Ml In FEV1 Research Articles

The relationship between cardiometabolic index and pulmonary function among U.S. adults: insights from the National Health and Nutrition Examination Survey (2007–2012)

BackgroundPrevious findings have revealed that disorders of lipid metabolism may be a risk factor for pulmonary function damage; however, the combined effect of dyslipidemia and central obesity on pulmonary function is unclear. The cardiometabolic index (CMI) is a composite of serum lipids (triglyceride (TG)/high-density lipoprotein cholesterol (HDL-C)) and visceral fat parameters (waist-to-height ratio (WHtR)). This research aimed to investigate the link between CMI and pulmonary function, employing large-scale demographic data sourced from the National Health and Nutrition Examination Survey (NHANES) database.MethodsThis cross-sectional study used data involving 4125 adults aged 20 and above collected by NHANES between 2007 and 2012. We defined CMI as the exposure variable and measured outcomes using forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC to evaluate pulmonary function. Weighted multiple linear regression models and subgroup analyses were employed to investigate separate relationships between CMI and pulmonary function. In addition, to investigate variations across different strata and evaluate the robustness of the findings, interaction tests and sensitivity analyses were conducted.ResultsResults from the weighted multiple linear regression analysis indicated a unit increase in log2-CMI was associated with a reduction of 82.63 mL in FEV1 and 112.92 mL in FVC. The negative association remained significant after transforming log2-CMI by quartile (Q). When the log2-CMI level reached Q4, β coefficients (β) were -128.49 (95% CI: -205.85, -51.13), -169.01 (95% CI: -266.72, -71.30), respectively. According to the interaction test findings, the negative association linking log2-CMI with FEV1 and FVC persists regardless of confounding factors including age, gender, BMI, physical activity (PA), and smoking status. A subsequent sensitivity analysis provided additional confirmation of the stability and reliability of the results. For females, the inflection points for the nonlinear relationships between log2-CMI and FEV1, as well as log2-CMI and FVC, were identified at 2.33 and 2.11, respectively. While in males, a consistent negative association was observed.ConclusionsOur findings suggest that higher CMI is associated with lower FEV1 and FVC. CMI may serve as a complementary consideration to the assessment and management of pulmonary function in clinical practice.

Efficacy and safety of simultaneous combined Zephyr and Spiration valve therapy in patients with advanced pulmonary emphysema

BackgroundEndoscopic lung volume reduction with valves is a minimally invasive treatment strategy for patients with severe pulmonary emphysema. Two valve systems are currently available: Zephyr and Spiration valves. As these can be implanted simultaneously in the same procedure, the question arose as to the effect on lung function, exercise capacity and subjective disease perception after combined valve treatment. MethodsWe conducted a retrospective analysis of 108 patients with combined, simultaneous treatment of Zephyr and Spiration valves. The decision on which and how many valves to implant was based on the individual patient anatomy. Effects on lung function, exercise capacity and atelectasis formation as well as complications were evaluated 90- and 180-days post-treatment (90d-FU and 180d-FU). ResultsAt 90d-FU (n = 90), the mean change was 86.7 ± 183.7 mL for FEV1 and -645.3 ± 1276.5 mL for RV, with responder rates of 39.8 % and 46.5 %, respectively. Complete atelectasis occurred in 16.7 % and partial atelectasis in 25.5 % of patients. Six-minute walking distance increased by 27.00 m [-1.50 – 68.50m]. The rates of pneumothorax (10.2 %) 6 months after treatment were not higher than in randomized controlled trials (RCTs). Likely due to the inclusion of high-risk patients, there was a higher incidence of severe COPD exacerbation (21.3 %) and pneumonia (12.0 %) compared to RCTs. ConclusionsThe combined implantation of Zephyr and Spiration valves resulted in significant clinical and functional improvements with an acceptable risk profile. Therefore, the ability to combine both valve types in severe emphysema could be a promising option in endoscopic lung volume reduction.

Association of World Trade Center (WTC) Occupational Exposure Intensity with Chronic Obstructive Pulmonary Disease (COPD) and Asthma COPD Overlap (ACO).

