|Year : 2017 | Volume
| Issue : 1 | Page : 36-39
Study of dynamic lung function parameters in normal, overweight, and thin school boys
Debasish Das, Himel Mondal, Minati Patnaik
Department of Physiology, MKCG Medical College, Ganjam, Odisha, India
|Date of Web Publication||20-Mar-2017|
Department of Physiology, MKCG Medical College, Ganjam - 760 004, Odisha
Source of Support: None, Conflict of Interest: None
Background: In India, childhood undernutrition and obesity both are major health concerns. Lung functions are affected in both thin and obese children. Body mass index (BMI)-for-age is a simple tool suggested by the World Health Organization for categorizing children and adolescents below 19 years. Aim: The aim of the study was to compare dynamic lung function parameters of overweight and thin boys with normal boys. Materials and Methods: One hundred and fifty school boys of age group 12–16 years were included as a convenience sample after screening 234 students. BMI-for-age chart developed by the World Health Organization was used to categorize participants into normal (n = 50), overweight (n = 50), and thinness (n = 50) group. Forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV3, peak expiratory flow rate (PEFR), and forced expiratory flow (FEF) at the midportion of FVC (FEF25-75) were measured by MEDSPIROR. Unpaired t-test and Pearson correlation (r) were used according to the necessity. Results: Thin boys had lower FVC (P = 0.019), FEV1 (P = 0.048), FEV3 (P = 0.007), PEFR (P = 0.0002), and FEF25-75 (P = 0.003) compared to normal boys. Overweight boys showed significantly increased FVC (P = 0.019), FEV1 (P < 0.0001), and FEV3 (P = 0.0005) compared to normal boys. BMI of thin boys showed positive correlation with FVC (r = 0.49, P = 0.0003), FEV1(r = 0.40, P = 0.003), and FEV3 (r = 0.53, P < 0.0001). Correlation coefficients were not significant for BMI and dynamic lung function test parameters in normal and overweight boys. Conclusions: Thin boys have lower dynamic lung functions than normal boys. Increase in body weight may help in increasing their lung function status.
Keywords: Body mass index, forced expiratory volume, forced vital capacity, obesity, peak expiratory flow rate
|How to cite this article:|
Das D, Mondal H, Patnaik M. Study of dynamic lung function parameters in normal, overweight, and thin school boys. J Sci Soc 2017;44:36-9
| Introduction|| |
Childhood obesity is a global health issue. In India, not only childhood obesity but also undernutrition are prevalent. This double burden is challenging for effective management of child and adolescent health. Obesity is a disorder of energy balance which has its effect on multiple organs of body. Overweight children and adolescents are at risk to develop obesity and obesity-related health risks. On the other hand, undernutrition is not a disease state and can be managed with proper nutritional therapy. Body mass index (BMI) is a simple tool to measure obesity indirectly. Using only BMI below 19 years for categorization is not recommended. The World Health Organization (WHO) developed a centile-based chart for BMI-for-age which helps to categorize participants according to measured BMI and age of the participant.
Dynamic lung function parameters help us to assess the status of lung function of participants. It can be used as a tool for prognosis also. Obese children have an increased prevalence of pulmonary complication such as asthma and sleep apnea. Undernourished children are also predisposed to developing pulmonary disorders.,
There is not much information available regarding respiratory parameters among overweight, normal, and thin boys in southern Odisha. Hence, the aim of this study was to compare the dynamic lung function parameters in overweight, normal, and thin boys and to find any correlation of BMI with dynamic lung function test parameters.
| Materials and Methods|| |
After obtaining clearance from institutional ethics committee, a cross-sectional study was carried out in the postgraduate research laboratory, Department of Physiology, MKCG Medical College, Ganjam, Odisha. After taking verbal consent from teachers and parents, 234 boys were screened and their anthropometric parameters were measured. Students with any disease, deformity, or addiction were excluded from the study. BMI of the boys was plotted on BMI-for-age chart developed by WHO to categorize participants into three groups. After screening, we had purposively taken 150 boys (50 normal, 50 thin, and 50 overweight). Written consent was taken from parents of the participants after briefing about the aim of the study and procedure of tests.
