The Impact of FEV1/FVC Ratio on the Clinical Outcomes in Acute Coronary Syndrome Patients Treated with Dual Anti-Platelet Agents.

Background: Few studies have investigated the clinical efficacy and pulmonary side effects of different P2Y12 inhibitors in acute coronary syndrome (ACS) patients. The aim of this study was to explore the impact of forced expiratory volume in 1 second over forced vital capacity (FEV1/FVC) ratio on the clinical outcomes in ACS patients treated with dual antiplatelet therapy after percutaneous coronary intervention (PCI). Methods: ACS patients who underwent PCI, had documented pre-existing spirometry tests, and received aspirin with either ticagrelor or clopidogrel were enrolled for retrospective analysis. Results: Of the enrolled ACS patients, 275 and 247 received ticagrelor and clopidogrel, respectively. The incidence of wheeze was significantly higher in the ticagrelor group compared to the clopidogrel group within 360 days (14.91% vs. 8.09%, p = 0.016). Multivariable analysis revealed that ticagrelor treatment, as compared to clopidogrel treatment, independently predicted 1-year hospitalization for acute exacerbation (AE) of obstructive airway disease (hazard ratio: 3.44; 95% confidence interval: 1.92 to 6.15; p < 0.01). The receiver operating characteristic curve indicated that an FEV1/FVC ratio of 63.85% had the highest sensitivity and specificity for predicting the incidence of AE of obstructive airway disease within 1 year (p < 0.001). The 1-year hospitalization rate for AE of obstructive airway disease was significantly higher in the ticagrelor group when the FEV1/FVC ratio was < 63%. Conclusions: This study demonstrated higher incidence of wheeze and hospitalization for AE of obstructive airway disease in ACS patients treated with ticagrelor compared to clopidogrel. Furthermore, the FEV1/FVC ratio ≤ 63% in the ACS patients predicted hospitalization for AE of obstructive airway disease in 1 year.

Lung Development Genes and Adult Lung Function.

Rationale: Poor lung health in adult life may occur partly through suboptimal growth and development, as suggested by epidemiological evidence pointing to early life risk factors.Objectives: To systematically investigate the effects of lung development genes on adult lung function.Methods: Using UK Biobank data, we tested the association of 391 genes known to influence lung development with FVC and FEV1/FVC. We split the dataset into two random subsets of 207,616 and 138,411 individuals, using the larger subset to select the most promising signals and the smaller subset for replication.Measurements and Main Results: We identified 55 genes, of which 36 (16 for FVC, 19 for FEV1/FVC, and one for both) had not been identified in the largest, most recent genome-wide study of lung function. Most of these 36 signals were intronic variants; expression data from blood and lung tissue showed that the majority affect the expression of the genes they lie within. Further testing of 34 of these 36 signals in the CHARGE and SpiroMeta consortia showed that 16 replicated after Bonferroni correction and another 12 replicated at nominal significance level. Of the 55 genes, 53 fell into four biological categories whose function is to regulate organ size and cell integrity (growth factors; transcriptional regulators; cell-to-cell adhesion; extracellular matrix), suggesting that these specific processes are important for adult lung health.Conclusions: Our study demonstrates the importance of lung development genes in regulating adult lung function and influencing both restrictive and obstructive patterns. Further investigation of these developmental pathways could lead to druggable targets.

