Postinfectious cough: ACCP evidence-based clinical practice guidelines

Zhisou powder suppresses airway inflammation in LPS and CS-induced post-infectious cough model mice via TRPA1/TRPV1 channels

ETHNOPHARMACOLOGICAL RELEVANCE

Zhisou Powder (ZSP), a traditional Chinese medicine (TCM) prescription, has been widely used in the clinic for the treatment of post-infectious cough (PIC). However, the exact mechanism is not clear.

AIM OF THE STUDY

The aim of this study was to investigate the ameliorative effect of ZSP on PIC in mice. The possible mechanisms of action were screened based on network pharmacology, and the potential mechanisms were explored through molecular docking and in vivo experimental validation.

MATERIALS AND METHODS

Lipopolysaccharide (LPS) (80μg/50 μL) was used to induce PIC in mice, followed by daily exposure to cigarette smoke (CS) for 30 min for 30 d to establish PIC model. The effects of ZSP on PIC mice were observed by detecting the number of coughs and cough latency, peripheral blood and bronchoalveolar lavage fluid (BALF) inflammatory cell counts, enzyme-linked immunosorbent assay (ELISA), and histological analysis. The core targets and key pathways of ZSP on PIC were analyzed using network pharmacology, and TRPA1 and TRPV1 were validated using RT-qPCR and western blotting assays.

RESULTS

ZSP effectively reduced the number of coughs and prolonged the cough latency in PIC mice. Airway inflammation was alleviated by reducing the expression levels of the inflammatory mediators TNF-α and IL-1β. ZSP modulated the expression of Substance P, Calcitonin gene-related peptide (CGRP), and nerve growth factor (NGF) in BALF. Based on the results of network pharmacology, the mechanism of action of ZSP may exert anti-neurogenic airway-derived inflammation by regulating the expression of TRPA1 and TRPV1 through the natural active ingredients α-spinastero, shionone and didehydrotuberostemonine.

CONCLUSION

ZSP exerts anti-airway inflammatory effects through inhibition of TRPA1/TRPV1 channels regulating neuropeptides to alleviate cough hypersensitivity and has a favorable therapeutic effect on PIC model mice. It provides theoretical evidence for the clinical application of ZSP.

Xingbei antitussive granules ameliorate cough hypersensitivity in post-infectious cough guinea pigs by regulating tryptase/PAR2/TRPV1 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Xingbei antitussive granules (XB) is a classic Chinese Medicine prescription for treating post-infectious cough(PIC), based on the Sanao Decoction from Formularies of the Bureau of People's Welfare Pharmacies in the Song Dynasty and Jiegeng decoction from Essentials of the Golden Chamber in the Han Dynasty. However, the therapeutic effects and pharmacological mechanisms are still ambiguous. In the present study, we endeavored to elucidate these underlying mechanisms.

AIMS OF THE STUDY

This study aimed to explore the potential impact and mechanism of XB on PIC, and provide a scientific basis for its clinical application.

MATERIALS AND METHODS

Cigarette smoking (CS) combined with lipopolysaccharide (LPS) nasal drops were administered to induce the PIC guinea pig with cough hypersensitivity status. Subsequently, the model guinea pigs were treated with XB and the cough frequency was observed by the capsaicin cough provocation test. The pathological changes of lung tissue were assessed by HE staining, and the levels of inflammatory mediators, mast cell degranulating substances, and neuropeptides were detected. The protein and mRNA expression of transient receptor potential vanilloid type 1(TRPV1), proteinase-activated receptor2(PAR2), and protein kinase C (PKC) were measured by Immunohistochemical staining, Western blot, and RT-qPCR. Changes in the abundance and composition of respiratory bacterial microbiota were determined by 16S rRNA sequencing.

RESULTS

After XB treatment, the model guinea pigs showed a dose-dependent decrease in cough frequency, along with a significant alleviation in inflammatory infiltration of lung tissue and a reduction in inflammatory mediators. In addition, XB high-dose treatment significantly decreased the levels of mast cell Tryptase as well as β-hexosaminidase (β-Hex) and downregulated the expression of TRPV1, PAR2, and p-PKC. Simultaneously, levels of neuropeptides like substance P (SP), calcitonin gene-related peptide (CGRP), neurokinin A (NKA), and nerve growth factor (NGF) were improved. Besides, XB also can modulate the structure of respiratory bacterial microbiota and restore homeostasis.

CONCLUSION

XB treatment alleviates cough hypersensitivity and inflammatory responses, inhibits the degranulation of mast cells, and ameliorates neurogenic inflammation in PIC guinea pigs whose mechanism may be associated with the inhibition of Tryptase/PAR2/PKC/TRPV1 and the recovery of respiratory bacterial microbiota.

Effectiveness and safety of Xingbei Zhike granules in patients with postinfectious cough: A multicenter, randomized, double-blinded, placebo-controlled trial

BACKGROUND

Postinfectious cough (PIC) is a common symptom following a respiratory tract infection. Xingbei Zhike (XBZK) granules, a Chinese patent medicine, has been widely used for PIC in clinics. However, there is a lack of evidence on the effectiveness.

PURPOSE

To investigate whether treatment with XBZK granules is effective for PIC.

STUDY DESIGN

A multicenter, randomized, double-blinded, placebo-controlled trial.

METHODS

Eligible participants from fourteen hospitals were randomly assigned in 3:1 ratio to receive either XBZK granules or placebo for 14 days. The primary outcome was the area under the curve (AUC) of a visual analogue scale (VAS) for cough symptoms. Secondary outcomes included cough symptom score (CSS), time and probability of recovery from cough, traditional Chinese medicine (TCM) syndrome score, relief rates of individual symptoms, Leicester Cough Questionnaire (LCQ) score, and the use of reliever drug.

RESULTS

A total of 235 patients (176 in XBZK and 59 in placebo groups) were included in the analysis. The AUC for cough VAS scores was lower in the XBZK than placebo group (-8.10, 95 % CI -14.12 to -2.07, p = 0.009), indicating superiority. XBZK decreased CSS (-0.68 points, 95 % CI -1.13 to -0.22, p = 0.01), shortened time to cough recovery (-2 days, hazard ratio [HR] 1.48, 95 % CI 1.03 to 2.13, p = 0.02), enhanced the probability of cough recovery (risk ratio [RR] 1.66, 95 % CI 1.07 to 2.58, p = 0.03), lowered TCM syndrome score (-0.99 points, 95 % CI -1.58 to -0.40, p = 0.004), increased the rate of daytime (RR 1.84, 95 % CI 1.07 to 3.15, p = 0.02) and nighttime (RR 2.07, 95 % CI 1.29 to 3.35, p = 0.004) cough recovery, and reduced the viscosity of sputum (RR 2.92, 95 % CI 1.66 to 5.13, p < 0.001) compared to placebo. There were no significant differences in LCQ scores and taking reliever drugs between groups. No severe adverse events were reported in either group.

CONCLUSIONS

XBZK granules are a promising therapy against PIC, effective in lowering the overall severity of cough, shortening the time to cough recovery, and reducing the viscosity of sputum.

Bacterial Etiology in Subacute Cough

Although postinfectious etiology is the most common cause of subacute cough, there are insufficient data on the epidemiology of associated bacterial infections. We aimed to identify the etiology of bacterial detection in subjects with subacute cough. A multicenter prospective observational study of 142 patients with postinfectious subacute cough was performed between August 2016 and December 2017 in Korea. We obtained 2 nasal swabs from each patient and used a multiplex bacterial polymerase chain reaction (PCR) kit that simultaneously detects Bordetella pertussis, Chlamydophila pneumoniae, Haemophilus influenzae, Legionella pneumophilia, Mycoplasma pneumoniae, and Streptococcus pneumoniae. About 29% (n = 41) of patients with subacute cough were positive for bacterial PCR in nasal swabs. The most common bacteria detected by bacterial PCR was H. influenzae (n = 19, 13.4%), followed by S. pneumoniae (n = 18, 12.7%), B. pertussis (n = 7, 4.9%), M. pneumoniae (n = 3, 2.1%), L. pneumophilia (n = 2, 1.4%), and C. pneumoniae (n = 1, 0.7%). Nine patients had dual positivity for the PCR. In conclusion, bacterial PCR was positive in the nasal swabs of about 29% of subjects with subacute cough, including 5% of positive PCR results for B. pertussis.

Cough Hypersensitivity Syndrome: Why Its Use Is Inappropriate in Children

In children and adults, chronic cough is a common symptom presenting to health professionals worldwide. It is internationally accepted that children with chronic cough should be managed with pediatric specific management guidelines. The newly proposed clinical entity of 'cough hypersensitivity syndrome' has gained significant attention in adult literature. Given the significant differences between childhood and adult chronic cough, including in respiratory physiology and anatomy, and cough sensitivity, we address the suitability of the use of cough hypersensitivity syndrome in children. We explore these differences between childhood and adult chronic cough, explain what cough hypersensitivity is and highlight why the term cough hypersensitivity syndrome should not be used in children.

