Factors Affecting Lung Function: A Review of the Literature

Factors related with lung functions among Orang Asli in Tasik Chini, Malaysia: a cross-sectional study

BACKGROUND

Orang Asli lifestyle and household setting may influence their health status especially respiratory system and lung functions. This cross-sectional study was carried out to investigate the status of lung functions of Orang Asli community and the associated factors.

METHODS

Data collection was carried out from November 2017 until May 2018 among 211 Orang Asli respondents aged 18 years old and above, who lived in five villages in Tasik Chini, Pahang. All respondents who fulfilled the inclusion criteria were recruited in this study. Interview-guided questionnaire was administered, and spirometry test that include Forced Expiratory Volume in one second (FEV1), Forced Vital Capacity (FVC), and Peak Expiratory Flow Rate (PEFR) was carried out. Data were analyzed using SPSS software version 23.0. In the first stage, descriptive analysis was done to describe the characteristics of the respondents. In the second stage, bivariable analysis was carried out to compare proportions. Finally, multiple logistic regression was performed to assess the effects of various independent predictors on spirometry parameters.

RESULTS

The respondents' age ranged from 18 to 71 years old in which 50.2% of them were female. The majority ethnicity in Tasik Chini was Jakun tribe (94.3%). More than half of the respondents (52.1%) were current smoker, 5.2% were ex-smoker and 41.7% were non-smoker. More than half of them (62.1%) used woodstove for cooking, compared to only 37.9% used cleaner fuel like Liquefied Petroleum Gas (LPG) as a fuel for everyday cooking activity. The lung function parameters (FEV1 and FVC) were lower than the predictive value, whereas the ratio of Forced Expiratory Volume in one second and Forced Vital Capacity (FEV1/FVC) (%) and PEFR were within the predictive value. The FEV1 levels were significantly associated with age group (18-39 years old) (p = 0.002) and presence of woodstove in the house (p = 0.004). FVC levels were significantly associated with presence of woodstove in the house (p = 0.004), whereas there were no significant associations between all factors and FEV1/FVC levels.

CONCLUSIONS

FEV1 levels were significantly associated with age group 18-39 years old, whereas FVC levels were significantly associated with the presence of woodstove in the house. Thus, environmental interventions such as replacing the use of woodstove with LPG, need to be carried out to prevent further worsening of respiratory health among Orang Asli who lived far from health facilities. Moreover, closer health monitoring is crucial especially among the younger and productive age group.

Higher fluid and lower caloric intakes: associated risk of severe bronchopulmonary dysplasia in ELBW infants

OBJECTIVE

To examine nutritional intake profiles and growth trajectories of extremely low birth weight (ELBW) infants who develop severe bronchopulmonary dysplasia (BPD).

STUDY DESIGN

Case-control study using multiple logistic regression analysis with generalized estimating equations (GEE) to adjust for matching.

RESULTS

Cumulative and mean fluid intakes were higher (p = 0.003) and caloric intakes lower (p < 0.0001) through week two in infants who developed severe BPD (n = 120) versus those without severe BPD (n = 104). Mean caloric intake through week 12 was lower in infants who developed severe BPD (102 ± 10.1 vs. 107 ± 8.5 kcal/kg/day, p < 0.0001). In the logistic regression models, lower mean caloric intake through week 12 was associated with increased risk of developing severe BPD. Linear growth reduced the odds of BPD by ~30% for each Z-score point.

CONCLUSIONS

Higher fluid and lower total caloric intakes and reductions in linear growth were independently associated with an increased risk of developing severe BPD in ELBW infants.

Post-marketing safety of lorlatinib: a real-world study based on the FDA adverse event reporting system

Background

Lorlatinib displays marked systemic and intracranial efficacy against anaplastic lymphoma kinase (ALK) positive non-small cell lung cancer (NSCLC). We aimed to establish the safety profile of lorlatinib based on the Food and Drug Administration Adverse Event Reporting System (FAERS).

Methods

Reports from the FAERS between 2019 and 2023 were collected to conduct the disproportionality analysis. Reporting odds ratio (ROR) was employed to detect the potential adverse events (AEs) related to lorlatinib. The clinical characteristics, age and gender differences, time to onset of AEs were also investigated.

Results

A total of 2,941 AE reports were found to be associated with lorlatinib among the 8,818,870 AE reports obtained from the FAERS database. 167 lorlatinib-related AE signals were identified. The frequently reported AEs including hypercholesterolemia, oedema, and cognitive disorder were in line with those observed in clinical trials and drug instruction. However, AEs such as interstitial lung disease and AV block indicated in the drug label require further evaluation. More attention should be paid to the new potential unexpected AEs including pulmonary arterial hypertension and radiation necrosis. Furthermore, we examined the specific high-risk AEs of different ages and genders. In addition, majority of AEs occurred within the first 2 months after lorlatinib initiation with a median onset time of 51 days.

Conclusion

Our study provides valuable insight into the post-marketing safety profile of lorlatinib, which can potentially benefit the rational and safe administration of lorlatinib in the clinic. Further prospective studies are needed to validate the associations between lorlatinib and the identified AEs.