Reported associations between World Trade Center (WTC) occupational exposure and chronic obstructive pulmonary disease (COPD) or asthma COPD overlap (ACO) have been inconsistent. Using spirometric case definitions, we examined that association in the largest WTC occupational surveillance cohort. We examined the relation between early arrival at the 2001 WTC disaster site (when dust and fumes exposures were most intense) and COPD and ACO in workers with at least one good quality spirometry with bronchodilator response testing between 2002 and 2019, and no physician-diagnosed COPD before 9/11/2001. COPD was defined spirometrically as fixed airflow obstruction and ACO as airflow obstruction plus an increase of ≥ 400ml in FEV1 after bronchodilator administration. We used a nested 1:4 case-control design matching on age, sex and height using incidence density sampling. Of the 17,928 study participants, most were male (85.3%) and overweight or obese (84.9%). Further, 504 (2.8%) and 244 (1.4%) study participants met the COPD and ACO spirometric case definitions, respectively. In multivariable analyses adjusted for smoking, occupation, cohort entry period, high peripheral blood eosinophil count and other covariates, early arrival at the WTC site was associated with both COPD (adjusted odds ratio [ORadj] = 1.34, 95% confidence interval [CI] 1.01-1.78) and ACO (ORadj = 1.55, 95%CI 1.04-2.32). In this cohort of WTC workers, WTC exposure intensity was associated with spirometrically defined COPD and ACO. Our findings suggest that early arrival to the WTC site is a risk factor for the development of COPD or of fixed airway obstruction in workers with pre-existing asthma.

Impact of bronchoscopic lung volume reduction with endobronchial valves on dynamic hyperinflation: Results from the PIERCE study.

Dynamic hyperinflation (DH) is a major marker of exertional dyspnoea in severe emphysema. We hypothesized that bronchoscopic lung volume reduction (BLVR) using endobronchial valves (EBVs) decreases DH. In this prospective bi-centre study from both Toulouse and Limoges Hospitals, we assessed DH during an incremental cycle ergometry before and 3months after EBVs treatment. The primary objective was to observe the change in inspiratory capacity (IC) at isotime. Target lobe volume reduction (TLVR) and changes in residual volume (RV), forced expiratory volume in one-second (FEV1 ), mMRC, 6minutes walking distance (6MWD), BODE and other dynamic measures like tele-expiratory volume (EELV) were also analysed. Thirty-nine patients were included, of whom thirty-eight presented DH. IC and EELV at isotime significantly improved (+214 mL, p= 0.004; -713 mL, p˂0.001, respectively). Mean changes were +177 mL for FEV1 (+19%, p< 0.001), -600 mL for RV (p< 0.0001), +33 m for 6MWD (p< 0.0001), respectively. Patients who responded on RV (>430 mL decrease) and FEV1 (>12% gain) had better improvements compared to non-responders (+368 mL vs. +2mL; +398 mL vs. -40 mL IC isotime, respectively). On the opposite, in patients who responded on DH (>200 mL IC isotime increase), changes in TLV (-1216 mL vs. -576 mL), FEV1 (+261 mL vs. +101 mL), FVC (+496 mL vs. +128 mL) and RV (-805 mL vs. -418 mL) were greater compared to non-responders. DH decreases after EBVs treatment, and this improvement is correlated with static changes.

Non-optimum ambient temperature may decrease pulmonary function: A longitudinal study with intensively repeated measurements among asthmatic adult patients in 25 Chinese cities.

Non-optimum ambient temperature has not been widely perceived as an important environmental risk factor for asthma, and the association between ambient temperature and pulmonary function is rarely explored. Our study aimed to investigate the associations between non-optimum ambient temperature and pulmonary function among asthmatic adult patients. We performed a longitudinal study among 4,992 eligible adult asthmatic patients in 25 cities of China from 2017 to 2020. The patients were required to complete pulmonary function test every day in the morning and evening. Linear mixed-effects models and distributed lag non-linear models were used to evaluate the associations between ambient temperature and pulmonary function. We evaluated 298,396 records of pulmonary function tests. We found inversely J-shaped exposure-response relationship curves for ambient temperature and pulmonary function. The effects of extreme low temperature occurred at lag 0h and vanished at lag 72h (almost 3days). Compared with referent temperature (29.5 °C), extreme low temperature (-9.4 °C) was associated with decreases of 60.4mL in FEV1, 299.7mL/s in PEF, and 101.5mL in FVC. Extreme high temperature (34.2 °C) was associated with decreases of 26.0mL in FEV1, 35.8mL/s in PEF, and 23.4mL in FVC. Patients of male, overweight, and elder ages were vulnerable populations, and cold effects were more prominent in the south and in areas without central heating. Both extreme low and high ambient temperatures were associated with decreased pulmonary function in adult asthmatic patients. The effect could last for almost 3days and low temperature was more harmful.