The associations between dietary pattern of chronic obstructive pulmonary disease patients and depression: a cross-sectional study.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a common lung disease during middle age which one of its complications is depression. Depression is considered one of the major causes of severe disability worldwide. One of the factors that affect the severity and incidence of this disease is a lifestyle, especially dietary pattern. On the other hand, some studies showed the relationship between dietary patterns and depression. The present study aims to investigate the dietary patterns of people with chronic obstructive pulmonary disease and its association with depression. METHODS: The present cross-sectional study was performed on 220 patients (mean ± SD age = 54.58 ± 5.08) with chronic obstructive pulmonary disease (56.6% men, 43.4% women) from Tabriz, Iran. Questionnaires of general information, food frequency, Beck depression and physical activity were completed. The dominant dietary patterns were determined by factor analysis, and their relationship with depression was discussed by regression analysis. RESULTS: Three dominant dietary patterns were identified as healthy, unhealthy, and mixed dietary patterns. An inverse relationship was found between healthy and mixed dietary patterns with depression. There is no meaningful connection between unhealthy dietary patterns and depression. Depression had a significant inverse relationship with physical activity. There was no relationship between dietary patterns and Forced Expiratory Volume for 1 s (FEV1) and Forced Vital Capacity (FVC) criteria. A positive and significant relationship was observed between mixed dietary patterns with FEV1/FVC. CONCLUSION: Inverse relationships exist between healthy dietary patterns and depression in patients with COPD, and improves the function of the lungs. Further studies are needed to show the exact relationship between diet and COPD depression.

Spirometric reference values in heathy Chinese adults in Taiwan: The secular changes and comparison with other Asian populations.

BACKGROUND/PURPOSE: Although the lung function test has played an important role in respiratory care for a long time, valid spirometry reference values in the Chinese population in Taiwan remain to be elucidated. METHODS: 2963 healthy Taiwanese subjects aged 21 to 88 years (1765 males, 59.6%) from February 2015 to February 2017 were enrolled. The subjects attempted to meet the 2005 American Thoracic Society (ATS) and the European Respiratory Society (ERS) guidelines when performing forced expiratory spirograms. We would like to establish the spirometry predictive equations for forced expiratory volume (FEV1), forced vital capacity (FVC), FEV1/FVC, and lower limit of normal (LLN) in Taiwan and compare with other Asian populations. RESULTS: We established the spirometry predictive equations using a linear model for the entire population, using age and height as independent variables, which best predicted all spirometry parameters for sea level and highland subjects. We found that the values of FEV1 and FVC for the Taiwanese subjects in our study were systematically lower than those reported in South Korea, Japan, and China, but higher than the values in Yang's 1993 and Pan's 1997 Taiwan study. CONCLUSION: This study addressed the up-to-date spirometry reference equations and values for a healthy adult Chinese population in Taiwan.

DNA methylation is associated with lung function in never smokers.

BACKGROUND: Active smoking is the main risk factor for COPD. Here, epigenetic mechanisms may play a role, since cigarette smoking is associated with differential DNA methylation in whole blood. So far, it is unclear whether epigenetics also play a role in subjects with COPD who never smoked. Therefore, we aimed to identify differential DNA methylation associated with lung function in never smokers. METHODS: We determined epigenome-wide DNA methylation levels of 396,243 CpG-sites (Illumina 450 K) in blood of never smokers in four independent cohorts, LifeLines COPD&C (N = 903), LifeLines DEEP (N = 166), Rotterdam Study (RS)-III (N = 150) and RS-BIOS (N = 206). We meta-analyzed the cohort-specific methylation results to identify differentially methylated CpG-sites with FEV1/FVC. Expression Quantitative Trait Methylation (eQTM) analysis was performed in the Biobank-based Integrative Omics Studies (BIOS). RESULTS: A total of 36 CpG-sites were associated with FEV1/FVC in never smokers at p-value< 0.0001, but the meta-analysis did not reveal any epigenome-wide significant CpG-sites. Of interest, 35 of these 36 CpG-sites have not been associated with lung function before in studies including subjects irrespective of smoking history. Among the top hits were cg10012512, cg02885771, annotated to the gene LTV1 Ribosome Biogenesis factor (LTV1), and cg25105536, annotated to Kelch Like Family Member 32 (KLHL32). Moreover, a total of 11 eQTMS were identified. CONCLUSIONS: With the identification of 35 CpG-sites that are unique for never smokers, our study shows that DNA methylation is also associated with FEV1/FVC in subjects that never smoked and therefore not merely related to smoking.

Effect of doxycyline in chronic obstructive pulmonary disease - An exploratory study.

