The forgotten message from gold: FVC is a primary clinical outcome measure of bronchodilator reversibility in COPD

Changes in Peak Inspiratory Flow After Acute Bronchodilation: An Observational Study of Patients with Stable Chronic Obstructive Pulmonary Disease

Introduction: Identifying factors influencing peak inspiratory flow (PIF) is essential for aerosol drug delivery in stable patients with chronic obstructive pulmonary disease. While a minimum PIF for dry powder inhalers (DPIs) is established, acute bronchodilator (BD) effects on PIF remain unknown. Materials and Methods: An inspiratory flow meter (In-Check™ DIAL) was used to measure PIF in stable patients during a 24-week observational cross-sectional study. Additionally, bronchodilator responsiveness (BDR) was determined using the In-Check DIAL device and spirometry. Patients received four puffs of albuterol, and pre- and post-BD PIF, forced expiratory volume in one second (FEV1), and forced vital capacity were measured. Sixty-three patients completed acute BDR data collection from July 31, 2019, to November 9, 2021. Primary endpoints were pre- and post-BD spirometry and PIF. Statistical analyses included PIF correlations with FEV1. BD change was assessed according to inhaler resistance and sex (subgroup analysis). Results: Median patient age was 64.8 years, 85.7% were non-Hispanic White, and 57.1% were female. The median increase in absolute PIF (In-Check DIAL) was 5.0 L/min, and the % PIF change was 8.9%. With albuterol, 57.1% experienced a PIF BD change >5.0%, whereas 49.2% experienced a change >10.0%. Similarly, 55.6% experienced an FEV1 BD change >5.0% and 28.6% had a >10.0% FEV1 BD change with albuterol. PIF was weakly correlated with FEV1 BD change (absolute; % PIF; r = 0.28 [p = 0.02]; r = 0.21 [p = 0.11]). Pre- and post-BD median PIF were 75.5 and 83.5 L/min for low-to-medium-resistance DPI and 45.0 and 52.0 L/min for high-resistance, respectively. The median increases in pre- and post-BD PIF were 9.0 L/min in males and 4.5 L/min in females. In contrast to when using the In-Check DIAL device, we observed no consistent bronchodilatory effects on PIF measured by spirometry. Conclusions: Using the In-Check DIAL device, ∼50% of patients experienced >10% PIF increase after acute BD, potentially enhancing medication lung deposition. Further research is required to understand PIF's impact on medication delivery. ClinicalTrials.gov Identifier: NCT04168775.

View Score: An early warning score to detect possible complications among COVID-19 patients

Introduction

Understanding pulmonary function at various phases after coronavirus disease 2019 (COVID-19) infection is critical for determining the exact pathophysiological mechanism of COVID-19.

Research Question

What is the correlation between spirometry indices and clinical indicators in COVID-19 patients over a 6-week follow-up?

Objectives

1) To assess deterioration or improvement in spirometry parameters including forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and ratio FEV1/FVC in COVID-19 patients. 2) To study the correlation between FVC, FEV1, and FEV1/FVC with oxygen saturation and clinical findings.

Materials and Methods

A prospective observational study was conducted for a 6-week period among 25, COVID-19 patients who were either asymptomatic or mildly symptomatic. Each patient received a home-use-connected spirometer-SpiroPRO®, a pulse oximeter, and a thermometer from Briota Technologies Pvt Ltd. (BRIOTA). Patients and healthcare professionals were given training for performing spirometry twice a day as well as access to mobile apps was provided. Spirometry indices, patient symptoms, and vital statistics were used to calculate the VIEW™ score using machine learning algorithms.

Result

The Bland-Altman plots showed that FEV1 reduced slightly up to 21-28 days and comes back to normal around 42 days. VIEW™ score increased up to day 21 and then decreased toward day 42. An increase in VIEW™ score increases the risk of COVID-19 complications. VIEW™ score and FEV1 showed a significant correlation.

Conclusion

Home-based spirometry acts as an effective tool for COVID-19 patients to predict lung complications and also promote self-monitoring thereby reducing the burden on the health system.

Differences in Pulmonary Function Improvement after Once-Daily LABA/LAMA Fixed-Dose Combinations in Patients with COPD

This real-world study evaluated the efficacy of once-daily long-acting β2-agonist (LABA)/long-acting muscarinic antagonist (LAMA) fixed-dose combinations (FDCs) for improving lung function in patients with chronic obstructive pulmonary disease (COPD). Patients with COPD who were treated with once-daily LABA/LAMA FDCs for 12 months were included. We evaluated their lung function improvement after 12 months of treatment with different LABA/LAMA FDCs. A total of 198 patients with COPD who were treated with once-daily LABA/LAMA FDCs were analyzed. A total of 114 patients were treated with umeclidinium/vilanterol (UMEC/VIL); 34 patients were treated with indacaterol/glycopyrronium (IND/GLY); and 50 patients were treated with tiotropium/olodaterol (TIO/OLO). The forced expiratory volume in 1 s (FEV1) was significantly increased in the patients treated with all three once-daily FDCs (55.2% to 60.9%, p = 0.012 for UMEC/VIL, 58.2% to 63.6%, p = 0.023 for IND/GLY, and 54.1% to 57.7%, p = 0.009 for TIO/OLO). The treatment of COPD patients with TIO/OLO resulted in a significant improvement in both forced vital capacity (FVC%) (71.7% to 77.9%, p = 0.009) and residual volume (RV%) (180.1% to 152.5%, p < 0.01) compared with those treated with UMEC/VIL (FVC%: 75.1% to 81.5%, p < 0.001; RV%:173.8% to 165.2%, p = 0.231) or IND/GLY (FVC%: 73.9% to 79.3%, p = 0.08; RV%:176.8% to 168.3%, p = 0.589). Patients treated with UMEC/VIL or TIO/OLO showed significant improvement in FVC. In addition, those receiving TIO/OLO also showed significant improvement in RV reduction.