Preserved Ratio Impaired Spirometry (PRISm): A Global Epidemiological Overview, Radiographic Characteristics, Comorbid Associations, and Differentiation from Chronic Obstructive Pulmonary Disease

Preserved Ratio Impaired Spirometry (PRISm) manifests notable epidemiological disparities across the globe, with its prevalence and influential factors showcasing pronounced diversities among various geographical territories and demographics. The prevalence of PRISm fluctuates considerably among regions such as Latin America, the United States, and Asian nations, potentially correlating with a myriad of determinants, including socioeconomic status, environmental factors, and lifestyle modalities. Concurrently, the link between PRISm and health risks and other disorders, especially its distinction and interrelation with chronic obstructive pulmonary disease (COPD), has become a pivotal subject of scientific enquiry. Radiographic anomalies, such as perturbations in the pulmonary parenchyma and structural alterations, are posited as salient characteristics of PRISm. Furthermore, PRISm unveils intricate associations with multiple comorbidities, inclusive of hypertension and type 2 diabetes, thereby amplifying the intricacy in comprehending and managing this condition. In this review, we aim to holistically elucidate the epidemiological peculiarities of PRISm, its potential aetiological contributors, its nexus with COPD, and its association with radiographic aberrations and other comorbidities. An integrative understanding of these dimensions will provide pivotal insights for the formulation of more precise and personalised preventative and therapeutic strategies.

Body mass index affects spirometry indices in patients with chronic obstructive pulmonary disease and asthma

Background: Body mass index (BMI) is known to affect the outcomes of spirometry indices. However, its association with spirometry indices in COPD and asthma is less studied. We aimed to explore the impact of BMI on these patients. Methods: Patients with COPD or asthma who completed bronchodilator tests (BDTs) between 2017 and 2021 were reviewed. Spirometry indices were compared among patients with COPD or asthma that were subclassified as underweight (BMI< 18.5 kg/m2), normal weight (≥18.5 to < 25), overweight (≥ 25 to < 30), and obesity (≥ 30). Results. Results: Analysis was conducted on 3891 COPD patients (age:66.5 ± 7.8 years) and 1208 asthma patients (age:59.7 ± 7.5 years). COPD patients classified as underweight demonstrated significantly lower values of pre-and post FEV1 (L, %), pre-and post FVC (L, %), and pre- and post-FEV1/FVC (all p < 0.05). In contrast, COPD patients who were overweight or obese exhibited higher values for pre-and post FEV1 (L, %), and pre and post FEV1/FVC (all p < 0.05). Within the cohort of asthma patients, those underweight had lower pre-and post FEV1 (L, %), pre and post FVC (L, %), pre and post FEV1/FVC %. Obese asthma patients displayed higher pre and post FEV1/FVC (all p < 0.05). Conclusion: Significant BMI category differences in spirometry indices can be seen in patients with COPD or asthma. Both underweight and obesity could affect the diagnosis and severity of these diseases. Recognizing these effects is essential to better management and diagnosis of these patients.

A pharmacovigilance study of etoposide in the FDA adverse event reporting system (FAERS) database, what does the real world say?

Introduction: Etoposide is a broad-spectrum antitumor drug that has been extensively studied in clinical trials. However, limited information is available regarding its real-world adverse reactions. Therefore, this study aimed to assess and evaluate etoposide-related adverse events in a real-world setting by using data mining method on the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) database. Methods: Through the analysis of 16,134,686 reports in the FAERS database, a total of 9,892 reports of etoposide-related adverse drug events (ADEs) were identified. To determine the significance of these ADEs, various disproportionality analysis algorithms were applied, including the reporting odds ratio (ROR), the proportional reporting ratio (PRR), the Bayesian confidence propagation neural network (BCPNN), and the multi-item gamma Poisson shrinker (MGPS) algorithms. Results: As a result, 478 significant disproportionality preferred terms (PTs) that were identified by all four algorithms were retained. These PTs included commonly reported adverse events such as thrombocytopenia, leukopenia, anemia, stomatitis, and pneumonitis, which align with those documented in the drug's instructions and previous clinical trials. However, our analysis also uncovered unexpected and significant ADEs, including thrombotic microangiopathy, ototoxicity, second primary malignancy, nephropathy toxic, and ovarian failure. Furthermore, we examined the time-to-onset (TTO) of these ADEs using the Weibull distribution test and found that the median TTO for etoposide-associated ADEs was 10 days (interquartile range [IQR] 2-32 days). The majority of cases occurred within the first month (73.8%) after etoposide administration. Additionally, our analysis revealed specific high-risk signals for males, such as pneumonia and cardiac infarction, while females showed signals for drug resistance and ototoxicity. Discussion: These findings provide valuable insight into the occurrence of ADEs following etoposide initiation, which can potentially support clinical monitoring and risk identification efforts.

Spirometric Lung Functions in Type 2 Diabetes Mellitus: A Hospital-Based Study

Objective This cross-sectional case-control study was conducted with the aim to analyze spirometric lung functions in type 2 diabetes mellitus (T2DM) patients and to correlate the spirometric dysfunction with (a) duration of diabetes, b) metabolic control of diabetes, and c) microvascular complications of diabetes. Methods Pulmonary function tests (PFTs) were performed in 50 T2DM patients and 50 normal healthy controls aged <80 years by using an electronic spirometer. The PFTs recorded were as follows: forced vital capacity (FVC), forced expiratory volume in one second (FEV1), FEV1%, forced expiratory flow 25 (FEF25), forced expiratory flow 25-75 (FEF25-75), and peak expiratory flow rate (PEFR). The glycated hemoglobin (HbA1c) of all the patients was measured by affinity chromatography using the NycoCard HbA1C kit. The assessment of diabetic microvascular complications was performed as follows: peripheral neuropathy was done using Michigan Neuropathy Screening Instrument (MNSI), diabetic retinopathy using fundus examination, and diabetic nephropathy using solid phase/sandwich-format/immunometric assay using NycoCard U-albumin kit. PFTs of diabetic patients and controls were compared by applying an independent sample t-test. The correlation between FVC and FEV1, and HbA1c and duration of illness in diabetic patients was analyzed by applying the Pearson coefficient. Results  The cases had low FVC (103.82 ±24.43 vs. 116.08 ±13.66), FEV1 (101.36 ±24.23 vs. 110.26 ±14.39), FEV1% (97.56 ±8.64 vs. 103.84 ±5.06), PEFR (101.52 ±27.18 vs. 116.96 ±14.96), and FEF 25-75 (73.56 ±29.19 vs. 98.40 ±14.45) compared to controls, and the difference was statistically significant. A significant negative correlation was found between spirometry parameters and duration of illness as well as HbA1c. Spirometric lung dysfunction also negatively correlated with microvascular complications of diabetes. Among various microvascular complications, retinopathy correlated best with various spirometric parameters. Conclusion Based on our findings, T2DM patients had a significant decrease in their spirometric indices. The pattern of spirometric dysfunction was suggestive of "mixed ventilatory dysfunction". The study results highlight the need to include PFTs in the periodic check-up as part of the comprehensive management of diabetic patients. Hence, pulmonary function should be included in the periodic comprehensive diabetic check for the holistic management of these patients.