Determinants of Post-COVID-19 Conditions among SARS-CoV-2-Infected Patients in Saudi Arabia: A Web-Based Cross-Sectional Study

Background: Large numbers of people infected with COVID-19 developed acute symptoms. Post-COVID-19 conditions have been reported after recovery or discharge from the hospital. However, little is known about the prevalence and possible risk factors of post-COVID-19 conditions in the Saudi community. Here, we describe the incidence of post-COVID-19 conditions among the general population of Saudi Arabia. Methods: We conducted a cross-sectional, nationwide study using an online survey in Saudi Arabia from 1 September 2021 to 28 February 2022. The survey was distributed using social media platforms, such as Twitter, WhatsApp, and Facebook. Patients with SARS-CoV-2 infection were included in the questionnaire adapted from published studies. Result: The study enrolled 7520 individuals who were previously infected with SARS-CoV-2. Most patients in our study were symptomatic and their acute symptoms may persist for more than six days. On the other hand, long-term complications may develop and continue for an extended period (post-COVID-19 conditions). Most of these complications are respiratory, neurological, psychological, or skin related. The proportion of long-term complications reported in this study is 36% among SARS-CoV-2-infected individuals. In addition, being female, old age, number of chronic complications, long-term medication, length of stay in hospital and intensive care unit, and duration of acute symptoms may be significant predictors of post-COVID-19 symptoms. Conclusion: In conclusion, the incidence of post-COVID-19 conditions among the Saudi population was high, which urges further investigation into the risk factors associated with post-COVID-19 symptoms.

PK/PD modeling links accelerated resolution of COVID‐19‐related clinical symptoms to SARS‐CoV‐2 viral load reduction in patients following treatment with Bamlanivimab alone or Bamlanivimab and Etesevimab together

The relationship between severe acute respiratory syndrome‐coronavirus 2 (SARS‐CoV‐2) viral load reduction and disease symptom resolution remains largely undefined for coronavirus disease 2019 (COVID‐19). While the vaccine‐derived immunity takes time to develop, neutralizing monoclonal antibodies offer immediate, passive immunity to patients with COVID‐19. Bamlanivimab and etesevimab are two potent neutralizing monoclonal antibodies directed to the receptor binding domain of the spike protein of SARS‐CoV‐2. This study aims to describe the relationship between viral load and resolution of eight common COVID‐19‐related symptoms in patients following treatment with neutralizing monoclonal antibodies (bamlanivimab alone or bamlanivimab and etesevimab together), in a phase II clinical trial. Corresponding pharmacokinetics (PKs), viral load, and COVID‐19‐related symptom data were modeled using Nonlinear Mixed Effects Modeling to describe the time‐course of eight COVID‐19‐related symptoms in an ordered categorical manner (none, mild, moderate, and severe), following administration of bamlanivimab or bamlanivimab and etesevimab together to participants with COVID‐19. The PK/pharmacodynamic (PD) models characterized the exposure‐viral load‐symptom time course of the eight preselected COVID‐19‐related symptoms. Baseline viral load (BVL), change in viral load from baseline, and time since the onset of symptoms, demonstrated statistically significant effects on symptom score probabilities. Higher BVL generally indicated an increased probability of symptom severity. The severity of symptoms decreased over time, partially driven by the decrease in viral load. The effect of increasing time resulting in decreased severity of symptoms was over and above the effect of decreasing viral load. Administration of bamlanivimab alone or together with etesevimab results in a faster time to resolution of COVID‐19‐related symptoms compared to placebo.

A History of Recurrent Episodes of Prolonged Cough as a Predictive Value for Determining Cough Variant Asthma in a Primary Care Setting

Background

Many patients visit primary care clinics with a complaint of cough. General practitioners (GPs) developed a list of the causative diseases of cough that can produce a patient's symptoms and signs. Then, the patients' medical histories were evaluated to determine whether the diagnosis of cough variant asthma (CVA) or post-infectious cough (PIC) could have been predicted.

Methods

We retrospectively investigated 195 outpatients with a complaint of cough. Medical histories of "recurrent episodes of prolonged cough" and "upper respiratory infection" were obtained during the initial visit. The accuracy of medical histories in predicting CVA and PIC was calculated on the area under the curve (AUC).

Results

Among eligible patients with cough, PIC was diagnosed in 99 patients (50.8%), CVA in 40 patients (20.5%), upper airway cough syndrome in 28 patients (14.4%), and chronic obstructive pulmonary disease in 11 patients (5.6%). Among the patients with CVA and those with PIC, 93% and 12%, respectively, had a history of recurrent episodes of prolonged cough. For the diagnosis of CVA, having a history of recurrent episodes of prolonged cough showed a moderately accurate AUC (0.76, 95% CI: 0.71-0.82). On the other hand, for the diagnosis of PIC, having no history of recurrent episodes of prolonged cough also showed a moderately accurate AUC (0.87, 95% CI: 0.82-0.92).

Conclusion

The medical history of recurrent episodes of prolonged cough is useful for the prediction of CVA as well as PIC.

Respiratory manifestations in the Ehlers-Danlos syndromes

Persons with the Ehlers-Danlos syndromes (EDS) report a wide range of respiratory symptoms, most commonly shortness of breath, exercise limitation, and cough. Also reported are noisy breathing attributed to asthma, difficulty with deep inhalation, and inspiratory thoracic pain. The literature consists of case reports and small cross-sectional and cohort studies. One case-control study estimated twofold to threefold greater respiratory disease burden among persons with EDS as compared to controls. The differential diagnosis for symptoms is broad. Structural alterations include pectus deformities, scoliosis, recurrent rib subluxations, and tracheobronchomalacia, associated with varying degrees of physiologic impairment. Those with vascular EDS have an increased risk of pneumothorax, intrapulmonary bleeding, cysts, and nonmalignant fibrous nodules. Functional aerodigestive manifestations such as inducible laryngeal obstruction may be misdiagnosed as asthma, with gastro-esophageal dysmotility and reflux as common contributing factors. Inflammatory manifestations include costochondritis, bronchiectasis, and localized respiratory allergic and nonallergic mast cell activation. Cranio-cervical instability can dysregulate respiratory control pathways. There is a need for careful phenotyping using standardized clinical tools and patient-reported outcomes and continuing collaboration with aerodigestive specialists including otolaryngologists and gastroenterologists. Also needed is further evaluation of respiratory symptoms in persons with hypermobility spectrum disorders. Personalized monitoring strategies are invaluable for interpretation and long-term management of respiratory symptoms.

WAO-ARIA consensus on chronic cough - Part II: Phenotypes and mechanisms of abnormal cough presentation - Updates in COVID-19

BACKGROUND

Chronic cough can be triggered by respiratory and non-respiratory tract illnesses originating mainly from the upper and lower airways, and the GI tract (ie, reflux). Recent findings suggest it can also be a prominent feature in obstructive sleep apnea (OSA), laryngeal hyperresponsiveness, and COVID-19. The classification of chronic cough is constantly updated but lacks clear definition. Epidemiological data on the prevalence of chronic cough are informative but highly variable. The underlying mechanism of chronic cough is a neurogenic inflammation of the cough reflex which becomes hypersensitive, thus the term hypersensitive cough reflex (HCR). A current challenge is to decipher how various infectious and inflammatory airway diseases and esophageal reflux, among others, modulate HCR.

OBJECTIVES

The World Allergy Organization/Allergic Rhinitis and its Impact on Asthma (WAO/ARIA) Joint Committee on Chronic Cough reviewed the current literature on classification, epidemiology, presenting features, and mechanistic pathways of chronic cough in airway- and reflux-related cough phenotypes, OSA, and COVID-19. The interplay of cough reflex sensitivity with other pathogenic mechanisms inherent to airway and reflux-related inflammatory conditions was also analyzed.

OUTCOMES

Currently, it is difficult to clearly ascertain true prevalence rates in epidemiological studies of chronic cough phenotypes. This is likely due to lack of standardized objective measures needed for cough classification and frequent coexistence of multi-organ cough origins. Notwithstanding, we emphasize the important role of HCR as a mechanistic trigger in airway- and reflux-related cough phenotypes. Other concomitant mechanisms can also modulate HCR, including type2/Th1/Th2 inflammation, presence or absence of deep inspiration-bronchoprotective reflex (lower airways), tissue remodeling, and likely cough plasticity, among others.

Characteristic appearance of the oropharynx in patients with postnasal drip (PND)-induced cough

INTRODUCTION

Post-nasal drip (PND)-induced cough is a common cause of chronic cough. However, there is little known about the characteristic physical findings of this condition.

OBJECTIVES

We investigated views of the pharyngeal wall in patients with PND-induced cough using a handy endoscopic images.

METHODS

The subjects were 135 consecutive patients referred to our hospital with a sensation of something "dripping down the throat" as one of their symptoms. Physical findings for the oropharynx were examined using Wi-Fi endoscope camera. The difference in probability of symptoms in patients with acute cough and those with subacute/chronic cough was assessed using a Bayesian Fisher exact test on a 2 × 2 table.

RESULTS

Among the patients, 105 (78%) complained of cough, 78 (58%) of acute cough, 20 (15%) of subacute cough, and 7 (5%) of chronic cough; and 71 (53%) had coexisting asthma. Using Bayesian inference, a sore or scratchy throat and fever were more common in patients with acute cough than in those with subacute/chronic cough. In endoscopic images of the oropharynx, a reddish curtain sign on the posterior pharyngeal wall behind the palatopharyngeal arch was found in 121 patients (90%).

CONCLUSION

Patients with acute PND-induced cough have a component of acute upper respiratory infection, because of high probability of a sore or scratchy throat and fever as symptom. A reddish curtain sign may be a useful finding for identifying PND-induced cough in these cases.

