Assessment of pulmonary function test and its variability among different socio-demographic status of healthy school children of age group 9� years

Background: Pulmonary function test (PFT) is used to diagnose the underlying cause of respiratory symptoms in children and adolescents. It is also used to monitor the status of those with chronic lung diseases. In clinical practice, spirometry is the investigation of choice for the overall assessment of pulmonary function and is equated with the PFT in day to day practice the assessment of lung function. Aim and Objective: The aim of the study was to determine pulmonary function (as measured by FEV1 and FEV6) among school going children of age group 9� years and its variability with age, sex, height, and regional difference. Materials and Methods: This cross-sectional study was conducted among 703 normal healthy school children (335 boys and 368 girls) of Thiruvananthapuram city aged 9� years during 2015�16. The study group included both South Indian and North Indian children. Height, weight, and BMI were measured. All included children were tested in a sitting position with the head straight after taking written consent from parents. Spirometry was done using the instrument 揤italograph- COPD 6.� It displays FEV1 and FEV6. The FEV6 is used as a surrogate marker of FVC. Results: FEV1 and FEV6 were found to be statistically significant in the study group. Both FEV1 and FEV6 were higher in boys than girls. In both boys and girls, FEV1 and FEV6 values showed strong positive correlation with age, and height which was found to be statistically significant (P < 0.001). North Indian children have got higher FEV1 and FEV6 values than South Indian children. This was also found to be statistically significant (P < 0.001). Conclusion: Variables such as FEV1 and FEV6 values showed strong positive correlation with age and height in both sexes. By regression analysis, it was found that age, gender, and height were the significant predictors for both FEV1 and FEV6.

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

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.

Relationship between serum 25-hydroxyvitamin D and chronic obstructive pulmonary disease in males in the fifth Korean national health and nutrition examination survey / 한국영양학회지

PURPOSE: The aim of this study was to determine the relationship between serum concentrations of 25-hydroxyvitamin D [25(OH)D] and chronic obstructive pulmonary disease (COPD) prevalence. METHODS: The analysis was performed using data from the Fifth Korean National Health and Nutrition Examination Survey, a cross-sectional survey of the Korean civilian population conducted from 2010 to 2012. The analyses were restricted to males who were 40 years of age and above. Complex sample multiple logistic regression analyses were used to examine the associations of COPD prevalence with 25(OH)D and other factors. RESULTS: FEV1/FEV6 varied significantly with smoking status, age, household income, education level, occupation, body mass index (BMI), and physical activity (p < 0.05). In univariate analysis, smoking status, BMI, household income, education level, and occupation showed association with COPD (p < 0.05), but vitamin D was not associated with COPD (p = 0.078). However, when adjusted with smoking status, household income, education level, occupation, BMI, age, and smoking index, the lowest quartile of 25(OH)D showed OR 1.643 (95% CI 1.161-2.236) compared to 3rd quartile (p = 0.024). CONCLUSION: A significant relationship was observed between serum concentration of 25(OH)D and COPD.

The Complementary Role of FEV6 in Bronchodilator Reversibility Test for the Old Age / 결핵및호흡기질환

BACKGROUND: In the measurement of bronchodilator reversibility, the forced expiratory volume in one second(FEV(1)) and the forced vital capacity(FVC) are commonly used parameters and recommended criteria for the reversibility requiring an increase of more than 200ml and 12% above the baseline, respectively. However, aged patients do not often meet the criteria of an increase in volume(>200ml) even though the medical history of that patient is adequate for asthma. This study investigated the role of the forced expiratory volume in six seconds(FEV(6)) in the bronchodilator reversibility test in elderly patients. METHODS: A total of 236 patients more than 65 years of age with a FEV(1)/FVC ratio or = 80% of the predicted value, Group II: 60%

The Role of FEV6 in the Diagnosis of Obstructive Airway Disease for the Old Age

BACKGROUND: The most widely used pulmonary function test is spirometry. It is a relatively simple and noninvasive test that measures the volume of air expelled from fully inflated lungs. However, spirometry is an effort-dependent test that requires careful instruction and the full cooperation of the test subject. Because the old patients have relatively longer expiration time than the young patients, it is difficult for both old age and technician to fulfill the end of test criteria for forced vital capacity (FVC) maneuver. In the present study, we aimed to investigate whether forced expiratory volume in six seconds (FEV6) could be utilized in place of FVC in the detection of airway obstruction for the old age. METHODS: Total 353 old age (> or =65years) were enrolled in this study and performed spirometry. Subjects were divided into two groups by FEV1/FVC as the gold standard for diagnosing obstructive airway disease; Group I: 132 patients with FEV1/FVC> or =70% , Group II: 221 patients with FEV1/FVC<70% The relationship between FVC and FEV6 values were analyzed in both groups and differences between the groups were investigated. RESULTS: The mean difference of FVC and FEV6 values (FVC-FEV6) was 138.4+/-23.0 mL (5.06+/-2.86%). This difference was found to be higher in group II (189.4+/-162.5 mL, 7.0+/-5.4%) than group I (52.9+/-47.3 mL, 1.9+/-1.5%). When FEV1/FVC is taken as the gold standard, FEV1/FEV6 had negative predictive value of 87.4% and a sensitivity of 91.4% in the detection of obstructive airway disease. Conclusion: FEV6 was a relative good candidate for parameter in the detection of airway obstruction in the old age for whom it is difficult to fulfill acceptable FVC maneuver. However, additional researches are needed to determine the usefulness of FEV6 in detecting obstructive airway disease of old age.

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.