A Differential Inertial Wearable Device for Breathing Parameter Detection: Hardware and Firmware Development, Experimental Characterization

Breathing monitoring is crucial for evaluating a patient's health status. The technologies commonly used to monitor respiration are costly, bulky, obtrusive, and inaccurate, mainly when the user moves. Consequently, efforts have been devoted to providing new solutions and methodologies to overcome these limitations. These methods have several uses, including healthcare monitoring, measuring athletic performance, and aiding patients with respiratory diseases, such as COPD (chronic obtrusive pulmonary disease), sleep apnea, etc. Breathing-induced chest movements can be measured noninvasively and discreetly using inertial sensors. This research work presents the development and testing of an inertia-based chest band for breathing monitoring through a differential approach. The device comprises two IMUs (inertial measurement units) placed on the patient's chest and back to determine the differential inertial signal, carrying out information detection about the breathing activity. The chest band includes a low-power microcontroller section to acquire inertial data from the two IMUs and process them to extract the breathing parameters (i.e., RR-respiration rate; TI/TE-inhalation/exhalation time; IER-inhalation-to-exhalation time; V-flow rate), using the back IMU as a reference. A BLE transceiver wirelessly transmits the acquired breathing parameters to a mobile application. Finally, the test results demonstrate the effectiveness of the used dual-inertia solution; correlation and Bland-Altman analyses were performed on the RR measurements from the chest band and the reference, demonstrating a high correlation (r¯ = 0.92) and low mean difference (MD¯ = -0.27 BrPM (breaths per minute)), limits of agreement (LoA¯ = +1.16/-1.75 BrPM), and mean absolute error (MAE¯ = 1.15%). Additionally, the experimental results demonstrated that the developed device correctly measured the other breathing parameters (TI, TE, IER, and V), keeping an MAE of ≤5%. The obtained results indicated that the developed chest band is a viable solution for long-term breathing monitoring, both in stationary and moving users.

Influences of Two FEV1 Reference Equations (GLI-2012 and GIRH-2017) on Airflow Limitation Classification Among COPD Patients

Objective

Methods

Results

Conclusion

Mediator Effect of Cardiorespiratory Fitness on the Association between Physical Activity and Lung Function in Adults: Cross-Sectional Results from the Epimov Study

We investigated whether cardiorespiratory fitness (CRF) mediates the association between moderate-to-vigorous physical activity (MVPA) and lung function in asymptomatic adults. We examined the cross-sectional results of 1362 adults aged 18–80 years from the Epidemiology and Human Movement Study. Participants were submitted to spirometry to obtain forced vital capacity (FVC) and forced expiratory volume in 1s (FEV1). Additionally, we used cardiopulmonary exercise testing to obtain peak oxygen uptake (V˙O2) as a measure of CRF. Participants used a triaxial accelerometer for 4–7 days to obtain MVPA. Mediation analyses were performed considering the CRF as a mediator, MVPA as an independent variable, and FVC and FEV1 as dependent variables with adjustment for age, sex, and cardiovascular risk score. We aimed to investigate the total (path c) and direct (paths a, b, c’) effects through the regression coefficients. We also examined the indirect effect, which was obtained from the product of the coefficients (path ab). Our sample was composed mainly of overweight and middle-aged women. MVPA was positively related to CRF (path a), as well as CRF and lung function (path b). MVPA also presented a significant positive total effect (path c) in the lung function. However, this relationship became non-significant when CRF was included in the model for both FVC and FEV1 (path c’). We did not observe a direct effect of MVPA on the lung function. In contrast, the indirect effect was significant (path ab). Lastly, CRF mediated 60% of the total effect of MVPA on FVC and 61.9% on FEV1. CRF mediates the relationship between lung function and MVPA in asymptomatic adults. Therefore, our results reinforce the need to include CRF assessment in practice clinical routine and suggest that strategies focusing on CRF might be more promising to prevent respiratory diseases in adults.

Reduced forced vital capacity is independently associated with, aging, height and a poor socioeconomic status: a report from the Tunisian population-based BOLD study

Background

Reduced forced vital capacity (FVC) is a risk factor of all-cause mortality; however, the prevalence and determinants of reduced FVC are not available for the Tunisian population. This study investigated the association of reduced FVC with risk factors and health variables in an urban population of subjects aged ≥ 40 years and living in the city of Sousse in Tunisia.

Methods

A cross-sectional survey was performed using data from the Tunisian Burden of Obstructive Lung Disease (BOLD) study. We defined reduced FVC as a post-bronchodilator FVC below the lower limit of normal using National Health and Nutrition Examination Survey (NHANES) values and Global Lung Function Initiative 2012 equations (GLI 2012) and determined the relation between this finding and the potential risk factors (demographic and socioeconomic factors and the presence of chronic diseases), using multivariable regression analysis.

