Pulmonary function studies in healthy school boys of West Bengal.

The establishment of normal standards of dynamic pulmonary function measurements in the form of prediction equations will serve as a remedial measure of different aspects of obstructive pulmonary diseases, especially in children. With a view to achieving the target, dynamic pulmonary function measurements were undertaken on 328 healthy school-going children of West Bengal having age ranging between 9 and 18 years. All the spirometric measurements except PEFR were taken with the help of a 9 l closed-circuit type expirograph following the methods and techniques of American Thoracic Society. PEFR was measured by Wright Peak Flow Meter. Prediction equations were derived on the basis of age and height for all the pulmonary function measurements except FEV1% and FET. The prediction equations for FVC, FEV1, MVVF, and PEFR were reliable, but relative variability of predicted FEF25-75% and FEF75-85% was very large. A comparative study of FVC, FEV1, and PEFR values of our subjects, standardized for age and height, was much closer to the boys of Delhi in FVC but higher than South Indian boys in FEV1, North and South Indian boys in PEFR. In an attempt to compare FVC and FEV1 values of our subjects with foreign populations, it is revealed that boys of our study were much lower than American (White), European, and Jordanian boys but comparable with those of Chinese and Libyan boys.     

Pulmonary function studies in healthy non-smoking men of Calcutta

Pulmonary function measurements were made in 104 healthy non-smoking men from Calcutta with an age range of 20-59 years. Except for peak expiratory flow rate (PEFR), all the measurements were made with the help of two 9L closed-circuit type expirographs using standard spirometric techniques. PEFR was recorded by two Wright peak flow meters. Prediction formulae were derived on the basis of age and height for all the ventilatory tests except for FEV1%, FET and PEFR. These were predicted from age only. The prediction equation for VC, FVC, FEV1, FEV1%, MVVF and PEFR were reliable, but those for forced expitatory flows and time were not. The FVC and FEV1 values of the present subjects, standardized for age and height, were much lower than those of Americans, Caucasians, Europeans and Canadians but similar to those of Pakistani healthy adults. On comparison with the data reported from other parts of our country, it was revealed that the VC and FEV1 values of the current study, after adjustment of age and height, were much higher than those of southern Indians but comparable with those of north-western Indians.     

Spirometric reference values from a Mediterranean population

Maximal expiratory flow-volume (MEFV) curves were measured in 1044 healthy nonsmoking volunteers living in the Barcelona area, as part of a larger interhospital project to obtain reference values of pulmonary function tests. Forced vital capacity (FVC), one-second forced expiratory volume (FEV1), FEV1/FVC, %, forced maximal mid-expiratory flow (FEF25-75%), peak expiratory flow rate (PEF) and maximal expiratory flow at 50 and 75% of FVC (MEF50% and MEF25% respectively) were obtained and expressed at BTPS conditions. Techniques and equipments followed both the recommendations of the American Thoracic Society (ATS) and of the European Community for Coal and Steel (ECCS). Prediction equations for age 20 through 70 were calculated for both sexes from a final sample composed of 870 adult subjects, 443 males and 427 females. Simple linear equations using height, age and body weight predicted all spirometric variables as well as more complex equations except MEF25%. Logarithmic equations were proposed for MEF25% to correct for the heteroscedasticity shown in a simple linear model. To our knowledge, this study provides reliable spirometric equations from a large urban Mediterranean sample which were lacking so far in the literature.     

Pulmonary function in normal Japanese children 6 to 16 years of age

We measured pulmonary function on 182 healthy Japanese children 6 to 16 years of age living in the Tokyo area. Static lung volumes, RV/TLC (%), FRC/TLC (%), FVC, FEV1, FEV1/FVC (%), MMFR, MVV, f, VE and VO2 were measured. Multiple regression equations were obtained and the results were compared with those derived from the other equations (Kanagami (1958), Ishida (1955]. The predicted values were about 10 approximately 25% higher with our equations than those obtained from the other equations which were made more than 30 years ago. These differences were attributed to the recent improvement in growth of the Japanese children. For this reason we think it is better now to adopt new equations for the prediction of normal values in Japanese children.     

