Comparative study of seasonal variability in peak expiratory flow rate amongst school children in rural and urban areas

Background: Peak Expiratory Flow (PEF) is a value test for lung function and can be conveniently measured by using relatively inexpensive and portable Peak Flow Meter, identifying and assessing the degree of airflow limitation of individuals. While PEFR is obviously related to factors like age, weight, height, race, gender, it may also be additionally affected by seasons and climate. The purpose of study being to observe seasonal variation in PEFR amongst school going children and to observe peak expiratory flow rate in school going children in urban and rural areas.Methods: This prospective and comparative study was carried out on total 600 children; with 300 each from rural and urban schools, of age group 10-14 years, both sexes. Peak expiratory flow meter was used for the measurements in the seasons of summer (April to June) and winter (December to February) of the year. The results thus obtained were compiled and analysed.Results: The mean PEFR value (Litres/min) during summers in the rural children was 243.50(S.D.=16.050) while during winters was 253.63(S.D.=16.934), highly significant (p<0.001); mean PEFR summers in the urban children was 241.50(S.D.=20.530)and during winters was 249.93(S.D.=21.685), again highly significant (p<0.001).In both rural and urban groups PEFR values increased with increase in height and weight of the children which was found to be highly significant (p<0.001). Girls representation proportion in rural vs urban schools being 49% vs 45%; whereas boys being 51% vs 55% respectively.Conclusions: Peak expiratory flow rate decreased during summer season of the year in both rural and urban school attending children. In both the groups PEFR values had a direct correlation with height and weight of the children. Rural schools showed more girl student representation than their urban counterparts indicating more awareness for girl child education amongst rural population.

Assessing Airflow Limitation among Smokers in a Primary Care Setting

Background: Many smokers have undiagnosed chronic obstructive pulmonary disease(COPD), and yet screening for COPD is not recommended. Smokers who know that they haveairflow limitation are more likely to quit smoking. This study aims to identify the prevalence andpredictors of airflow limitation among smokers in primary care.Methods: Current smokers ≥ 40 years old who were asymptomatic clinic attendees in aprimary care setting were recruited consecutively for two months. We used a two-step strategy.Step 1: participants filled in a questionnaire. Step 2: Assessment of airflow limitation using apocket spirometer. Multiple logistic regression was utilised to determine the best risk predictorsfor airflow limitation.Results: Three hundred participants were recruited. Mean age was 58.35 (SD 10.30) yearsold and mean smoking history was 34.56 pack-years (SD 25.23). One in two smokers were found tohave airflow limitation; the predictors were Indian ethnicity, prolonged smoking pack-year historyand Lung Function Questionnaire score ≤ 18. Readiness to quit smoking and the awareness ofCOPD were low.Conclusions: The high prevalence of airflow limitation and low readiness to quit smokingimply urgency with helping smokers to quit smoking. Identifying airflow limitation as an additionalmotivator for smoking cessation intervention may be considered. A two-step case-finding methodis potentially feasible.

The impact of different doses of azithromycin maintenance treatment on expiratory flow limitation and quality of life among stable patients with non-cystic fibrosis bronchiectasis / 中国医师进修杂志

