A Study of PEFR and its Relation with Demographic and Anthropometric Parameters in Northern Chennai Primary School Children

INTRODUCTION: Pulmonary function tests of various types are utilized clinically and epidemiologically to measure functional status in order to assess the disease1 (Lebowitz, 1991)1. Though they do not provide a specific diagnosis, they help us to understand the physiology, course and progress of the respiratory diseases, assess the severity and help in the management of respiratory diseases (Swaminathan,1999)2. Pulmonary function testing in a child differs from that in adult, mainly because of the volume change that occurs from birth through the period of growth to the adulthood. These differences influence technique, methodology and interpretation (Kulpati, 19923; Polger19714 Robertson, 19905). However, most of them are cumbersome, expensive and difficult to obtain reproducible results in children. The peak expiratory flow rate (PEFR) measurement is simple, reproducible and reliable way of judging the degree of airway obstruction in various obstructive pulmonary diseases, especially in asthma. Peak expiratory flow rate is easily measured by using a mini- Wright’s peak flow meter (Wright,19786), which is easy to use, reliable and can be recorded even by the patients or by the parents at home (Wille,7; deHamel8; Burns, 9 ; Perks, 10,11). This instrument is cheap, portable, easy to understand and useful for physicians in managing children with respiratory diseases, particularly valuable for assessing children aged as low as 3 years, as younger children cannot perform the other pulmonary function test reproducibly (Milner and Ingram,197012). AIM OF THE STUDY: 1. To find out normal baseline PEFR for the Northern Chennai Children Age between 6 to 10 years. 2. Correlate the PEFR with various demographic and anthropometric parameters. DISCUSSION: The PEFR has now been accepted as a simple and reliable way of monitoring the severity of bronchial asthma and assessing the response to treatment. The mini Wright peak flow meter is cheap, easily available instrument and its use in Western countries now extends to the home monitoring for asthmatics to have a baseline PEFR recorded when they are asymptomatic and clinically free of wheezing and wherever possible. The daily variations in PEFR can serve as a guide to knowing the severity of asthma, the effectiveness of the current therapy and need for any additional treatment. It has been shown that pulmonary function especially lung volumes show racial and ethnic differences.40,41 In this study we wanted to establish the reference values for PEFR for Northern Chennai children. In present study descriptive analysis of dependable variables (age, height, weight, BSA, chest circumference and chest expansion) shows slightly higher mean value in boys when compared to girls. The PEFR were also higher in boys than in girls due to more muscle mass in the boys when compared to girls. But the girls between the age group of 9 to 10 years have higher value than boys. This cannot be explained. The regression analysis showed the study variables had statistically significant linear positive correlation with PEFR. Regarding this, height had a high linear positive correlation with PEFR flowed by age and Body surface area. On comparing our data with the previously published Western values, we found that PEFR values of our children were low. CONCLUSION: 1. In our study baseline reference value for northern Chennai was derived which can be utilized for office practice. 2. In our study boys showed higher value of PEFR than girls except in 9-10yrs age group. 3. When compare to other studies northern Chennai children had lower PEFR values. 4. In our study height, age and BSA had high positive linear correlation with PEFR followed by weight, chest circumference and chest expansion