Decrease In Peak Expiratory Flow Research Articles

Abstract P390: Gender And Strain Background Affect Cardiopulmonary Function In Col4a3 -/- Alport Mice

Background: Alport syndrome (AS) is a hereditary form of chronic kidney inflammation that results in renal failure (RF). Our group previously reported that Col4a3 -/- mice, a model of AS and RF, on 129J background exemplified multiple features of heart failure with preserved ejection fraction (HFpEF). This study investigates the effect of 3 different genetic backgrounds on cardiopulmonary function in Col4a3 -/- mice. Methods: Male and female Col4a3 -/- (Alport) and WT mice on 3 different genetic backgrounds, 129x1/SvJ, C57Bl/6 and BALBC, were examined using echocardiography, whole body plethysmography (WBP) and pressure-volume (PV) loop analysis. Ttest was used for statistical analysis. Four groups per strain were used (n= 4 to 15 per group). Results: Compared with their respective age-matched WT controls, both male and female 8-week-old Col4a3 -/- 129x1/SvJ mice demonstrated impaired systolic function (EF of 56% to 43.7%, p=0.0018 for females and 50.9% to 42% for males, p=0.044; SV, CO, p<0.05) and diastolic dysfunction (increased IVRT from 15.32ms to 21.72ms, p=0.0009 for females; 16.57ms to 26.21ms, p<0.0001 for males; increased MPI, P<0.05). Additionally, PV loop analysis showed an increased EDPVR and end diastolic pressure, prolonged time constant of LV relaxation, and decreased CO and SV (p<0.05). However for Col4a3 -/- BalbC (8-week-old) and Col4a3 -/- C57Bl/6 (20-week-old) strains, only females exhibited systolic (BalbC: EF% 51% to 45.66%, p=0.106 for females and 43.5% to 40.8% for males, p=0.508; B6: EF% 51.30% to 40.80% p=0.024 for females and 48.43% to 40.91%, p=0.3098 for males; SV, CO, p<0.05) and diastolic dysfunction (IVRT from 15.96ms to 24.91ms for Balb/C and 18.20ms to 25.63ms for B6, p<0.05). Male Col4a3 -/- BalbC had an increase in minimum pressure and end-systolic pressure, and an increased pressure at dV/dt-max. Male Col4a3 -/- C57Bl/6 mice had an increased ESPVR slope (p<0.05). All strains except BalbC males demonstrated alterations (p<0.05) in pulmonary function including decreased ventilation rate (MV, mL/min) and respiratory frequency (BPM), decreased peak expiratory flow, EF50, increased expiratory time, relaxation time, inspiratory time, and time of pause at end-of-expiration. Conclusion: Both male and female Col4a3 -/- 129x1/SvJ mice demonstrated impaired cardiopulmonary viability. However, Col4a3 -/- mice on BalbC or C57Bl/6 strains had cardiopulmonary deficits only in females.

A cross sectional study of the morbidity pattern among stone quarry workers and their associated risk factors

Background: Construction sector is a thriving industry which comprises most of the unorganized workers and providing widespread opportunities for employment of most of the poorest and marginalized sections of society in India. The workers are more susceptible to various occupational hazards due to working conditions in dusty environment. This study is proposed to identify the morbidity pattern, availability and usage of safety measures, health care seeking behaviour and health care facilities at the quarry site.Methods: A cross sectional study was conducted among the stone quarry workers of Maduranthakam area in Kancheepuram district from February 2018 to May 2018. The sample size was calculated as 94 and five quarries were selected randomly. The study tool was interview based semi structured questionnaire and clinical examination. Appropriate descriptive and inferential statistics like Chi square test, Fischer’s exact test was done to determine significant association (p<0.05).Results: The common morbidities among the participants were abdominal conditions (54%), injuries (34%) and musculoskeletal disorders (27%). One in five individuals had respiratory problems and those with breathing difficulty had decreased peak expiratory flow rate. Usage of personal protective equipments is low and about 63.8% of them were using government health care facilities.Conclusions: Increasing demand for stone and aggregates has led to extensive stone quarrying operations. Awareness and enforcement of personal protective equipment, vaccination against diseases like tetanus, periodic health check- ups should be enforced for people working in quarries.