Objective To observe the benefits and safety of different maintenance doses of azithromycin for long-term treatment in adult patients with non-cystic fibrosis (CF) bronchiectasis. Methods One hundred and thirty-two indigenous outpatients (>18 years old) with stable non-CF bronchiectasis were enrolled. All patients were randomly assigned to a control group and two treatment groups. Patients in the azithromycin fixed-dose treatment group received oral azithromycin (250 mg daily) and ambroxol hydrochloride (30 mg, 3 times/d). Azithromycin progressively decreased dosage treatment group received oral azithromycin (250 mg daily for 8 weeks-250 mg 3 times/week for 8 weeks-250 mg 2 times/week for 10 weeks) and ambroxol hydrochloride (30 mg, 3 times/d). Subjects in control group only received ambroxol hydrochloride therapy. The course of treatment lasted for 26 weeks. Spirometry, exacerbations, sputum microbiology, quality of life, dyspnea scores and adverse effects were monitored after treatment for 26 weeks. Results One hundred and twenty-nine evaluable subjects completed the study. After treatment, the level of percentage of estimated value forced expiratory volume in 1 second (FEV1% Pred) in azithromycin fixed-dose treatment group and azithromycin progressively decreased dosage treatment group was significantly higher than that before treatment: (83.01 ± 5.79)% vs. (79.39 ± 3.53)%, (84.97 ± 5.10)% vs. (80.94 ± 3.46)%, P<0.05. Forced expiratory flow between 25% and 75% of vital capacity (FEF25%- 75%) was also increased in two groups: (54.87 ± 5.72) % vs. (51.86 ± 8.16)%, (55.65 ± 3.39)% vs. (53.46 ± 5.75)% , there was significant difference (P<0.05). But the levels of above parameters between two groups after treatment had no significant differences (P >0.05). The parameters of FEV1% Pred, forced expiratory volume in 1 second (FEV1)/forced ventilatory capacity (FVC) and FEF25%-75%were lower compared to those before treatment in the control group (P <0.05). However, the scores of LRTI-VAS and FACED in control group after treatment were decreased slightly: (20.55 ± 1.76) scores vs. (21.34 ± 1.86) scores, P<0.05; (4.16 ± 0.75) scores vs. (4.36 ± 0.72) scores, P > 0.05. Seven episodes of acute exacerbation was occured during 26 weeks, 2 cases exited. The others did not interrupt azithromycin treatment during acute exacerbation. Drug-related adverse reactions were mild. Conclusions For adult stable patients with non-CF bronchiectasis, the clinical symptoms and airflow limitation are improved after long-term treatment of low-dose azithromycin. Similar effects on FACED score and LRTI-VAS score are observed in patients with progressively decreased dosage of azithomycin.

The pathological changes of visceral pleura in patients with chronic obstructive pulmonary disease / 天津医药

Objective To observe the pathological change of visceral pleura in patients with chronic obstructive pulmonary disease (COPD), and to discuss the relationship between the changes and COPD airflow limitation. Methods A total of 70 patients received the pulmonary lobectomy or partial resection because of lung tumor in Tianjin Chest Hospital from May 2014 to August 2015 were selected in this study. According to the results of pulmonary function test, the patients were divided into COPD group [forced expiratory volume in one second (FEV1)/ forced vital capacity (FVC) 0.05). The visceral pleural thickness and the proportion of elastic fibers in visceral pleural were significantly thinner in COPD group than those of control group ( P0.05). Conclusion The thinner visceral pleural and the reduction of elastic fibers in visceral pleural are one of the causes of expiratory airflow limitation in COPD patients.

Influential factors of airflow limitation in patients with chronic obstructive pulmonary disease:an analysis using quantitative CT / 实用放射学杂志

Objective To evaluate the correlations of emphysema and airway wall thickness to chronic obstructive pulmonary disease(COPD) of airflow limitation by quantitative CT.Methods 40 COPD patients and other 40 normal controls underwent pulmonary function tests and following MSCT exams with inspiration.The square root of wall area of an airway with an internal area of 8 mm2 (Ai8) and the percentage of low attenuation volume(LAV%) of the whole lung and each lobes at the threshold of-950 HU were measured by a software of Thoracic VCAR.The Ai8 between the observation group and the control one was compared using SPSS2.2.The contributions of LAV% and Ai8 to predictions of FEV1/FVC and FEV1% were also evaluated.Results There was a significantly statistical difference in the Ai8 between the observation group and the control one.There were correlations between airflow limitation markers and all of LAV% as well as Ai8 (P<0.05 for all standardized coefficients).Only the Ai8 of right inferior lobar made a significant contribution to airflow limitation in the whole lung bronchus, and the LAV% of each lobes made a stronger contribution to airflow limitation than the Ai8 of right inferior lobe.Conclusion There is a significantly statistical difference in the Ai8 between the observation group and the control one.The LAV% may make a greater contribution to airflow limitation than Ai8 in COPD group.The influential factors of airflow limitation in order were LAV%, Ai8 of right inferior lobe and Ai8 of the other lobes.

