Spirometric values in Tunisian children: relationship with pubertal status

Pulmonary function of adolescents from Tripura, a North-eastern state of India

Objective:

Spirometric evaluation of pulmonary function has been evolved as clinical tool in diagnosis, management, and follow-up of respiratory disorders. There are very few studies on normative reference values of pulmonary function parameters for adolescents from Tripura, a North-eastern state of India. The present study was aimed to evaluate pulmonary function and their predictors in male and female adolescents of Tripura.

Materials and Methods:

A total of 640 (320 from tribal and 320 non-tribal) healthy, non-smoking male and female school children (age 10-14 years) from four different districts of Tripura were randomly sampled for the study. The pulmonary function parameters analysed included forced vital capacity (FVC), forced expiratory volume in 1 second (FEV₁), peak expiratory flow rate (PEFR), forced expiratory flow between 25% and 75% expired volume (FEF_25-75%), ratio of FEV₁/FVC and maximum voluntary ventilation (MVV).

Results:

The results revealed that body weight, body mass index (BMI), PEFR, FEF_25-75% and MVV are significantly high among male tribal children in comparison to non-tribal children. Height, weight, waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), PEFR and MVV were found to be significantly more in tribal girls. In case of adolescents from Tripura, most of the pulmonary function parameters correlated with anthropometric parameters of the subject like height, weight, BMI, WHR, and WHtR.

Conclusion:

From the present study, it can be concluded that both anthropometric and pulmonary function status of tribal and non-tribal adolescents from Tripura are comparable. The computed regression norms may be used to predict pulmonary function of adolescents from Tripura by using anthropometric indices.

The relationship between physical functional capacity and lung function in obese children and adolescents

BACKGROUND

There is no consensus regarding obesity repercussions for lung function in children and adolescents. Therefore, the aim of the study was to determine whether obesity is associated with poor physical conditioning and damaged lung function in children and adolescents, and to correlate lung function with six-minute walk test (6MWT) results.

METHODS

This cross-sectional study included 38 obese subjects of both sexes, ranging between 5 and 17 years of age, as well as 56 control subjects paired by sex and age for the 6MWT, and 39 subjects for spirometry. Subjects performed spirometry according to the guidelines of the American Thoracic Society (ATS) and the European Respiratory Society. The obese group repeated spirometry after receiving bronchodilator (BD) treatments. Physical performance was evaluated via the 6MWT according to ATS guidelines.

RESULTS

The obese group demonstrated lower forced expiratory volumes in the first second compared with the control group based on forced vital capacity indices (p < 0.01), findings consistent with airway obstruction in 36.8% of patients in the obese group. Walking distances were shorter in the obese group than in the control group. Changes in lung function did not correlate directly with performance on the 6MWT among obese patients. However, there was a correlation between lung function and variables indicative of effort during exercise.

CONCLUSION

In the present study, the obese group walked shorter distances and demonstrated lower values in some markers of lung function. However, there is no relationship between their physical conditions and these test results. Therefore, we cannot conclusively state that poor physical performance results from damaged pulmonary function.

Multi-ethnic reference values for spirometry for the 3-95-yr age range: the global lung function 2012 equations

The aim of the Task Force was to derive continuous prediction equations and their lower limits of normal for spirometric indices, which are applicable globally. Over 160,000 data points from 72 centres in 33 countries were shared with the European Respiratory Society Global Lung Function Initiative. Eliminating data that could not be used (mostly missing ethnic group, some outliers) left 97,759 records of healthy nonsmokers (55.3% females) aged 2.5-95 yrs. Lung function data were collated and prediction equations derived using the LMS method, which allows simultaneous modelling of the mean (mu), the coefficient of variation (sigma) and skewness (lambda) of a distribution family. After discarding 23,572 records, mostly because they could not be combined with other ethnic or geographic groups, reference equations were derived for healthy individuals aged 3-95 yrs for Caucasians (n=57,395), African-Americans (n=3,545), and North (n=4,992) and South East Asians (n=8,255). Forced expiratory value in 1 s (FEV(1)) and forced vital capacity (FVC) between ethnic groups differed proportionally from that in Caucasians, such that FEV(1)/FVC remained virtually independent of ethnic group. For individuals not represented by these four groups, or of mixed ethnic origins, a composite equation taken as the average of the above equations is provided to facilitate interpretation until a more appropriate solution is developed. Spirometric prediction equations for the 3-95-age range are now available that include appropriate age-dependent lower limits of normal. They can be applied globally to different ethnic groups. Additional data from the Indian subcontinent and Arabic, Polynesian and Latin American countries, as well as Africa will further improve these equations in the future.

[Lung function prediction equations in Tunisian children: taking into consideration pubertal stage]

OBJECTIVE

The purpose of this study was to set lung function prediction equations in Tunisian children with standing height and pubertal stage as the independent variables.

METHODS

Spirometric values were measured with a Minato portable Spirometer in 684 asymptomatic Tunisian children (351 boys and 333 girls), 8 to 16 years of age. The specific parameters of pulmonary function that were measured included Forced Vital Capacity (FVC), Forced Expiratory Volume in 1 second (FEV(1)), Peak Expiratory Flow (PEF), Maximal Expiratory Flow at 50% of the vital capacity (MEF(50)), and Maximum Mild Expiratory Flow between 25 and 75% (MMEF(25-75)). The pubertal status was assessed for males and females according to the Tanner method.

RESULTS

A large variation was observed in the distribution of children's age and height by pubertal stages in both sexes. Multiple regression equations for FVC, FEV(1), MEF(50), MEF(25-75), and PEF for both sexes are presented with standing height and pubertal stage as the independent variables.

CONCLUSION

The establishment of validated reference values relevant to the ethnic group of the local population should significantly improve medical surveillance of respiratory diseases in Tunisian children.

[Determining factors of pulmonary function in healthy Tunisian children]

Introduction Pulmonary function parameters are known to vary with age, sex, height and ethnic extraction. No normal values have been reported for pulmonary function in Tunisian children. Moreover, little attention has been paid to the factors affecting the development of lung function in Tunisian healthy children. State of art Birth weight and height, physical activity level, anthropometric, socioeconomic and environmental factors could influence the development of lung function in healthy children. Perspectives The studies conducted by our group have allowed us 1) to set reference values for spirometry in healthy Tunisian children; 2) to indicate that, in Tunisian adolescents, the use of only one morphological parameter such as height, is not sufficient, but the pubertal status could be taken into account to standardize the lung function and 3) to show the main predictive factors for pulmonary development to be the anthropometric factors such as height, weight, maximal inspiratory and expiratory thoracic perimeter, sex and age, and the environmental conditions (type of heating) in our population of healthy Tunisian children. Conclusion These findings should improve medical surveillance of respiratory diseases, stipulation of preventive and therapeutic measures in Tunisian children.