Evaluation of muscle-skeletal strength and peak expiratory flow in severely malnourished inpatients with anorexia nervosa: A pilot study

ObjectivesAnorexia nervosa is a complex psychiatric disorder that can lead to specific somatic complications. Malnutrition is frequent and can involve a decrease of mobility, up to functional impotence, in individuals with extremely severe cases. The aim of this pilot study was to examine muscle strength and peak expiratory flow (PEF) in severely undernourished patients with anorexia nervosa at admission and after 5 wk of renutrition by tube feeding, and to find the clinical and biological correlates of muscle-strength impairment. MethodsA prospective observational study was conducted over 6 mo. Manual muscle testing, measures of PEF, and clinical and biologic assessments were performed at baseline and after 5 wk of renutrition. ResultsTwenty-three extremely malnourished female participants (mean body mass index: 11.4 ± 1.3 kg/m2) were included. All participants had global impairment in muscle strength (manual muscle testing: 37.7 ± 7.7) and PEF (253.3 ± 60 mL/min) at admission. Muscle weakness was higher in axial than peripheral muscle groups (P < 0.01), with no significant difference between proximal and distal muscles (P > 0.05). Muscle strength at admission was significantly associated with severity of undernourishment (body mass index and albumin) and transaminitis (P < 0.05). At follow-up, musculoskeletal strength and PEF were significantly improved after partial weight recovery (P < 0.01). ConclusionsExtremely undernourished people with anorexia nervosa present a decrease of PEF and musculoskeletal strength predominant on axial muscles. Both are associated with severity of malnutrition and liver damage. Partial recovery was observed after 5 wk of enteral nutrition.

The effect of acute outdoor air pollution on peak expiratory flow in individuals with asthma: A systematic review and meta-analysis

ObjectivesAcute exposures to outdoor air pollution have been shown to reduce lung function in children with asthma, but the effect on adults with asthma has not been established in a meta-analysis. The objective of this study was to conduct a systematic literature review and meta-analysis of studies that assessed the relationship of outdoor air pollution and peak expiratory flow (PEF) in adults with asthma. MethodsStudies that contained data on outdoor air pollution levels (PM10, PM2.5, or NO2) and PEF in adults with asthma were eligible for inclusion. Effect estimates were quantified for each air pollution measure using random effects models. Heterogeneity was investigated with the Q-test and I2 statistics. Meta-regression and subgroup analyses were conducted to determine differences in effect by air pollution measures and the inclusion of smokers. ResultsA total of 22 effect estimates from 15 studies were included in this review. A 10 μg/m3 increase in acute PM10 exposure was associated with a −0.19 L/min (95% CI: 0.30, −0.09) change in PEF. For both PM10 and PM2.5, the inclusion of current smokers was a significant source of heterogeneity among studies (meta-regression: p = 0.04 and p = 0.03). Among studies that only included non-smokers, a 10 μg/m3 increase in acute exposure to PM10 and PM2.5 was associated with changes in PEF of −0.25 L/min (95% CI: 0.38, −0.13) and −1.02 L/min (95% CI: 1.79, −0.24), respectively. ConclusionsThis study provides evidence that acute increases in PM10 and PM2.5 levels are associated with decreases in PEF in adults with asthma, particularly among non-smokers.

Does The Mixed Relay Triathlon Affect Respiratory Function In Healthy Junior Triathletes?

Exercise-induced bronchoconstriction (EIB) is a transient narrowing of the airway that can be attributed to heavy ventilation associated with sustained high intensity exercise greater than 8 min. High aerobic and ventilatory training demands can exacerbate the EIB response and lead to prevalence of EIB in endurance athletes like triathletes. The mixed relay triathlon, due to its high intensity and short duration format, will induce heavy ventilation that could lead to EIB. However, no research at present has determined the influence of a mixed relay on respiratory function and baseline spirometry measures which influence EIB. PURPOSE: To determine severity and prevalence of EIB in healthy triathletes competing in a mixed relay and understand if baseline spirometry is predictive of the EIB response and race performance. METHODS: Seven males (17.7 ± 0.4 years, 183.7 ± 3.0 cm) and 5 females (17.6 ± 0.6 years, 171.1 ± 2.7 cm) competed in the Canadian Championships (300m swim, 6km bike, 1.6km run). Spirometry measures of Forced Expiratory Volume in 1 sec (FEV1), Forced Vital Capacity (FVC), FEV1/FVC (%), Forced Expiratory Flow at 50% FVC (FEF50), FEF 25-75% and Peak Expiratory Flow (PEF) was performed before warm up and 5 min post-race. Measures were calculated as % delta change (for EIB determination) and in raw units to determine pre-post differences in measures via paired sample t-tests. RESULTS: Mean race time was 22.4 ± 1.5 min including transitions (swim 4.5 ± 0.5 min, bike 10.4 ± 0.7 min, run 6.1 ± 0.6 min). No spirometry measure was significantly decreased post-race. One athlete had mild EIB (% decrease in FEV1 between 10 and 25%) and 2 athletes had a baseline FEV1/FVC ratio <0.7. Percent delta change in PEF and FEF 25-75% were correlated to finish time (r=-0.78, r=-0.83, p<0.05 respectively). CONCLUSION: An all-out 20 min ultra-short triathlon does not negatively affect respiratory function in young healthy junior triathletes. It maybe that the decrease in PEF and FEF 25-75 affected finish time due to reduced airway function affecting exercise intensity. The low prevalence of EIB compared to older endurance athletes supports the late onset of EIB in endurance athletes (> 25 years) although the 2 athletes with <0.7 resting FEV1/FVC ratios show signs of underlying airway obstruction.