Fractional Exhaled Nitric Oxide (FeNO) Integrating Airway Hyperresponsiveness (AHR) Examination Promotes Etiologic Diagnosis and Treatment for Children with Chronic Cough

BACKGROUND Chronic cough is the main reason why parents seek medical treatment for their children. This study aimed to evaluate changes in airway function and inflammation levels and associated values in diagnosing and treating chronic cough. MATERIAL AND METHODS This study involved 118 children with chronic cough, including 45 cough-variant asthma (CVA) patients, 53 upper-airway cough syndrome (UACS) patients, and 20 post-infection cough (PIC) patients. Chronic cough was diagnosed as described by guidelines of the American College of Chest Physicians for evaluating chronic cough. Pulmonary ventilation function and airway hyperresponsiveness (AHR) were evaluated. Fractional exhaled nitric oxide (FeNO) levels and eosinophilic airway inflammation were measured. Eosinophil (EOS) count in sputum was also examined. CVA patients were treated with inhaled glucocorticoids, which have anti-inflammatory effects. RESULTS FeNO and sputum EOS levels were higher in CVA patients compared with UACS and PIC patients (P<0.05). CVA patients demonstrated significantly higher small airway indexes, including 25% forced expiratory flow (FEF), 50% FEF, and 75% FEF, compared with UACS and PIC patients (P<0.05). FeNO level was positively correlated with EOS in sputum (r=0.468, P=0.0001) and cough symptom scores (r=0.402, P<0.05). FeNO, EOS, and cough symptoms were significantly improved in CVA patients after glucocorticoid treatment. AHR was improved in all chronic cough patients after treatment. Cough-relief CVA patients demonstrated significantly higher FeNO levels compared with those without cough relief (P<0.05). CONCLUSIONS FeNO integrating pulmonary function and AHR examination can improve etiologic diagnosis and treatment for chronic cough in children.

Gender difference in the association between cough severity and quality of life among patients with postinfectious cough

Background

Despite close link exists between cough severity and quality of life (QoL), whether gender difference is implied in the effect of cough on QoL has not been studied yet. This study primarily aims to investigate whether the association between cough severity and QoL is modified by gender in patients with postinfectious cough.

Methods

Secondary analyses were performed in 180 participants with postinfectious cough in a multisite randomized controlled trial. Baseline demographics, clinical characteristics and score of cough specific quality of life questionnaire (CQLQ) were collected. Linear regression analyses were conducted to examine gender difference in CQLQ score and the association between cough severity and CQLQ score.

Results

Difference between women and men was not significant in CQLQ total score in the unadjusted analysis (P = 0.077). Women had a 2.20-point higher CQLQ total score than men (95% confidence interval (CI) 0.11–4.30; P = 0.039), after adjusting for age, cough duration, cough severity, and clinical center. Gender significantly modified the association between cough severity and CQLQ total score (coefficient 1.80, 95% CI 0.29–3.30; P = 0.020), after adjusting for age, cough duration, and study center. An increase of 1-point in cough severity was associated with a 2.55-point (95% CI 1.16–3.95) increase in CQLQ total score in women versus a 1.26-point (95% CI 0.20–2.31) increase in men (P = 0.020).

Conclusions

Female sex may be associated with worse QoL than men, and women’s QoL may be more significantly impaired as cough symptom deteriorates. Gender difference should be taken into account in the clinical settings and research of cough and cough related QoL.

Trial registration: Chinese Clinical Trial Registry, ChiCTRTRC12002297. Registered 19 June 2012, http://www.chictr.org.cn/abouten.aspx.

Approach to the Patient with Cough

Cough is a common presenting symptom for patients in a primary care setting. Chronic cough is defined as a cough lasting for more than 8 weeks. The most common causes of chronic cough are upper airway cough syndrome, asthma, and gastroesophageal reflux disease. Detailed history and physical examination are critical in identifying potential etiologies of cough. When there is no prevailing diagnosis, step-wise empiric trial of medication is a strategic and cost-effective approach. Certain features of chronic cough should provoke an expedited and invasive diagnostic strategy. Effectively treating patients with chronic cough has a high impact on quality of life.

Oral corticosteroids for post-infectious cough in adults: study protocol for a double-blind randomized placebo-controlled trial in Swiss family practices (OSPIC trial)

BACKGROUND

Cough is a common reason for patients to visit general practices. So-called post-infectious cough is defined as lasting 3 to 8 weeks after an upper respiratory tract infection. It can be disabling in daily activities, with substantial impact on physical and psychosocial health, leading to impaired quality of life and increased health care costs. Recommendations for the management of post-infectious cough in primary care are scarce and incoherent. A systematic review and meta-analysis of randomized clinical trials (RCT) assessing patient-relevant benefits and potential harms of available treatments identified six eligible RCTs assessing different treatment regimens (i.e. inhaled fluticasone propionate, inhaled budesonide, salbutamol plus ipratropium-bromide, montelukast, nociception-opioid-1-receptor agonist, codeine, gelatine). No RCT found clear patient-relevant benefits and most had an unclear or high risk of bias. Post-infectious cough is thought to be mediated by inflammatory processes that are also present in exacerbations of asthma or chronic obstructive pulmonary diseases for which there is strong evidence that oral corticosteroids provide patient-relevant benefit without relevant harm. We therefore plan to conduct the first RCT evaluating the effectiveness of oral corticosteroids for post-infectious cough.

METHODS

We are conducting a triple-blinded randomized-controlled and multicentred superiority trial in primary health care practices in Switzerland. We will include 204 adult patients who consult their general practitioner (GP) for a cough lasting 3 to 8 weeks following an upper respiratory tract infection. Participants will be randomly allocated to either the 5-day treatment with oral corticosteroids or placebo. The primary outcome is cough-related quality of life assessed by the Leicester Cough Questionnaire score 14 days after randomization. Secondary outcomes include cough-related quality of life at several time points, overall cessation of cough and adverse events.

DISCUSSION

This RCT will provide evidence on whether oral corticosteroids are beneficial and safe in patients with post-infectious cough. Results can have a substantial impact on the well-being and management of these patients in Switzerland and beyond. An evidence-based treatment for this condition may reduce re-consultations with GPs and spending for antitussive drugs, thus possibly having an impact on health care spending.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04232449 . Prospectively registered on 18 January 2020.

Zhisou powder in treatment of postinfectious cough: A protocol for systematic review and meta-analysis

BACKGROUND

The pathogensis of postinfectious cough (PIC) is unkown, unsatisfactory clinical curative effects of conventional western medicine have been shown. Zhisou powder (ZP) is one of the most common prescriptions in traditional Chinese medicine for the treatment of PIC. However, the effects and safety also remain uncertain. We aim to systematically review the effectiveness and safety of ZP for PIC.

METHODS

We will search the following databases: PubMed, Embase, Cochrane Library, MEDLINE, the China National Knowledge Infrastructure , the Chinese Biomedical Literature Database, Cqvip Database, and Wanfang Data. The studies published from the inception of the database to May 2020 will be retrieved. The randomized controlled trials on ZP for PIC will be included. The primary outcomes were cough relief rate and cough resolution rate. We will perform the analyses using RevMan V.5.3 software.

RESULTS

This study will provide high-quality evidence of ZP for PIC in the effectiveness and safety.

CONCLUSIONS

This systematic review will assess whether ZP is an effective and safe prescription for PIC.

Rhinovirus-16 increases ATP release in A549 cells without concomitant increase in production

Human rhinovirus (RV) is the most common cause of upper respiratory tract infection (URTI) and chronic airway disease exacerbation. Cough is present in 50–80% of URTI cases, accompanied by heightened airway hypersensitivity, yet no effective treatment currently exists for this infectious cough. The mechanism by which RV causes cough and airway hypersensitivity in URTI is still unknown despite recent advances in potential therapies for chronic cough.

The effect of RV-16 infection (MOI 1) on intracellular ATP stores and ATP release in A549 alveolar epithelial cells was measured.

RV-16 infection was found to significantly increase (by 50% from basal at 24 h) followed by decrease (by 50% from basal at 48 and 72 h) intracellular ATP concentrations, while increasing ATP release (from 72 h) independently of secondary stimulation. This effect was mimicked by intercellular adhesion molecule 1 receptor binding alone through ultraviolet-inactivated sham control. In addition, RV-16-infected cells became more sensitive to secondary stimulation with both hypotonic and isotonic solutions, suggestive of a hypersensitive response. These responses were not mediated via increased TRPV4 or pannexin-1 whole-cell expression as determined by Western blotting. Interestingly, the increased ATP release seen was not a result of increased mitochondrial ATP production.

Thus, this is the first report demonstrating that RV-16 infection of airway epithelial cells causes hypersensitivity by increasing ATP release. These finding provide a novel insight into the process by which viruses may cause cough and identify a potential target for treatment of viral and post-viral cough.

Rhinovirus-infected airway epithelial cells (A549) show increased ATP release with and without a secondary stimulation (mechanical or hypotonic), which may account for increased cough sensitivity seen during respiratory viral infectionshttps://bit.ly/3eABEY9

Effect of Qinbai Qingfei Concentrated Pellets on substance P and neutral endopeptidase of rats with post-infectious cough

Background

In recent years, it has been reported that Qinbai Qingfei Concentrated Pellet (QQCP) has the effect of relieving cough and reducing sputum. However, the therapeutic potentials of QQCP on post-infectious cough (PIC) rat models has not been elucidated. So the current study was aimed to scientifically validate the efficacy of QQCP in post infectious cough.

Methods

All rats were exposed to sawdust and cigarette smokes for 10 days, and intratracheal lipopolysaccharide (LPS) and capsaicin aerosols. Rats were treated with QQCP at dose of 80, 160, 320 mg/kg. Cough frequency was monitored twice a day for 10 days after drug administration. Inflammatory cell infiltration was determined by ELISA. Meanwhile, the histopathology of lung tissue and bronchus in rats were evaluated by hematoxylin-eosin staining (H&E). Neurogenetic inflammation were measured by ELISA and qRT-PCR.