Pulmonary function test
Pulmonary function tests (PFTs) were measured in the postgraduate research laboratory between 10 a.m. to 12 p.m. to avoid any circadian rhythm. Test procedures were described verbally to the participants. A demonstration of tests was also shown in a video captured beforehand. Before the actual test, a trial test was carried out. All the tests were performed in computerized MEDSPIROR instrument which uses pneumatic sensor as transducer and volume differential method for flow detection. We recorded forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV3, peak expiratory flow rate (PEFR), and forced expiratory flow (FEF) at the midportion of FVC (FEF25-75).
Data were expressed in mean and standard deviation. The normal range of BMI-for-age was taken as control group, and overweight and thin boys were taken as the study group. Dynamic PFT parameters of the study groups were compared statistically with the control group. For the study, we fixed α as 0.05 and power of study as 95%. All the statistical analyses were carried out in Microsoft Excel ® 2010 according to guidelines by Mondal and Mondal.
| Results|| |
The mean age of control group (n = 50) was 13.86 ± 1.14 years, thinness study group (n = 50) was 13.80 ± 0.97 years, and overweight (n = 50) was 13.82 ± 1.16 years. There was no statistically significant difference in age of the participants (P = 0.964). BMI of control group was 20.23 ± 1.06, thin boys was 14.57 ± 0.41, and overweight was 23.53 ± 1.17. Age and BMI of three groups are shown in [Table 1].
Comparison of dynamic lung function parameters of control group and thin group is shown in [Table 2]. All the parameters showed statistically significant decreased values in thin participants when tested statistically by t-test. In [Table 3], comparison of dynamic lung function parameters of control and overweight boys has been provided. FVC (P = 0.019), FEV1 (P < 0.0001), and FEV3 (P = 0.0005) showed statistically significant increased values in overweight boys. Values of Pearson correlation coefficient (r) showed significant positive correlation of BMI with FVC (r = 0.49, P = 0.0003), FEV1 (r = 0.40, P = 0.003), and FEV3 (r = 0.53, P < 0.0001) in thin boys. BMI of normal and overweight participants was not significantly correlated with dynamic lung function parameters. Correlation coefficients and respective P values of three groups are shown in [Table 4].
|Table 2: Comparison of dynamic lung function parameters between control group and thinness group|
Click here to view
|Table 3: Comparison of dynamic lung function parameters between control group and overweight group|
Click here to view
|Table 4: Correlation coefficients (r) and respective P values of body mass index with dynamic lung function parameters in normal, thin, and overweight boys|
Click here to view
| Discussions|| |
The result of this study indicated a significant decrease in dynamic lung functions in terms of FVC, FEV1, FEV3, PEFR, FEF25-75 in thin boys in comparison with normal boys. Study by Lad et al., Shah et al., Faridi et al., Chen et al. also found similar result. Undernutrition is responsible for decrease in muscle mass, thus weakening the respiratory muscle. Weaker respiratory muscle diminishes the ventilatory capacity. Undernutrition also decreases the defense mechanism of respiratory system. Vitamin A deficiency in undernourished children can be a factor to be considered for diminished lung volume in children.
When we compared the dynamic lung function parameters of overweight boys with the control, we found that only FVC, FEV1, and FEV3 were increased significantly in overweight boys. Other parameters though showed an increased value were not statistically significant [Table 3]. Schoenberg et al. reported that increase in muscle mass initially increases the pulmonary functions, but subsequent increase in weight may actually restrict the chest wall movement and thus may decrease the parameters. The result of our study supports the study by Saxena et al., who found insignificant group difference between normal and overweight participants.
When data tested by Pearson correlation between BMI and dynamic lung function parameters in thin boys, FVC, FEV1, and FEV3 showed a positive correlation [Table 4]. Ong et al. also studied the lung functions in malnourished children, and they found that there is a positive correlation between lung function and body weight. There was no significant correlation between BMI and dynamic lung function test parameters in normal and overweight boys. This result is concordant with the study of Muralidhara and Bhat who also found no significant correlation between BMI and pulmonary function. However, the result of this study is not corroborative with the result of Wannamethee et al. who found inverse relationship between BMI and most pulmonary function in overweight and obese individuals.