The Prevalence of Bronchodilator Responsiveness "Asthma" Among Adult Indigenous Australians Referred for Lung Function Testing in the Top End Northern Territory of Australia

Background

Among Indigenous Australians, studies examining the clinical significance of airway bronchodilator responsiveness (BDR) are limited. In this retrospective study, we examined the nature of underlying lung disease in adult Indigenous patients with BDR referred for lung function testing (LFT) in the Top End Health Service region of the Northern Territory of Australia.

Methods

Presence or absence of BDR as per usual (FVC or FEV₁ change pre to post ≥12% and ≥0.2L) and updated (2021 ">10% predicted) ATS/ERS criteria among Indigenous and non-Indigenous Australians was determined. The radiological findings in the Indigenous study participants with and without BDR were next assessed for the presence of underlying chronic airway/lung disease.

Results

We found that 123/742 (17%) Indigenous and 578/4579 (13%) non-Indigenous patients had a significant BDR. Indigenous patients with BDR were younger (mean difference 7 years), with a greater proportion of females (52 vs 32%), underweight (15 vs 4%) and current smokers (52 vs 25%). Indigenous patients with BDR displayed lower LFT values, and a higher proportion exhibited FVC BDR compared to non-Indigenous (34 vs 20%). Almost half (46%) of Indigenous patients with BDR had evidence of COPD and/or bronchiectasis on radiology. Adjusting for the presence of radiologic or spirometric evidence of COPD, the presence of BDR was similar between Indigenous and non-Indigenous patients (5-8 vs 7-11%), irrespective of which BDR criteria was used.

Conclusion

BDR was higher overall among Indigenous in comparison to non-Indigenous patients; however, a significant proportion of Indigenous patients demonstrating BDR had evidence of underlying COPD/bronchiectasis. This study highlights that although presence of BDR among Indigenous people may indicate asthma, it may also be observed among patients with COPD/bronchiectasis or could represent asthma/COPD/bronchiectasis overlap. Hence, a combination of clinical history, LFT and radiology should be considered for precise diagnosis of lung disease in this population.

The global lung function initiative 2021 (GLI-2021) norms provide mixed results for static lung volumes (SLVs) in Algerian adults

The validity of the GLI-2021 norms for SLVs in healthy Algerian adults has not been assessed. To ascertain how well do the GLI-2021 norms fit to contemporary SLVs data in Algerian adults. This was a cross-sectional study involving 481 (n = 242 females) healthy non-smoking adults recruited from the Algiers general population. All participants underwent a clinical examination and a plethysmography. Z-scores for slow vital capacity (SVC), functional residual capacity (FRC), residual volume (RV), total lung capacity (TLC), expiratory reserve volume (ERV), inspiratory capacity (IC), and RV/TLC were calculated. The mean difference between the determined and the predicted values (∆value) of SLVs were calculated. The GLI-2021 norms would be considered as reflective of contemporary Algerian SLVs if the total sample mean z-scores were in the normal range (ie; −0.5 to +0.5). The participants’ means ± SDs of age and height were 46.4 ± 16.4 years and 166 ± 10 cm, respectively. The determined SLVs were significantly different from those predicted (∆values means ± SDs were −170 ± 470 ml for IC, −100 ± 490 ml for SVC, 170 ± 400 ml for ERV, 240 ± 620 ml for TLC, 370 ± 340 ml for RV, 480 ± 480 ml for FRC, and 5.28 ± 4.38% for RV/TLC). The means ± SDs z-scores for IC, SVC, ERV, and TLC were in the normal range (−0.29 ± 0.88, −0.17 ± 0.94, 0.29 ± 0.77, and 0.35 ± 0.86, respectively), but those of RV, FRC, and RV/TLC were out of the normal range (0.74 ± 0.66, 0.75 ± 0.72, and 0.83 ± 0.75, respectively). In healthy Algerian adults, the GLI-2021 norms fit well to SVC, TLC, ERV, and IC, but they do not fit to FRC, RV, and RV/TLC.

Respiratory Effects of Treatment with a Glucagon-Like Peptide-1 Receptor Agonist in Patients Suffering from Obesity and Chronic Obstructive Pulmonary Disease

Purpose

Chronic obstructive pulmonary disease (COPD) affects millions of people worldwide. Obesity is commonly seen concomitantly with COPD. People with COPD have reduced quality of life, reduced physical activity, chronic respiratory symptoms, and may suffer from frequent clinical exacerbations. Liraglutide is a glucagon-like peptide-1 receptor agonist (GLP-1RA) approved for weight loss and treatment of type-2 diabetes mellitus. In addition, liraglutide exerts anti-inflammatory actions by reducing IL-6 and MCP-1 levels. We investigated the effect of liraglutide on pulmonary function in people suffering from obesity and COPD.

Patients and Methods

In this controlled, double-blind trial, 40 people with obesity and COPD from two outpatient clinics were allocated randomly to receive liraglutide (3.0 mg, s.c.) or placebo (s.c.) for 40 weeks. At baseline and after 4, 20, 40, and 44 weeks, participants underwent pulmonary-function tests, 6-min walking test, and replied to a questionnaire regarding the clinical impact of COPD (COPD assessment test (CAT)-score).

Results

Compared with placebo, liraglutide use resulted in significant weight loss, increased forced vital capacity (FVC) and carbon monoxide diffusion capacity, and improved CAT-score. We found no significant changes in forced expiratory volume in one second (FEV₁), FEV₁/FVC, or 6-min walking distance.

Conclusion

In patients suffering from obesity and COPD, 40 weeks of treatment with liraglutide improved some measures of pulmonary function. Our study suggests that liraglutide at 3.0 mg may be appropriate treatment in patients with obesity and COPD.