PURPOSE: Various mechanisms, including oxidative stress, inflammation, and protease-antiprotease imbalance are proposed for the progressive decline in lung function in chronic obstructive pulmonary disease (COPD). Doxycycline, a broad spectrum tetracycline antibiotic, is reported to have non-antimicrobial matrix metalloproteinases (MMP) inhibitory action in various inflammatory conditions. The effect of doxycycline in COPD is hereby assessed in the present randomized prospective study. PATIENTS AND METHODS: The first group of COPD patients (n = 30; mild (n = 3), moderate (n = 6), severe (n = 7), very severe (n = 14) as per GOLD II & III criteria was prescribed the standard therapy, a combination of (i) short acting anti-muscarinic agent (SAMA) + short acting ß2 agonist (SABA) inhaled and (ii) corticosteroid inhaled (ICS) + long acting ß2 agonist (LABA) (iii) ICS + LABA + LAMA. Whereas doxycycline (100 mg), was used daily once or twice as per Body Mass Index (BMI), as an add-on to existing standard therapy for the second group of patients (n = 30; mild (n = 2), moderate (n = 7), severe (n = 8), very severe (n = 13). All recruited patients were followed-up after 3 months of treatment. Lung function index FEV1(%) predicted, FEV1/FVC (%), quality of life status including COPD Assessment Test (CAT), St. George's Respiratory Questionnaire (SGRQ) were assessed. Routine blood cell count also was performed. RESULTS: Biochemical analysis included estimation of oxidative stress markers, inflammatory cytokines and proteases in plasma of both the groups. Reduction in oxidative stress is evidenced by a significant decrease in Lipid hydro peroxides (LPO), total oxidative stress (TOS) and increase in glutathione peroxidase (GSH-PX), reduced glutathione (GSH) and total anti-oxidant capacity (TAO) nitrite and nitrate (NOx) along with peroxynitrate following 3 months of add-on doxycycline treatment. Reduced levels of cytokines such as interleukin IL-6, TNF-α, IL-8 were also observed. Multivariate analysis identified TNF-α major effective discriminant among pre and post doxycycline treated COPD patients. The expression of TNF-α was inversely correlated with FEV1/FVC (%) changes. The levels of MMP-2 and MMP-9/tissue inhibitors of metalloproteinases (TIMP)-1 ratio (MMP-9/ TIMP-1), also decreased significantly and the decline could be associated with TOS. A significant increase in bilirubin and reduced glutathione (GSH) level was noticed in standard therapy group. CONCLUSION: These data suggest that the improvement in lung function and quality of life in COPD patients may probably be attributed to the antioxidant, anti-inflammatory and anti-MMP activity of doxycycline. The potential therapeutic role of long-term doxycycline, in addition to its traditional antibiotic effect, definitely warrants further attention.

Spirometric instability - another hurdle in achieving real-world COPD diagnostic criteria?

Globally, mortality, morbidity and the economic burden of chronic obstructive pulmonary disease (COPD) are on the rise. In addition, its diagnosis continues to pose challenges to the physicians, which is compounded further by its new feature "spirometric instability." Based on the findings from the two recent observational studies, the Global Initiative for Chronic Obstructive Lung Disease (GOLD) recommended repeat spirometry for the individuals with a fixed ratio between 0.6 and 0.8. In this perspective, we discuss the uncertainties and consequences of this critical update in the 2018 GOLD report.

Relationship between advanced glycation end-product accumulation in the skin and pulmonary function.

. [Purpose] This study aimed to evaluate the relationship between advanced glycation end-product accumulation and pulmonary function in a general population with normal spirometry results. [Subjects and Methods] A total of 201 subjects (mean age, 56 ± 11 years; males, 58%) enrolled in this study. Subjects were classified into two groups (younger group [<65 years old] and elderly group [≥65 years old]). Skin autofluorescence was assessed as an estimate of advanced glycation end-product. Forced vital capacity and forced expiratory volume in one second were measured using a spirometer, and the forced expiratory volume in one second/forced vital capacity ratio (FEV1/FVC) was calculated. [Results] Skin autofluorescence was not an independent factor associated with FEV1/FVC in the younger group, but both skin autofluorescence and pack-years of smoking were significant independent factors associated with FEV1/FVC in the elderly group. [Conclusion] Advanced glycation end-product accumulation, assessed by skin autofluorescence, is an independent factor negatively associated with FEV1/FVC in elderly people with normal spirometry results.