Pale nasal mucosa affects airflow limitations in upper and lower airways in asthmatic children

BACKGROUND: Severe asthmatics are thought to have severer rhinitis than mild asthmatics. A pale nasal mucosa is a typical clinical finding in subjects with severe allergic rhinitis. OBJECTIVE: The aim of this study was to investigate whether a pale nasal mucosa affects airflow limitations in the upper and lower airways in asthmatic children. METHODS: Rhinomanometry, nasal scraping, and spirometry were performed in 54 asthmatic children (median age, 10 years). The nasal mucosa was evaluated by an otolaryngologist. Thirty-seven patients were treated with inhaled corticosteroids, and 11 patients were treated with intranasal corticosteroids. RESULTS: Subjects with a pale nasal mucosa (n = 23) exhibited a lower nasal airflow (p < 0.05) and a larger number of nasal eosinophils (p < 0.05) in the upper airway as well as lower pulmonary functional parameters (p < 0.05 for all comparisons), i.e., the forced vital capacity (FVC), the forced expiratory volume in 1 second, and the peak expiratory flow, compared with the subjects who exhibited a normal or pinkish mucosa (n = 31). No significant difference in the forced expiratory flow between 25%–75% of the FVC, regarded as indicating the peripheral airway, was observed between the 2 groups. CONCLUSION: A pale nasal mucosa may be a predictor of eosinophil infiltration of the nasal mucosa and central airway limitations in asthmatic children. When allergists observe a pale nasal mucosa in asthmatic children, they should consider the possibility of airflow limitations in not only the upper airway, but also the lower airway.

Effect of Airflow Limitation on Acute Exacerbations in Patients with Destroyed Lungs by Tuberculosis

History of treatment for tuberculosis (TB) is a risk factor for obstructive lung disease. However, it has been unclear whether the clinical characteristics of patients with destroyed lung by TB differ according to the presence or absence of airflow limitation. The objective of the study was to evaluate differences in acute exacerbations and forced expiratory volume in 1 second (FEV1) decline in patients with destroyed lung by TB according to the presence or absence of airflow limitation. We performed a retrospective cohort study and enrolled patients with destroyed lung by TB. The presence of airflow limitation was defined as FEV1/forced vital capacity (FVC) < 0.7. One hundred and fifty-nine patients were enrolled, and 128 (80.5%) had airflow limitation. The proportion of patients who experienced acute exacerbation was higher in patients with airflow limitation compared to those without (89.1 vs. 67.7%, respectively; P = 0.009). The rate of acute exacerbation was higher in patients with airflow limitation (IRR, 1.19; 95% CI, 1.11-1.27). Low body mass index (X vs. X + 1; HR, 0.944; 95% CI, 0.895-0.996) in addition to airflow limitation (HR, 1.634; 95% CI, 1.012-2.638), was an independent risk factor for acute exacerbation. The annual decline of FEV1 was 2 mL in patients with airflow limitation and 36 mL in those without (P < 0.001). In conclusion, the presence of airflow limitation is an independent risk factor for acute exacerbation in patients with the destroyed lung by TB.

Chronic obstructive pulmonary disease.

