The impact of normalization of esophageal acid profile by incremental protein pump inhibitors dosing in difficult asthma patients with proven gastro-esophageal acid reflux

Pharmacological and surgical interventions for the treatment of gastro-oesophageal reflux in adults and children with asthma

BACKGROUND

Asthma and gastro-oesophageal reflux disease (GORD) are common medical conditions that frequently co-exist. GORD has been postulated as a trigger for asthma; however, evidence remains conflicting. Proposed mechanisms by which GORD causes asthma include direct airway irritation from micro-aspiration and vagally mediated oesophagobronchial reflux. Furthermore, asthma might precipitate GORD. Thus a temporal association between the two does not establish that GORD triggers asthma.

OBJECTIVES

To evaluate the effectiveness of GORD treatment in adults and children with asthma, in terms of its benefits for asthma.

SEARCH METHODS

The Cochrane Airways Group Specialised Register, CENTRAL, MEDLINE, Embase, reference lists of articles, and online clinical trial databases were searched. The most recent search was conducted on 23 June 2020.

SELECTION CRITERIA

We included randomised controlled trials comparing treatment of GORD in adults and children with a diagnosis of both asthma and GORD versus no treatment or placebo.

DATA COLLECTION AND ANALYSIS

A combination of two independent review authors extracted study data and assessed trial quality. The primary outcome of interest for this review was acute asthma exacerbation as reported by trialists.

MAIN RESULTS

The systematic search yielded a total of 3354 citations; 23 studies (n = 2872 participants) were suitable for inclusion. Included studies reported data from participants in 25 different countries across Europe, North and South America, Asia, Australia, and the Middle East. Participants included in this review had moderate to severe asthma and a diagnosis of GORD and were predominantly adults presenting to a clinic for treatment. Only two studies assessed effects of intervention on children, and two assessed the impact of surgical intervention. The remainder were concerned with medical intervention using a variety of dosing protocols. There was an uncertain reduction in the number of participants experiencing one or more moderate/severe asthma exacerbations with medical treatment for GORD (odds ratio 0.53, 95% confidence interval (CI) 0.17 to 1.63; 1168 participants, 2 studies; low-certainty evidence). None of the included studies reported data related to the other primary outcomes for this review: hospital admissions, emergency department visits, and unscheduled doctor visits. Medical treatment for GORD probably improved forced expiratory volume in one second (FEV₁) by a small amount (mean difference (MD) 0.10 L, 95% CI 0.05 to 0.15; 1333 participants, 7 studies; moderate-certainty evidence) as well as use of rescue medications (MD -0.71 puffs per day, 95% CI -1.20 to -0.22; 239 participants, 2 studies; moderate-certainty evidence). However, the benefit of GORD treatment for morning peak expiratory flow rate was uncertain (MD 6.02 L/min, 95% CI 0.56 to 11.47; 1262 participants, 5 studies). It is important to note that these mean improvements did not reach clinical importance. The benefit of GORD treatment for outcomes synthesised narratively including benefits of treatment for asthma symptoms, quality of life, and treatment preference was likewise uncertain. Data related to adverse events with intervention were generally underreported by the included studies, and those that were available indicated similar rates regardless of allocation to treatment or placebo.

AUTHORS' CONCLUSIONS

Effects of GORD treatment on the primary outcomes of number of people experiencing one or more exacerbations and hospital utilisation remain uncertain. Medical treatment for GORD in people with asthma may provide small benefit for a number of secondary outcomes related to asthma management. This review determined with moderate certainty that with treatment, lung function measures improved slightly, and use of rescue medications for asthma control was reduced. Further, evidence is insufficient to assess results in children, or to compare surgery versus medical therapy.

Does omeprazole improve asthma-control in poorly-controlled asthmatic children with gastro-esophageal reflux

OBJECTIVES

The role of gastro-esophageal reflux disease (GERD) in poorly controlled asthma is often mentioned, but published studies have presented discordant results. Our main objective was to assess the effectiveness of GERD treatment in controlling asthma in children.

