were associated with RhDNase (OR 28.19, 95% CI 3.77 to 210.85, 1 study). Of the remaining five reviews, adverse events were not reported in the single trials included in the ICS review or the physical therapy review and the impact of adverse events in the single trial included in the inhaled LABA/ICS combination versus ICS review were unclear. The reviews of short-term courses of antibiotics and inhaled hyperosmolar agents reported no significant differences in occurrence of adverse events. Fewer admissions to hospital were reported for long-term antibiotics, but this outcome was not reported in all reviews. No reviews reported differences in mortality, but again this outcome was not included in all reviews.We did not explicitly include antibiotic resistance as an outcome in the review, but this was unclear in the Cochrane reviews and evidence from other trials should be considered.We rated all reviews as high quality (AMSTAR), though opportunities for improved reporting (e.g. summary of findings and GRADE evaluation of the evidence) were identified for inclusion in future updates of the reviews. However, the majority of trials were not high quality and confidence in the effects of treatments, therefore, requires additional evidence from larger and more methodologically robust trials. We evaluated the overall coverage of important topics in bronchiectasis by mapping the quality of the current evidence base against published guidelines and identifying high priority areas for new research on; use of short-course and long-term antibiotics, ICS and oral corticosteroids, inhaled hyperosmolars, mucolytics, and use of airway clearance techniques.

AUTHORS' CONCLUSIONS

This overview clearly points to significant opportunities for further research aimed at improving outcomes for people with bronchiectasis. We have highlighted important endpoints for studies (particularly exacerbations, quality of life and lung function), and areas of clinical practice that are in most urgent need of evidence-based support (including long-term antibiotics, ICSs and mucolytics).As the evidence is confined to small trials of short duration, it is not currently possible to assess the balance between the benefits and potential harms of treatments for bronchiectasis.

How best to measure cough clinically

It is possible to measure cough by assessing its severity, frequency, intensity, associated urge and its impact on quality of life. Cough severity can simply be assessed with a Visual Analogue Scale. Cough frequency can be assessed objectively with cough frequency monitors. Validated cough monitors include the Leicester Cough Monitor and the VitaloJAK. Cough reflex sensitivity measurement is better used to investigate the mechanisms of action of antitussive medications, rather than assessing efficacy. Health-Related Quality of Life measures are available to assess the impact of cough; they include the validated Leicester Cough Questionnaire and Cough-specific Quality of Life Questionnaire for adult patients. It is best to assess cough with a combination of subjective and objective tools, to capture its wide-ranging impact.

Management of bronchiectasis in adults

Formerly regarded as a rare disease, bronchiectasis is now increasingly recognised and a renewed interest in the condition is stimulating drug development and clinical research. Bronchiectasis represents the final common pathway of a number of infectious, genetic, autoimmune, developmental and allergic disorders and is highly heterogeneous in its aetiology, impact and prognosis. The goals of therapy should be: to improve airway mucus clearance through physiotherapy with or without adjunctive therapies; to suppress, eradicate and prevent airway bacterial colonisation; to reduce airway inflammation; and to improve physical functioning and quality of life. Fortunately, an increasing body of evidence supports interventions in bronchiectasis. The field has benefited greatly from the introduction of evidence-based guidelines in some European countries and randomised controlled trials have now demonstrated the benefit of long-term macrolide therapy, with accumulating evidence for inhaled therapies, physiotherapy and pulmonary rehabilitation. This review provides a critical update on the management of bronchiectasis focussing on emerging evidence and recent randomised controlled trials.

Genetics, diagnosis, and future treatment strategies for primary ciliary dyskinesia

INTRODUCTION

Primary ciliary dyskinesia (PCD) is a genetically heterogeneous recessive disorder resulting in chronic oto-sino-pulmonary disease. While PCD is estimated to occur in 1 in 20,000 individuals, fewer than 1,000 patients in the US have a well-established diagnosis.

AREAS COVERED

We provide an overview of the clinical manifestations of PCD, describe the evolution of diagnostic methods, and critique the literature on management of PCD.

EXPERT OPINION

Although interest in clinical studies in non-CF bronchiectasis has increased in recent years, some of whom enroll patients with PCD, the literature regarding therapy for PCD as a distinct entity is lacking, as the numbers are small, and there have been no sub-analyses published. However, with improved screening and diagnostic methods, the development of clinical and research consortiums, and actively enrolling registries of PCD patients, the environment is conducive to perform longitudinal studies of disease course and therapeutic studies to alter that course.

Capsaicin cough sensitivity and the association with clinical parameters in bronchiectasis

BACKGROUND

Cough hypersensitivity has been common among respiratory diseases.

OBJECTIVE

To determine associations of capsaicin cough sensitivity and clinical parameters in adults with clinically stable bronchiectasis.

METHODS

We recruited 135 consecutive adult bronchiectasis patients and 22 healthy subjects. History inquiry, sputum culture, spirometry, chest high-resolution computed tomography (HRCT), Leicester Cough Questionnaire scoring, Bronchiectasis Severity Index (BSI) assessment and capsaicin inhalation challenge were performed. Cough sensitivity was measured as the capsaicin concentration eliciting at least 2 (C2) and 5 coughs (C5).

RESULTS

Despite significant overlap between healthy subjects and bronchiectasis patients, both C2 and C5 were significantly lower in the latter group (all P<0.01). Lower levels of C5 were associated with a longer duration of bronchiectasis symptoms, worse HRCT score, higher 24-hour sputum volume, BSI and sputum purulence score, and sputum culture positive for P. aeruginosa. Determinants associated with increased capsaicin cough sensitivity, defined as C5 being 62.5 µmol/L or less, encompassed female gender (OR: 3.25, 95%CI: 1.35-7.83, P<0.01), HRCT total score between 7-12 (OR: 2.57, 95%CI: 1.07-6.173, P = 0.04), BSI between 5-8 (OR: 4.05, 95%CI: 1.48-11.06, P<0.01) and 9 or greater (OR: 4.38, 95%CI: 1.48-12.93, P<0.01).

CONCLUSION

Capsaicin cough sensitivity is heightened in a subgroup of bronchiectasis patients and associated with the disease severity. Gender and disease severity, but not sputum purulence, are independent determinants of heightened capsaicin cough sensitivity. Current testing for cough sensitivity diagnosis may be limited because of overlap with healthy subjects but might provide an objective index for assessment of cough in future clinical trials.