Tiotropium in children and adolescents with asthma

BackgroundAsthma is a major cause of morbidity in children, despite the availability of various treatments. In adults, tiotropium—a long-acting muscarinic antagonist—as add-on therapy to an inhaled corticosteroid with or without a long-acting β2-agonist provides clinical benefit with a safety profile similar to placebo. ObjectiveTo review published evidence on the efficacy and safety of tiotropium as add-on a long-acting muscarinic antagonist therapy in children and adolescents with asthma that is uncontrolled despite use of an inhaled corticosteroid with or without additional controller medication(s). MethodsWe searched PubMed from inception until June 12, 2018, for randomized controlled trials of children and adolescents aged 1 to 17 years treated with tiotropium and reporting a primary outcome of any pulmonary function test and a secondary outcome of adverse events. ResultsOverall, 7 randomized controlled trials of 1902 preschool children (aged 1-5 years; n = 102), school-age children (aged 6-11 years; n = 905), and adolescents (aged 12-17 years; n = 895) with moderate to severe asthma were included in the analysis. Once-daily tiotropium (5, 2.5, or 1.25 μg) improved lung function parameters, including peak and trough forced expiratory volume in 1 second, vs placebo. Commonly reported adverse events across treatment groups included asthma worsening or exacerbations, decreased peak expiratory flow rate, nasopharyngitis, viral respiratory tract infection, and respiratory tract infection. ConclusionOnce-daily tiotropium as add-on therapy is efficacious and safe in adolescents and children with moderate to severe asthma. These results support the expanded indication by regulatory authorities for add-on tiotropium in patients 6 years or older.

Serial Changes in Pulmonary Function Testing in A Patient with Tracheobronchial Amyloidosis: Relevance for Early Diagnosis

Amyloidosis is a disease of abnormal extracellular deposition of proteins within tissues, commonly affecting solid organs such as the heart, liver, and kidneys. Less commonly, amyloidosis may affect the proximal tracheobronchial tree. Clinical symptoms are vague and may include shortness of breath, stridor, hoarseness. Pulmonary function testing at the time of diagnosis usually reveals an obstructive pattern. Diagnosis is difficult, and patients with tracheobronchial amyloidosis are frequently misdiagnosed with asthma or chronic obstructive pulmonary disease. Early changes in pulmonary function testing in patients with tracheobronchial amyloidosis have not been described. We present a case of a firefighter who with obstructive symptomatology who was subsequently diagnosed with proximal tracheobronchial amyloidosis. As a component of his occupational health surveillance, yearly examinations and pulmonary function testing had been performed. Serial pulmonary function testing dating back fourteen years prior to diagnosis reveal an early decrease in peak expiratory flow. Over time and in retrospect, progressive blunting of the expiratory limb of his flow-volume loops is identified beginning ten years prior to presentation. These changes significantly predated his clinical symptomatology and may be useful for early identification of patients with tracheobronchial amyloidosis. The relationship between chronic smoke inhalation and the development of tracheobronchial amyloidosis is unclear.