Results

The prevalence of reduced FVC was 26.6% (176/661) when using NHANES values for white Americans and 14.2% (94/661) using the GLI 2012 equations. Compared to people with normal FVC, those with a reduced FVC were significantly older, taller, had a lower body mass index (BMI), more respiratory symptoms and a higher prevalence of heart disease and hypertension. Multivariable analysis showed that reduced FVC was essentially driven by exposure to biomass smoke for heating, a number of schooling years lower than or equal to 6 years, a childhood history of hunger for a lack of money, aging and height.

Conclusions

The prevalence of reduced FVC is associated with a poor socioeconomic status aging and height.

Tuberculosis Mortality in Children under Fifteen Years of Age: Epidemiological Situation in Colombia, 2010-2018

Pediatric tuberculosis is a serious infectious disease and a hidden global epidemic. The objective of this study was to describe the epidemiological situation of tuberculosis mortality in children under 15 years of age in Colombia in the period 2010-2018. A longitudinal descriptive study was conducted. The variables sex, age groups, and origin were studied. This study had 260 cases for analysis and was carried out in three phases. The first phase was the determination of the sociodemographic and clinical characteristics. The second phase was the construction of indicators by territorial entities. The third phase was stratification into four epidemiological situations according to the mortality rate and years of life lost. The median age was 7 years (range 0-14), 66.5% of cases were pulmonary tuberculosis (97.7% without bacteriological confirmation), 14.3781 years of life lost were recorded (95% CI: 142.811-168.333), and in children under 10-14 years, the loss was 110,057. Amazonas had the highest adjusted YLL rate (3979.7). In total, 36.4% of the territories had a high mortality, and 30.3% adjusted to the situation designated as 1. This is the first study that has used composite indicators to address the problem of premature mortality from childhood tuberculosis in Colombia. Our results allow us to specify that this disease remains a challenge for public health. It requires models of care and differential strategies by region. It also requires ensuring opportunities in diagnosis with sensitive methods, as well as intersectoral work for the optimal approach.

High serum folate level is positively associated with pulmonary function in elderly Korean men, but not in women

A limited number of studies have been conducted on the relationship between serum vitamin levels and pulmonary function, particularly in the elderly population. This study attempted to confirm the association between serum vitamin levels (folate, vitamin A, and vitamin E) and pulmonary function in the elderly population of Korea. A total of 1166 subjects (528 men and 637 women) participated in the Korean National Health and Nutrition Examination Survey from 2016 to 2018. Serum levels of folate, vitamin A, and vitamin E were measured in the subjects. The subjects’ pulmonary function measurement items were as follows: forced vital capacity (FVC), forced expiratory volume in one second (FEV1), forced expiratory volume in one second/forced vital capacity (FEV1/FVC), forced expiratory flow at 25% and 75% of the pulmonary volume (FEF25–75%), forced expiratory volume in 6 s (FEV6), and peak expiratory velocity (PEV). We performed regression analysis considering FEV1, PEV, FVC, FEF25–75%, and FEV1/FVC and FEV6 as dependent variables. Serum vitamin A levels were not associated with pulmonary function. In elderly men, serum vitamin E levels were negatively correlated with FVC [B =  − 0.012, 95% confidence interval (CI) − 0.022 to − 0.003, p = 0.012] and FEV1 (B =  − 0.010, 95% CI − 0.115 to − 0.007, p = 0.028). We confirmed a positive correlation of the serum folate level with FEV1 (B = 0.017, 95% CI 0.004–0.030, p = 0.009), FEV1/FVC (B = 0.003, 95% CI 0.001–0.005, p = 0.007), and FEF25–75% (B = 0.031, 95% CI 0.010–0.053, p = 0.005) in elderly men. This study confirmed that high serum folate levels were positively associated with pulmonary function in elderly men in Korea. Further studies are needed to understand the longitudinal effect of folate and its biological mechanism in pulmonary function.

Sex differences in pulmonary function parameters among Indigenous Australians with and without chronic airway disease

BACKGROUND

Studies assessing normative values and sex differences in pulmonary function test parameters (PFTPs) among Indigenous populations are sparse.

METHODS

PFTPs were compared between male and female Indigenous Australian adults with and without chest radiologically proven chronic airway diseases (CADs).

RESULTS

485 adults (56% were female) with no significant difference in age, body mass index or smoking status between sexes were included. Females displayed a higher prevalence of radiology without CADs compared to males (66 vs. 52%, respectively). Among patients without CADs, after adjustment for age, stature and smoking, males displayed significantly higher absolute values of Forced Vital Capacity (FVC) (mean difference, 0.41L (0.21,0.62), p<0.001) and Forced Expiratory Volume in one second (FEV1) (mean difference 0.27L (0.07,0.47), p<0.001), with no significant difference in FEV1/FVC ratio (mean difference -0.02 (-0.06, 0.02), p = 0.174). Male and female patients with radiologically proven CADs demonstrated lower FEV1/FVC values. However, compared to females, males showed significantly greater reductions in pre- [-0.53 (-0.74, -0.32) vs. -0.29 (-0.42, -0.16), p = 0.045] and post- [-0.51 (-0.72, -0.3) vs. -0.27 (-0.39, -0.14), p = 0.049] bronchodilator FEV1.

CONCLUSIONS

There are significant sex differences in the PFTPs among Indigenous Australians. Recognising these differences may be of value in the accurate diagnosis, management, monitoring and prognostication of CADs in this population.

