Reliability and validity of the St George's Respiratory Questionnaire for asthma

Asthma phenotype: Clinical, physiological, and biochemical profiles of North Indian patients

Background and Objectives:

Asthma is a common, chronic and heterogeneous disease with various phenotypes. The clinical phenotypes has aided in revealing the genetic heterogeneity, provide education, life style advice and novel biological treatments. The few common factors associated with phenotypes are smoking, rhinitis and obesity. The present study was thus planned to analyse and correlate the clinical, physiological, biochemical and serological parameters of asthma and to study the phenotypic characteristics in different asthmatic.

Methods:

This was a prospective observational study of 120 patients with 30 each in BA-rhinitis, BA, BA-obesity and BA smoker phenotypes. All the enrolled patients were assessed by SGRQ, Mini-AQLQ, GINA with ACE, chest X ray, Spirometry, SPT against common aero-allergens, FENO, hsCRP, vitamin-D, IgE, and Interleukins (IL) including IL-5, IL-6, IL-8, IL-13, IL-17 and IL-33. The mentioned profiles of each phenotype correlated and characterized among different phenotypes.

Results:

The majority of patients 78(65%) were female with mean BMI of 24.07±4.73kg/m². Majority of the patient in BA and BA-rhinitis phenotype are in mild severity and young compared to majority in BA-obesity and BA-smoker are moderate to severe severity with older. (p<0.001) The SPT and FENO level were highest among BA-rhinitis phenotype with significant difference among phenotypes. (p<0.001) Similarly the most of inflammatory markers were significantly different in various phenotypes. The FEV1 showed correlation with most of parameters with statistically significant correlation with IL-5, IL-8 and FENO.

Conclusion:

The majority of parameters were significantly different among various phenotypes. We advise to phenotypic classification of asthma whenever possible for better management and quality of life.

Burden and socioeconomics of asthma, allergic rhinitis, atopic dermatitis and food allergy

INTRODUCTION

Asthma, allergic rhinitis, atopic dermatitis, and food allergy affect approximately 20% of the global population. Few studies describe the burden of the totality of these diseases and only a handful studies provide a comprehensive overview of the socioeconomic impact of these diseases.

AREAS COVERED

For this narrative review, we searched Pubmed using selected keywords and inspected relevant references using a snowballing process. We provide an overview of the socioeconomic burden of allergic diseases (in particular, asthma, allergic rhinitis, atopic dermatitis, and food allergy). The focus of this review is on their epidemiology (incidence, prevalence), burden (disability-adjusted life years, quality of life), and direct and indirect costs (absenteeism and presenteeism). We have put special emphasis on differences between countries.

EXPERT COMMENTARY

Both the prevalence and the burden of allergic diseases are considerable with prevalence varying between 1% and 20%. We identified a plethora of studies on asthma, but studies were generally difficult to compare due to the heterogeneity in measures used. There were only few studies on the burden of food allergy; therefore, more studies on this allergy are required. For future studies, we recommend standardizing epidemiologic, socioeconomic impact, and quality of life measures of allergic diseases.

Effect of Inspiratory Muscle Training in the Management of Patients With Asthma: A RANDOMIZED CONTROLLED TRIAL

PURPOSE

The aim of this study was to investigate the effects of inspiratory muscle training (IMT) on respiratory muscle strength, exercise capacity, dyspnea, fatigue, quality of life, and daily living activities of asthmatic patients.

METHODS

Thirty-eight asthmatic patients, between 18 and 65 years of age, were enrolled in the study and randomly divided into 2 groups; IMT (n = 20) or control (n = 18). Participants in the IMT group performed 30 breaths using a patient-specific threshold pressure device, twice daily for 6 wk at 50% maximal inspiratory pressure (MIP), in addition to "breathing training" during this period. Participants in the control group performed only the "breathing training" (sham or no threshold pressure device). Outcome measurements, performed before and after the intervention, included pulmonary function test, respiratory muscle strength, 6-min walk test, modified Medical Research Council dyspnea scale, St George's Respiratory Questionnaire, Fatigue Severity Scale, and London Chest Activity of Daily Living scale.