Spirometric standards for healthy children and adolescents of Korean Chinese in northeast China

In China there are 1,923,842 Korean Chinese, who live mostly (92.27%) in the country's three northeast provinces. In spite of this sizeable number, no spirometric data are available at present on them. The present study investigated normal spirometric reference values for the Korean Chinese children and adolescents. Spirometry was performed in 443 healthy Korean Chinese children and adolescents aged 8-18 yr with measurements of forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), peak expiratory flow (PEF) and maximum mid-expiratory flow (MMEF). Reference equations for FEV1, FVC, PEF and MMEF were derived by using multiple regression analysis. All of the measured spirometric parameters correlated positively with height and age significantly (P < 0.001). The predicted values of FVC and FEV1 were higher than values obtained by using Caucasian and other Asian equations (P < 0.001). A set of spirometric reference equations has been derived using a relatively large, healthy, non-smoking young Korean Chinese population with a wide range of ages and heights, the results of which differ from those gained from several other reference equations. These reference equations should be used for evaluation of lung function in this population.     

Spirometric reference values for children and adolescents from Kazakhstan

BACKGROUND: Spirometric parameters are influenced by several factors and many reference data are available in the literature. However, no spirometric data are available for children and adolescents from Central Asia. AIM: The study aimed to calculate spirometric reference curves on the basis of anthropometry, ethnicity (Kazakh vs. Russian) and living environment (urban vs. rural). SUBJECTS AND METHODS: Spirometry (FEV1, FVC and FEF25-75%) was performed and anthropometric measurements taken for 1926 male and 1967 female Kazakh children aged 7-18 years. RESULTS: Height explained almost all the variance of forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) for both sexes, while age and inspiratory circumference contributed slightly to the prediction. Moreover, FVC and FEV1 were greater in Russians than in Kazakhs and ethnicity did enter the prediction model for these parameters. The living environment had a marginal effect on spirometry. In fact, forced expiratory flow 25-75% (FEF25-75%) was slightly higher in urban than in rural females, FVC was slightly higher in rural than in urban males, while FEV1 was not affected. Finally, among several spirometric equations available in the literature, those performing better in our children were obtained in developed countries. CONCLUSION: Anthropometry was the most important predictor of spirometry. Age and ethnicity were also predictors, while the contribution of the living environment was more limited.     

Spirometric reference values for children and adolescents from Kazakhstan

Background: Spirometric parameters are influenced by several factors and many reference data are available in the literature. However, no spirometric data are available for children and adolescents from Central Asia.

Aim: The study aimed to calculate spirometric reference curves on the basis of anthropometry, ethnicity (Kazakh vs. Russian) and living environment (urban vs. rural).

Subjects and methods: Spirometry (FEV1, FVC and FEF25–75%) was performed and anthropometric measurements taken for 1926 male and 1967 female Kazakh children aged 7–18 years.

Results: Height explained almost all the variance of forced vital capacity (FVC) and forced expiratory volume in 1?s (FEV1) for both sexes, while age and inspiratory circumference contributed slightly to the prediction. Moreover, FVC and FEV1 were greater in Russians than in Kazakhs and ethnicity did enter the prediction model for these parameters. The living environment had a marginal effect on spirometry. In fact, forced expiratory flow 25–75% (FEF25–75%) was slightly higher in urban than in rural females, FVC was slightly higher in rural than in urban males, while FEV1 was not affected. Finally, among several spirometric equations available in the literature, those performing better in our children were obtained in developed countries.

Conclusion: Anthropometry was the most important predictor of spirometry. Age and ethnicity were also predictors, while the contribution of the living environment was more limited.     

Mean and instantaneous expiratory flows, FVC and FEV1: prediction equations from a probability sample of Michigan, a large industrial state

Prediction equations for FVC, FEV1, FEV1/FVC, FEF25-75%, FEF75-85%, FEF50% and FEF75% were modelled for 396 normal non-obese adult lifetime nonsmokers and continuing smokers. Subjects came from a random cross-section of the white population of Michigan, a large industrial state. In both sexes, linear models utilizing age and height were appropriate for FVC, FEV1/FVC and FEV1; flows were better described by logarithmic transformation. These regression equations provided similar predicted values for FVC and FEV1 in nonsmokers to other models in wide use. Previous equations for instantaneous flows have yielded inconsistent predicted values. It is hoped that the present equations will be useful for these measurements. Duration of cigarette smoking was a significant prediction variable for FEV1, FEV1/FVC and mean and instantaneous flows in these normal men, but not in normal women. For FEV1, the effect of each year of smoking was 40% of the effect of ageing.     

