Study of pulmonary function tests in workers of rurally located flour mills

Background: Agro-based industrial works like flour milling are a significant component in the industrial arena of Kerala. In milling industry, dusts are produced in substantial quantities and inhalation of which can result in pulmonary impairment in workers. In such situations, spirometric evaluation can aid in the diagnosis and prognosis of pulmonary diseases. Aims and Objectives: The aims of this study were to assess the effect of flour dust on pulmonary function among flour mill workers and to study the variation in pulmonary function among workers according to duration of exposure and their working environment in the factory. Materials and Methods: A cross-sectional study was conducted in three wheat flour mills. Subjects were selected after proper exclusion and after getting informed consent. In the present study, 79 flour mill workers aged more than 20 years and employed for more than 1year, were considered and their FVC,FEV1,FEV1/FVC,PEFR and FEF25-75% values were assessed. The objective was to find out the effect of their duration of employment and exposure to dust on their spirometric parameters based on their type of job and age. These parameters were tested using a portable electronic spirometer in the factory premises. Results: The study showed no significant relation of these parameters with duration of employment and dust exposure. However, there was significant reduction in FVC and FEV1 with increasing age. Conclusion: Even though apparently normal PFT values are obtained in many subjects, these may be on the extremes of normal spectrum.

Comparison of the effect of recumbent body positions on dynamic lung function parameters in healthy adults

Background: Pulmonary function parameters can be altered with the change in body position. Therefore, physiological basis behind such consequent influence is essential to be understood. Pulmonary function tests are generally conducted in the erect sitting posture as it is more feasible and comfortable. However, bedridden patients are unable to do so and only few studies are found on recumbent postures. Thus, to comfort such patients in breathing, need arises to meet this requisite investigation to conclude the best recumbent body posture. Aim and Objectives: To compare and assess forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), FEV1/FVC ratio, forced expiratory flow of during 25�% expiration (FEF25�%, and peak expiratory flow rate (PEF) in the Supine, Crook-lying and Fowler抯 position. Materials and Methods: The present research was carried out on 128 healthy adults to measure FVC, FEV1, FEV1/FVC ratio, FEF25�% and PEF using a computer-based spirometer in the Supine, Crook-lying and Fowler抯 position. One-way Analysis of Variance with Tukey HSD post-hoc test was utilized between each body postures by evaluation of their mean values. Results: This study consisted of 128 subjects (males 57, females 71) with mean age of 21.62 � 1.75 years, mean weight 59.71 � 9.97 kg, mean height 164.68 � 9.30 cm and Body mass index 21.91 � 2.38 kg/m2. Fowler抯 posture showed significantly (P < 0.05) higher value in all spirometric parameters as compared to other two postures. Outcome of the study showed all spirometric parameters value- greater in the Fowler抯 posture than that of Supine or Crook-lying posture. Conclusion: The implication of this research is that it will meet the need of selection of the most suitable substitute posture for better pulmonary functioning in bedridden people.

Pulmonary function tests in subclinical hypothyroidism-a comparative cross-sectional study

Background: Subclinical hypothyroidism (SCH) reflects the earliest stage of thyroid dysfunction with subjects having normal free thyroid hormones T3, T4 with elevated Thyroid-stimulating hormone (TSH) values. Hypothyroidism may depress the central ventilator control and affects respiratory muscle strength which is linearly related to the thyroid hormone levels. In hypothyroidism, the impairment of pulmonary functions may be initiated at the subclinical stage of hypothyroidism. Aim and Objectives: The present study was designed to derive Forced Vital capacity (FVC), Forced expiratory volume in 1 second (FEV1), FEV1/FVC, Peak expiratory flow rate and FEF 25–75 % in subclinical hypothyroid subjects and to compare the values with that of healthy controls. Materials and Methods: A cross-sectional comparative study was conducted in subjects aged between 25 and 60 years in which 85 subclinical hypothyroid cases were selected after proper exclusion and informed consent. 85 age and sex matched healthy controls were also studied. Statistical package for social sciences version 18 was used for statistical analysis. Results: All spirometric variables were found to be lower in subclinical hypothyroid subjects than in healthy controls and the abnormalities were of mixed pattern-both obstructive and restrictive. All values obtained were statistically significant (P < 0.05). Conclusion: Patients with SCH should be regularly screened with pulmonary function tests as respiratory derangement starts even at this stage. This will help for early diagnosis and treatment, and to prevent future complications.