Associations of chemical composition and sources of PM2.5 with lung function of severe asthmatic adults in a low air pollution environment of urban Nagasaki, Japan

Previous studies have linked ambient PM2.5 to decreased pulmonary function, but the influence of specific chemical elements and emission sources on the severe asthmatic is not well understood. We examined the mass, chemical constituents, and sources of PM2.5 for short-term associations with the pulmonary function of adults with severe asthma in a low air pollution environment in urban Nagasaki, Japan. We recruited 35 asthmatic adults and obtained the daily record of morning peak expiratory flow (PEF) in spring 2014–2016. PM2.5 filters were extracted from an air quality monitoring station (178 days) and measured for 27 chemical elements. Source apportionment was performed using Positive Matrix Factorization (PMF). We fitted generalized linear model with generalized estimating equation (GEE) method to estimate changes in PEF (from personal monthly maximum) and odds of severe respiratory deterioration (first ≥ 15% PEF reduction within a 1-week interval) associated with mass, constituents, and sources of PM2.5, with adjustment for temperature and relative humidity. Constituent sulfate (SO42−) and PM2.5 from oil combustion and traffic were associated with reduced PEF. An interquartile range (IQR) increase in SO42− (3.7 μg/m3, average lags 0–1) was associated with a decrease of 0.38% (95% confidence interval = −0.75% to −0.001%). An IQR increase in oil combustion and traffic-sourced PM2.5 (2.64 μg/m3, lag 1) was associated with a decrease of 0.33% (−0.62% to −0.002%). We found a larger PEF decrease associated with PM2.5 from dust/soil on Asian Dust days. There was no evidence linking total mass and metals to reduced pulmonary function. The ventilatory capacity of adults with severe asthma is susceptible to specific constituents/sources of PM2.5 such as sulfate and oil combustion and traffic despite active self-management of asthma and low air pollution levels in the study location.

Electroacupuncture at "Zusanli" (ST36) and "Chize" (LU5) of mother rats exposed to nicotine during pregnancy and lactation has a protective effect on development of lung function and morphology in neonatal rats

To compare the different effect of electroacupuncture (EA) at "Zusanli" (ST36) and "Chize" (LU5) of mother rats exposed to Nicotine during pregnancy and lactation on lung function and morphological changes in offspring rats, so as to explore the most effective acupoint for improving the development of lung in neonatal rats. A total of 24 female pregnancy SD rats were randomly divided into 4 groups: normal control, model, EA-ST36 and EA-LU5 (n＝6 rats in each group). Rats of the normal group were treated by subcutaneous injection of normal saline, and those of the other 3 groups treated by subcutaneous injection of nicotine (1 mg•kg－1•d－1) beginning from the 6th day to about the 21st day of pregnancy (childbirth day) for nicotine exposure during pregnancy and lactation. The daily EA treatment (2 Hz /15 Hz，1 mA) was applied to bilateral ST36 and LU5 for 20 min, beginning from the 6th day of pregnancy to the 21st day (childbirth day). The lung function of the offspring rats including the peak inspiratory flow (PIF), peak expiratory flow (PEF), lung resistance (RL), exhalation resistance (RE)and lung dynamic compliance (Cdyn) was detected by using a lung function analysis system. Histopathological changes (severity of alveolarization) of the offspring rats' lung tissue were observed under microscope after H．E. stain. Compared with the normal group, the PIF, RL and RE values were significantly increased (P<0.01), and PEF and Cdyn values significantly decreased in the model group (P<0.01). The alveolar diameter in the model group was evidently increased relevant to the normal group (P<0.01). Following the intervention, modeling induced increase of PIF, RL, RE and alveolar diameter and decrease of PEF and Cdyn values in the EA-ST36 group, and the increased PIF, RL and RE levels in the EA-LU5 group were obviously suppressed relevant to the model group (P<0.01, P<0.05). Additionally, modeling induced obvious congestion and edema of the alveolar wall, alveolar deformation, rupture and fusion, and reduction of the number of the pulmonary alveoli were evidently milder in both EA-ST36 and EA-LU5 groups. No significant differences were found between the EA-ST36 and EA-LU5 groups in the abovementioned 5 indexes of pulmonary function and alveolar diameter (P>0.05)．. EA of ST36 and LU5 of mother rats experiencing nicotine exposure during pregnancy and lactation can improve the lung function and morphological changes in neonatal rats, and the effect of ST36 is relatively better.

Safety of tiotropium in patients with asthma.

