Prevalence, aetiologies and prognosis of the symptom cough in primary care: a systematic review and meta-analysis

A systematic review of the psychometric properties of the Leicester Cough Questionnaires based on the COSMIN Guidelines

BACKGROUND

Chronic cough affects around 10% of the general adult population, impairing all aspects of quality of life.

RESEARCH QUESTION

What are the Leicester Cough Questionnaire's psychometric properties?

STUDY DESIGN AND METHODS

Electronic searches of PubMed, CINAHL, and ScienceDirect databases were conducted from inception until October 1rst 2022. All full-text articles, published in French or English, aimed at evaluating the LCQ's content validity or psychometric properties were included. The COSMIN Risk of Bias checklist was applied to assess their methodological quality and results. Results were qualitatively summarised and rated by a modified GRADE approach.

RESULTS

40 studies were included accounting for 8,731 adults, subject to cough or a respiratory condition. Chronic cough (> 8 weeks) was the most represented. The LCQ's total score is relevant and comprehensible for the assessment of the impact of cough on QoL. The original 3-factor model showed a satisfactory model fit. Good convergent validity was found for the total and physical domain scores. These scores demonstrate good internal consistency and test retest reliability, with some variability noted and they are responsive to change. Recent estimates of MID thresholds were 1.7 and 0.4 for total and domain scores respectively. The quality of the studies is globally poor.

INTERPRETATION

The LCQ is a valid outcome to assess the intra-individual impact of cough on QoL and to detect large changes in quality of life mainly in a short-term clinical trial setting.

CLINICAL TRIAL REGISTRATION

The protocol was registered with PROSPERO (CRD42XXXXX).

The Effect of Long-Term Azithromycin on Objective and Subjective Cough in Chronic Respiratory Disease: A Systematic Review and Meta-analysis of Randomised Controlled Trials and Noncomparative Studies

INTRODUCTION

Azithromycin is an effective treatment for various respiratory conditions but its effect on cough is poorly understood. We synthesised data from randomised controlled trials (RCTs) and noncomparative studies (NCT) examining its effect on objective and subjective cough.

METHODS

After prospective registration on PROSPERO, we searched MEDLINE, EMBASE, and CENTRAL for both RCTs and NCT trials examining the effect azithromycin on cough in respiratory disease.

RESULTS

We identified 1240 studies of which 6 (4 RCTs and 2 NCT studies) were included in the meta-analysis, with a total of 275 patients. Azithromycin was associated with significant improvement in Leicester Cough Questionnaire scores at follow-up when compared to baseline scores (SMD = 0.62 [95% CI 0.12 to 1.12], p = 0.01). However, when only RCTs were synthesised, no significant effect was observed (SMD = 0.12 [95% CI - 0.36 to 0.60], p = 0.62). There was no significant reduction in cough severity VAS score (SMD = - 0.39 [95% CI - 0.92 to 0.14], p = 0.15). There was no significant reduction in objective cough count (SMD = - 0.41 [95% CI - 1.04 to 0.32], p = 0.09).

CONCLUSION

Azithromycin therapy improves cough-related quality of life in various chronic respiratory diseases; however, there was no significant effect on cough outcomes when only data from RCTs were synthesised. We believe that to accurately identify which patients whose cough would benefit from azithromycin a large-scale clinical trial of patients with a broad spectrum of respiratory diseases, with sufficiently severe cough, should be undertaken with subgroup analysis of individual disease areas.

Pharmacists' clinical decision making when responding to a self-medication request for a cough in a developing country

BACKGROUND

Some studies have reported that community pharmacies in developing countries, including Indonesia, provided sub-optimal advice when handling patient's self-medication request for cough. The reasons behind such advice, therefore, need to be investigated.

OBJECTIVES

To describe Indonesian pharmacists' clinical decision making when handling self-medication cases for a cough.