FEV1/FEV6 y FEV6 una alternativa para FEV1/FVC y FVC en la detección de obstrucción de vías respiratorias / FEV1/FEV6 and FEV6 an alternative for FEV1/FVC and FVC in the detection of airway obstruction

INTRODUCCIÓN: el objetivo de este estudio fue verificar si los puntos de corte fijos y el límite inferior de lo normal (LLN) para el volumen espiratorio forzado en un segundo (FEV1) y el volumen espiratorio forzado en 6 segundos (FEV6) FEV1/FEV6 y el FEV6 son una medida alternativa para el FEV1 y la capacidad vital forzada (FVC), FEV1/FVC y la FVC en la detección de la enfermedad pulmonar obstructiva crónica (EPOC), en una muestra de pacientes del oriente boliviano. MÉTODOS: se analizaron un total de 92 pruebas espirométricas, 66 varones y 26 mujeres con riesgo de EPOC. La población del estudio incluyó a residentes de la ciudad de Santa Cruz de la Sierra-Bolivia (ciudad cosmopolita) de 35 a 90 años de edad. RESULTADOS: la sensibilidad y la especificidad fueron del 97,0% y el 96,9%, respectivamente, cuando se compararon los valores de corte fijos de FEV1/FEV6 de 0,73 con los de FEV1/FVC < 0,7 como regla estándar, según las recomendaciones del global obstructive lung diseases (GOLD) para detectar la obstrucción de las vías respiratorias. La sensibilidad y la especificidad fueron de 93,4% y 81,2%, respectivamente, cuando el LLN de FEV1/FVC y FEV1/FEV6 fueron utilizados. CONCLUSIONES: en conclusión, el FEV6 es un sustituto válido de la CVF para detectar la obstrucción de las vías respiratorias, ya sea utilizando puntos de corte fijos o el LLN. Se necesitan más estudios para verificar estos resultados en una población más grande y para establecer los valores predictivos espirométricos locales.

INTRODUCTION: the aim of this study was to verify if fixed cut-off points and lower limit of normal (LLN) for forced expiratory volume in one second (FEV1)/FEV6 and FEV6 as an alternative for FEV1/forced vital capacity (FVC) and FVC are valid for the detection of obstructive lung disease in a sample of Bolivian subjects. METHODS: a total of 92 spirometric consecutive tests from subjects, 66 males and 26 females at risk for COPD were analyzed. The study population included residents of city Santa Cruz de la Sierra, (Bolivia) aged from 35 to 90 yrs., from various ethnical origins (cosmopolitan city). RESULTS: sensibility and specificity were 97.0% and 96.9%, respectively when fixed cut-off values of FEV1/FEV6 of 0.73 was compared to FEV1/FVC<0.7 as standard, according to GOLD recommendations to detect airway obstruction. Sensibility and specificity were 100% and 89.5%, respectively when LLN of FEV1/FVC and FEV1/FEV6 were used. CONCLUSIONS: in conclusion, FEV6 is a valid surrogate for FVC to detect airway obstruction, either using fixed cut-off points or LLN. Further study is needed to verify these results in a larger population and to establish local spirometric predicted values