METHODS

We conducted a prospective study including poorly controlled asthmatic children aged 4 to 16 years. We checked the presence of acid reflux using pH monitoring. Patients with GERD were randomized into two groups; one received omeprazole for 6 months and the control group was not treated. The outcome was the score of the children asthma control test at the end of 6 months. The acid suppression was checked at the end of treatment with pH monitoring. After treatment, children with persistent acid reflux received high PPI doses and therefore were reevaluated 6 months later.

RESULTS

We included 102 children with poorly controlled asthma among which 59 (57.8%) had acid reflux. Gastroesophageal reflux (GER) was significantly more common in boys (p = 0.04). Treatment with omeprazole in sufficient doses improved the control of asthma in 5 children out of 6 (84.8 vs 11.5; p<.0001). Three factors appeared to be statistically associated with asthma control improvement after PPI therapy: male sex (p=.04), normal birth weight (p=.05) and a positive Prick-test (p=.05). These factors were not confirmed or were not sufficiently precise in multivariate analysis. The likelihood of a causal relationship between acid reflux and asthma, difficult to highlight with pH monitoring, was poor.

CONCLUSIONS

This study confirmed the high prevalence of GER in poorly controlled asthmatic children and showed the possible benefit of an efficient GER treatment in improving asthma control.

Current therapies for gastro-oesophageal reflux in the setting of chronic lung disease: state of the art review

The inter-relationship between chronic respiratory disease and reflux disease in the airway reflux paradigm is extremely complex and remains poorly characterised. Reflux disease is reported to cause or contribute to the severity of a number of respiratory tract diseases including laryngeal disorders, sinusitis, chronic cough, asthma, COPD, idiopathic pulmonary fibrosis, cystic fibrosis, bronchiectasis and bronchiolitis obliterans post lung transplant. It is now appreciated that reflux disease is not simply caused by liquid acid reflux but rather by a variety of chemical refluxates originating from the stomach and duodenum due to a number of different mechanisms. Reflux disease can be challenging to diagnose, particularly proving its role in the causation of direct respiratory epithelial damage. Significant advances in oesophageal assessment and gastric biomarkers have emerged in recent years as our understanding increases. There are a number of treatments available for reflux disease, both medical and surgical, but there is a paucity of large randomised trials to evaluate their efficacy in the setting of chronic respiratory disease. Everyday clinical practice, however, informs us that treatment failure in reflux disease is common. This clinical review summarises associations between reflux disease in the setting of chronic respiratory diseases and examines available evidence regarding potential therapeutic strategies.

Gastro-oesophageal reflux disease is prevalent among patients with chronic respiratory disease. A number of medical and surgical treatment options are available for GORD. This review examines available evidence in the setting of chronic lung disease.https://bit.ly/34TcMJS

Model to Select On-Therapy vs Off-Therapy Tests for Patients With Refractory Esophageal or Extraesophageal Symptoms

BACKGROUND & AIMS

It is not clear whether we should test for reflux in patients with refractory heartburn or extraesophageal reflux (EER) symptoms, such as cough, hoarseness, or asthma. Guidelines recommend testing patients by pH monitoring when they are on or off acid-suppressive therapies based on pretest probability of reflux, determined by expert consensus. However, it is not clear what constitutes a low or high pretest probability of reflux in these patients. We aimed to develop a model that clinicians can use at bedside to estimate pretest probability of abnormal reflux.

METHODS

We performed a prospective study of 471 adult patients with refractory heartburn (n = 214) or suspected EER symptoms (n = 257) who underwent endoscopy with wireless pH monitoring while they were off acid-suppressive treatment and assigned them to groups based on symptoms at presentation (discovery cohort). Using data from the discovery cohort, we performed proportional odds ordinal logistic regression to select factors (easy to obtain demographic criteria and clinical symptoms such as heartburn, regurgitation, asthma, cough, and hoarseness) associated with esophageal exposure to acid. We validated our findings in a cohort of 118 patients with the same features from 2 separate tertiary care centers (62% women; median age 59 years; 62% with cough as presenting symptom).