Correlation of digital flow peak with spirometry in children with and without asthma

Introduction Spirometry and peak expiratory flow measurement (PEF) are combined during functional respiratory assessments. The new digital peak flow meter (DPM) evaluates the forced expiratory volume in the first second (FEV1) and PEF. Objective To compare lung function measurements using spirometry and DPM. Methods This cross-sectional analytical study assessed FEV1 and PEF in children with and without asthma. Statistical analysis was performed to assess the agreement between the measures using the intraclass correlation coefficient (ICC), Bland–Altman, and survival agreement plot. Results 125 (3–12 y) and 196 (6–18 y) children without and with asthma, respectively, were studied. In children without asthma, the ICC for FEV1 and PEF were 0.89 and 0.86, respectively, while the corresponding values were 0.87 and 0.79, respectively, in patients with asthma. The Bland–Altman method showed a difference of −0.4 to 0.5 for FEV1 in patients without asthma, with a tendency to increase as the FEV1 increased to a certain extent. In patients with asthma, the pattern was similar for FEV1, and the PEF had a greater dispersion than among those without asthma; however, a good agreement pattern was maintained. In the survival agreement plot, when accepting a tolerance of 0.150 mL for FEV1, there was an agreement of close to 55% in both groups. Likewise, when accepting a tolerance of 0.5 L/s for PEF, an agreement of close to 60% and 50% was observed in patients without and with asthma, respectively. Conclusion DPM was effective as a measure of lung function in pediatric patients with and without asthma.

Low-level exposure to polycyclic aromatic hydrocarbons is associated with reduced lung function among Swedish young adults

BackgroundExposure to polycyclic aromatic hydrocarbons (PAHs) has been linked to adverse pulmonary effects. However, the impact of low-level environmental PAH exposure on lung function in early adulthood remains uncertain. ObjectivesTo evaluate the associations between urinary PAH metabolites and lung function parameters in young adults. MethodsUrinary metabolites of pyrene, phenanthrene, and fluorene were analysed in 1000 young adults from Sweden (age 22–25 years) using LC-MS/MS. Lung function and eosinophilic airway inflammation were measured by spirometry and exhaled nitric oxide fraction (FeNO), respectively. Linear regression analysis was used to evaluate associations between PAH metabolites and the outcomes. ResultsMedian urinary concentrations of 1-OH-pyrene, ∑OH-phenanthrene, and ∑OH-fluorene were 0.066, 0.36, 0.22 μg/L, respectively. We found inverse associations of ∑OH-phenanthrene and ∑OH-fluorene with FEV1 and FVC, as well as between 1-OH-pyrene and FEV1/FVC ratio (adjusted P < 0.05; all participants). An increase of 1% in ∑OH-fluorene was associated with a decrease of 73 mL in FEV1 and 59 mL in FVC. In addition, ∑OH-phenanthrene concentrations were, in a dose-response manner, inversely associated with FEV1 (B from −109 to −48 compared with the lowest quartile of ∑OH-phenanthrene; p trend 0.004) and FVC (B from −159 to −102 compared with lowest quartile; p-trend <0.001). Similar dose-response associations were also observed between ∑OH-fluorene and FEV1 and FVC, as well as between 1-OH-pyrene and FEV1/FVC (p-trend <0.05). There was no association between PAH exposure and FeNO, nor was there an interaction with smoking, sex, or asthma. ConclusionLow-level PAH exposure was, in a dose-response manner, associated with reduced lung function in young adults. Our findings have public health implications due to i) the widespread occurrence of PAHs in the environment and ii) the clinical relevance of lung function in predicting all-cause and cardiovascular disease mortality.