A comparative study of lung function among sawmills workers in central India

Background: Many of the studies have put forth the hypothesis that sawdust deteriorates lung function, increases the incidence and prevalence of diseases of the respiratory system, and can predispose to cancer and deaths. Deterioration of lung function can be tested by pulmonary function tests. Several studies have shown respiratory disorders in sawmill workers, including the reduction of pulmonary function tests, but there is a paucity of such studies in Central India; hence, in this study, we tried to study comparative lung function among sawmill workers. Objective: The objective of this study was as follows: (i) To study the lung function of workers in sawmill industry, (ii) comparative assessment of lung function with those of controls, and (iii) to study the effect of occupational exposure to wood dust. Materials and Methods: The study was carried out in the sawmills in Nagpur city from September 2013 to December 2015. Sawmill workers were the study group and local government workers as comparison group. Each worker was examined in a separate room away from the workplace. Spirometry was done to assess the lung function using the UK’s Compact Vitalograph. Subjects in the control group were also examined with the spirometry. The lung function values of sawmill workers compared with the control and the difference in them was assessed both numerically and statistically. Results: Mean of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), forced expiratory flow25–75, and peak expiratory flow rate was significantly decreased among sawmill workers as compared to control group (P < 0.05), but FEV1/FVC ratio was significantly elevated among sawmill workers (P < 0.05). Conclusion: We have concluded that sawmill workers suffered from obstructive or restrictive type of pulmonary disorder, but the predominant type was restrictive lung disease.

Pulmonary function test in patients of type 2 diabetes mellitus

Background: We are today witnessing a pandemic of diabetes mellitus (DM), globally and nationally. DM and its complications have become the most important contemporary and challenging health problems. Diabetes is not associated with any specific pulmonary symptom and hence periodic screening for lung disease is not done in diabetic patients. However, an extensive microvascular circulation and an abundant connective tissue in the lung raise the possibility that the lung may also be a target organ in diabetic patients. The aim and objectives were to study the pulmonary function of individual with type 2 diabetes mellitus patients by performing spirometry.Methods: Study included non-smoker diabetic patients, who had no history of respiratory disease, were selected for this study and undergone pulmonary function test by spirometry. The study was conducted at department of General Medicine Shri Ram Murti Smarak Institute of Medical Sciences, Bareilly, Uttar Pradesh, India.Results: Present study, author found that there was significant derangement in the spirometric readings in the diabetic patients. The FEV1/FVC values further declines as the duration of diabetes increased.Conclusions: Spirometric values (FVC, FEV1, FEV1/FVC) were consistently lower in subjects with type 2 diabetes mellitus. The effect on FVC predicted % was found to be more pronounced in subjects whose duration of DM was more than 5 years.

Clinical evaluation pulmonary function test in type II Diabetes Mellitus

Introduction: Chronic hyperglycemia is associated with continuing damage, dysfunction and failure of various organs, especially the eyes, kidneys, nerves, heart, lungs, and blood vessels. The pathogenesis is thought to involve both a micro-angiopathic process and non-enzymatic glycosylation of tissue proteins. It has been demonstrated that pulmonary complications in diabetes are due to thickening of walls of alveoli, alveolar capillaries, and pulmonary arterioles and these changes cause pulmonary dysfunction. Aim of the study: To correlate the lung function in type II diabetes with duration of diabetes and to find out whether it is obstructive or restrictive pattern. Materials and methods: Totally 100 subjects participated in the study. Out of 100 participants, 50 were type II diabetes forming the study group and the remaining 50 were normal subjects forming the control group. A detailed history and thorough clinical examination were carried out. Inclusion criteria were Apparently healthy individuals with type II diabetic patients on oral hypoglycemic drugs and having diabetes for more than 2 years duration of age group 35 – 55 years. Thorough clinical examination and history were obtained from the subjects in order to determine the health status of the individual. Anthropometric measurements like height, weight were measured and BMI was calculated. Glycemic status for the participants was measured by doing fasting & postprandial blood sugar. HbA1c was determined. Results: The Mean (±SD) of HbA1c of controls was 3.16 ± 0.482 and for the study group was 5.38 ± 1.174, showed that the controls and study group with good glycemic control were selected for the study. The mean (±SD) of FEV1 for the control group were 91.40±11.236 and for diabetic group were 81.15±16.523. It was found to be significantly reduced (P= 0.002). The mean (±SD) of FVC for the control group was 81.85±9.211and for diabetic group was 73.75±13.933. The mean (±SD) of PEFR for the control group was 98.85±21.996 and for diabetic group was 85.95±24.045. The mean values of Mathew Jeraud. Clinical evaluation pulmonary function test in type II Diabetes Mellitus. IAIM, 2019; 6(9): 37-42. Page 38 FVC and PEFR were found to be reduced in diabetic group when compared to controls and were statistically significant. The mean (±SD) of FEV1/FVC% for the control group was 117.05±7.250 and for diabetic group was 116.58±7.071. The mean (±SD) of FEF25-75% for the control group was 136.73±26.056 and for diabetic group was 125.63±41.009. The mean (±SD) of MVV for the control group was 65.20±15.010 and for diabetic group was 58.80±16.530. The mean values of FEV1/FVC%, FEF25-75%, and MVV were reduced in diabetic group when compared with the control group but not statistically significant. Conclusion: The pulmonary dysfunction may be one of the earliest and easily measurable nonmetabolic alterations in diabetes. Therefore the patients with diabetes are suggested to undergo pulmonary function testing periodically. As spirometry is much more reliable, valid and simple test, it is time to include the spirometer as a tool for monitoring diabetes. Strict glycemic control and regular breathing exercises to strengthen respiratory muscles are necessary to improve the pulmonary function in type II diabetics.