Given the high proportion of patients with asthma who remain uncontrolled despite controller treatment, there remains a need for the development of more effective treatment options with a proven safety and tolerability profile. Recently, asthma guidelines have evolved to incorporate new therapies, including long-acting muscarinic antagonists (LAMAs) and biologics. Here we focus on the safety profile of tiotropium, a LAMA, using data from the large-scale UniTinA-asthma® clinical trial program, which investigated the use of tiotropium in over 6000 patients with asthma who remained symptomatic despite receiving inhaled corticosteroids (ICS) maintenance therapy, with or without other adjunct therapies. The large number of patients included allows robust analysis of safety and tolerability. Overall, a similar incidence of patients reporting any adverse event (AE) was observed in the tiotropium (5 µg and 2.5 µg) and placebo groups. Asthma worsening, decreased peak expiratory flow, and upper respiratory tract infections were the most frequently reported AEs. Serious AEs (SAEs) and investigator-defined drug-related AEs were infrequently reported across all treatment groups, including the placebo group, and there were no deaths in any study. Reports of side effects typically associated with anticholinergic drugs, such as dry mouth and urinary retention, were either infrequent or not reported in children, adolescents or adults. The similar proportions of tiotropium-versus placebo-treated patients reporting AEs and SAEs in African-American and Japanese populations, as well as in elderly patients, contribute to the accumulating evidence of the safety and tolerability of tiotropium across broad ethnic and age populations.

Acute effects of electronic and tobacco cigarettes on vascular and respiratory function in healthy volunteers: a cross-over study.

To assess the acute effects of nicotine-containing electronic cigarettes versus tobacco smoking on vascular and respiratory function and circulating microparticles, particularly platelet microparticles (PMPs, biomarker of haemostasis/thrombosis) and endothelial microparticles (EMPs, biomarker of endothelial function). Heart rate (HR), blood pressure, reactive hyperaemia index (RHI, microvascular reactivity), augmentation index (arterial stiffness) and respiratory function were assessed in 20 smokers immediately before and after electronic cigarettes use and tobacco smoking. The number of microparticles was determined by flow cytometry using counting beads as a reference. Labelling with Annexin-V was used to detect the total microparticle fraction. EMPs were characterized as CD31+CD42- and PMPs as CD31+CD42+. HR increased after electronic cigarettes use and tobacco smoking (P < 0.001), whereas blood pressure remained unchanged (P > 0.05). RHI (P = 0.006), augmentation index (P = 0.010) but not augmentation index standardized to HR 75 bpm (P > 0.05) increased with electronic cigarettes use but not with tobacco smoking. Following tobacco smoking, there was a significant increase in total microparticles (P < 0.001), EMPs (P < 0.001) and PMPs (P < 0.001). In contrast, electronic cigarettes were only associated with an increase in PMPs (P < 0.001), with no significant changes in the total microparticle fraction or EMPs (all P > 0.05). Peak expiratory flow significantly decreased following electronic cigarettes use (P = 0.019). Our results demonstrate that acute exposure to tobacco smoking as well as electronic cigarettes influences vascular and respiratory function. Where tobacco smoking significantly increased microparticle formation, indicative of possible endothelial injury, electronic cigarettes use induced vasoreactivity and decreased peak expiratory flow. These findings suggest that both electronic cigarettes and tobacco smoking negatively impact vascular function.

Intramuscular versus oral corticosteroids to reduce relapses following discharge from the emergency department for acute asthma.

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To examine the effectiveness and safety of intramuscular (IM) versus oral corticosteroids in the treatment of acute asthma after discharge from a hospital emergency department (ED) or equivalent acute care setting.

Association of short‐term ozone exposure with pulmonary function and respiratory symptoms in schoolchildren:A panel study in a western Japanese city

The average annual ozone levels have been increasing in Japan, even though the high ozone levels have decreased in recent years. There is limited information on the relationship between ozone exposure, pulmonary function, and respiratory symptoms in schoolchildren in Japan. The aim of this study was to investigate the effects of short-term ozone exposure on pulmonary function and respiratory symptoms in Japanese schoolchildren. Afternoon peak expiratory flow (PEF) values and respiratory symptom scores were recorded daily in 276 schoolchildren from September to October 2016 and from January to February 2017. The association of daily ozone levels with PEF was assessed using a linear mixed model and that with respiratory symptoms was evaluated by generalized estimating equations logistic regression analysis. There was a significant association of daily ozone levels with PEF values. A 13.6-ppb increment in the interquartile range for ozone exposure was significantly associated with a decrease in PEF of -3.67 L/min (95% confidence interval -4.73, -2.61). However, increased ozone levels were not associated with an increased risk of respiratory symptoms. Our present findings suggest that more attention should be paid to the potential adverse effects of short-term ozone exposure on pulmonary function in schoolchildren. J. Med. Invest. 65:236-241, August, 2018.