Effects of exposure to fine particulate matter on the decline of lung function in rural areas in northwestern China

Our aim was to clarify the main factors associated with lung function and to analyze the correlation between fine particulate matter (PM_2.5) and lung function in a rural Chinese population. We analyzed data of 5195 participants in the China Northwest Natural Population Cohort: Ningxia Project who were ≥ 30 years old. They were recruited from 2018 to 2019, underwent spirometry during the physical examination, and completed a self-report questionnaire. A satellite-based spatiotemporal model was used to estimate the 2-year average PM_2.5 exposure based on participants' home addresses. A generalized linear mixed model was used to test the relationship between PM_2.5 concentration and lung function. Sex, age, exposure to cooking oil fumes, and occupational exposure were negatively correlated (P < 0.05) with forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV₁). Educational status, economic level, tea consumption, and alcohol consumption were positively correlated (P < 0.05) with FVC and FEV₁. The adjusted results of each model revealed that FVC and FEV₁ decreased with increased exposure to PM_2.5. There was a strong negative correlation between a PM_2.5 concentration of 35.66 μg/m³ and FVC, FEV1, and FEV1/FVC, with unadjusted hazard ratios of - 0.06 (95% confidence interval, - 0.10 to - 0.01), - 0.13 (- 0.17 to - 0.10), and - 22.10 (- 24.62 to - 19.26), respectively. In conclusion, long-term exposure to high concentrations of ambient PM_2.5 is related to reduce lung function among people in rural areas in northwestern China.

Determinants of Longitudinal Change of Lung Function in Different Gender in a Large Taiwanese Population Follow-Up Study Categories: Original Investigation

Chronic lung disease is associated with tremendous social and economic burden worldwide. The aim of this study was to investigate the sex-specific risk factors for changes in lung function in a large longitudinal study. We included 9059 participants from the Taiwan Biobank. None of the participants had a history of smoking, asthma, emphysema or bronchitis. Lung function was assessed using spirometry measurements of forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1). Change in the FEV1/FVC (ΔFEV1/FVC) was calculated as a follow-up FEV1/FVC minus baseline FEV1/FVC. Linear regression analysis was used to identify associations between variables and ΔFEV1/FVC in the male and female participants. After multivariable adjustments, the male participants (vs. females; p = 0.021) were significantly associated with a low ΔFEV1/FVC. In addition, the male participants with low aspartate aminotransferase (AST) (p = 0.003), high alanine aminotransferase (ALT) (p = 0.006) and a low estimated glomerular filtration rate (eGFR) (p = 0.003) were significantly associated with a low ΔFEV1/FVC. For the female participants, low systolic blood pressure (p = 0.005), low diastolic blood pressure (p = 0.031), low AST (p < 0.001), high ALT (p < 0.001) and a low eGFR (p = 0.001) were significantly associated with a low ΔFEV1/FVC. In this large follow-up study, we found that the male participants had a faster decrease in the FEV1/FVC than the female participants. In addition, liver and renal functions were correlated with changes in lung function in both the male and female participants. Our findings provide useful information on sex-specific changes in lung function.

The Effect of Balloon-Blowing Exercise on Postoperative Pulmonary Functions in Patients Undergoing Total Hip Arthroplasty

General anesthesia, prolonged immobilization, and pain may adversely affect pulmonary function in patients undergoing prosthetic surgery. The aim of this study was to evaluate the effect of balloon-blowing exercises on pulmonary functions in patients undergoing total hip arthroplasty. The patients in the experimental group performed three sets of balloon-blowing exercises in the morning, at noon, and in the evening on the first to third days postoperatively. The increase in forced vital capacity (FVC) values between the control and experimental groups in the postoperative period was statistically significant (p < .001), in favor of the experimental group. The increase in forced expiratory volume during the first second (FEV1)/FVC ratio was found to be significantly higher in the experimental group than in the control group (p < .001). Patients who performed balloon-blowing exercises increased their FVC and FEV1/FVC ratio.

Changes in children's lung function over two decades in relation to socioeconomic, parental and household factors in Wuhan, China

Background

It is important to identify risk and beneficial factors for children's lung function. This study aims to ascertain potential changes in children's lung function in relation to changes in socioeconomic, parental and household factors, based on a comparison between two periods spanning 25 years in Wuhan, the largest metropolis in central China.

Methods

In two cross-sectional studies, lung function measurements and questionnaire surveys were conducted on school-age children in 1993-1996 (Period I) and in 2018 (Period II). Children of 6-12 years old from elementary schools were selected by a multistage sampling method. Demographic information, socioeconomic status, feeding methods, parental illness and behavior patterns, as well as household characteristics, were collected through a questionnaire survey. Spirometric lung function was measured, including forced vital capacity (FVC), forced expiratory volume in the first second (FEV₁), forced expiratory flow at 25% and 75% of the pulmonary volume (FEF25-75), and peak expiratory flow (PEF). Wilcoxon analysis of variances was used to assess the differences in lung function indexes between Period I and Period II. Multiple linear regression models were used to estimate the association of lung function with regard to socioeconomic, parental and household factors, respectively.

Results

Significant prevalence reductions were observed for household coal use, paternal smoking and maternal asthma, while the prevalence increased significantly for children sleeping in their own rooms or own beds and breastfeeding, ventilation use during cooking, and parental education level from Period I to Period II. When adjusted for age, height, weight, sex and other factors assessed in the study, children had significant lower values of FVC, FEV₁, and PEF in Period II than in Period I. Enclosed kitchen was significantly associated with lower lung function in children in Period I. Urban living condition and higher maternal education level were each associated with a higher FVC, while father having no fixed income was associated with a lower FVC and a lower FEV₁, respectively, in Period II. In comparison with Period I, the beneficial impact of urban living and that of breastfeeding were enhanced and the detrimental effect of poor household condition was weakened in Period II.