Diagnostic performance of lung volumes in assessment of reversibility in chronic obstructive pulmonary disease

Background

Reversibility measured by spirometry in chronic obstructive pulmonary disease (COPD) is defined as an increase in forced expiratory volume in first second (FEV1) that is both more than 12% and 200 mL above the pre-bronchodilator value in response to inhaled bronchodilators. FEV1 only may not fully reverberate the changes caused by reduction in air trapping or hyperinflation. To date, the studies that examined the effect of inhaled bronchodilators (BD) on residual volume (RV) and total lung capacity (TLC) are limited. This study was carried out to assess the differences between flow and volume responses after bronchodilator reversibility testing in patients with different COPD GOLD stages (GOLD stage I to stage IV). Spirometry and whole body plethysmography were done before and 15 min after inhalation of 400 μg salbutamol.

Results

Majority (53.3%) of cases were volume responders, 18.7% were flow responders, 20% were flow and volume responders, and 8% were non responders. Significant increase in Δ FEV1% was found in 15% of cases while 55% showed a significant increase in Δ FVC (P= < 0.001). Mean difference of Δ FVC (L) post BD was significantly increased with advancing GOLD stage (P= 0.03). A cutoff point > 20% for Δ RV% had 70% sensitivity and 60% specificity and > 12% for Δ TLC% showed 90% sensitivity and 45% specificity for prediction of clinically significant response to BD based on FEV1. A cutoff point > 18% for Δ RV% had 78% sensitivity and 29% specificity and > 14% for Δ TLC% had 50% sensitivity and 70% specificity for prediction of clinically significant response to BD based on FVC.

Conclusion

ΔFEV1 underestimates the true effect of bronchodilators with advancing GOLD stage. Measurement of lung volumes in addition to the standard spirometric indices is recommended when determining bronchodilator response in COPD patients.

Combined Forced Expiratory Volume in 1 Second and Forced Vital Capacity Bronchodilator Response, Exacerbations, and Mortality in Chronic Obstructive Pulmonary Disease

Rationale: The American Thoracic Society (ATS)/European Respiratory Society defines a positive bronchodilator response (BDR) by a composite of BDR in either forced expiratory volume in 1 second (FEV₁) and/or forced vital capacity (FVC) greater than or equal to 12% and 200 ml (ATS-BDR). We hypothesized that ATS-BDR components would be differentially associated with important chronic obstructive pulmonary disease (COPD) outcomes. Objectives: To examine whether ATS-BDR components are differentially associated with clinical, functional, and radiographic features in COPD. Methods: We included subjects with COPD enrolled in the COPDGene study. In the main analysis, we excluded subjects with self-reported asthma. We categorized BDR into the following: 1) No-BDR, no BDR in either FEV₁ or FVC; 2) FEV₁-BDR, BDR in FEV₁ but no BDR in FVC; 3) FVC-BDR, BDR in FVC but no BDR in FEV₁; and 4) Combined-BDR, BDR in both FEV₁ and FVC. We constructed multivariable logistic, linear, zero-inflated negative binomial, and Cox hazards models to examine the association of BDR categories with symptoms, computed tomography findings, change in FEV₁ over time, respiratory exacerbations, and mortality. We also created models using the ATS BDR definition (ATS-BDR) as the main independent variable. Results: Of 3,340 COPD subjects included in the analysis, 1,083 (32.43%) had ATS-BDR, 182 (5.45%) had FEV₁-BDR, 522 (15.63%) had FVC-BDR, and 379 (11.34%) had Combined-BDR. All BDR categories were associated with FEV₁ decline compared with No-BDR. Compared with No-BDR, both ATS-BDR and Combined-BDR were associated with higher functional residual capacity %predicted, greater internal perimeter of 10 mm, and greater 6-minute-walk distance. In contrast to ATS-BDR, Combined-BDR was independently associated with less emphysema (adjusted beta regression coefficient, -1.67; 95% confidence interval [CI], -2.68 to -0.65; P = 0.001), more frequent respiratory exacerbations (incidence rate ratio, 1.25; 95% CI, 1.03-1.50; P = 0.02) and severe exacerbations (incidence rate ratio, 1.34; 95% CI, 1.05-1.71; P = 0.02), and lower mortality (adjusted hazards ratio, 0.76; 95% CI, 0.58-0.99; P = 0.046). Sensitivity analysis that included subjects with self-reported history of asthma showed similar findings. Conclusions: BDR in both FEV₁ and FVC indicates a COPD phenotype with asthma-like characteristics, and provides clinically more meaningful information than current definitions of BDR.

How to Stage Airflow Limitation in Stable Chronic Obstructive Pulmonary Disease Male Patients?

No study has evaluated the utility of different classifications of chronic obstructive pulmonary disease (COPD) airflow limitation (AFL) in terms of the refined “ABCD” classification of the Global Initiative for Chronic Obstructive Lung Disease (GOLD) or in terms of the impacts on quality of life. This study aimed to compare some relevant health outcomes (i.e., GOLD classification and quality-of-life scores) between COPD patients having “light” and “severe” AFL according to five COPD AFL classifications. It was a cross-sectional prospective study including 55 stable COPD male patients. The COPD assessment test (CAT), the VQ11 quality-of-life questionnaire, a spirometry, and a bronchodilator test were performed. The patients were divided into GOLD “A/B” and “C/D.” The following five classifications of AFL severity, based on different post-bronchodilator forced expiratory volume in 1 s (FEV₁) expressions, were applied: FEV_1%pred: “light” (≥50), “severe” (<50); FEV_1z-score: “light” (≥−3), “severe” (<−3); FEV₁/height²: “light” (≥0.40), “severe” (<0.40); FEV₁/height³: “light” (≥0.29), “severe” (<0.29); and FEV_1Quotient: “light” (≥2.50), “severe” (<2.50). The percentages of the patients with “severe” AFL were significantly influenced by the applied classification of the AFL severity (89.1 [FEV_1z-score], 63.6 [FEV_1%pred], 41.8 [FEV₁/height³], 40.0 [FEV_1Quotient], and 25.4 [FEV₁/height²]; Cochrane test = 91.49, df = 4). The CAT and VQ11 scores were significantly different between the patients having “light” and “severe” AFL. In GOLD “C/D” patients, only the FEV_1Quotient was able to distinguish between the two AFL severities. To conclude, the five classifications of COPD AFL were not similar when compared with regard to some relevant health outcomes.