The global prevalence of physiologically defined chronic obstructive pulmonary disease (COPD) in adults aged >40 yr is approximately 9-10 per cent. Recently, the Indian Study on Epidemiology of Asthma, Respiratory Symptoms and Chronic Bronchitis in Adults had shown that the overall prevalence of chronic bronchitis in adults >35 yr is 3.49 per cent. The development of COPD is multifactorial and the risk factors of COPD include genetic and environmental factors. Pathological changes in COPD are observed in central airways, small airways and alveolar space. The proposed pathogenesis of COPD includes proteinase-antiproteinase hypothesis, immunological mechanisms, oxidant-antioxidant balance, systemic inflammation, apoptosis and ineffective repair. Airflow limitation in COPD is defined as a postbronchodilator FEV1 (forced expiratory volume in 1 sec) to FVC (forced vital capacity) ratio <0.70. COPD is characterized by an accelerated decline in FEV1. Co morbidities associated with COPD are cardiovascular disorders (coronary artery disease and chronic heart failure), hypertension, metabolic diseases (diabetes mellitus, metabolic syndrome and obesity), bone disease (osteoporosis and osteopenia), stroke, lung cancer, cachexia, skeletal muscle weakness, anaemia, depression and cognitive decline. The assessment of COPD is required to determine the severity of the disease, its impact on the health status and the risk of future events (e.g., exacerbations, hospital admissions or death) and this is essential to guide therapy. COPD is treated with inhaled bronchodilators, inhaled corticosteroids, oral theophylline and oral phosphodiesterase-4 inhibitor. Non pharmacological treatment of COPD includes smoking cessation, pulmonary rehabilitation and nutritional support. Lung volume reduction surgery and lung transplantation are advised in selected severe patients. Global strategy for the diagnosis, management and prevention of Chronic Obstructive Pulmonary Disease guidelines recommend influenza and pneumococcal vaccinations.

Analysis of bronchial dilation test and bronchial provocation test for 650 cases of asthma patients / 重庆医学

Objective To analyse the airway reversibility and variability for bronchial asthmatic patients .Methods The status of test positive ratio and combined airflow limitation were analysis for 650 Clinical diagnosed asthmatic patients .527 cases were given bronchial dilation test and 123 cases were given provocative test .Results Positive ratio of 527 cases bronchial dilation test was 41 . 4% .Positive ratio of 123 cases provocative test was 52 .0% .The airflow limitation(FEV1/FVC% <70% ) ratio of total 650 cases was 34 .0% .In the 193 cases of combined airflow limitation patients which was given bronchial dilation test ,the positive ratio of bronchial dilation test was 61 .7% .Conclusion Bronchial dilation test need repeat because of its less sensitivity .The positive ratio of provocative test is not high ,so the patients of provocative test negative couldn′t exclude the diagnosis of asthma .The ratio of bronchial dilation test was high for combined airflow limitation asthmatic patients .Its may clew that the patients combined airflow limitation may be exacerbation and need actively therapy .

Global strategy for diagnosis, management and prevention of chronic obstructive pulmonary disease / Монголын Анагаах Ухаан

Introduction:Chronic Obstructive Pulmonary Disease (COPD) is a preventable and treatable disease characterized by airflow limitation that is not fully reversible. The prevalence and burden Of COPD are projected to increase in the coming decades due to continued exposure to COPD risk factors and the changing age structure of the world’s population. COPD is one of the most important causes of death in most countries. The Global Burden of Disease Study has projected that COPD, which ranked sixth as the cause of death in 2000, will become the third leading cause of death worldwide by 2020. The chronic airflow limitation characteristic of COPD is caused by a mixture of small airway disease (obstructive bronchiolitis) and parenchymal destruction (emphysema). Airflow limitation is best measured by spirometry, as this the most widely available, reproducible test of lung function. COPD itself also has significant extrapulmonary (systemic) effects that lead to comorbid conditions. The goals of treatment of patients with stable chronic obstructive pulmonary disease (COPD) include: maintaining optimal health, symptom relief, preventing progression of disease, increase exercise tolerance, preventing complications and exacerbations, improving control of symptoms, enabling the patient to function to the greatest extent possible, improving quality of life. Home treatment usually works well for most people, but others with very severe disease may need hospitalisation. With early diagnosis, lifestyle changes (e.g., smoking cessation), and appropriate treatment, many people can lead normal and productive lives.