Which is better among FEV1/FVC and FEV1/SVC in obstructive airway disease?

Background: Forced expiratory volume in 1 second (FEV1) to forced vital capacity ratio (FVC) is being used to diagnose the obstructive lung diseases. Forced manoeuvre (FVC) or relaxed/slow manoeuvre (SVC) can be used to determine vital capacity (VC). In healthy individuals the difference between SVC and FVC (SVC-FVC) is minimal whereas in the presence of airway obstruction this difference will become significant. The present study was done with the objective to detect and compare the airway obstruction by determining the FEV1/FVC and FEV1/ SVC ratios.Methods: This was a prospective cross-sectional study done at OPD, Government Thiruvoteeswarar hospital of thoracic medicine/Kilpauk medical college during the period from September 2016 to February 2017among the patients presenting with symptoms of obstructive airway disease. The sample comprised of 353 patients who underwent spirometry according to standard of ATS/ERS guidelines. As per the criteria, the patients are classified into four groups, by spirometry.Results: The analysis of FEV1/FVC revealed the presence of airway obstruction in 131 (37%) individuals compared to 165 (46%) individuals by the analysis of Fev1/SVC ratio. In the obstruction and mixed groups, the difference in vital capacity SVC – FVC is statistically superior (p<0.05) when compared to normal and restriction groups.Conclusions: The FEV1/SVC ratio detected the presence of airway obstruction in more individuals than did FEV1/FVC ratio and hence FEV1/SVC considered as more reliable factor in the detection of obstructive airway diseases.

Comparison between FEV1/FEV6 and FEV1/FVC as screening of chronic obstructive pulmonary disease

Objective: To compare FEV1/FEV6 to the standard spirometry (FEV1/FVC) as a screening tool for COPD. Methods: This cross-sectional study was conducted at Hospital Tuanku Fauziah, Perlis, Malaysia from August 2015 to April 2016. FEV1/FEV6 and FEV1/FVC results of 117 subjects were analysed. Demographic data and spirometric variables were tabulated. A scatter plot graph with Spearman’s correlation was constructed for the correlation between FEV1/FEV6 and FEV1/FVC. The sensitivity, specificity, positive and negative predictive values of FEV1/FEV6 were determined with reference to the gold standard of FEV1/FVC ratio <0.70. Receiver-operator characteristic (ROC) curve analysis and Kappa statistics were used to determine the FEV1/FEV6 ratio in predicting an FEV1/FVC ratio <0.70. Results: Spearman’s correlation with r = 0.636 (P<0.001) was demonstrated. The area under the ROC curve was 0.862 (95% confidence interval [CI]: 0.779 - 0.944, P<0.001). The FEV1/FEV6 cut-off with the greatest sum of sensitivity and specificity was 0.75. FEV1/FEV6 sensitivity, specificity, positive and negative predictive values were 93.02%, 67.74%, 88.89% and 77.78% respectively. There was substantial agreement between the two diagnostic cut-offs (κ = 0.634; 95% CI: 0.471 - 0.797, P<0.001) Conclusions: The FEV1/FEV6 ratio can be considered to be a good alternative to the FEV1/FVC ratio for screening of COPD. Larger multicentre study and better education on spirometric techniques can validate similar study outcome and establish reference values appropriate to the population being studied.