Metabolomic profiling of lung function in Costa-Rican children with asthma.

BACKGROUND: The development of novel therapeutics and treatment regimens for the management of asthma is hindered by an incomplete understanding of its heterogeneous nature and pathophysiology. Metabolomics can provide an integrated and global profile of a biological system in a dysregulated state, making it a valuable tool to identify biomarkers along the disease development pathway and to understand the biological mechanisms driving that pathway. METHODS: Liquid chromatography-mass spectrometry metabolomic profiling was conducted on plasma samples provided at recruitment for 380 children with asthma from the 'Genetic Epidemiology of Asthma in Costa Rica Cohort'. Metabolites associated with three clinical characteristics of asthma severity (i) airway hyper-responsiveness (AHR) (ii) percent-predicted forced expiratory volume in one second/forced vital capacity ratio (FEV1/FVC), and (iii) FEV1/FVC post-bronchodilator were identified and their discriminatory ability assessed. Metabolite set enrichment analyses was applied to explore the biology underlying these relationships. RESULTS: AHR was associated (p<0.05) with 91 of 574 metabolites (15.9%), FEV1/FVC pre-bronchodilator with 102(17.8%), and FEV1/FVC post-bronchodilator with 155 (27.0%). The findings suggest that these characteristics capture some common and some distinct phenotypic aspects of lung function; glycerophospholipid, linoleic acid and pyrimidine metabolism were common to all three characteristics. The corresponding metabolomic profiles showed moderate but robust discriminatory ability. CONCLUSIONS: The results confirm the existence of an asthma severity metabolome. However, differences in the metabolomic profiles of the three lung function characteristics studied, suggest that refinement of both phenotype classification and metabolite selection should be a priority as the field of asthma metabolomics progresses.

Age at menarche and lung function: a Mendelian randomization study.

A trend towards earlier menarche in women has been associated with childhood factors (e.g. obesity) and hypothesised environmental exposures (e.g. endocrine disruptors present in household products). Observational evidence has shown detrimental effects of early menarche on various health outcomes including adult lung function, but these might represent spurious associations due to confounding. To address this we used Mendelian randomization where genetic variants are used as proxies for age at menarche, since genetic associations are not affected by classical confounding. We estimated the effects of age at menarche on forced vital capacity (FVC), a proxy for restrictive lung impairment, and ratio of forced expiratory volume in one second to FVC (FEV1/FVC), a measure of airway obstruction, in both adulthood and adolescence. We derived SNP-age at menarche association estimates for 122 variants from a published genome-wide meta-analysis (N = 182,416), with SNP-lung function estimates obtained by meta-analysing three studies of adult women (N = 46,944) and two of adolescent girls (N = 3025). We investigated the impact of departures from the assumption of no pleiotropy through sensitivity analyses. In adult women, in line with previous evidence, we found an effect on restrictive lung impairment with a 24.8 mL increase in FVC per year increase in age at menarche (95% CI 1.8-47.9; p = 0.035); evidence was stronger after excluding potential pleiotropic variants (43.6 mL; 17.2-69.9; p = 0.001). In adolescent girls we found an opposite effect (-56.5 mL; -108.3 to -4.7; p = 0.033), suggesting that the detrimental effect in adulthood may be preceded by a short-term post-pubertal benefit. Our secondary analyses showing results in the same direction in men and boys, in whom age at menarche SNPs have also shown association with sexual development, suggest a role for pubertal timing in general rather than menarche specifically. We found no effect on airway obstruction (FEV1/FVC).