218例健康大学生肺通气功能的测定

本文对218例健康大学生进行了肺通气功能测定。根据测定的功能曲线,分别求出VC、VC％、MVV、MVV％、FVC、FEV_1、FEV_1％、MMF、FEF_(75-85%)、V_(87.5)、V_(75)、V_(50)、V_(25)、V_(12.5)和V_(50)/V_(25)等15项指标的均值,采用医学百科全书统计学软件,在AST~(486)型微机上进行多因素统计分析,建立有关指标的正常预计的回归方程,为探索大学生肺功能正常值范围及其影响因素提供有益的依据。     

Spirometric standards for non-smokers and smokers of India (eastern region)

Three hundred thirty-four healthy male non-smokers and 300 healthy male smokers of the age range 20-60 years were investigated for their spirometric lung functions by the method and technique recommended by American Thoracic Society. It was found that FVC, FEV1, FEV1%, FEF 200-1,200, FEF 25-75%, FEF 75-85%, MVV, and PEFR were significantly lower in smokers. When the subjects were blocked into several half decades these differences persisted. These functions deteriorated with age both in smokers and non-smokers, but in the former group the functions were reduced to a greater extent. Significant negative correlation was obtained between lung functions and smoking histories. Separate multiple regression equations were developed separately for non-smokers and smokers. The sensitivity of the tests was determined. The FEF 25-75% and FEV1 were found to be most sensitive in detecting early airway obstruction. When comparison of lung function was made among American, European, Jordanian, Negro, and Pakistani subjects, it was found that the former three groups are superior to the remaining. Negroes and Pakistanis are comparable to Indians in respect to their lung function. These differences in these functions between the nations of developed countries and the underdeveloped or developing countries might be attributable to the differences in their life-style, physical activity status, nutritional status, environmental condition, and race and ethnicity. The spirometric functions of Indians in the Eastern region of India are comparable to North-West Indians and superior to Southern Indians.     

Pulmonary function studies in healthy non-smoking men of Calcutta

Pulmonary function measurements were made in 104 healthy non-smoking men from Calcutta with an age range of 20–59 years. Except for peak expiratory flow rate (PEFR), all the measurements were made with the help of two 9L closed-circuit type expirographs using standard spirometric techniques. PEFR was recorded by two Wright peak flow meters. Prediction formulae were derived on the basis of age and height for all the ventilatory tests except for FEV₁%, FET and PEFR. These were predicted from age only. The prediction equation for VC, FVC, FEV₁, FEV₁%, MVV_F and PEFR were reliable, but those for forced expitatory flows and time were not. The FVC and FEV₁ values of the present subjects, standardized for age and height, were much lower than those of Americans, Caucasians, Europeans and Canadians but similar to those of Pakistani healthy adults. On comparison with the data reported from other parts of our country, it was revealed that the VC and FEV₁ values of the current study, after adjustment of age and height, were much higher than those of southern Indians but comparable with those of north-western Indians.     

A comparison of the bronchodilator effects of the same amounts of terbutaline aerosol given as a single or in divided doses.

Inhalation of 0.5 mg of terbutaline, given as a single dose or as two immediately consecutive doses of 0.25 or four consecutive doses 0.125 mg, produced the same degree of effective bronchodilation in 12 asthmatic patients at all measured intervals from 30 seconds to four hours after administration. Each treatment regimen produced equivalent improvement in FVC, FEV1, MMEF, MVV, PEFR, V Max 50% VC and V Max 25% VC. The most sensitive indicators were MMEF and V Max 50% VC. No significant side effects were encountered with this dosage and route of administration. The clinical significance of this study is that in patients who are trained in the proper use of metered dose dispensers a single 0.5 mg inhalation may be sufficient to deliver the required dose to obtain an effective and safe therapeutic response.     

Persisting airway obstruction in asymptomatic children with asthma with normal peak expiratory flow rates

Twice-daily symptom scores and peak expiratory flow readings were compared with spirometric values (FEV1 and forced expiratory flow rate between 25% and 75% of FVC [FEF 25-75]) measured at 2-week intervals in assessing airway obstruction in 20 children with asthma studied during 16 weeks. Of 56 2-week periods during which symptoms were absent, peak flow was decreased in 30 (54%), FEV1 in 20 (36%), and FEF 25-75 in 37 periods (66%). Peak flow readings were normal in 13 of 70 periods (16%) in which FEV1 was decreased, and in 33 of 113 periods (29%), in which FEF 25-75 was decreased. Of 25 periods in which symptoms were absent and peak flow was normal, 19 (76%) were associated with decreased FEF 25-75. The results confirm previous studies that indicate peak flow readings are a useful addition to symptom diaries. More importantly, they demonstrate that airway obstruction may be present in a large proportion of asymptomatic children with asthma who have normal peak flow rates and suggest that frequent assessment of FEF 25-75 is required, as well as daily monitoring of symptoms and peak flow both in trials of drug therapy and for more optimal assessment of the effectiveness of therapy in clinical practice.     