Clinical Significance of Bronchodilator Responsiveness Evaluated by Forced Vital Capacity in COPD: SPIROMICS Cohort Analysis

Objective

Bronchodilator responsiveness (BDR) is prevalent in COPD, but its clinical implications remain unclear. We explored the significance of BDR, defined by post-bronchodilator change in FEV₁ (BDR_FEV1) as a measure reflecting the change in flow and in FVC (BDR_FVC) reflecting the change in volume.

Methods

We analyzed 2974 participants from a multicenter observational study designed to identify varying COPD phenotypes (SPIROMICS). We evaluated the association of BDR with baseline clinical characteristics, rate of prospective exacerbations and mortality using negative binomial regression and Cox proportional hazards models.

Results

A majority of COPD participants exhibited BDR (52.7%). BDR_FEV1 occurred more often in earlier stages of COPD, while BDR_FVC occurred more frequently in more advanced disease. When defined by increases in either FEV₁ or FVC, BDR was associated with a self-reported history of asthma, but not with blood eosinophil counts. BDR_FVC was more prevalent in subjects with greater emphysema and small airway disease on CT. In a univariate analysis, BDR_FVC was associated with increased exacerbations and mortality, although no significance was found in a model adjusted for post-bronchodilator FEV₁.

Conclusion

With advanced airflow obstruction in COPD, BDR_FVC is more prevalent in comparison to BDR_FEV1 and correlates with the extent of emphysema and degree of small airway disease. Since these associations appear to be related to the impairment of FEV₁, BDR_FVC itself does not define a distinct phenotype nor can it be more predictive of outcomes, but it can offer additional insights into the pathophysiologic mechanism in advanced COPD.

Clinical trials registration

ClinicalTrials.gov: NCT01969344T4.

A New Bronchodilator Response Grading Strategy Identifies Distinct Patient Populations

Rationale: A positive bronchodilator response (BDR) according to American Thoracic Society/European Respiratory Society (ATS/ERS) guidelines require both 200 ml and 12% increase in forced expiratory volume in 1 second (FEV1) or forced vital capacity (FVC) after bronchodilator inhalation. This dual criterion is insensitive in those with high or low FEV1.Objectives: To establish BDR criteria with volume or percentage FEV1 change.Methods: The largest FEV1 and FVC were identified from three pre- and three post-bronchodilator maneuvers in COPDGene (Genetic Epidemiology of COPD) participants. A total of 7,741 individuals with coefficient of variation less than 15% for both FEV1 and FVC formed bronchodilator categories of FEV1 response: negative (≤0.00% or ≤0.00 L), minimal (>0.00% to ≤9.00% or >0.00 L to ≤0.09 L), mild (>9.00% to ≤16.00% or >0.09 L to ≤0.16 L), moderate (>16.00% to ≤26.00% or >0.16 L to ≤0.26 L), and marked (>26.00% or >0.26 L). These response size categories are based on empirical limits considering average FEV1 increase of approximately 160 ml and the clinically important difference for FEV1. To compare flow and volume response characteristics, BDR-FEV1 category assignments were applied for the BDR-FVC response.Results: Twenty percent met mild and 31% met moderate or marked BDR-FEV1 criteria, whereas 12% met mild and 33% met moderate or marked BDR-FVC criteria. In contrast, only 20.6% met ATS/ERS positive criteria. Compared with the negative BDR-FEV1 category, the minimal, mild, moderate, and marked BDR-FEV1 categories were associated with greater 6-minute-walk distance and lower St. George's Respiratory Questionnaire and modified Medical Research Council dyspnea scale scores. Compared with negative BDR, moderate and marked BDR-FEV1 categories were associated with fewer exacerbations, and minimal BDR was associated with lower computed tomography airway wall thickness. Compared with the negative category, all BDR-FVC categories were associated with increasing emphysema percentage and gas trapping percentage. Moderate and marked BDR-FVC categories were associated with higher St. George's Respiratory Questionnaire scores but fewer exacerbations and lower dyspnea scores.Conclusions: BDR grading by FEV1 volume or percentage response identified subjects otherwise missed by ATS/ERS criteria. BDR grades were associated with functional exercise performance, quality of life, exacerbation frequency, dyspnea, and radiological airway measures. BDR grades in FEV1 and FVC indicate different clinical and radiological characteristics.

The Effects of Ramadan-Fasting (RF) on Inflammatory and Hematological Indices of Stable Chronic Obstructive Pulmonary Disease (COPD) Male Patients: A Pilot Study