Conclusions

Lung function was lower in 2018 than in 1993-1996 in school-age children living in Wuhan. Although improvements in urban living and household environmental conditions as well as increased breastfeeding in Period II could have contributed to increased lung function, other unmeasured risk factors may have played a more dominant role in leading to a net decrease in lung function from Period I to Period II. Future studies are needed to identify these risk factors.

Extraction and Analysis of Respiratory Motion Using a Comprehensive Wearable Health Monitoring System

Respiratory activity is an important vital sign of life that can indicate health status. Diseases such as bronchitis, emphysema, pneumonia and coronavirus cause respiratory disorders that affect the respiratory systems. Typically, the diagnosis of these diseases is facilitated by pulmonary auscultation using a stethoscope. We present a new attempt to develop a lightweight, comprehensive wearable sensor system to monitor respiration using a multi-sensor approach. We employed new wearable sensor technology using a novel integration of acoustics and biopotentials to monitor various vital signs on two volunteers. In this study, a new method to monitor lung function, such as respiration rate and tidal volume, is presented using the multi-sensor approach. Using the new sensor, we obtained lung sound, electrocardiogram (ECG), and electromyogram (EMG) measurements at the external intercostal muscles (EIM) and at the diaphragm during breathing cycles with 500 mL, 625 mL, 750 mL, 875 mL, and 1000 mL tidal volume. The tidal volumes were controlled with a spirometer. The duration of each breathing cycle was 8 s and was timed using a metronome. For each of the different tidal volumes, the EMG data was plotted against time and the area under the curve (AUC) was calculated. The AUC calculated from EMG data obtained at the diaphragm and EIM represent the expansion of the diaphragm and EIM respectively. AUC obtained from EMG data collected at the diaphragm had a lower variance between samples per tidal volume compared to those monitored at the EIM. Using cubic spline interpolation, we built a model for computing tidal volume from EMG data at the diaphragm. Our findings show that the new sensor can be used to measure respiration rate and variations thereof and holds potential to estimate tidal lung volume from EMG measurements obtained from the diaphragm.

Lung function and respiratory muscle strength and their relationship with weightlifting strength and body composition in non-athletic males

The aim of this study was to examine whether lung function and respiratory muscle strength are associated with weightlifting strength and body composition in non-athletic males. A total 51 males with resistance training experience participated. One-repetition maximum tests were performed for the bench press, squat and deadlift and body composition was assessed. Lung function was evaluated with a pulmonary testing system and respiratory muscle strength was assessed with a handheld mouth-pressure manometer. Moderate to strong positive relationships were found between all weightlifting strength variables and maximal expiratory pressure (r = 0.36-0.54, p = ≤0.01). Small to strong positive correlations were found between fat-free mass, appendicular lean mass and most lung function variables (r = 0.29-0.54, p ≤ 0.039). However, fat-free mass and appendicular lean mass indexes were only related with respiratory muscle strength and not lung function. Expiratory muscle strength appears to influence weightlifting performance. Special exercises targeting the expiratory muscles may assist with improving weightlifting performance, especially for squats and deadlifts.

Pulmonary function tests in type 2 diabetes: a meta-analysis

OBJECTIVES

The aim of this study was to determine the association between type 2 diabetes (T2D) and pulmonary function tests.

METHODS

After conducting an exhaustive literature search, we performed a meta-analysis. We employed the inverse variance method with a random-effects model to calculate the effect estimate as the mean difference (MD) and 95% confidence interval (CI). We calculated the heterogeneity with the I2 statistic and performed a meta-regression analysis by sex, body mass index (BMI), smoking and geographical region. We also conducted a sensitivity analysis according to the studies' publication date, size of the T2D group and the study quality, excluding the study with the greatest weight in the effect.

RESULTS

The meta-analysis included 66 studies (one longitudinal, two case-control and 63 cross-sectional), with 11 134 patients with T2D and 48 377 control participants. The pooled MD (95% CI) for the predicted percentage of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), forced expiratory flow at 25-75% of FVC, peak expiratory flow, and diffusing capacity of the lung for carbon monoxide were -7.15 (95% CI -8.27, -6.03; p<0.001), -9.21 (95% CI -11.15, -7.26; p<0.001), -9.89 (95% CI -14.42, -5.36; p<0.001), -9.79 (95% CI -13.42, -6.15; p<0.001) and -7.13 (95% CI -10.62, -3.64; p<0.001), respectively. There was no difference in the ratio of FEV1/FVC (95% CI -0.27; -1.63, 1.08; p=0.69). In all cases, there was considerable heterogeneity. The meta-regression analysis showed that between studies heterogeneity was not explained by patient sex, BMI, smoking or geographical region. The findings were consistent in the sensitivity analysis.

CONCLUSIONS

T2D is associated with impaired pulmonary function, independently of sex, smoking, BMI and geographical region. Longitudinal studies are needed to investigate outcomes for patients with T2D and impaired pulmonary function.

Effects of genetics and altitude on lung function

OBJECTIVES

The aim of this work is to present a review on the impact of genetics and altitude on lung function from classic and recent studies.

DATA SOURCE

A systematic search has been carried out in different databases of scientific studies, using keywords related to lung volumes, spirometry, altitude and genetics.

RESULTS

The results of this work have been structured into three parts. First, the relationship between genes and lung function. Next, a review of the genetic predispositions related to respiratory adaptation of people who inhabit high-altitude regions for millennia. Finally, temporary effects and long-term acclimatisation on respiratory physiology at high altitude are presented.