Relationship between pulmonary function and elevated glycated hemoglobin levels in health checkups: A cross-sectional observational study in Japanese participants.

BACKGROUND: Insulin resistance has been associated with cytokines, including interleukin-6 and tumor necrosis factor alpha soluble receptor, both of which are elevated in chronic obstructive pulmonary disease (COPD). Few studies have investigated the relationship between pulmonary function tests using spirometry (PFT) and fasting plasma glucose (FPG) or glycated hemoglobin (HbA1c) levels in Japanese participants. The purpose of this study was to clarify the relationship between PFT in Japanese people who had health checkups and their FPG or HbA1c levels. In the context of preventative medicine, we intend to connect early detection of COPD to an index of blood sugar. METHODS: From August 2013 through March 2014, 1019 participants underwent health checkups. PFT, FPG, and HbA1c measurements were conducted. HbA1c levels were measured according to National Glycohemoglobin Standardization Program guidelines. RESULTS: Participants with FPG ≥100 mg/dL and HbA1c ≥5.6% showed a significantly lower forced expiratory volume in 1 s:forced vital capacity ratio (FEV1/FVC) compared to participants with lower FPG and Hb1Ac levels. Prevalence of FEV1/FVC values <70% in PFT differed significantly depending on sex, age, body mass index, FPG, HbA1c, and smoking habits. Age (≥60 years), HbA1c (≥5.6%), and current or former smoking were associated with FEV1/FVC values <70%. CONCLUSION: In Japan, HbA1c levels were higher in participants with FEV1/FVC values <70% in PFT than in those with FEV1/FVC ≥70%. In preventive medicine, PFT by spirometry should be performed in elderly participants with elevated HbA1c levels who are current or former smokers.

Subclinical respiratory dysfunction in chronic cervical cord compression: a pulmonary function test correlation.

OBJECTIVE Respiratory abnormalities are well documented in acute spinal cord injury; however, the literature available for respiratory dysfunction in chronic compressive myelopathy (CCM) is limited. Respiratory dysfunction in CCM is often subtle and subclinical. The authors studied the pattern of respiratory dysfunction in patients with chronic cord compression by using spirometry, and the clinical and surgical implications of this dysfunction. In this study they also attempted to address the postoperative respiratory function in these patients. METHODS A prospective study was done in 30 patients in whom cervical CCM due to either cervical spondylosis or ossification of the posterior longitudinal ligament (OPLL) was diagnosed. Thirty age-matched healthy volunteers were recruited as controls. None of the patients included in the study had any symptoms or signs of respiratory dysfunction. After clinical and radiological diagnosis, all patients underwent pulmonary function tests (PFTs) performed using a standardized Spirometry Kit Micro before and after surgery. The data were analyzed using Statistical Software SPSS version 13.0. Comparison between the 2 groups was done using the Student t-test. The Pearson correlation coefficient was used for PFT results and Nurick classification scores. A p value < 0.05 was considered significant. RESULTS Cervical spondylotic myelopathy (prolapsed intervertebral disc) was the predominant cause of compression (n = 21, 70%) followed by OPLL (n = 9, 30%). The average patient age was 45.06 years. Degenerative cervical spine disease has a relatively younger onset in the Indian population. The majority of the patients (n = 28, 93.3%) had compression at or above the C-5 level. Ten patients (33.3%) underwent an anterior approach and discectomy, 11 patients (36.7%) underwent decompressive laminectomy, and the remaining 9 underwent either corpectomy with fusion or laminoplasty. The mean preoperative forced vital capacity (FVC) (65%) of the patients was significantly lower than that of the controls (88%) (p < 0.001). The mean postoperative FVC (73.7%) in the patients showed significant improvement compared with the preoperative values (p = 0.003). The mean postoperative FVC was still significantly lower than the control value (p = 0.002). The mean preoperative forced expiratory volume in 1 second (FEV1) (72%) of the patients was significantly lower than that of the controls (96%) (p < 0.001). The mean postoperative FEV1 (75.3%) in the cases showed no significant improvement compared with the preoperative values (p = 0.212). The mean postoperative FEV1 was still significantly lower than the control value (p < 0.001). The mean postoperative FEV1/FVC was not significantly different from the control value (p = 0.204). The mean postoperative peak expiratory flow rate was significantly lower than the control value (p = 0.01). The mean postoperative maximal voluntary ventilation was still significantly lower than the control value (p < 0.001). On correlating the FVC and Nurick scores using the Pearson correlation coefficient, a negative correlation was found. CONCLUSIONS There is subclinical respiratory dysfunction and significant impairment of various lung capacities in patients with CCM. The FVC showed significant improvement postoperatively. Respiratory function needs to be evaluated and monitored to avoid potential respiratory complications.