RESULTS

Among the outcomes in the study, changes to key variables including MIP (P < .01); MIP, percent predicted (P < .01); maximal expiratory pressure (MEP), percent predicted (P < .01); 6-min walk test walking distance (P = .001); modified Medical Research Council scale (P =<.001); Fatigue Severity Scale (P = .03); St George's Respiratory Questionnaire symptoms (P = .03); London Chest Activity of Daily Living domestic (P = .03); and London Chest Activity of Daily Living leisure (P = .01) were significantly different in favor of IMT versus control.

CONCLUSION

These findings suggest that IMT may be an effective modality to enhance respiratory muscle strength, exercise capacity, quality of life, daily living activities, reduced perception of dyspnea, and fatigue in asthmatic patients.

Reliability, validity and responsiveness of E-RS:COPD in patients with spirometric asthma-COPD overlap

BACKGROUND

The Evaluating Respiratory Symptoms in Chronic Obstructive Pulmonary Disease (E-RS:COPD) is a patient-reported diary that assesses respiratory symptoms in stable COPD.

METHODS

This post hoc analysis of a randomized, double-blind, parallel-arm trial (GSK ID: 200699; NCT02164539) assessed the structure, reliability, validity and responsiveness of the E-RS, and a separate wheeze item, for use in patients with a primary diagnosis of asthma or COPD, but with spirometric characteristics of both (fixed airflow obstruction and reversibility to salbutamol; a subset of patients referred to as spirometric asthma-COPD overlap [ACO]; N = 338).

RESULTS

Factor analysis demonstrated that E-RS included Cough and Sputum, Chest Symptoms, and Breathlessness domains, with a Total score suitable for quantifying overall respiratory symptoms (comparative fit index: 0.9), consistent with the structure shown in COPD. The wheeze item did not fit the model. Total and domain scores were internally consistent (Cronbach's alpha: 0.7-0.9) and reproducible (intra-class correlations > 0.7). Moderate correlations between RS-Total and RS-Breathlessness scores were observed with St George's Respiratory Questionnaire (SGRQ) Total and Activity domain scores at baseline (r = 0.43 and r = 0.48, respectively). E-RS scores were sensitive to change when a patient global impression of change and SGRQ change scores were used to define responders, with changes of ≥ - 1.4 in RS-Total score interpreted as clinically meaningful.

CONCLUSIONS

E-RS:COPD scores were reliable, valid and responsive in this sample, suggesting the measure may be suitable for evaluating the severity of respiratory symptoms and the effects of treatment in patients with asthma and COPD that exhibit spirometric characteristics of both fixed airflow obstruction and reversibility. Further study of this instrument and wheeze in new samples of patients with ACO is warranted.

Qualitative evaluation of the St George's Respiratory Questionnaire in patients with severe asthma

PURPOSE

Content validity is the extent to which a patient-reported outcome measure evaluates the concepts most relevant to a patient's condition and treatment. The St George's Respiratory Questionnaire (SGRQ) has been validated in a range of respiratory conditions. This study evaluated the content validity of the SGRQ in patients with severe asthma.

METHODS

A qualitative study, guided by a protocol, which included concept elicitation and cognitive debriefing of the SGRQ, was conducted in patients aged ≥18 years with history of severe asthma and blood eosinophil counts of ≥150/μL (past month) or ≥300/μL (past 12 months). Patients were recruited until saturation for concept elicitation was achieved (i.e. no additional concepts identified). Concepts identified by the patients were then mapped to the SGRQ.

RESULTS

18 patient interviews provided concept saturation. Concept elicitation confirmed that the SGRQ includes the commonly reported asthma symptoms and their impact on daily life. In total, 89-100% of patients routinely experienced cough, nighttime awakenings, shortness of breath, chest tightness, sleep difficulty, phlegm/mucus, and wheezing. Patients reported asthma impacting daily and physical activities, mood and sleep. Cognitive interviewing confirmed that patients understood the instructions, items and response options in the SGRQ. Nearly half of the concepts in the SGRQ were endorsed by ≥12 patients; of the 17 items with scoring weights ≥85, 11 were mentioned by ≥12 patients.