CONCLUSIONS

The works focused on the influence of genetics and altitude on lung function are currently of interest in terms of studying the interactions between genetic, epigenetic and environmental factors in the configuration of the pathophysiological adaptation patterns.

Comparison of inspiratory and expiratory lung and lobe volumes among supine, standing, and sitting positions using conventional and upright CT

Currently, no clinical studies have compared the inspiratory and expiratory volumes of unilateral lung or of each lobe among supine, standing, and sitting positions. In this prospective study, 100 asymptomatic volunteers underwent both low-radiation-dose conventional (supine position, with arms raised) and upright computed tomography (CT) (standing and sitting positions, with arms down) during inspiration and expiration breath-holds and pulmonary function test (PFT) on the same day. We compared the inspiratory/expiratory lung/lobe volumes on CT in the three positions. The inspiratory and expiratory bilateral upper and lower lobe and lung volumes were significantly higher in the standing/sitting positions than in the supine position (5.3–14.7% increases, all P < 0.001). However, the inspiratory right middle lobe volume remained similar in the three positions (all P > 0.15); the expiratory right middle lobe volume was significantly lower in the standing/sitting positions (16.3/14.1% decrease) than in the supine position (both P < 0.0001). The Pearson’s correlation coefficients (r) used to compare the total lung volumes on inspiratory CT in the supine/standing/sitting positions and the total lung capacity on PFT were 0.83/0.93/0.95, respectively. The r values comparing the total lung volumes on expiratory CT in the supine/standing/sitting positions and the functional residual capacity on PFT were 0.83/0.85/0.82, respectively. The r values comparing the total lung volume changes from expiration to inspiration on CT in the supine/standing/sitting positions and the inspiratory capacity on PFT were 0.53/0.62/0.65, respectively. The study results could impact preoperative CT volumetry of the lung in lung cancer patients (before lobectomy) for the prediction of postoperative residual pulmonary function, and could be used as the basis for elucidating undetermined pathological mechanisms. Furthermore, in addition to morphological evaluation of the chest, inspiratory and expiratory upright CT may be used as an alternative tool to predict lung volumes such as total lung capacity, functional residual capacity, and inspiratory capacity in situation in which PFT cannot be performed such as during an infectious disease pandemic, with relatively more accurate predictability compared with conventional supine CT.

Cohort Differences in Maximal Physical Performance: A Comparison of 75- and 80-Year-Old Men and Women Born 28 Years Apart

BACKGROUND

Whether increased life expectancy is accompanied by increased functional capacity in older people at specific ages is unclear. We compared similar validated measures of maximal physical performance in 2 population-based older cohorts born and assessed 28 years apart.

METHOD

Participants in the first cohort were born in 1910 and 1914 and were assessed at age 75 and 80 years, respectively (N = 500, participation rate 77%). Participants in the second cohort were born in 1938 or 1939 and 1942 or 1943 and were assessed at age 75 and 80 years, respectively (N = 726, participation rate 40%). Participants were recruited using a population register and all community-dwelling persons in the target area were eligible. Both cohorts were interviewed at home and were examined at the research center with identical protocols. Maximal walking speed, maximal isometric grip and knee extension strength, forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) were assessed. Data on non-participation were systematically collected.

RESULTS

Walking speed was on average 0.2-0.4 m/s faster in the later than earlier cohort. In grip strength, the improvements were 5%-25%, and in knee extension strength 20%-47%. In FVC, the improvements were 14-21% and in FEV1, 0-14%.

CONCLUSIONS

The later cohort showed markedly and meaningfully higher results in the maximal functional capacity tests, suggesting that currently 75- and 80-year-old people in Finland are living to older ages nowadays with better physical functioning.

Differences in Lung and Lobe Volumes between Supine and Standing Positions Scanned with Conventional and Newly Developed 320-Detector-Row Upright CT: Intra-Individual Comparison

BACKGROUND

No clinical studies to date have compared unilateral lung or lobe volumes between the supine and standing positions.

OBJECTIVES

To compare lung/lobe volumes on computed tomography (CT) between these two positions and evaluate the correlation between the total lung volume and total lung capacity (TLC) on pulmonary function tests (PFTs).

METHODS

Thirty-two asymptomatic volunteers underwent both conventional CT (supine position) and upright CT (standing position), during deep inspiration breath-hold, and PFTs on the same day. We measured lung/lobe volumes on CT in each position. Paired t tests were used for statistical analysis.

RESULTS

The volumes of the total lung (10.9% increase), right lung (10.3% increase), right upper lobe (8.6% increase), right lower lobe (14.6% increase), left lung (11.6% increase), left upper lobe (7.1% increase), and left lower lobe (16.0% increase) were significantly greater in the standing position than in the supine position (all p < 0.0001). The right middle lobe volume was similar between the two positions (p = 0.16). Intraclass correlation coefficients for agreement between total lung volumes on CT in the supine/standing positions and the TLC on PFT were 0.891/0.938, respectively.

CONCLUSIONS

While the volumes of the bilateral upper and lower lobes and bilateral lungs were significantly greater in the standing than in the supine position, with lower lobes showing larger changes, the right middle lobe volume did not change significantly between positions. The total lung volume on upright CT in the standing position was more similar to TLC on PFT than that in the supine position.