Mucosal-Associated Invariant T Cell Deficiency in Chronic Obstructive Pulmonary Disease.

Mucosal-associated invariant T (MAIT) cells have been reported to play an important role in mucosal immunity. However, little is known about the roles of MAIT cells in chronic obstructive pulmonary disease (COPD). The aims of this study were to examine the levels of circulating MAIT cells and their subsets in COPD patients and to investigate the potential relationship between clinical parameters and MAIT cell levels. Forty-five COPD patients and 57 healthy control subjects were enrolled in the study. Circulating MAIT cells and their subset levels in the peripheral blood were measured by flow cytometry. Disease grades were classified according to the GOLD criteria for the assessment of severity of COPD. Circulating MAIT cell levels were found to be significantly reduced in COPD patients. In particular, this MAIT cell deficiency was more prominent in CD8+ and double-negative T cell subsets. Interestingly, elevated serum C-reactive protein level and reduced FEV1/FVC ratio were associated with MAIT cell deficiency in COPD patients. Furthermore, the circulating MAIT levels were found to be significantly lower in patients with moderate to severe COPD than in patients with mild COPD. Our data shows that MAIT cells are numerically deficient in the peripheral blood of patients with COPD. In addition, this MAIT cell deficiency was found to reflect inflammatory activity and disease severity. These findings provide important information for monitoring the changes in MAIT cell levels and for predicting the prognosis during the disease course.

High-Resolution Time-Frequency Spectrum-Based Lung Function Test from a Smartphone Microphone.

In this paper, a smartphone-based lung function test, developed to estimate lung function parameters using a high-resolution time-frequency spectrum from a smartphone built-in microphone is presented. A method of estimation of the forced expiratory volume in 1 s divided by forced vital capacity (FEV1/FVC) based on the variable frequency complex demodulation method (VFCDM) is first proposed. We evaluated our proposed method on 26 subjects, including 13 healthy subjects and 13 chronic obstructive pulmonary disease (COPD) patients, by comparing with the parameters clinically obtained from pulmonary function tests (PFTs). For the healthy subjects, we found that an absolute error (AE) and a root mean squared error (RMSE) of the FEV1/FVC ratio were 4.49% ± 3.38% and 5.54%, respectively. For the COPD patients, we found that AE and RMSE from COPD patients were 10.30% ± 10.59% and 14.48%, respectively. For both groups, we compared the results using the continuous wavelet transform (CWT) and short-time Fourier transform (STFT), and found that VFCDM was superior to CWT and STFT. Further, to estimate other parameters, including forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), and peak expiratory flow (PEF), regression analysis was conducted to establish a linear transformation. However, the parameters FVC, FEV1, and PEF had correlation factor r values of 0.323, 0.275, and -0.257, respectively, while FEV1/FVC had an r value of 0.814. The results obtained suggest that only the FEV1/FVC ratio can be accurately estimated from a smartphone built-in microphone. The other parameters, including FVC, FEV1, and PEF, were subjective and dependent on the subject's familiarization with the test and performance of forced exhalation toward the microphone.

Prognostic value of forced expiratory volume in 1 second/forced vital capacity in idiopathic pulmonary fibrosis.