No previous study has evaluated the effects of RF on inflammatory and hematological indices of COPD patients. The main objective of the present pilot study was to assess the effects of RF on some inflammatory and hematological indices measured in male patients with stable COPD. Fifteen COPD patients (mean ± SD of age: 71 ± 6 years) who fasted during Ramadan 2017 volunteered for the study. Three sessions (Before-Ramadan, End-Ramadan and After-Ramadan) were selected. Spirometry tests and blood samples were consistently performed 2.5-4.5 hr before the interruption of the fasting. Assessment sessions comprised: spirometry, inflammatory [erythrocyte sedimentation rate (ESR); C-reactive protein (CRP)] and hematological [red and white blood cells (RBC, WBC); hemoglobin; hematocrit; mean corpuscular volume; mean corpuscular hemoglobin; platelets] indices. Findings were analyzed by applying Friedman ANOVA. The median (lower-upper quartiles) of ESR (Before-Ramadan: 3 (2-9), End-Ramadan: 7 (0-13), After-Ramadan: 9 (5-15) mm/h) and CRP (Before-Ramadan: 20 (11-38), End-Ramadan: 15 (9-34), After-Ramadan: 20 (12-46) mg/L) were not significantly affected by RF. Among all the hematological indices, RF influenced only hemoglobin (Before-Ramadan: 14.4 ± 2.2, End-Ramadan: 13.4 ± 1.3, After-Ramadan: 12.2 ± 0.9 g/dL), hematocrit (Before-Ramadan: 45 ± 7, End-Ramadan: 40 ± 4, After-Ramadan: 39 ± 4%), RBC (Before-Ramadan: 5.1 ± 1.0, End-Ramadan: 4.6 ± 0.7, After-Ramadan: 4.4 ± 0.5 10⁶/mm³) and WBC (Before-Ramadan: 8,673 ± 1,911, End-Ramadan: 7,840 ± 1,526, After-Ramadan: 9,507 ± 2,190/mm³). Compared to the Before-Ramadan session, the End-Ramadan session values for hemoglobin, hematocrit, RBC and WBC were lower. Compared to the After-Ramadan session, the End-Ramadan session values for hemoglobin and WBC were higher and lower, respectively. In conclusion, RF caused significant reduction in hemoglobin, hematocrit, RBC and WBC. However, it did not induce any significant changes in the CRP and ESR indices.

The multi-ethnic global lung initiative 2012 (GLI-2012) norms reflect contemporary adult's Algerian spirometry

Background

The validation of the multi-ethnic GLI-2012 spirometric norms has been debated in several countries. However, its applicability in Algeria has not been verified.

Aim

To ascertain how well the GLI-2012 norms fit contemporary adult Algerian spirometric data.

Methods

This was a cross-sectional study of a convenience sample of 300 healthy non-smoker adults (50% men, age range: 18–85 years) recruited from the Algiers region general population. All participants underwent a clinical examination and a plethysmography measurement. Z-scores for some spirometric data [FEV₁, FVC, FEV₁/FVC and forced expiratory flow at 25–75% of FVC (FEF_25-75%)] were calculated. If the average Z-score deviated by “< ± 0.5” from the overall mean, the GLI-2012 norms would be considered as reflective of contemporary Algerian spirometry.

Results

The means±SDs of age, height, weight, FVC, FEV₁, FEV₁/FVC and FEF_25-75% of the participants were, respectively, 48±17 years, 1.65±0.10 m, 73±14 kg, 4.04±1.04 L, 3.18±0.82 L, 0.79±0.05 and 4.09±1.09 L/s. Almost the quarter of participants were obese. The total sample means±SDs Z-scores were 0.22±0.87 for FVC, 0.04±0.88 for FEV₁, -0.34±0.67 for FEV₁/FVC and 0.93±0.79 for FEF_25-75%. For men and women, only the means±SDs of the FEF_25-75% Z-scores exceeded the threshold of “± 0.5”, respectively, 1.13±0.77 and 0.73±0.76.

Conclusion

Results of the present study, performed in an Algerian population of healthy non-smoking adults, supported the applicability of the GLI-2012 norms to interpret FEV₁, FVC and FEV₁/FVC but not the FEF_25-75%.

The Effects of Ramadan Intermittent Fasting (RIF) on Spirometric Data of Stable COPD Patients: A Pilot Study

No previous study has raised the effects of RIF on lung function data of chronic obstructive pulmonary disease (COPD) patients. The objective of the present study was to assess the effects of RIF on spirometric data measured in male patients with a stable COPD. Sixteen patients with stable COPD (mean ± SD of age: 64 ± 7 years) who fasted during Ramadan volunteered to the study. Three sessions (Before-R, End-R, and After-R) were selected for spirometry tests that were consistently performed 2.5-4.5 hr before fasting break. Assessment sessions comprised: forced vital capacity (FVC), 1st s forced expiratory volume (FEV₁), FEV₁/FVC, peak expiratory flow (PEF), maximal mid-expiratory flow (MMEF), and forced expiratory flow rate at the x% of FVC to be exhaled (FEFx%). A reversibility test was performed only during the Before-Ramadan session. Spirometric data were expressed in percentages of local reference values. Findings were analyzed by applying repeated measures analysis of variance. The mean ± SD of the postbronchodilator FEV₁/FVC ratio and the FEV₁ were, respectively, 0.52 ± 0.14 and 48 ± 19%. The mean ± SD of FEV₁ (Before-R: 47 ± 19, End-R: 45 ± 18, After-R: 44 ± 19%), FVC (Before-R: 73 ± 18, End-R: 71 ± 16, After-R: 69 ± 17%), FEV₁/FVC (Before-R: 67 ± 16, End-R: 66 ± 16, After-R: 65 ± 16%), PEF (Before-R: 46 ± 19, End-R: 47 ± 22, After-R: 45 ± 21%), MMEF (Before-R: 19 ± 10, End-R: 18 ± 8, After-R: 18 ± 9%), FEF_25% (Before-R: 16 ± 6, End-R: 16 ± 5, After-R: 15 ± 5%), FEF_50% (Before-R: 21 ± 14, End-R: 20 ± 12, After-R: 20 ± 12%) and FEF_75% (Before-R: 27 ± 19, End-R: 27 ± 19, After-R: 27 ± 19%) were not significantly influenced by RIF. RIF did not bring about any significant changes in the spirometric data of stable COPD male patients fasting the 2016 holy month of Ramadan.

[Evaluation of quality of life (QOL) of Tunisians patients with COPD]

AIM

To test the Arabic version of the St. George's Hospital Respiratory Questionnaire (SGRQ) in stable Tunisian COPD patients.

HYPOTHESES

A correlation coefficient between the post-bronchodilator FEV1 and the "Total" score of SGRQ higher than "-0.40", and QOL scores lower in COPD with "mild to moderate airway obstruction" than in those with "severe to very severe airway obstruction" will be in favor of a possible application of the Arabic version of the SGRQ in Tunisians COPD patients.