Muscle metabolomics analysis reveals potential biomarkers of exercise‑dependent improvement of the diaphragm function in chronic obstructive pulmonary disease

Decreased diaphragm function is a crucial factor leading to reduced ventilatory efficiency and worsening of quality of life in chronic obstructive pulmonary disease (COPD). Exercise training has been demonstrated to effectively improve the function of the diaphragm. However, the mechanism of this process has not been identified. The emergence of metabolomics has allowed the exploration of new ideas. The present study aimed to analyze the potential biomarkers of exercise-dependent enhancement of diaphragm function in COPD using metabolomics. Sprague Dawley rats were divided into three groups: COPD + exercise group (CEG); COPD model group (CMG); and control group (CG). The first two groups were exposed to cigarette smoke for 16 weeks to establish a COPD model. Then, the rats in the CEG underwent aerobic exercise training for 9 weeks. Following confirmation that exercise effectively improved the diaphragm function, a gas chromatography tandem time-of-flight mass spectrometry analysis system was used to detect the differential metabolites and associated pathways in the diaphragm muscles of the different groups. Following exercise intervention, the pulmonary function and diaphragm contractility of the CEG rats were significantly improved compared with those of the CMG rats. A total of 36 different metabolites were identified in the comparison between the CMG and the CG. Pathway enrichment analysis indicated that these different metabolites were involved in 17 pathways. A total of 29 different metabolites were identified in the comparison between the CMG and the CEG, which are involved in 14 pathways. Candidate biomarkers were selected, and the pathways analysis of these metabolites demonstrated that 2 types of metabolic pathways, the nicotinic acid and nicotinamide metabolism and arginine and proline metabolism pathways, were associated with exercise-induced pulmonary rehabilitation.

Obesity Does Not Increase the Risk of Asthma Readmissions

The relationship between obesity and asthma exacerbations is still under debate. The aim of our work is to analyse the relationship between obesity and hospital re-admissions in asthmatics. A review was retrospectively performed on all hospital admissions of adult patients due to asthma exacerbation occurring in our hospital for 11 years. All those cases with asthma as the first diagnosis in the discharge report were included, or those with asthma as the second diagnosis provided when the first diagnosis was respiratory infection or respiratory failure. Only the first hospital admission of each patient was included in this study. The Odds Ratios of a higher incidence of early/late readmissions due to asthma exacerbation were calculated using a binary logistic regression, using the body mass index (BMI) as independent variable, adjusted for all the variables included in the study. The study included 809 patients with a mean age of 55.6 years, and 65.2% were female. The majority (71.4%) were obese or overweight. No significant relationship was observed in the univariate or multivariate analyses between overweight or obesity and the early or late hospital readmissions due to asthma. Therefore, obesity does not seem to be a determining factor in the risk of asthma exacerbations.

Lung Function and Respiratory Symptoms after Tuberculosis in an American Indian Population. The Strong Heart Study

Rationale: Permanent lung function impairment after active tuberculosis infection is relatively common. It remains unclear which spirometric pattern is most prevalent after tuberculosis.Objectives: Our objective was to elucidate the impact of active tuberculosis survival on lung health in the Strong Heart Study (SHS), a population of American Indians historically highly impacted by tuberculosis. As arsenic exposure has also been related to lung function in the SHS, we also assessed the joint effect between arsenic exposure and past active tuberculosis.Methods: The SHS is an ongoing population-based, prospective study of cardiovascular disease and its risk factors in American Indian adults. This study uses tuberculosis data and spirometry data from the Visit 2 examination (1993-1995). Prior active tuberculosis was ascertained by a review of medical records. Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and FEV1/FVC were measured by spirometry. An additional analysis was conducted to evaluate the potential association between active tuberculosis and arsenic exposure.Results: A history of active tuberculosis was associated with reduced percent predicted FVC and FEV1, an increased odds of airflow obstruction (odds ratio = 1.45, 95% confidence interval = 1.08-1.95), and spirometric restrictive pattern (odds ratio = 1.73, 95% confidence interval = 1.24-2.40). These associations persisted after adjustment for diabetes and other risk factors, including smoking. We also observed the presence of cough, phlegm, and exertional dyspnea after a history of active tuberculosis. In the additional analysis, increasing urinary arsenic concentrations were associated with decreasing lung function in those with a history of active tuberculosis, but a reduced odds of active tuberculosis was found with elevated arsenic.Conclusions: Our findings support existing knowledge that a history of active tuberculosis is a risk factor for long-term respiratory impairment. Arsenic exposure, although inversely associated with prior active tuberculosis, was associated with a further decrease in lung function among those with a prior active tuberculosis history. The possible interaction between arsenic and tuberculosis, as well as the reduced odds of tuberculosis associated with arsenic exposure, warrants further investigation, as many populations at risk of developing active tuberculosis are also exposed to arsenic-contaminated water.

Advances in spirometry testing for lung function analysis

Introduction: Spirometry, the most common lung function test, is used to evaluate individuals with respiratory complaints or known respiratory disease. However, its underutilization and the misinterpretation of its parameters are causes for concern. Areas covered: This review describes new spirometry-derived metrics, new reference equations, recent recommendations for presentation of results, recent spirometry-based prevalence studies, and technological advances in spirometry equipment. Expert opinion: The underutilization of spirometry can be overcome by increasing access to portable, hand-held, and user-friendly spirometers, together with strategies that increase awareness of the importance of spirometry. New metrics derived from spirometry, together with traditional spirometric criteria, can identify individuals with structural lung disease and respiratory morbidity. Some problems with the reference equations were solved by the Global Lung Function Initiative (GLI), which covers a wider age range and more ethnic groups and provides limits of normality using the z-score. Despite these advantages, the GLI equations lack data from large populations (especially those from Africa, South Asia, and Latin America) and greater representation of older people. Another disadvantage attributed to the GLI is the lack of predicted values for peak expiratory flow and other airflows, limiting the interpretation of the maximal expiratory flow-volume curve.