Change in pulmonary function following empyemectomy and decortication in tuberculous and non-tuberculous chronic empyema thoracis

Chronic empyema thoracis results from various etiologies. Improvement in pulmonary function after empyemectomy and decortication has proved difficult to predict when the etiology of chronic empyema thoracis is tuberculosis. The purpose of this study was to confirm the changes in pulmonary function according to the etiology after an operation. Sixty-five patients were classified into two groups according to their etiology: Group A (tuberculous) and Group B (non-tuberculous), and they were retrospectively evaluated with regard to their forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), percentage of predicted normal value of FEV1 (% FEV1) and FVC (%FVC). Empyemectomy and decortication was performed for all the patients and the two groups were similar in age, gender and preoperative spirometric parameters. In Group A (n=41), the pre- and postoperative mean values were 2.31 L and 2.8 L in FEV1, 65.8% and 80.5% in %FEV1, 2.62 L and 2.55 L in VC, 61.9% and 71.8% in %VC, respectively. In Group B (n=24), the pre- and postoperative mean values were 2.13 L and 2.49 L in FEV1, 66.4% and 73.8% in %FEV1, 2.55 L and 2.95 L in FVC, 64.9% and 71.8% in %FVC, respectively. All the spirometric parameters improved significantly in both groups compared to their preoperative values. However, no significance was shown in the rate of increase of the spirometric parameters between the two groups. In conclusion, improvement of lung function is expected after empyemectomy and decortication, regardless of the etiology of the chronic empyema thoracis.     

Spirometric reference values in Estonian schoolchildren.

This study was conducted to describe the relationship between anthropometric parameters and lung function in Estonian children, to determine the reference values for spirometry, and to compare these results with other data sets. The results are based on 1170 healthy non-smoking children (643 girls and 527 boys), aged 6-18 years. The spiroanalyser Pneumoscreen II (Jaeger) was used to register dynamic lung parameters. Natural logarithmic values of lung volumes, standing or sitting height and age were used in the final regression model. Prediction equations for forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), peak expiratory flow, forced expiratory flows when 50 and 75% of FVC has been exhaled, and mean forced expiratory flow over the middle 50% of the FVC for both sexes are presented. In comparison with recent data from European children the reference values were close for FVC, the differences were bigger for FEV1 and forced expiratory flows, especially in taller children.     

Immunological parameters and respiratory functions in patients suffering from atopic bronchial asthma after intravenous treatment with salmon calcitonin.

This study reports the effect of salmon calcitonin on airway function and peripheral blood parameters in asthmatic subjects. The premise for the study is that calcitonin is given to asthmatics that require systemic corticosteroids as a way to counter problems with calcium balance and osteoporosis, and that it has an immunosuppressive effect. Salmon calcitonin (100 IU) was administered to 18 patients with atopic bronchial asthma, and the following spirometric parameters were evaluated: forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), peak respiratory flow rate (PEFR) and forced expiratory flow rates at 25%, 50% and 75% of the forced vital capacity (FEF25%, FEF50% and FEF75%). Calcitonin significantly decreased the levels of FVC and FEV1 by 20 min after starting the infusion. The effect of 500 mg aminophylline, used as a reference drug in this study, was much more profound, with a significant increase in all investigated parameters. Also, the effect of salmon calcitonin on some immune parameters (white blood cell count, number of eosinophils, serum levels of immunoglobulins IgG, IgM and IgA, and serum levels of lymphocytes subpopulations CD3, CD4, CD8 and CD19) was determined in another group of 30 patients suffering from atopic bronchial asthma. Calcitonin at a dose of 100 IU/day subcutaneously for 3 days did not alter the immune parameters studied, thus rendering it safe for such and similar treatment schedules in a variety of medical conditions.     

Once-daily budesonide via Turbuhaler improves symptoms in adults with persistent asthma.