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

Many patients with mild asthma are undiagnosed and untreated due to the low diagnostic sensitivity of bronchodilation test (BDT). 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. 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. 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%, ΔFEF25-75% (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. 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.

Technical validity and usability of a novel smartphone-connected spirometry device for pediatric patients with asthma and cystic fibrosis.

BackgroundDiagnosis and follow‐up of respiratory diseases traditionally rely on pulmonary function tests (PFTs), which are currently performed in hospitals and require trained personnel. Smartphone‐connected spirometers, like the Air Next spirometer, have been developed to aid in the home monitoring of patients with pulmonary disease. The aim of this study was to investigate the technical validity and usability of the Air Next spirometer in pediatric patients.MethodsDevice variability was tested with a calibrated syringe. About 90 subjects, aged 6 to 16, were included in a prospective cohort study. Fifty‐eight subjects performed conventional spirometry and subsequent Air Next spirometry. The bias and the limits of agreement between the measurements were calculated. Furthermore, subjects used the device for 28 days at home and completed a subject‐satisfaction questionnaire at the end of the study period.ResultsInterdevice variability was 2.8% and intradevice variability was 0.9%. The average difference between the Air Next and conventional spirometry was 40 mL for forced expiratory volume in 1 second (FEV1) and 3 mL for forced vital capacity (FVC). The limits of agreement were −270 mL and +352 mL for FEV1 and −403 mL and +397 mL for FVC. About 45% of FEV1 measurements and 41% of FVC measurements at home were acceptable and reproducible according to American Thoracic Society/European Respiratory Society criteria. Parents scored difficulty, usefulness, and reliability of the device 1.9, 3.5, and 3.8 out of 5, respectively.ConclusionThe Air Next device shows validity for the measurement of FEV1 and FVC in a pediatric patient population.

How stable is lung function in patients with stable chronic obstructive pulmonary disease when monitored using a telehealth system? A longitudinal and home-based study

BackgroundMany telehealth systems have been designed to identify signs of exacerbations in patients with chronic obstructive pulmonary disease (COPD), but few previous studies have reported the nature of recorded lung function data and what variations to expect in this group of individuals. The aim of the study was to evaluate the nature of individual diurnal, day-to-day and long-term variation in important prognostic markers of COPD exacerbations by employing a telehealth system developed in-house.MethodsEight women and five men with COPD performed measurements (spirometry, pulse oximetry and the COPD assessment test (CAT)) three times per week for 4–6 months using the telehealth system. Short-term and long-term individual variations were assessed using the relative density and weekly means respectively. Quality of the spirometry measurements (forced expiratory volume in one second (FEV1) and inspiratory capacity (IC)) was assessed employing the criteria of American Thoracic Society (ATS)/European Respiratory Society (ERS) guidelines.ResultsClose to 1100 measurements of both FEV1 and IC were performed during a total of 240 patient weeks. The two standard deviation ranges for intra-individual short-term variation were approximately ±210 mL and ± 350 mL for FEV1 and IC respectively. In long-term, spirometry values increased and decreased without notable changes in symptoms as reported by CAT, although it was unusual with a decrease of more than 50 mL per measurement of FEV1 between three consecutive measurement days. No exacerbation occurred. There was a moderate to strong positive correlation between FEV1 and IC, but weak or absent correlation with the other prognostic markers in the majority of the participants.ConclusionsAlthough FEV1 and IC varied within a noticeable range, no corresponding change in symptoms occurred. Therefore, this study reveals important and, to our knowledge, previously not reported information about short and long-term variability in prognostic markers in stable patients with COPD. The present data are of significance when defining criteria for detecting exacerbations using telehealth strategies.

Reduced Cross-Shift Lung Function and Respiratory Symptoms among Integrated Textile Factory Workers in Ethiopia.

