The use of a direct bronchial challenge test in primary care to diagnose asthma

Neutrophil-to-lymphocyte ratio, platelets-to-lymphocyte ratio, and red cell distribution width as prognostic indicators for length of hospital stay in pediatric asthma

OBJECTIVES

To examine the relationship between neutrophil-to-lymphocyte ratio (NLR), platelets-to-lymphocyte ratio (PLR), and red cell distribution width (RDW) and the length of hospital stay (LOS) in children with bronchial asthma METHODS: This hospital-based study examined the records of children with asthma admitted to Jazan Hospitals, Jazan, Kingdom of Saudi Arabia. Data were extracted at the time of admission. Length of hospital stay and laboratory parameters were acquired from blood.

RESULTS

This study involved 489 children, with a mean age of 5.8±3.5 years, of which 59.7% were male. Notably, 77.7% of the patients resided in rural areas of Jazan. The mean LOS was 3.38±0.35 days, with 2.9% having a short stay (<24 hours) and 64.2% categorized as having a medium stay (1-3 days). The mean NLR was 5.33±1.20, with 46.8% falling within the normal range. Similarly, the mean PLR was 184.84±16.55, with 42.7% classified as normal. The PLR and LOS were shown to be significantly correlated (p=0.021), while no such association existed for NLR or RDW with LOS. Among the blood biomarkers assessed, PLR demonstrated the highest predictive value for LOS in children with asthma, yielding an area under the curve of 0.664 (confidence interval: 0.606-0.723; p=0.000).

CONCLUSION

The findings showed no significant association between NLR and RDW with LOS. Conversely, a notable correlation was observed between PLR and LOS, suggesting that PLR may serve as a valuable predictive marker for LOS in pediatric patients with asthma.

Measuring burden of disease in both asthma and COPD by merging the ACQ and CCQ: less is more?

Symptoms of asthma and COPD often overlap, and both diseases can co-exist in one patient. The asthma control questionnaire (ACQ) and clinical COPD questionnaire (CCQ) were developed to assess disease burden in respectively asthma or COPD. This study explores the possibility of creating a new questionnaire to assess disease burden in all obstructive lung diseases by integrating and reducing questions of the ACQ and CCQ. Data of patients with asthma, COPD and asthma-COPD overlap (ACO) were collected from a primary and secondary care center. Patients completed ACQ and CCQ on the same day. Linear regression tested correlations. Principal Component Analysis (PCA) was used for item reduction. The secondary cohort with asthma and COPD patients was used for initial question selection (development cohort). These results were reproduced in the primary care cohort and secondary cohort of patients with ACO. The development cohort comprised 252 patients with asthma and 96 with COPD. Correlation between ACQ and CCQ in asthma was R = 0.82, and in COPD R = 0.83. PCA determined a selection of 9 questions. Reproduction in primary care data (asthma n = 1110, COPD n = 1041, ACO = 355) and secondary care data of ACO patients (n = 53) resulted in similar correlations and PCA-derived selection of questions. In conclusion, PCA determined a selection of nine questions of the ACQ and CCQ: working title 'the Obstructive Lung Disease Questionnaire'. These results suggest that this pragmatic set of questions might be sufficient to assess disease burden in obstructive lung disease in both primary as secondary care.