The Effect of Deep Versus Moderate Neuromuscular Block on Surgical Conditions and Postoperative Respiratory Function in Bariatric Laparoscopic Surgery: A Randomized, Double Blind Clinical Trial

In recent literature, it has been suggested that deep neuromuscular block (NMB) improves surgical conditions during laparoscopy; however, the evidence supporting this statement is limited, and this was not investigated in laparoscopic bariatric surgery. Moreover, residual NMB could impair postoperative respiratory function. We tested the hypotheses that deep NMB could improve the quality of surgical conditions for laparoscopic bariatric surgery compared with moderate NMB and investigated whether deep NMB puts patients at risk for postoperative respiratory impairment compared with moderate NMB. Sixty patients were evenly randomized over a deep NMB group (rocuronium bolus and infusion maintaining a posttetanic count of 1-2) and a moderate NMB group (rocuronium bolus and top-ups maintaining a train-of-four count of 1-2). Anesthesia was induced and maintained with propofol and remifentanil. The primary outcome measures were the quality of surgical conditions assessed by a single surgeon using a 5-point rating scale (1 = extremely poor, 5 = optimal), the number of intra-abdominal pressure increases >18 cmH2O and the duration of surgery. Secondary outcome measure was the postoperative pulmonary function assessed by peak expiratory flow, forced expiratory volume in 1 second, and forced vital capacity, and by the need for postoperative respiratory support. Data are presented as mean ± standard deviation with estimated treatment effect (ETE: mean difference [95% confidence interval]) for group comparisons. There was no statistically significant difference in the surgeon's rating regarding the quality of the surgical field between the deep and moderate NMB group (4.2 ± 1.0 vs 3.9 ± 1.1; P = .16, respectively; ETE: 0.4 [-0.1, 0.9]). There was no difference in the proportional rating of surgical conditions over the 5-point rating scale between both groups (P = .91). The number of intra-abdominal pressure increases >18 cmH2O and the duration of surgery were not statistically different between the deep and moderate NMB group (0.2 ± 0.9 vs 0.3 ± 1.0; P = .69; ETE: -0.1 [-0.5, 0.4] and 61.3 ± 15.1 minutes vs 70.6 ± 20.8 minutes; P = .07, ETE: -9.3 [-18.8, 0.1], respectively). All the pulmonary function tests were considerably impaired in both groups when compared with baseline (P < .001). There was no statistically significant difference in the decrease in peak expiratory flow, forced expiratory volume in 1 second, and forced vital capacity (expressed as % change from baseline) between the deep and the moderate NMB group. Compared with a moderate NMB, there was insufficient evidence to conclude that deep NMB improves surgical conditions during laparoscopic bariatric surgery. Postoperative pulmonary function was substantially decreased after laparoscopic bariatric surgery independently of the NMB regime that was used. The study is limited by a small sample size.

Acute effects of air pollutants on pulmonary function among students: a panel study in an isolated island

BackgroundMany epidemiological studies on the health effects of air pollutants have been carried out in regions with major sources such as factories and automobiles. However, the health effects of air pollutants in regions without major sources remain unclear. This study investigated the acute effects of ambient air pollution on pulmonary function among healthy students in an isolated island without major artificial sources of air pollutants.MethodsA panel study was conducted of 43 healthy subjects who attended a school in an isolated island in the Seto Inland Sea, Japan. We measured the forced expiratory volume in 1 s (FEV1) and peak expiratory flow (PEF) every morning for about 1 month in May 2014. Ambient concentrations of particulate matter ≤ 2.5 μm in diameter (PM2.5), particulate matter between 2.5 and 10 μm in diameter (PM10-2.5), black carbon (BC), ozone (O3), and nitrogen dioxide (NO2) were measured. The associations between the concentrations of air pollutants and pulmonary function were analyzed using mixed-effects models.ResultsA decrease in FEV1 was significantly associated with BC concentrations (−27.28 mL [95%confidence interval (CI):−54.10,−0.46] for an interquartile range (IQR) increase of 0.23 μg/m3). The decrease in PEF was significantly associated with indoor O3 concentrations (−8.03 L/min [95% CI:−13.02,−3.03] for an IQR increase of 11 ppb). Among subjects with a history of allergy, an increase in PM2.5 concentrations was significantly associated with low FEV1. In subjects with a history of asthma, an inverse association between the indoor O3 concentration and pulmonary function was observed.ConclusionsOur results demonstrate that increases in BC and O3 concentrations have acute effects on the pulmonary function among students in an isolated island without major artificial sources of air pollutants.