We had taken only dynamic lung function parameters to compare the groups. We had taken a convenience sample of school boys. Further studies with all lung function parameters in boys and girls of diverse age group below 19 years would reflect more precise result regarding lung function in children and adolescents.
| Conclusions|| |
Thin boys have diminished lung functions tested by dynamic lung function parameters in comparison with normal boys. Dynamic lung function parameters increase with increase in BMI in thin boys. Hence, proper nutrition therapy for thin boys may help in improving the lung functions.
We would like to thank teachers of MKCG Medical Campus High School, parents of the students, and participant students for their cooperation.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Jafar TH, Qadri Z, Islam M, Hatcher J, Bhutta ZA, Chaturvedi N. Rise in childhood obesity with persistently high rates of undernutrition among urban school-aged Indo-Asian children. Arch Dis Child 2008;93:373-8.
Ebbeling CB, Pawlak DB, Ludwig DS. Childhood obesity: Public-health crisis, common sense cure. Lancet 2002;360:473-82.
Martins VJ, Toledo Florêncio TM, Grillo LP, do CarmoP Franco M, Martins PA, Clemente AP, et al.
Long-lasting effects of undernutrition. Int J Environ Res Public Health 2011;8:1817-46.
Figueroa-Muñoz JI, Chinn S, Rona RJ. Association between obesity and asthma in 4-11 year old children in the UK. Thorax 2001;56:133-7.
Kantarci F, Mihmanli I, Demirel MK, Harmanci K, Akman C, Aydogan F, et al.
Normal diaphragmatic motion and the effects of body composition: Determination with M-mode sonography. J Ultrasound Med 2004;23:255-60.
Arora NS, Rochester DF. Effect of body weight and muscularity on human diaphragm muscle mass, thickness, and area. J Appl Physiol Respir Environ Exerc Physiol 1982;52:64-70.
Mondal H, Mondal S. Sample size calculation to data analysis of a correlation study in Microsoft Excel ®
: A hands-on guide with example. Int J Clin Exp Physiol 2016;3:180-9. [Full text]
Lad UP, Jaltade VG, ShiSode-Lad S, Satyanarayana P. Correlation between body mass index (BMI), body fat percentage and pulmonary functions in underweight, overweight and normal weight adolescents. J Clin Diagn Res 2012;6:350-3.
Shah HD, Shaikh WA, Patel D, Singh SK. Dynamic lung functions in underweight Gujarati Indian adolescents boys. Natl J Community Med 2012;3:142-5.
Faridi MM, Gupta P, Prakash A. Lung functions in malnourished children aged five to eleven years. Indian Pediatr 1995;32:35-42.
Chen Y, Rennie D, Cormier YF, Dosman J. Waist circumference is associated with pulmonary function in normal-weight, overweight, and obese subjects. Am J Clin Nutr 2007;85:35-9.
Kassaye T, Becklake MR, Receveur O, Hanley JA, Johns T. Association between Vitamin A status and lung function level in children aged 6-9 years in Wukro wereda, Northern Ethiopia. Int J Epidemiol 2001;30:457-64.
Schoenberg JB, Beck GJ, Bouhuys A. Growth and decay of pulmonary function in healthy blacks and whites. Respir Physiol 1978;33:367-93.
Saxena Y, Saxena V, Dvivedi J, Sharma RK. Evaluation of dynamic function tests in normal obese individuals. Indian J Physiol Pharmacol 2008;52:375-82.
Ong TJ, Mehta A, Ogston S, Mukhopadhyay S. Prediction of lung function in the inadequately nourished. Arch Dis Child 1998;79:18-21.
Muralidhara DV, Bhat MR. Some aspects of the pulmonary functions in underweight and overweight human subjects. Thai J Physiol Sci 2007;20:3-7.
Wannamethee SG, Shaper AG, Whincup PH. Body fat distribution, body composition, and respiratory function in elderly men. Am J Clin Nutr 2005;82:996-1003.
[Table 1], [Table 2], [Table 3], [Table 4]