BACKGROUND: Previous studies have demonstrated the efficacy and safety of twice-daily budesonide Turbuhaler (Pulmicort Turbuhaler, AstraZeneca, Wilmington, DE) for the treatment of mild to severe asthma. OBJECTIVE: To compare the efficacy and safety of budesonide Turbuhaler administered once daily each morning with placebo in inhaled corticosteroid-naive adults with persistent asthma. METHODS: In this randomized, double-blind, placebo-controlled, multicenter study, 177 adults (aged 18 to 70 years) received placebo or once-daily budesonide Turbuhaler (400 microg) for 12 weeks. Efficacy variables included mean changes from baseline in forced expiratory volume in 1 second (FEV1) and AM/PM peak expiratory flow rate (PEFR), and nighttime/daytime asthma symptom scores, patient discontinuations, use of breakthrough medication (albuterol), forced vital capacity (FVC), forced expiratory flow between 25% and 75% of FVC (FEF25%-75%), and quality of life assessments. Safety was evaluated based on adverse events, physical examinations, vital signs, and laboratory tests. RESULTS: Demographic and baseline characteristics were comparable between study groups. The mean percentages of predicted FEV1 at baseline were 71.9 +/- 9.8 in patients receiving budesonide Turbuhaler and 70.6 +/- 11.0 in patients receiving placebo. Mean changes from baseline over the 12-week treatment period in FEV1 were significantly (P = 0.007) improved in patients receiving once-daily budesonide Turbuhaler compared with placebo (0.31 L and 0.17 L, respectively). Significant (P < or = 0.037) improvements over placebo also were observed in AM PEFR, nighttime/daytime asthma symptoms, and albuterol use with budesonide Turbuhaler treatment. Adverse events were generally mild or moderate in intensity and similar between study groups. CONCLUSIONS: Budesonide Turbuhaler 400 microg administered once daily in the AM is efficacious and safe for inhaled corticosteroid-naive asthmatic adults.     

Pulmonary function of herdsmen

OBJECTIVE: To determine whether the pulmonary function deficit documented previously in Fulani children is also present in adult Fulani herdsmen in northern Nigeria. SUBJECTS AND METHODS: The subjects for this study consisted of adult Fulani men from the hamlet of Magama Gumau and adult non-Fulani men from the city of Jos. Age, height, weight, mid-arm circumference (MAC), triceps skin-fold thickness, forced vital capacity (FVC), forced expiratory volume in one second (FEV1), forced expiratory flow during the middle half of the FVC maneuver (FEF25-75%), and peak expiratory flow rate (PEF) were measured. Body mass index (BMI) and FEV1/FVC were calculated for all subjects. Multiple regression analysis was performed to identify correlations between pulmonary function parameters and anthropometric variables. RESULTS: The 44 Fulani subjects and 28 urban subjects were well-matched for age and height. The Fulani men weighed significantly less than the urban men (58.5+/-9.4 versus 67.4+/-11.3 kg, p <0.001) and consequently had significantly lower BMI, MAC, and triceps skin-fold thickness. The only significant difference in pulmonary function parameters between the two groups was in FEV1/FVC (0.93+/-0.1 versus 0.85+/-0.1, p <0.001). Small but significant correlations were found between pulmonary function parameters and anthropometric variables for both study populations. CONCLUSIONS: The pulmonary function deficits documented previously in Fulani children and adolescents were not present in adult Fulani men. However, the observed elevation in FEV1/FVC in the rural Fulani men as compared to their urban counterparts, which is often seen in restrictive pulmonary patterns, deserves further study.     

Study of pulmonary function tests in 2000 healthy persons in Gujarat

This paper reports the results of spirometric studies done in the state of Gujarat in view of deriving the ventilatory norms. The study included a total of 2000 healthy nonsmoker individuals with 1369 males and 631 females. The study was done over the period from September, '92 to July, '93. The observations were tabulated, data fed on computers and the normal values for the parameters viz peak expiratory flow rate (PEFR), forced expiratory volume--1st second (FEV1) and forced vital capacity (FVC) were derived at.     

Novel regression equations predicting lung age from varied spirometric parameters

Although lung age calculated backward from regression formulas constructed for FEV(1) estimation is widely used, it possesses a couple of faults. We developed novel equations predicting lung age from varied spirometric parameters (spirometry-derived lung age (SDL-age)). Applying multiple regression analysis, equations predicting SDL-age were invented using data from 8015 never-smokers with normal spirometry (group I). Validation was made based on data from 6398 never-smokers with normal spirometry (group II). Equations were further applied for 446 subjects with airflow limitation. FEV(1), FEV(1)/FVC, FEF(50), and PEF were selected as explanatory variables for reference value of SDL-age. Normal limits of difference between SDL-age and chronological-age were ±13.4 years in the male and ±15.0 years in the female. Established equations predicted SDL-age of group II. SDL-age was older than chronological-age only in subjects with severe airflow limitation. Novel regression equations allowing prediction of reference value of SDL-age and normal limits of difference between SDL-age and chronological-age were elaborated in both genders.