Results

QQCP dose-dependently decreased the cough frequency and the release of pro-inflammatory cytokines TNF-α, IL-1β, IL-6 and IL-8, but exerted the opposite effects on the secretion of anti-inflammatory cytokines IL-10 and IL-13 in BALF and serum of PIC rats. The oxidative burden was effectively ameliorated in QQCP-treated PIC rats as there were declines in Malondialdehyde (MDA) content and increases in Superoxide dismutase (SOD) activity in the serum and lung tissue. In addition, QQCP blocked inflammatory cell infiltration into the lung as evidenced by the reduced number of total leukocytes and the portion of neutrophils in the broncho - alveolar lavage fluid (BALF) as well as the alleviated lung damage. Furthermore, QQCP considerable reversed the neurogenetic inflammation caused by PIC through elevating neutral endopeptidase (NEP) activity and reducing Substance P (SP) and Calcitonin gene related peptide (CGRP) expression in BALF, serum and lung tissue.

Conclusions

Our study indicated that QQCP demonstrated a protective role of PIC and may be a potential therapeutic target of PIC.

Cough Radiculopathy: Postinfectious Cough-Related Acute Lumbar Radiculopathy

Cough is a protective reflex of airways and lungs. Cough may result in several complications. Postinfectious cough is a cough that begins during an acute respiratory tract infection, usually is self-limited, and is due to airway hyperresponsiveness as a result of airway inflammation. Cough radiculopathy has been once reported by Torrington and Adornato in the form of acute cervical radiculopathy. This is a case of acute lumbar radiculopathy as a result of postinfectious cough. Literature review did not show a similar case.

Clinical predictors and timing of cessation of viral RNA shedding in patients with COVID-19

BACKGROUND

Molecular detection of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is key in the diagnosis of coronavirus disease 2019 (COVID-19) and has been widely used for followup of cases as a proxy for contagiousness. The persistence of SARS-CoV-2 RNA shedding in the context of clinical features and comorbidities is understudied.

METHODS

We retrospectively reviewed laboratory-confirmed COVID-19 adult symptomatic cases at Mayo Clinic, eventually achieving cessation of viral RNA shedding (CVS), defined as two consecutive negative SARS-CoV-2 PCR results on nasopharyngeal swabs collected at least 24 h apart.

RESULTS

A total of 251 patients were included, median age was 53 years and 59 % female. The most common symptoms at diagnosis were cough, myalgia, dyspnea, fever and chills. Myalgia, cough, anosmia, ageusia and sore throat were common at CVS, but fever and dyspnea were not observed. The median time from symptom onset to CVS was 23 days, and did not differ by symptoms. The weekly cumulative CVS rate was 2, 14, 44, 73, 91 and 95 % at 1-6 weeks from symptom onset, respectively. Cough and fever were associated with a positive PCR test if tested within 2 weeks of symptoms (P < 0.05). Patients with asthma or immunosuppression were less likely to achieve CVS if tested 3 weeks into symptoms (P < 0.04).

CONCLUSIONS

The cumulative CVS rate at 3 weeks from symptom-onset is 44 % in our entire cohort. The findings of our study highlight the low yield of repeating a SARS-CoV-2 NP PCR test within 21 days of a laboratoryconfirmed COVID-19 diagnosis.

Efficacy and safety of Zihua Wenfei granules in treatment of postinfectious cough (wind-cold invading lungs syndrome): study protocol for a randomized controlled trial

Background

Postinfectious cough usually develops and persists following respiratory tract infection. The protracted cough is embarrassing and troublesome and significantly impairs daily life. However, the optimal treatment available for this condition is still not known. This study aims to investigate the efficacy and safety of a new Chinese herbal prescription, Zihua Wenfei granule (ZHWFG), in treatment of postinfectious cough (wind-cold invading lungs syndrome).

Methods

This study is a prospective, multi-center, randomized, double-blinded, parallel group, placebo-controlled trial. A total of 216 adult participants with postinfectious cough will be enrolled from six study centers across China. All participants are randomly allocated to one of three parallel treatment groups: (1) 15 g of active ZHWFG three times daily, (2) 10 g of active ZHWFG plus 5 g of ZHWFG-matched placebo three times daily, and (3) 15 g of ZHWFG-matched placebo three times daily. The treatment duration is 14 consecutive days. The primary outcomes are cough resolution rate and cough relief rate. Secondary outcomes include time to cough resolution, time to cough relief, change from baseline in cough symptom score, cough visual analog scale value, traditional Chinese medicine syndrome score at days 7 and 14, and change of CQLQ from baseline to post-treatment as well as adverse events.

Discussion

This trial may not only investigate the efficacy and safety of ZHWFG in the management of postinfectious cough (wind-cold invading lungs syndrome), but also add the evidence of Chinese herbal medicine in treatment of postinfectious cough and provide an alternative option for the management of postinfectious cough.

Trial registration

ChiCTR1900022078. Registered on 23 March 2019. http://www.chictr.org.cn/showproj.aspx?proj=36547.

Diagnoses and management of adult cough: An Indian Environmental Medical Association (EMA) position paper

BACKGROUND

Cough is a common yet distressing symptom that results in significant health care costs from outpatient visits and related consultations.

OBJECTIVE

The understanding of the pathobiology of cough in recent times has undergone an evolution with Cough hypersensitivity syndrome (CHS) being suggested in most cases of dry cough. However, in the case of productive cough, ancillary mechanisms including impaired Mucociliary clearance, in addition to hypermucosecretory bronchospastic conditions of Smoker's cough, asthma-COPD overlap, bronchiectasis, and allergic bronchopulmonary aspergillosis, need to be critically addressed while optimizing patient care with symptomatic therapy in outpatient settings of India.

METHODS

In this review, evidence-based graded recommendations on use of antitussives - & protussives as a Position Paper were developed based on the Level and Quality of Scientific evidence as per Agency for Health Care and Quality (AHRQ) criteria listing and Expert opinions offered by a multidisciplinary EMA panel in India.

RESULTS

Management of acute or chronic cough involves addressing common issues of environmental exposures and patient concerns before instituting supportive therapy with antitussives or bronchodilatory cough formulations containing mucoactives, anti-inflammatory, or short-acting beta-2 agonist agents.

CONCLUSION

The analyses provides a real world approach to the management of acute or chronic cough in various clinical conditions with pro- or antitussive agents while avoiding their misuse in empirical settings.

Tuberculosis in people with rheumatic disease in Finland 1995-2007: a nationwide retrospective register study

Objectives

RA and its medication, especially TNF-α inhibitors, increase the risk of clinical tuberculosis (TB) infection. We aimed to investigate the clinical manifestations, incidence and temporal changes in TB occurring concurrently with rheumatic diseases (RDs) between 1995 and 2007.

Methods

We combined the register of the Social Insurance Institution of Finland and the National Infectious Disease Register to find adult patients with reimbursed DMARDs and with a TB notification between 1995 and 2007. After reviewing the medical records, we described their clinical manifestations and medications, explored TB incidence trends using Poisson regression, and compared the incidence of TB with that of the general population.

Results

We identified 291 patients with both TB and rheumatic disease (RD), 196 of whom had RA. Between 1995 and 2007, the incidence of TB in adult RD decreased from 58.8 to 30.0 per 100 000 (trend P < 0.001, average marginal effect -3.4/100 000 per year, 95% CI -4.4, -2.4). Compared with the general population, the incidence was ∼4-fold. Among RD patients, pulmonary TB was the most common form of TB (72.6%). Disseminated TB was present in 56 (19.6%) patients.

Conclusion

The incidence of TB among RD patients was ∼4-fold that of the general population, and it declined between 1995 and 2007. Disseminated TB was present in nearly 20% of patients.

HSP90 inhibitor geldanamycin reverts IL-13- and IL-17-induced airway goblet cell metaplasia

Goblet cell metaplasia, a disabling hallmark of chronic lung disease, lacks curative treatments at present. To identify novel therapeutic targets for goblet cell metaplasia, we studied the transcriptional response profile of IL-13-exposed primary human airway epithelia in vitro and asthmatic airway epithelia in vivo. A perturbation-response profile connectivity approach identified geldanamycin, an inhibitor of heat shock protein 90 (HSP90) as a candidate therapeutic target. Our experiments confirmed that geldanamycin and other HSP90 inhibitors prevented IL-13-induced goblet cell metaplasia in vitro and in vivo. Geldanamycin also reverted established goblet cell metaplasia. Geldanamycin did not induce goblet cell death, nor did it solely block mucin synthesis or IL-13 receptor-proximal signaling. Geldanamycin affected the transcriptome of airway cells when exposed to IL-13, but not when exposed to vehicle. We hypothesized that the mechanism of action probably involves TGF-β, ERBB, or EHF, which would predict that geldanamycin would also revert IL-17-induced goblet cell metaplasia, a prediction confirmed by our experiments. Our findings suggest that persistent airway goblet cell metaplasia requires HSP90 activity and that HSP90 inhibitors will revert goblet cell metaplasia, despite active upstream inflammatory signaling. Moreover, HSP90 inhibitors may be a therapeutic option for airway diseases with goblet cell metaplasia of unknown mechanism.