Study of FEV1/FVC Ratio In Relation to BMI in Young Group of Rohilkhand Region.

Background: The aim of study was to to assess respiratory indices in underweight and overweight young group (subcategory) and compare the same with normal weight controls (in the age group of 18 to 30 years). Methods: In the present study 210 subjects were included, aged between 18 yrs-30 yrs after applying inclusion and exclusion criteria. The groups (n=210, case= 132 and control= 78) are divided into group A, B, C, D, E and F respectively each having 21, 78, 40. 35, 29 and 7 subjects on the basis Of international classification of BMI. Results: In our study mean predicted value of FEV1/FVC ratio in group A 84.02±31.24(underweight), group C 86.83±29.46(pre-obese), group D 92.10±13.31(obese class 1),group 93.72±9.49 ( obese class 2) and group F191.02±22.24( obese class 3), when compared to control group B 87.95±26.77 was found to be decreased in group A and increased in other obese group , but it was within normal range in all groups and no statistical difference found between different groups (P value>0.05). Conclusion: After analyzing the data, we did not observe any statistically significant difference in FEV1/FVC between the control and underweight and overweight group.

Correlation between abdominal muscle strength and pulmonary function in subjects with low back pain

Introduction: The diaphragm is man's main respiratory muscle. The role of the abdominal muscles is seen in both quiet and forceful breathing. Abdominal muscle function could be affected in subjects with back pain. Few studies are done about the relation between expiratory muscle strength and pulmonary function. So the aim of this study was to evaluate the correlation of abdominal muscle strength with pulmonary function in patients with low back pain. Materials and methods: Sixty subjects with low back pain were included in the study. Subjects with history of acute or chronic respiratory disorders were excluded. Abdominal muscle strength was measured by curl up test and FEV1/FVC and peak expiratory flow rate (PEFR) was measured to assess pulmonary functional. Results: Using Spearman test for correlation between abdominal muscle strength and FEV1/FVC (r= - 0.27, p=0.03), and between abdominal muscle strength and PEFR (r=0.34, p=0.007) was seen. Conclusion: There was a weak correlation between abdominal muscle strength and pulmonary function in subjects of low back pain.

Serum Vitamin D Concentration in Asthmatic Children and Its Association with Recovery Time from an Asthma Exacerbation.

Introduction: The relationship of vitamin D and asthma is known but the association between vitamin D and time required to recover from acute asthma exacerbation has not been studied. Aims: To find an association between serum vitamin D levels and time required to recover from an asthma exacerbation (recovery days) in asthmatic children from age 5 to 15 years. And to find association of other risk factors of asthma on recovery days. Study Design: It was a cross sectional study. Place and Duration of Study: Department of Paediatrics, Qatar Hospital Orangi Town and Abbassi Shaheed Hospital, Karachi, between February 2012 to June 2014. Methodology: We included 99 asthmatic children (60 male and 39 females; age range 5 to 15 years) at the time of an acute asthma exacerbation. Spirometry was done using Vitalograph (alpha) (UK). FEV1/FEVC ratio <80 % was used to confirm acute asthma exacerbation. Serum vitamin D levels were measured by chemiluminescence method using Abbott's ARCHITECT clinical chemistry analyzer. Children were followed up for confirming recovery by spirometry. FEV1, FVC and FEV1/FVC ratio within the reference ranges (The Thoracic Society of Australia and New Zealand and Polgar) were taken as normal. Results: Applying Poisson regression model it was found out that that there was no association between vitamin D levels and time to recover from asthma (P =.398). 28.6% (n=2) children showed early recovery when recovery days were associated with exposure to home environment (P =0.000). Conclusions: Despite the fact that 95% of the subjects with asthma had either vitamin D deficiency or insufficiency but there was no significant association between vitamin D levels and the time required to recover from an asthma exacerbation. Further studies are needed to establish the role of vitamin D in asthma.