Decreased Peak Expiratory Flow Associated with Muscle Fiber-Type Switching in Spinal and Bulbar Muscular Atrophy.

The aim of this study was to characterize the respiratory function profile of subjects with spinal and bulbar muscular atrophy (SBMA), and to explore the underlying pathological mechanism by comparing the clinical and biochemical indices of this disease with those of amyotrophic lateral sclerosis (ALS). We enrolled male subjects with SBMA (n = 40) and ALS (n = 25) along with 15 healthy control subjects, and assessed their respiratory function, motor function, and muscle strength. Predicted values of peak expiratory flow (%PEF) and forced vital capacity were decreased in subjects with SBMA compared with controls. In SBMA, both values were strongly correlated with the trunk subscores of the motor function tests and showed deterioration relative to disease duration. Compared with activities of daily living (ADL)-matched ALS subjects, %PEF, tongue pressure, and grip power were substantially decreased in subjects with SBMA. Both immunofluorescence and RT-PCR demonstrated a selective decrease in the expression levels of the genes encoding the myosin heavy chains specific to fast-twitch fibers in SBMA subjects. The mRNA levels of peroxisome proliferator-activated receptor gamma coactivator 1-alpha and peroxisome proliferator-activated receptor delta were up-regulated in SBMA compared with ALS and controls. In conclusion, %PEF is a disease-specific respiratory marker for the severity and progression of SBMA. Explosive muscle strength, including %PEF, was selectively affected in subjects with SBMA and was associated with activation of the mitochondrial biogenesis-related molecular pathway in skeletal muscles.

Safety and tolerability of once-daily tiotropium Respimat® as add-on to at least inhaled corticosteroids in adult patients with symptomatic asthma: A pooled safety analysis

BackgroundTiotropium, a long-acting anticholinergic bronchodilator, has demonstrated efficacy and safety as add-on therapy to inhaled corticosteroids (ICS), with or without other maintenance therapies, in patients with symptomatic asthma. ObjectiveTo evaluate safety and tolerability of tiotropium delivered via the Respimat® device, compared with placebo, each as add-on to at least ICS therapy, in a pooled sample of adults with symptomatic asthma at different treatment steps. MethodsData were pooled from seven Phase II and III, randomised, double-blind, parallel-group trials of 12–52 weeks’ treatment duration, which investigated once-daily tiotropium Respimat® (5 μg, 2.5 μg) versus placebo as add-on to different background maintenance therapy including at least ICS. Adverse events (AEs) including serious AEs were assessed throughout treatment + 30 days after the last dose of trial medication. ResultsOf 3474 patients analysed, 2157 received tiotropium. The percentage of patients with AEs was comparable between treatment groups: tiotropium 5 μg, 60.8%; placebo 5 μg pool, 62.5%; tiotropium 2.5 μg, 57.1%; placebo 2.5 μg pool, 55.1%. Consistent with the disease profile, the most frequent AEs overall were asthma, decreased peak expiratory flow rate (both less frequent with tiotropium) and nasopharyngitis. Overall incidence of dry mouth, commonly associated with use of anticholinergics, was low: tiotropium 5 μg, 1.0%; placebo 5 μg pool, 0.5%; tiotropium 2.5 μg, 0.4%; placebo 2.5 μg pool, 0.5%. The percentage of cardiac disorder AEs was comparable between tiotropium and placebo: tiotropium 5 μg, 1.4%; placebo 5 μg pool, 1.4%; tiotropium 2.5 μg, 1.4%; placebo 2.5 μg pool, 1.1%. The proportions of patients with serious AEs were balanced across groups: tiotropium 5 μg, 4.0%; placebo 5 μg pool, 4.9%; tiotropium 2.5 μg, 2.0%; placebo 2.5 μg pool, 3.3%. ConclusionTiotropium Respimat® demonstrated safety and tolerability comparable with those of placebo, as add-on to at least ICS therapy, at different treatment steps in adults with symptomatic asthma.