Clinically Diagnosing Pertussis-associated Cough in Adults and Children: CHEST Guideline and Expert Panel Report

BACKGROUND

The decision to treat a suspected case of pertussis with antibiotics is usually based on a clinical diagnosis rather than waiting for laboratory confirmation. The current guideline focuses on making the clinical diagnosis of pertussis-associated cough in adults and children.

METHODS

The American College of Chest Physicians (CHEST) methodologic guidelines and the Grading of Recommendations, Assessment, Development, and Evaluation framework were used. The Expert Cough Panel based their recommendations on findings from a systematic review that was recently published on the topic; final grading was reached by consensus according to Delphi methodology. The systematic review was carried out to answer the Key Clinical Question: In patients presenting with cough, how can we most accurately diagnose from clinical features alone those who have pertussis-associated cough as opposed to other causes of cough?

RESULTS

In adults, after pre-specified meta-analysis exclusions, pooled estimates of sensitivity and specificity were generated for only 4 clinical features: paroxysmal cough, post-tussive vomiting, inspiratory whooping, and absence of fever. Both paroxysmal cough and absence of fever had high sensitivity (93.2% [95% CI, 83.2-97.4] and 81.8% [95% CI, 72.2-88.7], respectively) and low specificity (20.6% [95% CI, 14.7-28.1] and 18.8% [95% CI, 8.1-37.9]). Inspiratory whooping and posttussive vomiting had a low sensitivity (32.5% [95% CI, 24.5-41.6] and 29.8% [95% CI, 18.0-45.2]) but high specificity (77.7% [95% CI, 73.1-81.7] and 79.5% [95% CI, 69.4-86.9]). In children, after pre-specified meta-analysis exclusions, pooled estimates of sensitivity and specificity were generated for only 1 clinical feature in children (0-18 years): posttussive vomiting. Posttussive vomiting in children was only moderately sensitive (60.0% [95% CI, 40.3-77.0]) and specific (66.0% [95% CI, 52.5-77.3]).

CONCLUSIONS

In adults with acute (< 3 weeks) or subacute (3-8 weeks) cough, the presence of whooping or posttussive vomiting should rule in a possible diagnosis of pertussis, whereas the lack of a paroxysmal cough or the presence of fever should rule it out. In children with acute (< 4 weeks) cough, posttussive vomiting is suggestive of pertussis but is much less helpful as a clinical diagnostic test. Guideline suggestions are made based upon these findings and conclusions.

Performance of the new clinical case definitions of pertussis in pertussis suspected infection and other diagnoses similar to pertussis

Background

In an effort to improve the pertussis diagnosis, the Global Pertussis Initiative (GPI) proposed an algorithm of the signs/symptoms of pertussis for three age groups: 0–3 months, 4 months to 9 years, and ≥10 years of age.

Methods

We evaluated the accuracy of the clinical case definitions for pertussis proposed by the GPI using laboratory-confirmed pertussis as a reference standard for four groups: clinically suspected pertussis without comorbidity; asthma exacerbation; allergic constitution, and other diagnoses (bronchitis, bronchiolitis, laryngitis, and tracheitis). We included only patients who fulfilled one or more criteria of clinical case definitions for the age groups (0–3 months, 4 months–9 years, and ≥10 years of age).

The data for this prospective epidemiological study were collected between 1^st January 2013–31^st December 2016 at the outpatients and inpatients health care settings in the South Bačka District of Autonomous Province of Vojvodina, Serbia. We evaluated accuracy of the certain sign and symptom combinations of GPI case definitions based on their sensitivity, specificity, and likelihood ratios.

Results

A total of 1043 participants were included, with 306 (29.3%) laboratory-confirmed pertussis cases. In patients aged 0–3 months, whoop and apnoea associated with laboratory confirmation of pertussis. In patients aged 4 months-9 years with a pertussis suspicion infection or with one of the other diagnoses, the highest accuracy was found for whoop combined with apnoea or post-tussive emesis. In patients aged 10 years and older, several different sign and symptom combinations were associated with an increased risk of pertussis among all enrolment diagnoses. There were fewer hospitalizations among the fully vaccinated children than in partly or unvaccinated children aged 4 months to 6 years (20.7% vs. 60.0%, p = 0.017).

Conclusions

The numerous sign and symptom combinations in the observed case definitions were good predictors for laboratory-confirmed pertussis among all enrolment diagnoses, therefore suggesting the necessity for increased awareness of possibility for pertussis in patients with certain pertussis-like medical conditions.

Treatments for subacute cough in primary care: systematic review and meta-analyses of randomised clinical trials

BACKGROUND

Subacute cough following a non-specific viral infection lasting 3-8 weeks is common. However, despite many treatment options there are no systematic reviews evaluating these.

AIM

To provide a systematic overview of treatment options and outcomes evaluated in randomised clinical trials (RCTs).

DESIGN AND SETTING

Systematic review and meta-analyses assessing the overall effects of any treatment for subacute cough.

METHOD

The authors systematically searched PubMed/MEDLINE and the Cochrane Central Register of Controlled Trials (last search March 2017) for RCTs in adult patients with subacute cough. The authors considered trials evaluating any outcome of any drug or non-drug treatments, apart from traditional Chinese and Asian medicines. They combined treatment effects on cough-related outcomes in random effects meta-analyses.

RESULTS

Six eligible RCTs including 724 patients were identified. These assessed montelukast, salbutamol plus ipratropium bromide, gelatine, fluticasone propionate, budesonide, and nociception opioid 1 receptor agonist and codeine. Five studies reported effects on various cough severity scores at various timepoints. No treatment option was associated with a clear benefit on cough recovery or other patient-relevant outcomes in any of the studies or in meta-analyses for cough outcomes at 14 days and 28 days. Reported adverse events were rather mild and reported for 14% of patients across all treatments.

CONCLUSION

Evidence on treatment options for subacute cough is weak. There is no treatment showing clear patient-relevant benefits in clinical trials.

Honey for acute cough in children

BACKGROUND

Cough causes concern for parents and is a major cause of outpatient visits. Cough can impact quality of life, cause anxiety, and affect sleep in children and their parents. Honey has been used to alleviate cough symptoms. This is an update of reviews previously published in 2014, 2012, and 2010.

OBJECTIVES

To evaluate the effectiveness of honey for acute cough in children in ambulatory settings.

SEARCH METHODS

We searched CENTRAL (2018, Issue 2), which includes the Cochrane Acute Respiratory Infections Group's Specialised Register, MEDLINE (2014 to 8 February 2018), Embase (2014 to 8 February 2018), CINAHL (2014 to 8 February 2018), EBSCO (2014 to 8 February 2018), Web of Science (2014 to 8 February 2018), and LILACS (2014 to 8 February 2018). We also searched ClinicalTrials.gov and the World Health Organization International Clinical Trial Registry Platform (WHO ICTRP) on 12 February 2018. The 2014 review included searches of AMED and CAB Abstracts, but these were not searched for this update due to lack of institutional access.

SELECTION CRITERIA

Randomised controlled trials comparing honey alone, or in combination with antibiotics, versus no treatment, placebo, honey-based cough syrup, or other over-the-counter cough medications for children aged 12 months to 18 years for acute cough in ambulatory settings.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included six randomised controlled trials involving 899 children; we added three studies (331 children) in this update.We assessed two studies as at high risk of performance and detection bias; three studies as at unclear risk of attrition bias; and three studies as at unclear risk of other bias.Studies compared honey with dextromethorphan, diphenhydramine, salbutamol, bromelin (an enzyme from the Bromeliaceae (pineapple) family), no treatment, and placebo. Five studies used 7-point Likert scales to measure symptomatic relief of cough; one used an unclear 5-point scale. In all studies, low score indicated better cough symptom relief.Using a 7-point Likert scale, honey probably reduces cough frequency better than no treatment or placebo (no treatment: mean difference (MD) -1.05, 95% confidence interval (CI) -1.48 to -0.62; I² = 0%; 2 studies; 154 children; moderate-certainty evidence; placebo: MD -1.62, 95% CI -3.02 to -0.22; I² = 0%; 2 studies; 402 children; moderate-certainty evidence). Honey may have a similar effect as dextromethorphan in reducing cough frequency (MD -0.07, 95% CI -1.07 to 0.94; I² = 87%; 2 studies; 149 children; low-certainty evidence). Honey may be better than diphenhydramine in reducing cough frequency (MD -0.57, 95% CI -0.90 to -0.24; 1 study; 80 children; low-certainty evidence).Giving honey for up to three days is probably more effective in relieving cough symptoms compared with placebo or salbutamol. Beyond three days honey probably had no advantage over salbutamol or placebo in reducing cough severity, bothersome cough, and impact of cough on sleep for parents and children (moderate-certainty evidence). With a 5-point cough scale, there was probably little or no difference between the effects of honey and bromelin mixed with honey in reducing cough frequency and severity.Adverse events included nervousness, insomnia, and hyperactivity, experienced by seven children (9.3%) treated with honey and two children (2.7%) treated with dextromethorphan (risk ratio (RR) 2.94, 95% Cl 0.74 to 11.71; I² = 0%; 2 studies; 149 children; low-certainty evidence). Three children (7.5%) in the diphenhydramine group experienced somnolence (RR 0.14, 95% Cl 0.01 to 2.68; 1 study; 80 children; low-certainty evidence). When honey was compared with placebo, 34 children (12%) in the honey group and 13 (11%) in the placebo group complained of gastrointestinal symptoms (RR 1.91, 95% CI 1.12 to 3.24; I² = 0%; 2 studies; 402 children; moderate-certainty evidence). Four children who received salbutamol had rashes compared to one child in the honey group (RR 0.19, 95% CI 0.02 to 1.63; 1 study; 100 children; moderate-certainty evidence). No adverse events were reported in the no-treatment group.