CONCLUSIONS

This study demonstrates that the SGRQ is a relevant, comprehensive and content-valid instrument to assess health status in patients with severe asthma.

Subtypes of asthma based on asthma control and severity: a latent class analysis

BACKGROUND

Asthma subtyping is a complex new field of study. Usually both etiological and outcome factors of asthma have been used simultaneously for subtyping thus making the interpretation of the results difficult. Identification of subtypes of asthma based on questionnaire data only will be useful for both treatment of asthma and for research. Our objective was to identify asthma subtypes that capture both asthma control and severity based on easily accessible variables.

METHODS

We applied latent class analysis for the 1995 adult asthmatics, 692 men and 1303 women, of the Northern Finnish Asthma Study (NoFAS). The classifying variables included use of asthma medication within the last 12 months, St. George's Respiratory Questionnaire score, and asthma-related healthcare use within the last 12 months. Covariates adjusted for included COPD, allergic rhinitis/allergic eczema, BMI, age and sex. All information was based on self-administered questionnaires.

RESULTS

We identified four subtypes for women: Controlled, mild asthma (41% of participants); Partly controlled, moderate asthma (24%); Uncontrolled asthma, unknown severity (26%), and Uncontrolled, severe asthma (9%). For men we identified three subtypes: Controlled, mild asthma (31%); Poorly controlled asthma, unknown severity (53%); and Partly controlled, severe asthma (17%). For almost 96% of the subjects this subtyping was accurate. The covariates fitted in the model were based on clinical judgment and were good predictors of class membership.

CONCLUSIONS

Our results show that it is possible to form meaningful and accurate asthma subtypes based on questionnaire data, and that separate classification should be applied for men and women.

Increased asthma risk and impaired quality of life after bronchiolitis or pneumonia in infancy

BACKGROUND

Recent studies have revealed that adulthood asthma has its origin in early childhood.

AIM

The aim of the present study was to evaluate the prevalence of asthma and respiratory health-related quality of life in adults 30 years after hospitalization for bronchiolitis or pneumonia in infancy.

METHODS

Patients who were hospitalized for bronchiolitis or pneumonia at age under 24 months in 1981-1982 have been followed in repeated visits. In 2010, 48 of the 83 former patients with bronchiolitis (57.8%), 22 of the 44 former patients with pneumonia (50.0%), and 138 matched controls participated in the clinical study at the age of 28-31 years. The participants completed a structured questionnaire on respiratory symptoms, the Saint George's Respiratory Questionnaire (SGRQ), and underwent 2-week peak expiratory flow (PEF) monitoring. Asthma was defined as doctor-diagnosed and self-reported asthma based on doctor-prescribed medication for asthma, the presence of asthma-presumptive symptoms, and the results of home PEF monitoring.

RESULTS

Both doctor-diagnosed asthma (31.3% vs. 10.9% adjusted P = 0.002) and self-reported asthma (35.4% vs. 14.5% 0.003), as well as repeated on-demand use of bronchodilators (35.4% vs. 14.5% 0.002), and regular use of inhaled corticosteroids (20.8% vs. 8.7% 0.023) were more common in former bronchiolitis patients than in controls. Former bronchiolitis and pneumonia patients had higher total SGRQ scores than controls. The median scores were 5.4 (IQ(25-75) 0.0-14.7, P < 0.001) in bronchiolitis group, 4.9 (1.3-14.8, 0.012) in pneumonia group compared to controls 1.5 (0.0-6.0).

CONCLUSION

Hospitalization for bronchiolitis in infancy is associated with an increased risk of asthma, and an increased use of asthma medication in adulthood at the age of 28-31 years. Impaired respiratory health-related quality of life in adulthood as measured by the SGRQ is present after bronchiolitis and pneumonia in infancy.