Emphysema on high-resolution computed tomography of the chest is the recent focus in the general practice in idiopathic pulmonary fibrosis (IPF). However, adequate attention has not been paid to obstructive disorder. Therefore, we retrospectively evaluated the association between the degree of airway obstruction and longevity in IPF subjects, with a hypothesis that lower forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) has an impact on prognosis. One hundred and fourteen consecutive IPF subjects who had been diagnosed with IPF and had undergone evaluation including pulmonary function test from January 2008 to May 2013 were included in the study. The relationship between baseline data and survival was examined. FEV1/FVC was widely distributed, ranging from 48.6% to 100%. On both univariate and multivariate Cox's regression analyses, lower FEV1/FVC was significantly associated with better survival (hazard ratio of 1.07 and 1.04 and 95% confidential interval of 1.03-1.10 and 1.01-1.08, respectively). Even on analysis with backward selection, FEV1/FVC remained a significant prognostic factor. FEV1/FVC is widely distributed and negatively predicts survival in IPF. A FEV1/FVC should be assessed in "real-world" general practice. Also, the effect of smoking on the clinical course of IPF should be investigated further.

An approach to interpreting restrictive spirometric pattern results in occupational settings.

OBJECTIVES: The aim of this review is to provide an updated overview of definition, epidemiology, diagnostic algorithm and occupational exposures related to abnormal restrictive spirometrical pattern (RSP) in order to improve the correct interpretation of spirometry test results by occupational healthcare providers. METHODS: A review of the scientific English literature of the last 25 years was carried out with MEDLINE and related keywords [(restricti* AND spirometr*) AND occupational]. The first step analysis covered 40 studies and the second step the reference list. Results are presented in four major aims and subquestions. RESULTS: A spirometrical pattern of reduced VC (Vital Capacity), together with a normal FEV1 (Forced Expiratory Volume in 1 Second)/VC ratio, is suggestive, though not diagnostic of restrictive ventilatory defect (RVD). The prevalence of RSP is high in some studies, comparable to obstructive pattern, and could be associated to chronic medical conditions (diabetes, congestive heart failure, obesity, hypertension) as well as to increased risk of mortality and lung cancer. In order to predict true restrictive defect [TLC-(Total Lung Capacity)

Effects of blood lead levels on airflow limitations in Korean adults: findings from the 5th KNHNES 2011.

This study aimed to examine whether blood levels of heavy metals, such as lead, mercury and cadmium, are related with pulmonary function in Korean adults. This investigation included 870 Korean adults (≥ 40 years) who received pulmonary function testing in the Korea National Health and Nutrition Examination Survey (KNHANES) V-2, 2011. Data of blood levels of heavy metals, pulmonary function tests and anthropometric measurements were acquired. Blood lead levels showed inverse correlations with the FEV1/FVC ratio before (r = -0.276, p < 0.001) and after adjustment of multiple compounding factors (r = -0.115, p = 0.001). A logistic multiple regression analysis revealed that blood lead levels were a significant influencing factor for the FEV1/FVC ratio (ß = -0.017, p = 0.001, adjusted R(2) = 0.267). The odds ratios (ORs) for the FEV1/FVC ratio were significantly lower in the highest tertile group of the blood lead levels than in the lowest tertile group in Model 1 (OR = 0.007, 95% CI = 0.000-0.329) and Model 2 (OR = 0.006, 95% CI = 0.000-0.286). These findings imply that environmental exposure to lead might be an important factor that may cause airflow limitations in Korean adults.

Genome-wide association study of lung function phenotypes in a founder population.