RESULTS

Abnormal pH (>5.5% of time spent at pH <4) was found in 56% of patients with heartburn and 63% of patients with EER (P = .15). Within EER groups, abnormal pH was detected in a significantly larger proportion (80%) of patients with asthma compared with patients with cough (60%) or hoarseness (51%; P < .01). Factors significantly associated with abnormal pH in patients with heartburn were presence of hiatal hernia and body mass index >25 kg/m². In patients with EER, the risk of reflux was independently associated with the presence of concomitant heartburn (odds ratio [OR] 2.0; 95% confidence interval [CI] 1.3-3.1), body mass index >25 kg/m² (OR 2.1; 95% CI 1.5-3.1), asthma (OR 2.0; 95% CI 1.2-3.5), and presence of hiatal hernia (OR 1.9; 95% CI 1.2-3.1). When we used these factors to create a scoring system, we found that a score of ≤2 excluded patients with moderate to severe reflux, with a negative predictive value of 80% in the discovery cohort and a negative predictive value of 85% in the validation cohort.

CONCLUSION

We developed a clinical model to estimate pretest probability of abnormal pH in patients who were failed by proton pump inhibitor therapy. This system can help guide clinicians at bedside in determining the most appropriate diagnostic test in this challenging group of patients.

Clinical features of asthma in children differ with regard to the intensity of distal gastroesophageal acid reflux

BACKGROUND

The prevalence of gastroesophageal reflux (GER) in children with asthma is higher than in healthy controls, but the nature and direction of this association is unclear.

OBJECTIVE

The aim of our study was to assess the relationship between esophageal acid exposure and the clinical features of asthma in children.

METHODS

In total, 66 children (mean age 122.8 months [SD 44.89 months]) with chronic pulmonary symptoms, fulfilling diagnostic criteria of persistent asthma, underwent 24-hour esophageal pH monitoring and answered a detailed questionnaire-based survey. The questionnaire topics included environmental factors, familial history, current and previous clinical symptoms, atopy, asthma severity, and medication.

RESULTS

Abnormal results of 24-hour esophageal pH monitoring were found in 28 out of 66 children (42.4%). Age, sex, severity of asthma, environmental factors, spirometry results, and the type of medication did not correlate with esophageal acid exposure. However, children with abnormal pH results developed asthma significantly earlier (asthma onset 3.63 years [SD 2.52 years] vs 5.77 years [SD 3.82 years]; p < .01). Nonatopic individuals had more intensive esophageal acid exposure than atopic ones (Boix-Ochoa score 28.19 [SD 18.26] vs 18.26 [SD 12.84]; p < .048). The intensity of GER was also significantly correlated with frequent or difficult-to-control nighttime asthma attacks.

CONCLUSIONS

There are differences in clinical features of asthma in children with regard to the intensity of esophageal acid exposure. Symptoms of asthma in nonatopic individuals with early onset and difficult-to-control nighttime asthma attacks suggest the possibility of concomitant, clinically relevant GER.

Applying principles of physics to the airway to help explain the relationship between asthma and gastroesophageal reflux

Gastroesophageal reflux (GER) and asthma have been linked, but the true nature of this relationship is incompletely understood. Most of the literature examining this association has implicated GER as the factor contributing to asthma. GER has also been linked to conditions of the upper airway like sinusitis and obstructive sleep apnea (OSA), and once again, usually presumed to be the causative factor. While GER seems to be capable of exacerbating airway disease, mounting evidence suggests that airway obstruction is a risk factor for developing GER. This article examines the principles of physics that predict what should occur given the anatomy of the airway and the esophagus, and provides multiple examples of disease associations that appear to support the hypothesis that airway obstruction is a significant risk factor for development of gastroesophageal reflux.