METHODS

This is a prospective cross-sectional study including 50 clinically stable COPD patients. The Arabic version of the SGRQ was used. Four scores were calculated for the "Symptoms", "Activities", "Impacts" and "Total" components. Patients were divided into two groups according to the severity of their airway obstruction: "mild to moderate, n=30" and "severe to very severe, n=20". The correlation between the QOL "Total" score and postBD FEV1 was evaluated.

RESULTS

The mean±SD of age, cigarette smoking and post-bronchodilator FEV1 were, respectively, 60±10, 61±36 pack-years and 55±20 %. The correlation between the post-bronchodilator FEV1 and QOL "Total" score was significant at "-0.65". "Symptoms", "Activities", "Impacts" and "Total" scores were significantly less altered in patients with "mild to moderate airway obstruction" than among those with "severe to very severe airway obstruction" (respectively, 52±24 vs. 77±17, 66±28 vs. 87±18, 48±25 vs. 70±23 and 54±22 vs. 76±17).

CONCLUSION

The application of the Arabic version of the SGRQ in stable COPD patients gives reliable results.

Defining obstructive ventilatory defect in 2015

INTRODUCTION

There is no clear consensus as to what constitutes an obstructive ventilatory defect (OVD): Is it FEV1/FVC

AIM

To determine, according to the two definitions, the percentage of subjects having an OVD among them explored in a lung function exploration laboratory.

POPULATION AND METHODS

This is a retrospective study including 4,730 subjects aged 17-85 years. Subjects were divided according to the presence [physio (+) or operat (+)] or absence [physio (-) or operat (-)] of an OVD, and into younger (<45 years, n=2,076), older (≥45 years, n=2,654), smokers (n=1,208), and non-smokers (n=3,522) groups.

RESULTS

For the total sample, the younger and older groups [mean±SD of age (years), respectively, 46.7±14.1; 33.9±7.4, and 56.8±9.1], the 'physiological definition' detected, respectively, 13.46, 43.22, and 5.09% more OVD than the 'operational one' (p<0.05). In addition, the operational definition, compared with the physiological one, overdiagnosed OVD in 2.33 and 0.44% of smokers and non-smokers, respectively, and underdiagnosed it in 4.46% and 29.72% of smokers and non-smokers, respectively (p<0.05). Compared with the group 'physio (-), operat (+)', the 'physio (+), operat (-)' one was younger (74.2±4.7 years vs. 40.9±10.3 years) and had significantly higher FEV1 (62±13% vs. 78±17%) and FVC (71±15% vs. 93±19%).

CONCLUSION

The frequency of OVD much depends on the criteria used for its definition.

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Key Words

• FEV1/FVC
• fixed threshold
• guideline
• lower limit of normal
• obstructive ventilatory defect
• spirometry

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MESH Headings

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Female
• Forced Expiratory Volume
• Humans
• Male
• Middle Aged
• Pulmonary Disease, Chronic Obstructive/diagnosis
• Pulmonary Disease, Chronic Obstructive/epidemiology
• Pulmonary Disease, Chronic Obstructive/physiopathology
• Respiratory Function Tests
• Retrospective Studies
• Smoking/adverse effects
• Smoking/physiopathology
• Spirometry/methods
• Tunisia/epidemiology
• Vital Capacity

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Affiliation(s)

Zied Affes Department of Physiology and Functional Exploration, Farhat HACHED University Hospital of Sousse, Sousse, Tunisia
Salaheddine Rekik Department of Physiology and Functional Exploration, Farhat HACHED University Hospital of Sousse, Sousse, Tunisia
Helmi Ben Saad Department of Physiology and Functional Exploration, Farhat HACHED University Hospital of Sousse, Sousse, Tunisia Laboratory of Physiology, Faculty of Medicine of Sousse, University of Sousse, Sousse, Tunisia Research Laboratory N° LR14ES05: Interactions of the Cardiopulmonary System, Faculty of Medicine of Sousse, University of Sousse, Sousse, Tunisia;

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Small airway dysfunction and flow and volume bronchodilator responsiveness in patients with chronic obstructive pulmonary disease

Background

We investigated whether a relationship between small airways dysfunction and bronchodilator responsiveness exists in patients with chronic obstructive pulmonary disease (COPD).

Methods

We studied 100 (20 female; mean age: 68±10 years) patients with COPD (forced expiratory volume in 1 second [FEV₁]: 55% pred ±21%; FEV₁/forced vital capacity [FVC]: 53%±10%) by impulse oscillometry system. Resistance at 5 Hz and 20 Hz (R5 and R20, in kPa·s·L⁻¹) and the fall in resistance from 5 Hz to 20 Hz (R5 – R20) were used as indices of total, proximal, and peripheral airway resistance; reactance at 5 Hz (X5, in kPa·s·L⁻¹) was also measured. Significant response to bronchodilator (salbutamol 400 μg) was expressed as absolute (≥0.2 L) and percentage (≥12%) change relative to the prebronchodilator value of FEV₁ (flow responders, FRs) and FVC (volume responders, VRs).

Results

Eighty out of 100 participants had R5 – R20 >0.03 kPa·s·L⁻¹ (> upper normal limit) and, compared to patients with R5 – R20 ≤0.030 kPa·s·L⁻¹, showed a poorer health status, lower values of FEV₁, FVC, FEV₁/FVC, and X5, along with higher values of residual volume/total lung capacity and R5 (P<0.05 for all comparisons). Compared to the 69 nonresponders and the 8 FRs, the 16 VRs had significantly higher R5 and R5 – R20 values (P<0.05), lower X5 values (P<0.05), and greater airflow obstruction and lung hyperinflation.

Conclusion

This study shows that peripheral airway resistance is increased in the vast majority of patients with COPD, who showed worse respiratory reactance, worse spirometry results, more severe lung hyperinflation, and poorer health status. Small airway dysfunction was also associated with the bronchodilator responsiveness in terms of FVC, but not in terms of FEV₁.