AUTHORS' CONCLUSIONS

Honey probably relieves cough symptoms to a greater extent than no treatment, diphenhydramine, and placebo, but may make little or no difference compared to dextromethorphan. Honey probably reduces cough duration better than placebo and salbutamol. There was no strong evidence for or against using honey. Most of the children received treatment for one night, which is a limitation to the results of this review. There was no difference in occurrence of adverse events between the honey and control arms.

Clinical Effects and Safety of Zhi Sou San for Cough: A Meta-Analysis of Randomized Trials

Introduction

Zhi Sou San (ZSS), a traditional Chinese prescription, has been widely applied in treating cough. The purpose of this meta-analysis was to evaluate the effectiveness and safety of ZSS for cough.

Methods

We searched relevant articles up to 5 March 2017 in seven electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PubMed, Chinese National Knowledge Infrastructure (CNKI), Cqvip Database (VIP), China Biology Medicine disc (CBM), and Wanfang Data. Randomized controlled trials (RCTs) were eligible, regardless of blinding. The primary outcome was the total effective rate.

Results

Forty-six RCTs with a total of 4007 participants were identified. Compared with western medicine, ZSS significantly improved the total effective rate (OR: 4.45; 95% CI: 3.62–5.47) and the pulmonary function in terms of FEV1 (OR: 0.35; 95% CI: 0.24–0.46) and decreased the adverse reactions (OR: 0.05; 95% CI: 0.02–0.01) and the recurrence rate (OR: 0.30; 95% CI: 0.16–0.57). However, there was no significant improvement in the cough symptom score comparing ZSS with western medicine.

Conclusions

This meta-analysis shows that ZSS has significant additional benefits and relative safety in treating cough. However, more rigorously designed investigations and studies, with large sample sizes, are needed because of the methodological flaws and low quality of the included trials in this meta-analysis.

Minimal Clinically Important Differences (MCIDs) of the Thai Version of the Leicester Cough Questionnaire for Subacute and Chronic Cough

OBJECTIVES

To investigate the minimal clinically important differences (MCIDs) of the Thai version of the Leicester Cough Questionnaire (LCQ-T) in patients with subacute and chronic cough.

METHODS

Patients with cough for 3 or more weeks were recruited from outpatient clinics. They self-completed the LCQ-T at an initial evaluation and repeated the LCQ-T with a Global Rating of Change scale at follow-up. For the anchor-based method, the MCID was defined as a change in the LCQ scores that corresponded to the smallest improvement in Global Rating of Change score (+2 to +3). For distribution-based methods, the MCIDs were estimated from the standard error of measurement and a half and one-third of the SD of the LCQ score changes from baseline to follow-up.

RESULTS

A total of 107 patients were included. The causes of cough were postinfectious cough/bronchitis (35.5%), asthma (20.6%), rhinosinusitis (16.8%), bronchiectasis (17.8%), and chronic obstructive pulmonary disease (9.3%). The anchor-based method yielded MCIDs of 1.1, 0.4, 0.4, and 0.4 for the total, physical, psychological, and social domains, respectively. The distribution-based method using standard error qof measurement yielded MCIDs of 0.8, 0.3, 0.3, and 0.3, whereas those using a half SD yielded MCIDs of 2.0, 0.6, 0.8, and 0.8 and those using one-third SD yielded MCIDs of 1.4, 0.4, 0.5, and 0.5 for the total, physical, psychological, and social domains, respectively.

CONCLUSIONS

The MCIDs of the LCQ-T for subacute and chronic cough are 1.1, 0.4, 0.4, and 0.4 for the total, physical, psychological, and social domains, respectively. These estimates should be useful in making meaningful interpretations of the changes in quality of life because of cough.

Phenotypic presentation of chronic cough in children

Chronic cough in children is increasingly defined as a cough that lasts more than four weeks. It is recognized as a different entity than cough in adults. As a result, the diagnostic approach and management of chronic cough in children are no longer extrapolated from adult guidelines. These differences are attributed to the various characteristics of the respiratory tract, immunological system and nervous system in children. Specific paediatric guidelines and algorithms for chronic cough are now widely applied. Post-infectious cough, asthma, bronchiectasis, malacia and protracted bacterial bronchitis (PBB) appear to be the major causes of cough in young children. By adolescence, the causes of cough are more likely to be similar to those in adults, namely, gastroesophageal reflux, asthma, and upper airway syndrome. In a primary setting, it is essential to investigate the underlying disease entity that initiates and sustains chronic cough. The use of cough management protocols or algorithms improves clinical outcomes and should differ depending on the associated characteristics of the cough and the child's clinical history. Performing a thorough history and physical examination is crucial to starting an individualised approach. A correct interpretation of the phenotypic presentation can be translated into guidance for workup. This approach will be helpful for adequate management without the risk of inappropriate investigations or inadequate treatment.

Association between fractional exhaled nitric oxide and clinical characteristics and outcomes in patients with subacute cough

OBJECTIVES

To investigate the relationships between fractional exhaled nitric oxide (FENO) and clinical characteristics and outcomes in patients with subacute cough.

METHODS

Patients with subacute cough (n = 189) after upper respiratory tract infection were enrolled in this single-center prospective study, and were divided into low-FENO (<25 ppb) and high-FENO groups (≥25 ppb). Empirical therapies (without inhaled or systemic corticosteroids) were prescribed based on clinical experience and follow-up until the disease course reached 8 weeks. FENO values, cough symptom scores (CSS), and Leicester Cough Questionnaire (LCQ) scores were obtained, analyzed, and compared between two groups of patients.

RESULTS

The low-FENO and high-FENO groups comprised 136 and 53 patients, respectively. The multiple regression analysis showed that blood eosinophil count and gender were independent factors for elevated FENO (β = 1.38, 0.25, respectively). LCQ scores, total CSS, and daytime CSS were comparable between the low-FENO and high-FENO groups. The nighttime CSS of the high-FENO group were significantly higher than that of the low-FENO group (P = .03). The CSS and LCQ score were improved in both groups but were comparable between groups after 10 days treatment.

CONCLUSIONS

Patients with subacute cough and high-FENO levels have more severe nocturnal cough than those of patients with low-FENO levels. However, FENO levels do not appear to correlate with the clinical outcomes or treatment response. The significance of FENO in the management of subacute cough needs to be further evaluated, at least in the current empirical treatment without corticosteroids.

Underdetection and underreporting of pertussis in children attended in primary health care centers: Do surveillance systems require improvement?

BACKGROUND

Pertussis is an underestimated disease. Several European countries have developed models to account for underreporting of pertussis. The aim of this study was to estimate pertussis underdetection and underreporting in pediatric patients attending primary health care centers (PHCCs).

METHODS

We reviewed clinical records of PHCCs in Barcelona in 2012. Factors associated with underdetection and underreporting were analyzed by logistic regression. Adjusted odds ratios (aORs) and 95% confidence intervals (95% CIs) were calculated.

RESULTS

We included 3,505 children aged < 7 years (mean age, 34  ±  20.7 months; range, 0-82 months) presenting with cough; 9.3% (326 out of 3,505) of patients also had ≥ 1 symptoms related to pertussis accompanied by cough for a duration ≥ 2 weeks. Of the 326 children receiving clinical criteria, only 31 (9.5%) were laboratory-confirmed and 6 (1.8%) were detected but not reported. There were 295 (90.5%) undetected suspected pertussis cases. Age ≥ 18 months (aOR, 8.51; 95% CI, 1.82-39.86), cyanosis (aOR, 6.71; 95% CI, 1.43-31.39), request for chest radiograph (aOR, 0.26; 95% CI, 0.07-0.99), and request for other laboratory tests (aOR, 5.39; 95% CI, 2.19-13.27) were associated with underdetection. Paroxysmal cough (aOR, 5.77; 95% CI, 1.05-31.76) and request for other laboratory tests (aOR, 2.91; 95% CI, 1.11-7.62) were associated with underreporting.

CONCLUSIONS

Both underdetection and underreporting complicate the understanding of pertussis epidemiology. Correct assessment of pertussis symptoms and notification of cases must be improved to control pertussis.

Curative Effects of Suhuang Zhike Capsule on Postinfectious Cough: A Meta-Analysis of Randomized Trials

Objective. In this paper, we intended to systematically evaluate the efficacy of Suhuang Zhike Capsule (SZC) on postinfectious cough (PIC) in adults (age > 18). Methods. MEDLINE (PubMed), Chinese National Knowledge Infrastructure (CNKI), Cqvip Database (VIP), and Wanfang Database were researched for the randomized controlled trials (RCTs) of SZC for PIC. The search was limited to human studies, using the search keywords or free-text terms “cough,” “post-infectious cough,” “postinfectious cough,” “post-cold cough,” “postviral cough,” “postcold cough,” “Suhuang Zhike capsule,” “Chinese Medicine,” and “randomized clinical trials”. Two reviewers individually extracted data from the included RCTs and then the extracted data were analyzed using Review Manager 5.3 software. Results. Seven RCTs involving 573 patients entered the inclusion criteria. Findings suggested that, compared with western conventional medicine (WCM) and other Chinese medicine, SZC could effectively improve the efficacy rate (OR 2.68, 95%  CI, 1.48–4.84, P = 0.001; OR 4.86, 95%  CI, 1.50–15.73, P = 0.008, separately). Moreover, SZC could also improve the efficacy rate of Chinese medicine symptom (MD −0.74, 95%  CI, −1.46~−0.02, P = 0.04). However, in terms of cough relief time, more evidence is needed to prove that SZC have an earlier antitussive effect (MD −1.31, 95%  CI, −3.06~0.45, P = 0.14). Conclusion. The current evidence shows that SZC is effective in the treatment of PIC in adults and can significantly improve the effective rate of Chinese medicine symptoms.