A panel study of airborne particulate matter composition versus concentration: Potential for inflammatory response and impaired pulmonary function in children

BackgroundThe relationship between airborne particulate matter (PM) and pulmonary function in children has not been consistent among studies, potentially owing to differences in the inflammatory response to PM, based on PM types and sources. The objective of this study was to investigate the effect of airborne PM on pulmonary function in schoolchildren and its potential for an inflammatory response. MethodsDaily morning peak expiratory flow (PEF) was measured in 339 schoolchildren in February 2015. Interleukin (IL)-8 production was assessed in THP1 cells stimulated by airborne PM collected every day during the study period, and these IL-8 concentrations are described as the daily IL-8 levels. A linear mixed model was used to estimate the association between PEF values and the daily levels of suspended PM (SPM), PM diameters smaller than 2.5 μm (PM2.5), and IL-8. ResultsThe daily IL-8 levels were significantly associated with those of SPM and PM2.5. A 0.83 μg/mL increase in IL-8 levels was significantly associated with a −1.07 L/min (95% confidence interval, −2.05 to −0.08) decrease in PEF. A 12.0 μg/m3 increase in SPM and a 10.0 μg/m3 increase in PM2.5 were associated with a −1.36 L/min (−2.93 to 0.22) and −1.72 L/min (−3.82 to 0.36) decreases in PEF, respectively. There were no significant relationships between PEF, SPM, and PM2.5. ConclusionsThese findings suggest that the effects of airborne PM on pulmonary function in schoolchildren might depend more on the pro-inflammatory response than the mass concentration of the PM.

Association between pulmonary function and daily levels of sand dust particles assessed by light detection and ranging in schoolchildren in western Japan: A panel study

BackgroundAn important aspect of sand dust emissions in association with respiratory disorders is the quantity of particulate matter. This is usually expressed as particulate matter less than 10 μm (PM10) and 2.5 μm (PM2.5). However, the composition of PM10 and PM2.5 varies. Light detection and ranging is used to monitor sand dust particles originating in East Asian deserts and distinguish them from air pollution aerosols. The objective of this study was to investigate the association between the daily levels of sand dust particles and pulmonary function in schoolchildren in western Japan. MethodsIn this panel study, the peak expiratory flow (PEF) of 399 schoolchildren was measured daily from April to May 2012. A linear mixed model was used to estimate the association of PEF with the daily levels of sand dust particles, suspended particulate matter (SPM), and PM2.5. ResultsThere was no association between the daily level of sand dust particles and air pollution aerosols, while both sand dust particles and air pollution aerosols had a significant association with SPM and PM2.5. An increment of 0.018 km−1 in sand dust particles was significantly associated with a decrease in PEF (−3.62 L/min; 95% confidence interval, −4.66 to −2.59). An increase of 14.0 μg/m3 in SPM and 10.7 μg/m3 in PM2.5 led to a significant decrease of −2.16 L/min (−2.88 to −1.43) and −2.58 L/min (−3.59 to −1.57), respectively, in PEF. ConclusionsThese results suggest that exposure to sand dust emission may relate to pulmonary dysfunction in children in East Asia.

Change in peak expiratory flow over time among workers exposed to polyvinyl chloride dust.

To evaluate the variation of peak expiratory flow (PEF) over a working week among non-smoking workers without previous asthma who have been exposed to polyvinyl chloride (PVC) dust. We conducted a cross-sectional study among 42 operators with exposure to PVC dust (filling hoppers to feed extrusion machines) and 23 employees without exposure to PVC dust in a plant producing PVC pipes in West Africa. A pre-tested questionnaire was administered and PEF was measured using a portable peak flow meter after a day off (day 1), on day 3 and at the end of the week (day 6). The two groups did not differ by age or body mass index. Dyspnoea was more prevalent in exposed workers than controls (52% vs. 13%, P = 0.002). PEF decreased more significantly in exposed workers than controls (-8% vs. -3% on day 3 and -10% vs. -5% on day 6, both P = 0.004). The duration of exposure did not affect PEF variability in the exposed groups. The decrease of PEF over the working week in workers exposed to PVC dust is consistent with occupational asthma, although standard measures to diagnose occupational asthma were not used. This result reinforces the need to prevent excessive exposure to PVC dust.