Airway hyperresponsiveness in asthma: The role of the epithelium

Airway hyperresponsiveness (AHR) is a key clinical feature of asthma. The presence of AHR in people with asthma provides the substrate for bronchoconstriction in response to numerous diverse stimuli, contributing to airflow limitation and symptoms including breathlessness, wheeze, and chest tightness. Dysfunctional airway smooth muscle significantly contributes to AHR and is displayed as increased sensitivity to direct pharmacologic bronchoconstrictor stimuli, such as inhaled histamine and methacholine (direct AHR), or to endogenous mediators released by activated airway cells such as mast cells (indirect AHR). Research in in vivo human models has shown that the disrupted airway epithelium plays an important role in driving inflammation that mediates indirect AHR in asthma through the release of cytokines such as thymic stromal lymphopoietin and IL-33. These cytokines upregulate type 2 cytokines promoting airway eosinophilia and induce the release of bronchoconstrictor mediators from mast cells such as histamine, prostaglandin D2, and cysteinyl leukotrienes. While bronchoconstriction is largely due to airway smooth muscle contraction, airway structural changes known as remodeling, likely mediated in part by epithelial-derived mediators, also lead to airflow obstruction and may enhance AHR. In this review, we outline the current knowledge of the role of the airway epithelium in AHR in asthma and its implications on the wider disease. Increased understanding of airway epithelial biology may contribute to better treatment options, particularly in precision medicine.

The Fractional exhaled Nitric Oxide (FeNO)- test as add-on test in the diagnostic work-up of asthma: a study protocol

BACKGROUND

Asthma is a common disease characterized by chronic inflammation of the lower airways, bronchial hyperactivity, and (reversible) airway obstruction. The Global Initiative of Asthma Guideline recommends a flowchart to diagnose asthma with first-step spirometry with reversibility and a bronchial challenge test (BPT) with histamine or methacholine as a second step [1]. The BPT is considered burdensome, time-consuming for patients and staff, can cause side effects, and is expensive. In addition, this test strongly encumbers lung function capacity. Elevated Nitric Oxide (NO) is associated with airway eosinophilic inflammation in asthma patients and can be measured in exhaled air with the Fractional exhaled (Fe) NO-test. This low-burden FeNO-test could be used as an 'add-on' test in asthma diagnostics [2, 3].

METHODS AND ANALYSIS

This multi-center prospective study (Trial number: NCT06230458) compares the 'standard asthma diagnostic work-up' (spirometry with reversibility and BPT) to the 'new asthma diagnostics work-up' (FeNO-test as an intermediate step between the spirometry with reversibility and the BPT), intending to determine the impact of the FeNO-based strategy, in terms of the number of avoided BPTs, cost-effectiveness and reduced burden to the patient and health care. The cost reduction of incorporating the FeNO-test in the new diagnostic algorithm will be established by the number of theoretically avoided BPT. The decrease in burden will be studied by calculating differences in the Visual Analogue Scale (VAS) -score and Asthma Quality of Life Questionnaire (AQLQ) -score after the BPT and FeNO-test with an independent T-test. The accuracy of the FeNO-test will be calculated by comparing the FeNO-test outcomes to the (gold standard) BPTs outcomes in terms of sensitivity and specificity. The intention is to include 171 patients.

ETHICS AND DISSEMINATION

The local medical ethics committee approved the proposed study and is considered a low-burden and risk-low study. The local medical ethics committee registration number: R23.005.

STRENGTHS AND LIMITATIONS OF THIS STUDY

Strengths: This is the first study that investigates the value of the FeNO-test (cut off ≥ 50 ppb) as an add-on test, to determine the impact of the FeNO-based strategy, in terms of the number of avoided BPTs, cost-effectiveness, and reduced burden on the patient and health care.

LIMITATIONS

High FeNO levels may also be observed in other diseases such as eosinophilic chronic bronchitis and allergic rhinitis. The FeNO-test can be used to rule in a diagnosis of asthma with confidence, however, due to the poor sensitivity it is not suitable to rule out asthma.

Implementing integrated care guidelines in asthma and COPD: It ain't easy!

Objective

To evaluate the implementation of a guideline-based, integrated, standardised, personal approach in patients with Chronic Obstructive Pulmonary Disease (COPD) or Asthma in a real-life situation.

Methods

Patients at the outpatient clinic of the department of pulmonary disease were included in a controlled cohort study, comparing the use of diagnostic items and 'Personalised care plans' (PCPs) in patients with obstructive lung disease before (2013) and after (2015) implementation of a personalised diagnostic pathway. Results were compared with reference data (2016) from two control hospitals that used the same guidelines but did not implement this pathway.