The smoking cessation effect on pulmonary function of chronic obstructive pulmonary disease and its mechanism / 安徽医科大学学报

Objective To explore the smoking cessation intervention impact on lung with genetic polymorphism of SOD3. The aim is to further reveal the importance of smoking cessation intervention on early COPD patients. Meth-ods 60 COPD patients with smoking cessation intervention and 40 COPD patients without intervention ( the control group) were enrolled in this study. Limosis peripheral blood was taken and whole blood corpuscle genomic DNA was extracted. The genetic polymorphism of SOD3 genes was determined by ligase detection reaction and polymerase chain reaction ( LDR-PCR) and serum SOD3 concentration was measured using ELISA. Lung function between the two groups before and after intervention were detected by microspirometry. Results ①The FEV1% and the FEV1/FVC% were increased after 3 and 6 months intervention in smoking cessation group(P0.05). ③The serum of SOD3 concentration of COPD intervention group and the control have no significance after intervention ( P>0.05 ) . ④ The serum of SOD3 concentration a-bout CC and CG/GG genotype in COPD intervention group have no significance after 3 and 6 months intervention ( P>0.05 ) . Conclusion Smoking cessation interventions for patients with COPD pulmonary function improves significance in short-term. But different SOD3 genotypes have no effect on lung function after intervention. Smoking cessation intervention has no effect on in serum SOD3 concentration of COPD patients, and has no relationship be-tween the expression of SOD3 genetype.

Effects of Pulmonary Rehabilitation on Lung Functions In Patients with COPD.

Background: The importance of pulmonary rehabilitation (PR) as a therapeutic measure for COPD patients is well known. Objective: To evaluate the effects of PR program by pursed lip breathing (PLB) and diaphragmatic breathing (DB) on FVC, FEV1, FEV1/FVC ratio in male patients with moderate stable COPD. Methods: This prospective study was conducted in the Department of Physiology, BSMMU, Dhaka from July 2010 to June 2011 on 116 male stable moderate COPD patients aged 50 to 65 years. They were enrolled from the out patient department of the Department of Medicine of BSMMU and NIDCH Dhaka. They were grouped as control (56 patients without PR) and experimental (60 patients with PR). The experimental patients were advised to perform PR program for 30 minutes duration per session at home twice daily, for consecutive 60 days along with the standard drug treatment of COPD. On the contrary, the control patients were advised to continue their standard drug treatment alone for consecutive 60 days. For the assessment of spirometric lung function status, FVC, FEV1, FEV1/FVC ratio of all subjects were recorded on day 0 and day 60 for both the group by a portable digital MicroDL Spirometer and the statistical analysis was done by independent sample ‘t’ test and paired Student’s ‘t’ test. Results: FVC and FEV1 value were significantly increased in comparison to the control patients after 60 days of follow up. On the other hand, post exercise value of FEV1/FVC ratio was decreased but it was not statistically significant. Conclusion: The study reveals improvement of lung functions with this sort of combination of PR program in stable COPD patients.

FEV1, FVC, FEV1/FVC ratio in children of 7-14 years of age from Western Rajasthan.

Background: The knowledge of pulmonary function tests (PFTs) is a basic requirement to understand the respiratory physiology for all medical physiologists and clinicians Pulmonary Function Tests provide objective evidence of nature and severity of lung disease. Objective: To observe FEV1, FVC, FEV1/FVC ratio in healthy male and female school children from 7-14 years of age in Western Rajasthan and to find out the relationship of FEV1, FVC, FEV1/FVC ratio with their height, weight, BSA and sex Methods: The present study was carried out on 112 male and 76 female children of 7-14 years. For Pulmonary Function Tests, FEV1, FVC and FEV1/FVC along with anthropometric data of each subject was recorded.. Data were analyzed by unpaired t test, Pearson correlation coefficient test, simple and multiple regression analysis. Results: FVC and FEV1 values were found significantly (p<0.001) higher in male than those of female. Significant positive correlation of FVC and FEV1 whereas non significant negative correlation of FEV1/FVC were observed with age, height, weight, body surface area in all children. Conclusion: As the weight, age, height and BSA of subjects increases, FEV1 and FVC increases while FEV1/FVC ratio decreases in both the sexes.