METHODS

An open-ended questionnaire consisting of two cough clinical vignettes (case 1: cough due to asthma worsening and case 2: cough as a symptom of common cold) were developed. Pharmacists were interviewed to provide recommendations and reasons for their recommendations for these scenarios. Content analysis was used to analyse participants' statements for the two scenarios. The number of participants who provided appropriate recommendations and reasons were then counted.

RESULTS

A total of 245 community pharmacists participated in the study. In the case of cough due to asthma worsening, recommending a product because the product was indicated to help with the symptoms was the most common recommendation and stated reason (40%). Appropriate recommendation (direct medical referral) with appropriate reasoning (indicating warning symptoms and/or making a symptom diagnosis) was provided by 25% participants. In the case of cough as a symptom of common cold, recommending products to help with the symptoms was also the most common recommendation and stated reason (53%). Appropriate recommendations (recommending product) with appropriate reasoning (providing product to treat the symptoms and/or indicating no warning symptoms and/or making a symptom diagnosis) was provided by 81% participants.

CONCLUSION

The ability of Indonesian community pharmacists to provide appropriate recommendations for cough self-medication requests is dependent on whether triage is required. The inability of most community pharmacists to differentiate between major and minor conditions may lead to serious health implications for patients and therefore educational interventions should be undertaken to improve community pharmacists' differential diagnostic skills for triage.

Effects of C-reactive protein rapid testing and communication skills training on antibiotic prescribing for acute cough. A cluster factorial randomised controlled trial

This cluster randomised clinical trial carried out in 20 primary care centres in Barcelona was aimed at assessing the effect of a continuous intervention focused on C-reactive protein (CRP) rapid testing and training in enhanced communication skills (ECS) on antibiotic consumption for adults with acute cough due to lower respiratory tract infection (LRTI). The interventions consisted of general practitioners and nurses' use of CRP point-of-care and training in ECS separately and combined, and usual care. The primary outcomes were antibiotic consumption and variation of the quality-adjusted life years during a 6-week follow-up. The difference in the overall antibiotic prescribing between the winter seasons before and after the intervention was calculated. The sample size calculated could not be reached due to the COVID-19 outbreak. A total of 233 patients were recruited. Compared to the usual care group (56.7%) antibiotic consumption among patients assigned to professionals in the ECS group was significantly lower (33.9%, adjusted odds ratio [aOR] 0.38, 95% CI 0.15-0.94, p = 0.037), whereas patients assigned to CRP consumed 43.8% of antibiotics (aOR 0.70, 95% CI 0.29-1.68, p = 0.429) and 38.4% in the combined intervention group (aOR 0.45, 95% CI, 0.17-1.21; p = 0.112). The overall antibiotic prescribing rates in the centres receiving training were lower after the intervention compared to those assigned to usual care, with significant reductions in β-lactam rates. Patient recovery was similar in all groups. Despite the limited power due to the low number of patients included, we observed that continuous training achieved reductions in antibiotic consumption.

Prevalence and causes of chronic cough in Japan

BACKGROUND

Chronic cough is one of the most common symptoms of respiratory diseases and can adversely affect patients' quality of life and interfere with social activities, resulting in a significant social burden. A survey is required to elucidate the frequency and treatment effect of chronic cough. However, clinical studies that cover all of Japan have not yet been conducted.

METHODS

Patients who presented with a cough that lasted longer than 8 weeks and visited the respiratory clinics or hospitals affiliated with the Japan Cough Society during the 2-year study period were registered.

RESULTS

A total of 379 patients were enrolled, and those who did not meet the definition of chronic cough were excluded. A total of 334 patients were analyzed: 201 patients had a single cause, and 113 patients had two or more causes. The main causative diseases were cough variant asthma in 92 patients, sinobronchial syndrome (SBS) in 36 patients, atopic cough in 31 patients, and gastroesophageal reflux (GER)-associated cough in 10 patients. The time required to treat undiagnosed patients and those with SBS was significantly longer and the treatment success rate for GER-associated cough was considerably poor.