Oxidative stress and lung function profiles of male smokers free from COPD compared to those with COPD: a case-control study

BACKGROUND

The mechanisms of smoking tobacco leading to chronic obstructive pulmonary disease (COPD) are beginning to be understood. However, conclusions about the role of blood or lung oxidative stress markers were disparate.

AIMS

To investigate the oxidative stress in blood or lung associated with tobacco smoke and to evaluate its effect on pulmonary function data and its relation with physical activity.

METHODS

It is a case-control study. Fifty-four male-smokers of more than five pack-years (PY) and aged 40-60 years were included (29 Non-COPD, 16 COPD). Physical activity score was determined. Blood sample levels of malondialdehyde (MDA), protein-cys-SH (PSH), and Glutathione (GSH) were measured. Fractional exhaled nitric oxide (FeNO) and plethysmographic measurements were performed. Correlation coefficients (r) evaluated the association between oxidative stress markers and independent variables (plethysmographic data and physical activity score).

RESULTS

Non-COPD (48 ± 6 years) and COPD (49 ± 5 years) groups had similar tobacco consumption patterns, that is, 27 ± 14 PY versus 30 ± 19 PY, respectively. Compared to the Non-COPD group, the COPD group had significantly lower levels of GSH and PSH, that is, mean ± SE were 40 ± 6 versus 25 ± 5 µg/mL and 54 ± 10 versus 26 ± 5 µg/g of hemoglobin, respectively. However, MDA level and FeNO values were similar. In the COPD group, none of the oxidative stress markers was significantly correlated with plethysmographic data or physical activity score. In the Non-COPD group, GSH was significantly correlated with physical activity score (r = 0.47) and PSH was significantly correlated with total lung capacity (TLC) (r = -0.50), residual volume (r = 0.41), and physical activity score (r = 0.62). FeNO was significantly correlated with TLC of the COPD group (r = -0.48).

CONCLUSION

Compared to the Non-COPD group, the COPD group had a marked decrease in blood antioxidant markers (GSH and PSH) but similar blood oxidant (MDA) or lung (FeNO) burden.

What is the difference between FEV1 change in percentage predicted value and change over baseline in the assessment of bronchodilator responsiveness in patients with COPD?

BACKGROUND

Several criteria are clinically applied in the assessment of significant bronchodilator responsiveness in chronic obstructive pulmonary disease (COPD). The present study aimed to investigate the differences in various degree of severity of COPD among these criteria.

METHODS

After 400 micrograms of salbutamol administered via spacer by metered dose inhaler (MDI), forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) changes (including percentage change, absolute change and absolute change in percentage predicted value) were retrospectively analysed in 933 stable patients with mild-to-very-severe COPD. Significant bronchodilator responsiveness was assessed using American Thoracic Society and European Respiratory Society (ATS-ERS) criterion based on FEV1 or/and FVC (both ≥12% increase over baseline and ≥200 mL) and FEV1 percentage predicted criterion (≥10% absolute increase in percentage predicted FEV1) in different grades of COPD.

RESULTS

Of the patients [age 66.8 years, baseline FEV1 974 mL (39.3% predicted) and FVC 2,242 mL], mean improvements were 126 mL in FEV1 and 265 mL in FVC; 21.4% and 45.3% met ATS-ERS criterion based on FEV1 and FVC, respectively; and 13.5% met FEV1 percentage predicted criterion. The responsive ratios of ATS-ERS criterion based on FEV1 to FEV1 percentage predicted criterion in grade I, II, III and IV of COPD were 0.95(:)1.26(:)2.53(:)6.00, respectively (P<0.01 in grade II and P<0.001 in grade III). As the degree of severity increased, the mean improvement of FEV1 was reduced; on the contrary, that of FVC was increased.

CONCLUSIONS

Compared with FEV1 percentage predicted criterion, ATS-ERS criterion based on FEV1 as well as FVC, the later in particular, detected a larger percentage of patients with significant responsiveness. The increasing difference was relevant as a function of the severity of airflow obstruction.

Bronchodilator responsiveness and reported respiratory symptoms in an adult population

BACKGROUND

The relationship between patient-reported symptoms and objective measures of lung function is poorly understood.

AIM

To determine the association between responsiveness to bronchodilator and respiratory symptoms in random population samples.

METHODS

4669 people aged 40 years and older from 8 sites in Canada completed interviewer-administered respiratory questionnaires and performed spirometry before and after administration of 200 ug of inhaled salbutamol. The effect of anthropometric variables, smoking exposure and doctor-diagnosed asthma (DDA) on bronchodilator responsiveness in forced expiratory volume in 1 second (FEV1) and in forced vital capacity (FVC) were evaluated. Multiple logistic regression was used to test for association between quintiles of increasing changes in FEV1 and in FVC after bronchodilator and several respiratory symptoms.

RESULTS

Determinants of bronchodilator change in FEV1 and FVC included age, DDA, smoking, respiratory drug use and female gender [p<0.005 to p<0.0001 ]. In subjects without doctor-diagnosed asthma or COPD, bronchodilator response in FEV1 was associated with wheezing [p for trend<0.0001], while bronchodilator response for FVC was associated with breathlessness. [p for trend <0.0001].

CONCLUSIONS

Bronchodilator responsiveness in FEV1 or FVC are associated with different respiratory symptoms in the community. Both flow and volume bronchodilator responses are useful parameters which together can be predictive of both wheezing and breathlessness in the general population.