FVC, FEV1, FEV1/FVC ratio and FEF25-75% in End-stage renal disease (ESRD) patients undergoing maintenance haemodialysis.

Background: End-stage renal disease causes multiple pulmonary complications and lung functions are decreased in ESRD patients undergoing maintenance haemodialysis. Objectives: To observe FVC, FEV1, FEV1/FVC ratio and FEF25-75% in ESRD patients undergoing maintenance haemodialysis to evaluate their lung functions status. Methods: This cross sectional study was carried out in the Department of Physiology, BSMMU, Dhaka, from July 2011 to June 2012. For this, 30 ESRD patients aged 25-55 years undergoing maintenance haemodialysis with less than 1 year duration were studied and 30 age, sex matched healthy subjects were taken as control. Patients were selected from the Nephrology department of BSMMU, Dhaka. FVC, FEV1, FEV1/FVC ratio and FEF25-75% were measured by a Digital Spirometer. For statistical analysis Independent Sample‘t’ test and One way ANOVA test were performed as applicable. Results: The mean percentage of predicted values of FVC, FEV1 and FEF25-75% were significantly lower in patients except FEV1/FVC ratio which was almost similar to control. 63.33% patients had restrictive and 36.67% patients had both restrictive and obstructive (small airway obstruction) feature. Conclusion: This study concluded that some pulmonary functions were markedly reduced in ESRD patients undergoing maintenance haemodialysis. In addition most of the patients were suffering from restrictive and some of them were affected with both obstructive and restrictive type of pulmonary disorders.

A comparative study of pulmonary functions in different age groups.

Background and objectives: The respiratory system changes with age and understanding these changes helps detect and prevent respiratory dysfunctions in the elderly. Pulmonary function, as measured by spirometry is an important predictor of morbidity and mortality of elderly persons. The aim of the present study was to see the effects of aging on pulmonary functions. Methods : The study included 150 subjects of different ages from 20 years and above. Subjects were divided in six groups depending on their age. (1) 20-29 yrs (2) 30-39 yrs (3) 40-49 yrs (4) 50-59 yrs (5) 60-69 yrs (6) 70 yrs and above. 25 subjects were included in each group. FVC , FEV1, FEV1 /FVC%, PEFR, FEF25%-75%, MVV were measured. Results: Comparing 20-29 yrs with 70 yrs and above show mean FVC (4.33 vs 1.68 litre, p<0.001) ,FEV1(3.91 vs 1.19 litre p<0.001), FEV1 /FVC%(90.30 vs 70.0 p<0.001), PEFR(9.81 vs 3.31 lit/sec p<0.001), FEF25%-75%(6.65 vs 1.89 lit/sec p<0.001), MVV(93.94 vs 55.96 lit/min p<0.001). Conclusion: Our study concluded that FVC, FEV1, FEV1/FVC, PEFR, FEF25- 75% and MVV decrease with age. It is probably a result of decreased strength of expiratory muscles, decreased chest wall compliance and increased tendency of airways to close during forced expiratory effort causing air trapping in the lungs.

Pulmonary Function Studies of Healthy Non-smoking Male University Students of Kolkata, India — Revisited

Background: Pulmonary function tests (PFTs) need to be revisited in light of rapid economic growth and industrial development. Questions have been raised about the validity of existing population-specific norms for predicting PFTs, and therefore, the present study aimed to determine the applicability of existing norms for PFTs in young healthy non-smoking male university students of Kolkata. Methods: PFTs were carried out for 87 non-smoking male university students who were randomly sampled from the University of Calcutta, Kolkata, India. Results: The PFTs data obtained in this study did not show a significant variation with that obtained in a previous study. Significant (P < 0.001) differences in the forced expiratory volume in 1 s (FEV1%) and peak expiratory flow rate (PEFR) between the two studies may be attributed to differences in the age and body height, which exhibited significant correlations with the vital capacity (VC), forced vital capacity (FVC), FEV1, FEV1%, and PEFR. Regression equations have been computed to predict PFTs parameters from age and body height. Conclusion: Pulmonary function in the university students of Kolkata was found to have remained mostly unchanged in the last 24 years. The equations computed in this study are considered preferable owing to their substantially smaller standard error of estimate (SEE) than those proposed in the previous study.