Parainfluenza 3-Induced Cough Hypersensitivity in the Guinea Pig Airways

The effect of respiratory tract viral infection on evoked cough in guinea pigs was evaluated. Guinea pigs were inoculated intranasally with either parainfluenza type 3 (PIV3) and cough was quantified in conscious animals. The guinea pigs infected with PIV3 (day 4) coughed nearly three times more than those treated with the viral growth medium in response to capsaicin, citric acid, and bradykinin. Since capsaicin, citric acid, and bradykinin evoked coughing in guinea pigs can be inhibited by drugs that antagonize the transient receptor potential cation channel, subfamily V, member 1 (TRPV1), it was reasoned that the virally-induced hypertussive state may involve alterations in TPRV1 activity. PIV3 infection caused a phenotypic switch in tracheal nodose Aδ “cough receptors” such that nearly 50% of neurons began to express, de novo, TRPV1 mRNA. There was also an increase TRPV1 expression in jugular C-fiber neurons as determined by qPCR. It has previously been reported that tracheal-specific nodose neurons express the BDNF receptor TrkB and jugular neurons express the NGF receptor TrkA. Jugular neurons also express the artemin receptor GFRα3. All these neurotrophic factors have been associated with increases in TRPV1 expression. In an ex vivo perfused guinea pig tracheal preparation, we demonstrated that within 8 h of PIV3 infusion there was no change in NGF mRNA expression, but there was nearly a 10-fold increase in BDNF mRNA in the tissue, and a small but significant elevation in the expression of artemin mRNA. In summary, PIV3 infection leads to elevations in TRPV1 expression in the two key cough evoking nerve subtypes in the guinea pig trachea, and this is associated with a hypertussive state with respect to various TRPV1 activating stimuli.

Inhaled Corticosteroids Use Is Not Associated With an Increased Risk of Pregnancy-Induced Hypertension and Gestational Diabetes Mellitus: Two Nested Case-Control Studies

There have been concerns that systemic corticosteroid use is associated with pregnancy-induced hypertension (PIH) and diabetes mellitus. However, the relationship between inhaled corticosteroids (ICSs) and the risk of PIH has not been fully examined, and there was no study investigating the association between ICS use and the development of gestational diabetes mellitus (GDM). The aims of the study are to determine whether the use of ICSs during pregnancy increases the risk of PIH and GDM in women.We conducted 2 nested case-control studies utilizing the nationwide insurance claims database of the Health Insurance Review and Assessment Service (Seoul, Republic of Korea), in which 1,306,281 pregnant women who delivered between January 1, 2009 and December 31, 2011 were included. Among them, PIH cases and GDM cases were identified and matched controls were included. Conditional logistic regression analyses adjusted by other concomitant drugs use during and before pregnancy and confounding covariates including comorbidities were performed.Total 43,908 PIH cases and 219,534 controls, and 34,190 GDM cases and 170,934 control subjects were identified. When other concomitant drugs use during pregnancy was adjusted, ICS use was associated with an increased rate of PIH (adjusted odds ratio, 1.40 [95% CI, 1.05-1.87]). ICS medication possession ratios and cumulative doses were associated with an increased risk of PIH. However, the statistical significance was not found in other models. In both unadjusted and adjusted multivariable models, ICSs use was not associated with increase in the risk of GDM.ICSs use is not associated with an increased risk of PIH and GDM.

Eosinophilic airway inflammation is common in subacute cough following acute upper respiratory tract infection

BACKGROUND AND OBJECTIVE

Patients presenting with refractory postinfectious cough may respond to glucocorticosteroids but it is unclear whether airway eosinophilic inflammation exists in those patients. We aimed to determine the airway inflammation and causes of subacute cough following acute upper respiratory tract infection (AURTI).

METHODS

One hundred and sixteen patients with persistent cough lasting 3-8 weeks after upper respiratory tract infection were evaluated with differential cell count in induced sputum, spirometry and methacholine bronchial challenge testing.

RESULTS

In patients with subacute cough, sputum eosinophilia (median 8.5%,3.0-73.0%) was identified in 35 (33.6%) patients, 22 (18.5%) without bronchial hyperresponsiveness (BHR) were diagnosed as non-asthmatic eosinophilic bronchitis (NAEB), 13 (14.3%) of whom with BHR were diagnosed as cough variant asthma (CVA). Cough in patients with sputum eosinophilia improved after treatment with corticosteroids. Compared with postinfectious cough (PIC) and NAEB, CVA had significantly higher median eosinophil count in induced sputum (0.5% vs 7.5% vs 20.0%, P < 0.01). MMEF in CVA was significantly lower than PIC and NAEB (P < 0.05). The common causes of subacute cough following acute upper respiratory tract infection (AURTI) were PIC (37.8%), NAEB (18.5%), CVA (14.3%) and upper airway cough syndrome (UACS) (10.1%). Atopic cough (AC) (5.2%) and gastroesophageal reflux-related cough (GERC) (3.4%) were less common in subacute cough following AURTI, while 9 (7.8%) patients had unexplained cough.

CONCLUSION

Subacute cough following AURTI can be attributed to different entities, eosinophilic airway inflammation is common. Induced sputum should be considered when evaluating patients with subacute cough following acute upper respiratory tract infection.

Chronic cough and a normal chest X-ray - a simple systematic approach to exclude common causes before referral to secondary care: a retrospective cohort study

Chronic cough is common in the community and can cause significant morbidity. It is not clear how closely treatment guidelines are used in general practice, or how often specialist referral is indicated. We aimed to assess the management of chronic cough in primary care before referral to a cough clinic, and to assess the outcome of managing chronic cough with an approach of simple investigation and empirical treatment trials. Data were extracted from the records of all patients attending a district general hospital respiratory clinic over a two-year period with isolated chronic cough lasting ⩾8 weeks. The clinic assessed symptoms with a cough-severity visual analogue scale and the Leicester Cough Questionnaire. Among 266 patients, the most frequent diagnoses were asthma (29%), gastro-oesophageal reflux (22%) and angiotensin-converting enzyme inhibitor use (14%). In all, 12% had unexplained chronic cough. Common diagnoses had often not been excluded in primary care: only 21% had undergone spirometry, 86% had undergone chest radiography and attempts to exclude asthma with corticosteroids had been made only in 39%. In the clinic few investigations were conducted that were not available in primary care. Substantial improvements in symptoms occurred with a median (interquartile range) total of 2 (2–3) clinic visits. We estimated that 87% of patients could have been managed solely in primary care; we did not identify distinguishing characteristics among this group. Most cases of chronic cough referred to secondary care could be managed with a simple and systematic approach, which is potentially transferrable to a community setting.

A traditional herbal medication, Maekmoondong-tang, for cough: A systematic review and meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Maekmoondong-tang (MMDT) is a traditional herbal medication widely used to improve cough in Korea, Japan, and China. It is composed of six herbs (Ophiopogonis Tuber, Pinelliae Tuber, Glycyrrhizae Radix, Zizyphi Fructus, Ginseng Radix, and Oryzae Semen).

AIM OF THE STUDY

This study is aimed to systematically review the relevant randomised controlled trials (RCTs) to determine the effectiveness and safety of MMDT for cough.

MATERIALS AND METHODS

Electronic and hand-searching of 7 databases (Cochrane Library, MEDLINE, EMBASE, OASIS, RISS, CNKI and CiNii) was systematically conducted up to February 2015 for RCTs testing MMDT in patients with cough. The primary outcome was cough symptom improvement using cough diary, visual analog scale, or response rate. Risk of bias of the included trials was evaluated with the Cochrane risk of bias assessment tool. The dichotomous data were pooled to obtain a risk ratio (RR) of cough persisting after treatment, with 95% confidence intervals (CI).

RESULTS

Nine RCTs involving 2453 participants were included. The methodological quality was largely poor for a majority of the studies. MMDT reduced the severity of cough by 74% compared with the conventional antitussive medications in various conditions (n=1145; RR of cough persisting after treatment=0.26; 95% CI, 0.19-0.34, I(2)=0%). The addition of MMDT to conventional medication in patients with postinfectious cough significantly alleviated symptoms up to day 5 but the effect was not maintained one week afterwards. For other diseases/conditions including chronic obstructive pulmonary disease, lung cancer surgery, and asthma, the evidence is inconsistent for MMDT/mMMDT for cough. Adverse events appear to be rare but the reporting was poor.

CONCLUSIONS

The current evidence from our systematic review and meta-analysis on MMDT for cough is inconclusive and we propose that rigorously designed, placebo-controlled trials of MMDT should be conducted to establish its place in management of cough.

How does rhinovirus cause the common cold cough?

Cough is a protective reflex to prevent aspiration and can be triggered by a multitude of stimuli. The commonest form of cough is caused by upper respiratory tract infection and has no benefit to the host. The virus hijacks this natural defence mechanism in order to propagate itself through the population. Despite the resolution of the majority of cold symptoms within 2 weeks, cough can persist for some time thereafter. Unfortunately, the mechanism of infectious cough brought on by pathogenic viruses, such as human rhinovirus, during colds, remains elusive despite the extensive work that has been undertaken. For socioeconomic reasons, it is imperative we identify the mechanism of cough. There are several theories which have been proposed as the causative mechanism of cough in rhinovirus infection, encompassing a range of different processes. Those of which hold most promise are physical disruption of the epithelial lining, excess mucus production and an inflammatory response to rhinovirus infection which may be excessive. And finally, neuronal modulation, the most convincing hypothesis, is thought to potentiate cough long after the original stimulus has been cleared. All these hypotheses will be briefly covered in the following sections.