Bronchodilator reversibility in COPD

COPD is a preventable and treatable disease characterized by airflow limitation that is not fully reversible. The diagnosis of COPD is based on spirometric evidence of airways obstruction following bronchodilator administration. Although it used to be commonly believed that patients with COPD have largely irreversible airflow obstruction, evidence now suggests that a considerable proportion of patients exhibit clinically significant bronchodilator reversibility. The complexity and inherent variability of a patient's acute response to a bronchodilator and the lack of a standardized procedure for assessing bronchodilator reversibility have led to significant confusion surrounding this concept. Although bronchodilator reversibility commonly is defined based on thresholds for improvement in FEV(1), lung volume-based measures of pulmonary function may be of particular importance in patients with severe COPD. The usefulness of acute reversibility to short-acting bronchodilators in predicting a patient's long-term response to bronchodilator maintenance therapy is also unclear, although most studies suggest that a lack of acute response to short-acting bronchodilators does not preclude a beneficial long-term response to maintenance bronchodilator treatment. This review outlines recent findings about the prevalence and usefulness of bronchodilator reversibility in patients with COPD based on the available literature and proposes areas of future research.

Functional imaging using computer methods to compare the effect of salbutamol and ipratropium bromide in patient-specific airway models of COPD

BACKGROUND

Salbutamol and ipratropium bromide improve lung function in patients with chronic obstructive pulmonary disease (COPD). However, their bronchodilating effect has not yet been compared in the central and distal airways. Functional imaging using computational fluid dynamics offers the possibility of making such a comparison. The objective of this study was to assess the effects of salbutamol and ipratropium bromide on the geometry and computational fluid dynamics-based resistance of the central and distal airways.

METHODS

Five patients with Global Initiative for Chronic Obstructive Lung Disease Stage III COPD were randomized to a single dose of salbutamol or ipratropium bromide in a crossover manner with a 1-week interval between treatments. Patients underwent lung function testing and a multislice computed tomography scan of the thorax that was used for functional imaging. Two hours after dosing, the patients again underwent lung function tests and repeat computed tomography.

RESULTS

Lung function parameters, including forced expiratory volume in 1 second, vital capacity, overall airway resistance, and specific airway resistance, changed significantly after administration of each product. On functional imaging, the bronchodilating effect was greater in the distal airways, with a corresponding drop in airway resistance, compared with the central airways. Salbutamol and ipratropium bromide were equally effective at first glance when looking at lung function tests, but when viewed in more detail with functional imaging, hyporesponsiveness could be shown for salbutamol in one patient. Salbutamol was more effective in the other patients.

CONCLUSION

This pilot study gives an innovative insight into the modes of action of salbutamol and ipratropium bromide in patients with COPD, using the new techniques of functional imaging and computational fluid dynamics.

Bronchodilator responsiveness and onset of effect with budesonide/formoterol pMDI in COPD

BACKGROUND

Chronic obstructive pulmonary disease (COPD) patients are thought to have limited bronchodilator response, determined by changes in forced expiratory volume in 1s (FEV(1)). In this study, we assessed bronchodilator response in patients with COPD using not only FEV(1) but also changes in lung volume expressed as forced vital capacity (FVC) and inspiratory capacity (IC). We also evaluated the speed of onset of bronchodilation.

METHODS

Data were from 2 randomized, double-blind, placebo-controlled studies (6-months [NCT00206154]; 12-months [NCT00206167]) in patients with moderate to very severe COPD.

TREATMENTS

twice daily budesonide/formoterol pressurized metered-dose inhaler (pMDI) 320/9μg, budesonide/formoterol pMDI 160/9μg, formoterol dry powder inhaler (DPI) 9μg, placebo.

RESULTS

The percentage of patients with FEV(1) improvement (≥12% and ≥200mL; American Thoracic Society [ATS] criterion) was 34-39% post-albuterol (screening). On day of randomization (DOR), a larger proportion receiving formoterol-containing treatment exhibited reversibility within 60min: FEV(1) (57-59%). Similar results were seen for IC (50-61%) and FVC (57-67%) using the same improvement criteria. The time to ≥15% FEV(1) improvement on DOR was 5.0, 4.8, and 7.3min for budesonide/formoterol 320/9, budesonide/formoterol 160/9, and formoterol, respectively. Time to ≥15% FEV(1) improvement was better maintained with budesonide/formoterol than formoterol at treatment end (6 and 12 months).

CONCLUSIONS

Most patients with moderate to very severe COPD exhibit ATS-defined bronchodilator reversibility based on flow and lung volume measures after budesonide/formoterol pMDI or formoterol treatment. Budesonide/formoterol pMDI also has a rapid (within 5min) onset of bronchodilation that is maintained over time compared with formoterol alone.

[Evaluation of the deficiency and the submaximal exercise capacity in obstructive sleep apnoea patients]

BACKGROUND

In addition to excessive daytime somnolence, exercise limitation is a likely consequence of the cardiorespiratory problems that occur in patients who have obstructive sleep apnoea (OSA). However, few studies have evaluated the aerobic capacity of this patient group.

AIMS

To evaluate submaximal exercise capacity over the 6-minute walking test (6-MWT). To determine the factors that influence 6-minutes walking distance (6-MWD).

METHODS

INCLUSION CRITERIA

120 consecutive patients with severe OSA treated by continuous positive airway pressure who were medically stable will be included.

EXCLUSION CRITERIA

6-MWT contraindications, orthopaedic or rheumatologic diseases likely to influence walking capacity and corticosteroid therapy.

INVESTIGATIONS

polysomnography, electrocardiogram, plethysmography, and two 6-MWT's. Indicators of impaired exercise capacity: stops during the walk, 6-MWD less than or equal to predicted lower limit of normal, end walking dyspnoea greater than or equal to 5/10, oxygen saturation fall greater than or equal to five points, end walking heart rate less than or equal to 60 % maximal predicted. Data from our obese patients aged 40-60 years old will be compared with data from 45 age-matched obese subjects free from OSA.

EXPECTED RESULTS

OSA will significantly affect the submaximal exercise capacity and will accelerate the ageing of the cardiorespiratory-muscle chain. Submaximal exercise capacity of obese subjects having OSA, compared to subjects free from OSA, will be significantly deteriorated. 6-MWD of OSA patients will be significantly influenced by: resting plethysmographic data, apnoea hypopnoea index, arterial hypertension, obesity or smoking histories.