Airway Measurement for Airway Remodeling Defined by Post-Bronchodilator FEV1/FVC in Asthma: Investigation Using Inspiration-Expiration Computed Tomography

PURPOSE: Airway remodeling may be responsible for irreversible airway obstruction in asthma, and a low post-bronchodilator FEV1/FVC ratio can be used as a noninvasive marker of airway remodeling. We investigated correlations between airway wall indices on computed tomography (CT) and various clinical indices, including post-bronchodilator FEV1/FVC ratio, in patients with asthma. METHODS: Volumetric CT was performed on 22 stable asthma patients who were taking inhaled corticosteroids. Airway dimensions were measured at four segmental bronchi using in-house software based on the full-width/half-maximum method. Parameters included luminal area, wall thickness (WT), wall thickness percentage (WT%), wall area percentage (WA%), bronchial-to-arterial diameter (BA) ratio on inspiration CT, airway collapsibility (AC), and air trapping index (ATI). Correlations were analyzed between CT parameters and clinical indices, including %FEV1, FEV1/FVC, FEF25-75%, and post-bronchodilator FEV1/FVC ratio. RESULTS: Post-bronchodilator FEV1/FVC showed significant correlations with WT%, WT, BA ratio, AC, and ATI (r=-0.503, -0.576, 0.454, 0.475, and -0.610, respectively). WT showed negative correlations with FEV1/FVC and FEF25-75% (r=-0.431 and -0.581), and WT% was negatively correlated with %FEV1, FEV1/FVC, and FEF25-75% (r=-0.434, -0.431, and -0.540, respectively). WA% showed correlations with FEF25-75% and body mass index (r=-0.459 and 0.453). The BA ratio was positively correlated with %FEV1 (r=0.459) and FEF25-75% (r=0.479). AC showed strong positive correlation with FEV1/FVC (r=0.592), and ATI showed negative correlations with FEV1/FVC (r=-0.534) and FEF25-75% (r=-0.591). CONCLUSIONS: WT%, WT, BA ratio, and AC on inspiration and expiration CT are good indices for measuring airway remodeling defined by post-bronchodilator FEV1/FVC in stable asthma patients treated with inhaled corticosteroids.

Normal Predictive Values of Spirometry in Korean Population / 결핵및호흡기질환

BACKGROUND: Spirometry should be compared with the normal predictive values obtained from the same population using the same procedures, because different ethnicity and different procedures are known to influence the spirometry results. This study was performed to obtain the normal predictive values of the Forced Vital Capacity(FVC), Forced Expiratory Volume in 1 Second(FEV1), Forced Expiratory Volume in 6 Seconds(FEV6), and FEV1/FVC for a representative Korean population. METHODS: Based on the 2000 Population Census of the National Statistical Office of Korea, stratified random sampling was carried out to obtain representative samples of the Korean population. This study was performed as a part of the National Health and Nutrition Survey of Korea in 2001. The lung function was measured using the standardized methods and protocols recommended by the American Thoracic Society. Among those 4,816 subjects who had performed spirometry performed, there was a total of 1,212 nonsmokers (206 males and 1,006 females) with no significant history of respiratory diseases and symptoms, with clear chest X?rays, and with no significant exposure to respiratory hazards subjects. Their residence and age distribution was representative of the whole nation. Mixed effect models were examined based on the Akaike's information criteria in statistical analysis, and those variables common to both genders were analyzed by regression analysis to obtain the final equations. RESULTS: The variables affecting the normal predicted values of the FVC and FEV6 for males and females were age2, height, and weight. The variables affecting the normal predicted values of the FEV1 for males and females were age2, and height. The variables affecting the normal predicted values of the FEV1/FVC for male and female were age and height. CONCLUSION: The predicted values of the FVC and FEV1 was higher in this study than in other Korean or foreign studies, even though the difference was < 10%. When compared with those predicted values for Caucasian populations, the study results were actually comparable or higher, which might be due to the stricter criteria of the normal population and the systemic quality controls applied to the whole study procedures together with the rapid physical growth of the younger generations in Korea.