CONCLUSIONS

We confirmed that the main causes of chronic cough were cough variant asthma, SBS, atopic cough, and their complications. We also showed that complicated GER-associated cough was more likely to become refractory. This is the first nationwide study in Japan of the causes and treatment effects of chronic cough.

Prognostic factors and prediction models for hospitalisation and all-cause mortality in adults presenting to primary care with a lower respiratory tract infection: a systematic review

OBJECTIVE

To identify and synthesise relevant existing prognostic factors (PF) and prediction models (PM) for hospitalisation and all-cause mortality within 90 days in primary care patients with acute lower respiratory tract infections (LRTI).

DESIGN

Systematic review.

METHODS

Systematic searches of MEDLINE, Embase and the Cochrane Library were performed. All PF and PM studies on the risk of hospitalisation or all-cause mortality within 90 days in adult primary care LRTI patients were included. The risk of bias was assessed using the Quality in Prognostic Studies tool and Prediction Model Risk Of Bias Assessment Tool tools for PF and PM studies, respectively. The results of included PF and PM studies were descriptively summarised.

RESULTS

Of 2799 unique records identified, 16 were included: 9 PF studies, 6 PM studies and 1 combination of both. The risk of bias was judged high for all studies, mainly due to limitations in the analysis domain. Based on reported multivariable associations in PF studies, increasing age, sex, current smoking, diabetes, a history of stroke, cancer or heart failure, previous hospitalisation, influenza vaccination (negative association), current use of systemic corticosteroids, recent antibiotic use, respiratory rate ≥25/min and diagnosis of pneumonia were identified as most promising candidate predictors. One newly developed PM was externally validated (c statistic 0.74, 95% CI 0.71 to 0.78) whereas the previously hospital-derived CRB-65 was externally validated in primary care in five studies (c statistic ranging from 0.72 (95% CI 0.63 to 0.81) to 0.79 (95% CI 0.65 to 0.92)). None of the PM studies reported measures of model calibration.

CONCLUSIONS

Implementation of existing models for individualised risk prediction of 90-day hospitalisation or mortality in primary care LRTI patients in everyday practice is hampered by incomplete assessment of model performance. The identified candidate predictors provide useful information for clinicians and warrant consideration when developing or updating PMs using state-of-the-art development and validation techniques.

PROSPERO REGISTRATION NUMBER

CRD42022341233.

Honey for acute cough in children - a systematic review

To analyze the efficacy of using honey to treat acute cough in children. Systematic review, synthesis without meta-analysis. We searched PubMed, Scopus, CENTRAL, CINAHL, and Web of Science databases on August 15, 2022, for words honey and cough. Randomized controlled trials conducted in children were included. Risk-of-bias and evidence quality were assessed. Studies were not pooled due to lack of key information. Instead, we provided the range of observed effects for the main outcomes. Three hundred ninety-six papers were screened, and 10 studies were included. Two studies had high risk-of-bias and six had some concerns. Honey seemed to decrease cough frequency more than placebo/no treatment (range of observed effect 0.0-1.1 points) and cough medication (0.2-0.9 points). Sleep improved more often in the honey group (range of effect was 0.0-1.1) compared to placebo/no treatment and (- 0.2-1.1 points) compared to cough medication. Quality of the evidence was low to very low.

CONCLUSION

We found low quality evidence that honey may be more effective than cough medication or placebo/no treatment in relieving symptoms and improving sleep in children with acute cough. Better quality randomized, placebo-controlled blinded trials are needed to confirm the effectiveness of honey in treating acute cough in children.

TRIAL REGISTRATION

CRD42022369577.

WHAT IS KNOWN

• Honey has been suggested to be effective as a symptomatic treatment in acute cough. • Prior randomized trials have had conflicting results and thus an overview of the literature was warranted.

WHAT IS NEW

• Based on low quality evidence honey may be more effective than placebo or over-the-counter medications for acute symptom reliwef in cough. • Future studies with better reporting are needed to confirm the results.

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.