Chronic respiratory symptoms and reduction in lung function has been described as a common health problem among textile workers in low- and middle-income countries. The objective of this study was to measure lung function and respiratory symptoms among workers from an integrated textile factory. A comparative cross-sectional study design with a cross-shift lung function measurement was performed in 306 cotton dust exposed workers from an integrated textile factory and 156 control workers from a water bottling factory. An integrated textile factory typically has four main production departments (spinning, weaving, finishing, and garment) that process raw cotton and manufacture clothes or fabrics. Respiratory symptoms were assessed by adopting the standard American Thoracic Society questionnaire. Descriptive statistics and logistic and linear regression analysis were used. The prevalence of respiratory symptoms was significantly higher among textile workers (54%) than in controls (28%). Chronic cough, chest tightness, and breathlessness were significantly higher among textile workers (23%, 33%, and 37%, respectively) than in the control group (5%, 17% and 6%, respectively). Breathlessness was the most prevalent chronic respiratory symptom with highest adjusted odds ratio 9.4 (95% CI 4.4–20.3). A significantly higher cross-shift lung function reduction was observed among textile workers (123 mL for FEV1 and 129 mL for FVC) compared with the control group (14 mL for FEV1 and 12 mL for FVC). Thus, workers’ respiratory health protection programs should be strengthened in textile factories.

A European Multi‐Center, Randomized, Double‐Blind Trial of Pirfenidone in Bronchiolitis‐Obliterans‐Syndrome Grade 1‐3 in Lung Transplant Recipients (European Trial of Pirfenidone in BOS (EPOS))

Bronchiolitis obliterans syndrome (BOS), the most common form of chronic lung allograft dysfunction (CLAD), and the major limitation to long-term survival after lung transplantation. BOS affects up to 50% of lung transplant recipients within 5 years after transplant, causing significant morbidity and mortality. BOS manifesting early after transplantation shows a poorer prognosis than late-onset BOS. There are only few studies assessing treatment efficacy, but only a minority of patients respond to current treatment options. From trans-bronchial surveillance biopsies and autopsies from diseased transplant recipients, the BOS lesions reveal interstitial fibrosis, which suggest the possible use of anti-fibrotic agent like Pirfenidone. We hypothesized that there is a statistically significant difference between randomized study groups in the change in FEV1 from baseline to 6 months. This trial is investigator-initiated and including nine European expert lung transplant centers. Patients with new onset progressive BOS were randomized in a 1:1 ratio to receive either Pirfenidone or the matching placebo treatment for 6 months. Progressive BOS was defined by the following: at least 3 FEV1-measurements in the last 6 months, each at least 3 weeks apart, a total decline of at least 200ml in FEV1, and a mean decline of at least 50 ml in the last two measurements, as well as the exclusion of other reasons for FEV1 decline by an expert panel. All patients had to be on at least 250mg Azithromycin 3 times a week for at least 4 weeks prior to inclusion. A total of 80 patients were planned included in the study 40 in each group. The primary endpoint is to evaluate the effect of Pirfenidone on the change in FEV1 (ml) over 6 months in lung transplant recipients with BOS, who are treated with Azithromycin. Secondary endpoints are as follows; Categorical percentage change in FEV1, Change in FVC, Change in TLC, Change in FEV1/FVC ratio, Number of patients with treatment failure, Change in BOS grade, Change in percent predicted diffusion capacity (DLco), Change in functional level as assessed by 6MWT, Hospital admission for any reason, Death or re-transplantation rates, Change in quality of life assessed by EQ5D.

The influence of species richness in primary school surroundings on children lung function and allergic disease development

Primary schools represent important environments for biodiversity exposure and thus may play a crucial role on early-life immunomodulation, protecting against allergic sensitization. The aim of this study was to understand how the exposure to different levels of species richness surrounding urban primary schools may influence the development of allergic diseases and asthma in children. A species richness index (SRI), evaluating habitat diversity in terms of amphibians, birds, reptiles, and small mammals, was estimated and attributed to 20 primary schools in the city of Porto, Portugal. The SRI was measured considering a 100m straight-line buffer around the schools. Children who attended the participating schools were invited to participate in the study, performed spirometry with bronchodilation and skin-prick tests, and had their parents fill a questionnaire concerning allergy and asthma symptoms, as well as demographic and socioeconomic data. Asthma was defined according to three distinct criteria. The study results showed significant and positive associations between the exposure to species richness in schools and the forced expiratory volume at the first second (FEV1 ) and forced vital capacity (FVC) parameters both before and after bronchodilation, independently of the asthma and atopic status. Fully adjusted models revealed that a unitary increment in the SRI was associated with an average increase of approximately 2 and 3mL in FEV1 and FVC, respectively. Species richness in school surroundings may impact lung function development in children. However, this increase in lung function was not associated with any clinically relevant protective effect on allergy and asthma development.