The duration of cough in patients with H1N1 influenza

BACKGROUND

Cough is one of common symptoms of influenza, the cough duration and prevalence of postinfectious cough (PIC) after viral upper respiratory tract infection has not been well described.

OBJECTIVES

We aim to investigate the duration of cough and prevalence of PIC and its relation with acute symptoms, airway inflammation and cough sensitivity in patients with H1N1 influenza.

METHODS

Patients with acute symptoms of H1N1 influenza were enrolled and followed up until cough relived. Spirometry, induced sputum test, capsaicin challenge test were conducted in patients with PIC. Cough sensitivity was presented as logarithm of provocative concentration inducing five or more coughs (logC5).

RESULTS

A total of 141 cases with H1N1 influenza were enrolled. In patients with H1N1 influenza, 97.2% of them complained cough. The duration of cough was as following: <1 week (73.0%); 1-2 weeks (7.8%); 2-3 weeks (7.8%); ≥3 weeks (8.5%). Twelve (8.5%) patients had cough lasting more than 3 weeks (PIC), 4 (2.8%) patients developed chronic cough (>8 weeks). Acute symptoms, spirometry, bronchial responsiveness and sputum differential cell count were similar between patients with PIC and those without PIC, however, there was a higher prevalence of previous PIC (58.3% vs 14.7%, P < 0.05) and elevated cough sensitivity (lgC5: 1.18 ± 0.58 vs 2.73 ± 0.33, P < 0.01) in patients with PIC as compared with the patients without PIC.

CONCLUSIONS

Acute cough is common in patients with H1N1 PIC, only a few of patients develop chronic cough. Acute symptoms cannot predict PIC which is related with previous PIC and increased cough sensitivity.

Efficacy and safety of Qing-Feng-Gan-Ke Granules in patients with postinfectious cough: study protocol of a novel-design phase III placebo-controlled, double-blind randomized trial

BACKGROUND

Postinfectious cough (PIC) is a common condition that affects millions of people worldwide every year. There is Western medicine for this condition but the treatment effect is often incomplete. Traditional Chinese medicine (TCM) has been increasingly prescribed for patients with PIC. Preliminary trials on Qing-Feng-Gan-Ke-Granules (QFGKG) conveyed promising results in treating PIC. This protocol describes an ongoing phase III randomized controlled clinical trial, designed according to a novel methodology of "one study, one primary outcome", with the objective of evaluating the efficacy and safety of QFGKG in patients suffering from PIC.

METHODS/DESIGN

This is a multicenter, phase III, randomized, double-blind, parallel-group, placebo-controlled clinical trial, comprising two simultaneously conducted study parts, part A and part B, intending to investigate two primary outcomes, i.e. time to cough resolution and cough symptom score, respectively. A total of 480 patients, aged 18 to 65 years, who complain of an ongoing persistent cough that has been lasting ≥ 3 weeks, will be recruited from six participating sites and then randomized to receive QFGKG 12.0 g twice daily or placebo 12.0 g twice daily. Each part will enroll 240 patients, with 180 patients being allocated to the QFGKG group and 60 to the placebo group.

DISCUSSION

Although traditional Chinese medicine is a structured intervention that has shown some promise in treating persistent cough, existing unconvincing evidence has noted limitations. This is a rare well-designed and rigorously-controlled, randomized, double-blind trial to evaluate the effects and safety of a Chinese herbal medicine in patients with postinfectious cough, providing tangible benefits for clinical research. Results of this trial are inclined to be conjectured as more truthful by implementing separate study parts that specifically estimate exclusive primary outcome. It will not only provide robust clinical evidence on the efficacy and safety of QFGKG for postinfectious cough, but will also provide a critical piece of information on the availability and superiority of a novel methodology for future clinical trials. The current trial is ongoing with recruitment of the predetermined number of patients being in progress.

TRIAL REGISTRATION

The two parts of this trial were separately registered with the Chinese Clinical Trial Registry: ChiCTR-TRC-13003278 (part A); and ChiCTR-TRC-13003337 (part B).

The efficacy of QingfengGanke granule in treating postinfectious cough in pathogenic wind invading lungs syndrome: a multicenter, randomized, double-blind, placebo-controlled trial

BACKGROUND

Postinfectious cough (PIC) significantly affects cough-related quality of life but still lacks effective treatments. This study aims to investigate the efficacy of QingfengGanke granule (QFGKG) in treating PIC induced by pathogenic wind invading lungs syndrome.

METHODS

A multicenter, randomized, double-blind, placebo-controlled clinical trial was conducted. A total of 180 eligible participants were randomly (1:1:1) assigned to group A (QFGKG 6 g plus QFGKG-matched placebo 6 g), group B (QFGKG 12 g), and group C (QFGKG-matched placebo 12 g). All herbal medications were orally administered twice daily for 10 consecutive days. The primary outcome was time to cough resolution, and secondary outcomes included time to cough alleviation, mean changes in cough symptom score (CSS), visual analogue scale (VAS) score, cough-specific quality of life questionnaire (CQLQ) score, and traditional Chinese medicine (TCM) syndrome score from baseline to Day 10, as well as adverse events.

RESULTS

A total of 173 participants were included in the efficacy and safety analyses (group A, n = 57; group B, n = 57; group C, n = 59). The median time to cough resolution in groups A, B, and C was more than 10 days, 8 days, and more than 10 days, respectively (P < 0.0001), and the median time to cough alleviation was 4, 4, and 6 days, respectively (P < 0.0001). Compared with the placebo condition, groups A and B showed significantly greater improvements in CSS (P = 0.0005, P < 0.0001, respectively), VAS (P = 0.0002, P < 0.0001, respectively), CQLQ (P = 0.0258, P = 0.0003, respectively), and TCM syndrome (P = 0.0031, P < 0.0001, respectively). The time to cough resolution was faster in group B compared with group A (P = 0.0091). The adverse event profiles were comparable among the three groups.

CONCLUSION

QingfengGanke granule is efficacious in the treatment of PIC induced by pathogenic wind invading lungs syndrome.

Honey for acute cough in children

BACKGROUND

Cough causes concern for parents and is a major cause of outpatient visits. It can impact on quality of life, cause anxiety and affect sleep in parents and children. Several remedies, including honey, have been used to alleviate cough symptoms.

OBJECTIVES

To evaluate the effectiveness of honey for acute cough in children in ambulatory settings.

SEARCH METHODS

We searched CENTRAL (2014, Issue 10), MEDLINE (1950 to October week 4, 2014), EMBASE (1990 to November 2014), CINAHL (1981 to November 2014), Web of Science (2000 to November 2014), AMED (1985 to November 2014), LILACS (1982 to November 2014) and CAB abstracts (2009 to January 2014).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing honey given alone, or in combination with antibiotics, versus nothing, placebo or other over-the-counter (OTC) cough medications to participants aged from one to 18 years for acute cough in ambulatory settings.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened search results for eligible studies and extracted data on reported outcomes.

MAIN RESULTS

We included three RCTs, two at high risk of bias and one at low risk of bias, involving 568 children. The studies compared honey with dextromethorphan, diphenhydramine, 'no treatment' and placebo for the effect on symptomatic relief of cough using a seven-point Likert scale. The lower the score, the better the cough symptom being assessed.Moderate quality evidence showed that honey may be better than 'no treatment' in reducing the frequency of cough (mean difference (MD) -1.05; 95% confidence interval (CI) -1.48 to -0.62; I(2) statistic 23%; two studies, 154 participants). High quality evidence also suggests that honey may be better than placebo for reduction of cough frequency (MD -1.85; 95% Cl -3.36 to -0.33; one study, 300 participants). Moderate quality evidence suggests that honey does not differ significantly from dextromethorphan in reducing cough frequency (MD -0.07; 95% CI -1.07 to 0.94; two studies, 149 participants). Low quality evidence suggests that honey may be slightly better than diphenhydramine in reducing cough frequency (MD -0.57; 95% CI -0.90 to -0.24; one study, 80 participants).Adverse events included mild reactions (nervousness, insomnia and hyperactivity) experienced by seven children (9.3%) from the honey group and two (2.7%) from the dextromethorphan group; the difference was not significant (risk ratio (RR) 2.94; 95% Cl 0.74 to 11.71; two studies, 149 participants). Three children (7.5%) in the diphenhydramine group experienced somnolence (RR 0.14; 95% Cl 0.01 to 2.68; one study, 80 participants). When honey was compared with placebo, four children (1.8%) in the honey group and one (1.3%) from the placebo group complained of gastrointestinal symptoms (RR 1.33; 95% Cl 0.15 to 11.74). However, there was no significant difference between honey versus dextromethorphan, honey versus diphenhydramine or honey versus placebo. No adverse event was reported in the 'no treatment' group.

AUTHORS' CONCLUSIONS

Honey may be better than 'no treatment', diphenhydramine and placebo for the symptomatic relief of cough, but it is not better than dextromethorphan. None of the included studies assessed the effect of honey on 'cough duration' because intervention and follow-up were for one night only. There is no strong evidence for or against the use of honey.