BACKGROUND: Lung function is a long-term predictor of mortality and morbidity. OBJECTIVE: We sought to identify single nucleotide polymorphisms (SNPs) associated with lung function. METHODS: We performed a genome-wide association study (GWAS) of FEV1, forced vital capacity (FVC), and FEV1/FVC in 1144 Hutterites aged 6 to 89 years, who are members of a founder population of European descent. We performed least absolute shrinkage and selection operation regression to select the minimum set of SNPs that best predict FEV1/FVC in the Hutterites and used the GRAIL algorithm to mine the Gene Ontology database for evidence of functional connections between genes near the predictive SNPs. RESULTS: Our GWAS identified significant associations between FEV1/FVC and SNPs at the THSD4-UACA-TLE3 locus on chromosome 15q23 (P = 5.7 × 10(-8) to 3.4 × 10(-9)). Nine SNPs at or near 4 additional loci had P < 10(-5) with FEV1/FVC. Only 2 SNPs were found with P < 10(-5) for FEV1 or FVC. We found nominal levels of significance with SNPs at 9 of the 27 previously reported loci associated with lung function measures. Among a predictive set of 80 SNPs, 6 loci were identified that had a significant degree of functional connectivity (GRAIL P < .05), including 3 clusters of ß-defensin genes, 2 chemokine genes (CCL18 and CXCL12), and TNFRSF13B. CONCLUSION: This study identifies genome-wide significant associations and replicates results of previous GWASs. Multimarker modeling implicated for the first time common variation in genes involved in antimicrobial immunity in airway mucosa that influences lung function.

Lung function measurements in the Greenlandic Inuit population: results from the Greenlandic health survey 2017-2019.

Background: Little is known about lung function in Inuit. The aim of this study was to describe lung function and the prevalence of obstructive and restrictive lung disease among Inuit in Greenland. Methods: During the 2017-2019 Health Survey, spirometry, with forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio in liters (L), and percent of predicted value (pred%) were recorded according to Global Lung function Initiative standard reference values (GLI). Smoking history was obtained. Obstructive spirometry was defined as FEV1/FVC <70%. Restrictive spirometry was proposed by FVC < 80% and FEV1/FVC >90%. Results: Based on validated spirometries, 795/2084 persons were included in this cross-sectional, descriptive study. Of those, 54.6% were current- and 27.7% former smokers. In Inuit, normal lung function was higher than predicted GLI (FEV1 107.2 pred%/FVC 113.5 pred%). In total, 106 (13.3%) were found to have an obstructive lung function measurement and 11 (1.4%) had a restrictive pattern. Among current smokers, the prevalence of obstructive lung function was 16.4%. An accelerated decline in lung function was observed > 50 years old (y.o), compared to <50 y.o. Conclusion: This study indicates that Inuit has higher absolute lung function values than standard GLI, despite the large proportion of smokers, which indicate a need for Inuit reference values in the daily clinical praxis. The high prevalence of obstructive lung function and rapid decline in lung function indicates the need for fucus on health issues that may affect lung health in Greenland.

The association between cadmium exposure and the risk of chronic obstructive pulmonary disease: A systematic review and meta-analysis.

According to the World Health Organization, chronic obstructive pulmonary disease (COPD) was one of the top ten causes of death worldwide in 2019. The ratio of forced expiratory volume in the first second to forced vital capacity (FEV1/FVC) provides a useful indicator for the diagnosis of COPD. Existing data have demonstrated that cadmium (Cd) exposure is associated with COPD. However, data concerning the incidence and progression of cadmium-induced COPD is inconsistent. To explore the relationship between cadmium exposure and the risk of COPD in humans, through January 12, 2023, we conducted a thorough search of the PubMed, Cochrane, Web of Science, Embase and Scopus databases for relevant material. In this study, a meta-analysis was conducted to evaluate the association between cadmium and COPD. This meta-analysis indicated that exposure to cadmium (per 1 µg/L increase) was associated with reduced FEV1/FVC (% change = -47.54%, 95% CI: -54.99% to -40.09%). Subgroup analysis showed that the combined effect estimates were significantly higher in the COPD patient group (% change = -54.66%, 95% CI: -83.32% to -26.00%) than in the general population (% change = -52.11%, 95%CI: -60.53% to -43.70%). Therefore, we conclude that cadmium exposure is associated with reduced FEV1/FVC, which suggests a risk for COPD.