Healthcare Professionals' Preferred Efficacy Endpoints and Minimal Clinically Important Differences in the Assessment of New Medicines for Chronic Obstructive Pulmonary Disease.

BackgroundRegistration authorities evaluate effects of new medicines for chronic obstructive pulmonary disease (COPD) on airway obstruction, dyspnea, health status and exacerbations. To establish clinical relevance, minimal clinically important differences (MCIDs) are used. The aim of this study was to investigate which efficacy endpoints and MCIDs healthcare professionals consider clinically relevant for new COPD medicines.Materials and Methods7,731 Healthcare professionals received an electronic questionnaire. Participants were asked for: 1) preferred efficacy endpoints for new COPD medicines and 2) cut-off values defining clinical relevance for forced expiratory volume in 1 sec (FEV1), Transition Dyspnea Index (TDI) and St. George’s Respiratory Questionnaire (SGRQ). Those cut-off values were compared to the MCIDs used by registration authorities, namely 100 ml for FEV1, 1 unit for TDI and 4 units for SGRQ.Results227 Healthcare professionals responded to the questionnaire. Most preferred efficacy endpoints were exacerbations (51.0%), airway obstruction (46.9%) and health status (44.9%). Mean cut-off values for TDI and SGRQ were significantly higher than the corresponding MCIDs, mean differences 1.5 (95%CI = 1.3–1.8, p < 0.001) and 7.0 (95%CI = 5.1–8.8, p < 0.001), respectively. The mean cut-off value for FEV1 was comparable to the MCID (mean difference 2.2, 95%CI = -19.9–24.3, p = 0.84).ConclusionsHealthcare professionals largely agree with efficacy endpoints used for the evaluation of new COPD medicines. However, they seem to prefer higher cut-off values for clinical relevance for TDI and SGRQ than the registration authorities. Effects of new medicines on TDI and SGRQ that are considered clinically relevant by registration authorities do, therefore, not necessarily reflect healthcare professionals’ perspectives on clinical relevance.

Relative and absolute lung function change in a general population aged60-102 years.

Data on longitudinal lung function change in the elderly are scarce. Uncertainty remains about whether to use absolute or relative change and how it relates to subject demographics.We studied absolute and relative forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) change in a population-based geriatric sample using a repeated measurements model adjusted for age, sex, smoking habits, heart failure, hypertension, diabetes, coronary heart disease, educational level, occupation, alcohol consumption, C-reactive protein (CRP) and body mass index. 3736 participants aged 60–102 years completed between one and five spirometries during 13.5 years of follow-up. Lung volumes, FEV1 quotient (Q) and Global Lung Initiative (GLI)-2012 and National Health and Nutrition Examination Survey (NHANES) III z-scores were presented from 6932 spirometries.Adjusted absolute change per year (95% CI) was −51.7 (−63.7–−39.9) mL for FEV1 and −56.2 (−73.6–−38.8) mL for FVC. Adjusted relative change per year was −2.97 (−3.53–−2.40)% for FEV1 and −2.46 (−3.07–−1.85)% for FVC. Risk factors for increased relative FVC and FEV1 decline were female sex, higher age, current smoking habits, elevated CRP (nonsignificant for FEV1, p=0.057) and low educational level. For increased absolute decline the risk factors were male sex and being a current smoker for FEV1 and low education for FVC.Relative but not absolute change correlated significantly with clinically relevant markers of functional status and may be superior to absolute change in risk factor analysis. Cross-sectional reduction in terms of FEV1Q was ∼1 unit per 10 years for both sexes. Proportions of subjects with results below lower limit of normal using NHANES III were close to anticipated, but were two to four times higher than expected using GLI-2012.

Factors Associated with Indacaterol Response in Tuberculosis-Destroyed Lung with Airflow Limitation.