Symptom Questionnaire and Laboratory Findings in Subjects with Airflow Limitation: a Nation-wide Survey / 결핵및호흡기질환

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation that is not fully reversible. COPD has systemic effects, such as skeletal muscle dysfunction and abnormal weight loss. It also has been suggested that COPD is related to other chronic disease, such as cardiovascular disease, osteoporosis, and anemia. The aim of this study was to evaluate a symptom questionnaire and laboratory findings in subjects with air flow limitation. METHODS: We evaluated a symptom questionnaire and laboratory findings in subjects with airflow limitation detected by spirometry in conjunction with the Second Korean National Health and Nutrition Examination Survey. A total of 9,243 adults over the age of 18 were recruited. Among the adults, we finally analyzed 2,217 subjects who met the acceptability and repeatability criteria of spirometry, showed normal findings on chest radiography, and were older than 40 years of age. RESULTS: There were 288 subjects with airflow limitation as determined by spirometry. The frequency of respiratory symptoms such as cough, sputum and wheezing were significantly higher in subjects with airflow limitation (p<0.01). Hemoglobin and hematocrit levels were higher in subjects with airflow limitation (hemoglobin level 13.98 mg/dL vs. 13.62 mg/dL, hematocrit 42.10% vs. 40.89%; p<0.01). The HDL cholesterol level was lower in subjects with airflow limitation (44.95 mg/dL vs. 45.60 mg/dL; p<0.01). There was no significant difference in the total cholesterol, triglyceride, blood urea nitrogen, creatinine, and fasting glucose levels. CONCLUSION: In subjects with airflow limitation, prevalence of respiratory symptoms was higher than in normal spirometry subjects and the levels of hemoglobin and the hematocrit were higher. The HDL cholesterol level was lower in subjects with airflow limitation.

Pathophysiology of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a chronic progressive disease that is characterized by irreversible airflow limitation with a partially reversible component. The pathologic abnormalities of COPD are associated with lung inflammation, an imbalance of proteinases and antiproteinases, and oxidative stress that are induced by noxious particles and gases in susceptible individuals. The physiologic changes of COPD are mucus hypersecretion, ciliary dysfunction, airflow limitation, pulmonary hyperinflation, gas exchange abnormalities, pulmonary hypertension, cor pulmonale, and systemic effects. The airflow limitation results principally from an increase in the resistance of the small conducting airways and a decrease in the pulmonary elastic recoil due to emphysematous lung destruction. This article provides a general overview of the pathophysiology of COPD.

Pathophysiology of Chronic Obstructive Pulmonary Disease / 결핵및호흡기질환

Chronic obstructive pulmonary disease (COPD) is a chronic progressive disease, characterized by irreversible airflow limitation, with a partially reversible component. The pathological abnormalities of COPD are associated with lung inflammation, imbalances of proteinase and antiproteinase, and oxidative stress, which are induced by noxious particles and gases in susceptible individuals. The physiological changes of COPD are mucus hyper-secretion, ciliary dysfunction, airflow limitation, pulmonary hyperinflation, gas exchange abnormalities, pulmonary hypertension, cor pulmonale and systemic effects. The airflow limitation principally results from an increase in the resistance of the small conducting airways and a decrease in pulmonary elastic recoil due to emphysematous lung destruction. This article provides a general overview of the pathophysiology of COPD.

Change of Lung Volumes in Chronic Obstructive Pulmonary Disease Patients with Improvement of Airflow Limitation after Treatment / 결핵및호흡기질환

BACKGROUND: It is important to predict the exercise capacity and dyspnea, as measurements of lung volume, in patients with COPD. However, lung volume changes in response to an improvement in airflow limitation have not been explored in detail. In the present study, it is hypothesized that lung volume responses might not be accurately predicted by flow responses in patients with moderate to severe airflow limitations. METHODS: To evaluate lung volume responses, baseline and follow up, flow and lung volumes were measured in moderate to severe COPD patients. The flow response was defined by an improvement in the FEV1 of more than 12.3%; lung volume changes were analyzed in 17 patients for the flow response. RESULTS: The mean age of the subjects was 66 years; 76% were men. The mean baseline FEV1, FEV1/FVC and RV were 0.98L (44.2% predicted), 47.5% and 4.65 L (241.5%), respectively. The mean follow up duration was 80 days. The mean differences in the FEV1, FVC, TLC and RV were 0.27 L, 0.39 L, -0.69 L and -1.04 L, respectively, during the follow up periods. There was no correlation between the delta FEV1 and delta RV values(r=0.072, p=0.738). CONCLUSION: To appropriately evaluate the lung function in patients with moderate to severe airflow limitations; serial lung volume measurements would be helpful.