Results

100 patients were selected for all three cohorts. After implementing the diagnostic pathway in 2015, 35 % of patients visited attended all pre-planned appointments, whereas 65 % of patients did not: they were diagnosed using usual care. Factors contributing to patients not attending the diagnostic care pathway were: the logistical complexity and intensity of the 2-day pathway, patients willingness to participate in a personalised pathway, and low social economic status or low literacy. After the implementation of the pathway, a significant improvement was seen in the number of PCPs (P < 0.001) and the number of diagnostic items registered recorded in the patients' electronic medical records (P < 0.001).

Conclusion

Implementing a standardised diagnostic pathway in a real-life population significantly improved the number of personalised care plans, demonstrating that the implementation of holistic care planning is feasible in this population. Nevertheless, the pathway needs further improvements to maximize the number of patients benefitting from it, including logistical streamlining, removing unnecessary diagnostic tools, and increasing the focus on low literacy. Additionally, we found that implementing existing guidelines in a real life context is complex. Therefore, it is required to prioritize the translation of current guidelines into every-day practice, before expanding existing guidelines and protocols.

Prediction of bronchodilation test in adults with chronic cough suspected of cough variant asthma

Background

Many patients with cough variant asthma (CVA) are underdiagnosed and undertreated due to the atypical symptoms, low diagnostic sensitivity of bronchodilator response (BDR), and limited application of bronchial challenge test.

Objective

To investigate whether airway reversibility in BDR can predict CVA diagnosis in patients with chronic cough and negative BDR.

Methods

This open-label, prospective cohort study included patients with chronic cough, nearly normal chest CT scan, and negative BDR results. Inhaled corticosteroids and long-acting β₂ agonists were given for 4 weeks. The confirmed diagnosis of CVA was defined as improved symptoms and an increase of forced expiratory volume in 1 s (FEV₁) by >12% and >200 mL after 4 weeks of treatment.

Results

Of 155 patients recruited, 140 completed the study. Patients in the CVA positive diagnosis group had greater absolute (Δ) and percent (Δ%) improvements in FEV₁ and forced expiratory flows (FEFs), and higher fractional exhaled nitric oxide (FENO) than in the CVA negative diagnosis group. The area under the receiver operating characteristic curves (AUCs) of ΔFEV₁%, FEF_25-75%pred (percentage of predicted forced expiratory flow at 25% to 75%) and FENO for CVA positive diagnosis was 0.825, 0.714, and 0.637, with cutoff values of 5.90%, 61.99% and 41.50 ppb, respectively. A joint model of ΔFEV₁% combined with FEF_25-75%pred or FENO increased the AUC to 0.848 and 0.847, respectively.

Conclusion

ΔFEV₁% in BDR can predict a CVA diagnosis and response to anti-asthma treatment in patients with chronic cough and negative BDR.

Clinical trial registration

[http://www.chictr.org.cn/index.aspx], identifier [ChiCTR2000029065].

Diagnostic differentiation between asthma and COPD in primary care using lung function testing

Asthma and COPD are defined as different disease entities, but in practice patients often show features of both diseases making it challenging for primary care clinicians to establish a correct diagnosis. We aimed to establish the added value of spirometry and more advanced lung function measurements to differentiate between asthma and COPD. A cross-sectional study in 10 Dutch general practices was performed. 532 subjects were extensively screened on respiratory symptoms and lung function. Two chest physicians assessed if asthma or COPD was present. Using multivariable logistic regression analysis we assessed the ability of three scenarios (i.e. only patient history; diagnostics available to primary care; diagnostics available only to secondary care) to differentiate between the two conditions. Receiver operator characteristics (ROC) curves and area under the curve (AUC) were calculated for each scenario, with the chest physicians’ assessment as golden standard. Results showed that 84 subjects were diagnosed with asthma, 138 with COPD, and 310 with no chronic respiratory disease. In the scenario including only patient history items, ROC characteristics of the model showed an AUC of 0.84 (95% CI 0.78–0.89) for differentiation between asthma and COPD. When adding diagnostics available to primary care (i.e., pre- and postbronchodilator spirometry) AUC increased to 0.89 (95% CI 0.84–0.93; p = 0.020). When adding more advanced secondary care diagnostic tests AUC remained 0.89 (95% CI 0.85–0.94; p = 0.967). We conclude that primary care clinicians’ ability to differentiate between asthma and COPD is enhanced by spirometry testing. More advanced diagnostic tests used in hospital care settings do not seem to provide a better overall diagnostic differentiation between asthma and COPD in primary care patients.