BackgroundPulmonary tuberculosis can result in anatomical sequelae, and cause airflow limitation. However, there are no treatment guidelines for patients with a tuberculosis-destroyed lung. Recently, indacaterol effectiveness in chronic obstructive pulmonary disease (COPD) patients with Tuberculosis history (INFINITY) study revealed indacaterol provided bronchodilation and symptom improvement in COPD patients with a tuberculosis-destroyed lung.MethodsWe conducted a post-hoc subgroup analysis of the randomized controlled trial, the INFINITY study, to determine factors associated with indacaterol response in a tuberculosis-destroyed lung with airflow limitation. Data from 68 patients treated with inhaled indacaterol, were extracted and analyzed. Factors associated with the response of forced expiratory volume in one second (FEV1) to indacaterol treatment, were determined using linear regression analysis.ResultsOf 62 patients included, 68% were male, and 52% had history of cigarette smoking. Patients revealed mean FEV1 of 50.5% of predicted value with mean improvement of 81.3 mL in FEV1 after indacaterol treatment for 8 weeks. Linear regression analysis revealed factors associated with response of FEV1 to indacaterol included a short duration of smoking history, and high short-acting bronchodilator response. When patients with history of smoking were excluded, factors associated with response of FEV1 to indacaterol included high short-acting bronchodilator response, and poor healthrelated quality of life score as measured by St. George's Respiratory Questionnaire for COPD.ConclusionIn a tuberculosis-destroyed lung with airflow limitation, short-acting bronchodilator response and smoking history can play a critical role in predicting outcomes of indacaterol treatment.

Asthma Exacerbations Associated with Lung Function Decline in Patients with Severe Eosinophilic Asthma

Limited data describe the association between the frequency of asthma exacerbations and the decline in lung function in severe asthma. To determine whether asthma exacerbations are associated with enhanced decline in lung function. Changes in lung function were analyzed retrospectively using data from the DREAM and MENSA studies of mepolizumab intervention in patients with severe asthma. Patients were either nonsmokers or former smokers. A linear regression model was used to analyze the relationship between the number of exacerbations and decline in FEV1 across treatment groups. In a combined post hoc analysis, 57% (n= 572) of patients had no exacerbations and experienced an improvement in postbronchodilator FEV1 of 143 mL. In contrast, in patients who experienced 3 or more exacerbations, there was a decrease in postbronchodilator FEV1 of 77 mL in the combined analysis. The linear modeling analysis estimated that for each exacerbation seen during the observational period, there was a decrease of 50 mL in FEV1 (P < .001). A direct relationship between the number of exacerbations in patients with severe eosinophilic asthma and decline in lung function was observed. Repeated exacerbations may be associated with accelerated loss of lung function.

A clinical study of pulmonary function tests in patients with COPD exacerbation

Background: COPD is now recognized as an important cause of morbidity and mortality world over. This study aims to assess the serial change in spirometric values and 6-minute walking distance in COPD patients following exacerbation.Methods: A prospective study of 40 patients who were admitted to St. Johns Medical College Hospital with Acute Exacerbation of COPD. After proper history, initial assessment and evaluation, appropriate treatment started according to standard hospital protocols. Spirometry and 6-minute walk distance (6MWD) was done at discharge and at an interval of two and six months during follow up. All the collected data was tabulated and statistically analysed by using software’s SAS 9.2, SPSS 15.0.Results: Among the 40 patients studied, there was a 9.18% drop in FVC (from 2.83 litres to 2.57 litres), 13.26% change in the FEV1/FVC ratio with a mean drop of 150 ml in FEV1 (1.5 litres to 1.35 litres) and 25 meters decline of 6MWD from 391.45 to 366.63 over 6 months follow up period, although none of them were statistically significant.Conclusions: A drop in FEV1 and (6MWD) minute walk distance was found in our study population over 6 months follow period after COPD exacerbations which is in line with the various study reports available in the literature reinforcing the fact that patients with increased airway inflammation show faster decline in FEV1.

Longitudinal decline in lung function among older construction workers

BackgroundOccupational exposures to vapours, gasses, dusts and fumes (VGDF) and chest X-ray abnormalities by the International Labour Office (ILO) classification system are associated with reduced lung function, with the majority...

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?

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. 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. 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. 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.