Addressing unmet needs for diagnosis and management of chronic cough in the primary care setting

Chronic cough (i.e. cough lasting >8 weeks) has a global prevalence of approximately 10% and is associated with substantial patient burden, including social, psychological, and physical impairments. This burden can be long-lasting, with some patients experiencing cough for many years. Although chronic cough is often a symptom of respiratory diseases (e.g. interstitial lung disease, chronic obstructive pulmonary disease) or is associated with comorbid conditions (e.g. asthma, gastroesophageal reflux disease) and may resolve after targeted treatment of these conditions, some patients continue to cough despite optimal treatment of associated conditions (refractory chronic cough (RCC)) or have no identifiable conditions presumed to be contributing to the cough (unexplained chronic cough (UCC)). As both RCC and UCC are diagnoses of exclusion, it is critical to perform a thorough initial patient assessment with adherence to diagnostic guidelines to accurately identify RCC and UCC and provide appropriate treatment. Primary care physicians may be in an important position to provide the initial diagnostic workup of patients with chronic cough as well as identify when referral to specialists (e.g. pulmonologists, allergists, otolaryngologists) is appropriate. In this narrative review, current diagnosis and management guidelines for chronic cough are summarized and recommendations for diagnostic workup in a primary care setting are provided. Increased appreciation of chronic cough as a distinct condition, rather than as only a symptom of other diseases, may help overcome current challenges in diagnosing and managing chronic cough and reduce patient burden.

Spirometric Changes in Bronchodilation Tests as Predictors of Asthma Diagnosis and Treatment Response in Patients with FEV1 ≥ 80% Predicted

BACKGROUND

Many patients with mild asthma are undiagnosed and untreated due to the low diagnostic sensitivity of bronchodilation test (BDT).

OBJECTIVE

To investigate whether airway reversibility in BDT and fractional exhaled nitric oxide (Feno) can predict the response to antiasthma therapy (RAT) in patients with suspected asthma.

METHODS

This open-label, prospective cohort study included patients with chronic recurrent asthma symptoms, normal FEV₁, and negative BDT results. Inhaled corticosteroids and long-acting β agonists were given for 4 weeks. A positive RAT was defined as improved symptoms and an increase of more than 200 mL in FEV₁ after inhaled corticosteroid/long-acting β agonist treatment. Lung tissues from another 19 patients who underwent pneumectomy for lung nodules were also analyzed.

RESULTS

Of 110 patients recruited, 102 completed the study. Patients in the positive RAT group had a higher Feno and greater absolute (Δ) and percent (Δ%) improvements in forced vital capacity, FEV₁, and forced expiratory flows (FEFs) in BDT than in the negative RAT group. The area under the curves of Feno, ΔFEV₁%, ΔFEF_25-75% (percent improvement in FEF at 25%-75% of forced vital capacity), and ΔFEF₇₅% (percent improvement in FEF at 75% of forced vital capacity) for positive RAT were 0.703, 0.824, 0.736, and 0.710, with cutoff values of 33 parts per billion and 3.50%, 15.26%, and 26.04%, respectively. A joint model of Feno and ΔFEV₁% increased the area under the curve to 0.880. Inflammatory cytokines were higher in the lung tissues of patients with predicted positive RAT than in those with predicted negative RAT.

CONCLUSIONS

ΔFEV₁% in BDT together with Feno predicted a positive RAT and an asthma diagnosis in patients with a normal FEV₁ and negative BDT. Evidence of pathological changes increases the credibility of the predictive model.