December 1984, Volume 34, Issue 12

Original Article

Peak Expiratory Flow Rate in Healthy Pakistani Adults

M. Amjad Hameed  ( Department of Physiology, Army Medical College, Rawalpindi. )
Saadat Ali Khan  ( Department of Physiology, Army Medical College, Rawalpindi. )

Abstract

Peak expiratory flow rates (PEFRs) were measured in 424 healthy subjects (213 males and 211 females) from Karachi and Rawalpindi regions of Pakistan. The mean age, height and peak expiratory flow rate for males were 32.82 ± 10.52 yr, 163.5 ± 5.4 cm and 478.6 ± 63.2l/min respectively. The corresponding values for females were 35.54 ± 6.98 yr, 157.34 ± 8.2cm and 422.5 ± 42.6 l/min respectively. Body height was found to have a positive correlation with PEFR (JPMA:- 34: 363 1984).

Introduction

Peak expiratory flow rate (PEFR) recorded on Wrights peak flowmeter is commonly used for screening individuals with chronic airway obstruction both in clinical and in field studies. For the assessment and follow up of bronchial asthma PEFR is a reliable parameter. Predicted normal values for PEFR have been shown to have significant geographical and ethenic variation. The present study was carried out to collect data with regard to normal values of PEFR in healthy Pakistani adults. PEFRs have been reported by various cvorkers in different countries1-4 but no such study has been reported, for this parti­cular geographical region of the world.

Material and Methods

The study was carried out on healthy males and females, from Karachi and Rawalpindi regions. Mi subjects denied having a history of asthma, atopic phenomena, chronic bronchitis or recent upper respiratory tract infection. None of the subjects had been a regular smoker.
PEFR was recorded with a properly caliberated Wright’s peak flowmeter. Before the test, the purpose and technique of measurement were explained to each subject and they were given sufficient practice in the use of the instrument. In each case three satisfactory readings were taken, and the highest figure of PEFR, was taken as the representive value for a given individual. Height was measured in the standing position without shoes and the weight was recorded. The data was subjected to standard statistical analysis and regression equation for PEFR was obtained by method of least square deviation.

Results

A summary of the data collected from 424 subjects including 213 males and 211 females for this study is given in Table 1.

The mean age, height and peak expiratory flow rates (PEFRs) for male group are shown in Table II.

The regres sion equation to predict PEFR based on age and height is shown in Table III.

Discussion

The PEFRs recorded in the subjects were standardized for age and height. The regression of PEFR over age revealed a curvilinear relationship between age and PEFR. A similar curvilinear relationship between age and PEFRs was reported by other workers5,6 The results of a study, reported earlier by us7 also indicate the same relationship between age and PEFRs.
A linear relationship is observed between height and PEFRs. This fact concludes that tall, broad and muscular subjects have higher values of PEFRs than thinly built short individuals.
Variation between males and females for PEFRs is shown in a number of studies, The results of few of these are compared with the present study in Table IV.


The findings of this study provide the baseline data for PEFRs in normal Pakistani adults and it is expected that it will be of some help to establish normal values of PEFRs in previously untested groups of experimental and clinical conditions.

References

1. Hetzel, MR., and Dark, T.J.H. Comparison of normal and asthmatic circadian rhythms in Peak Expiratory Flow Rate. Thorax, 1980 ; 35: 732.
2. Lebowitz, M.D. Significance of intraindividual changes in maximum respiratory flow and peak expiratory flow measurement. Chest, 1982;81:566.
3. Lockhart, W., Smith, D.H., Mair, A. and Wilson, W.A. Practical experience with the peak flowmeter Br. Med. J., 1960; 1: 37.
4. Wright, B.M. and McKerrow, C.B. Maximum forced expiratory rate as a measure of ventilatory capacity. Br. Med. J., 1959; 2: 1041.
5. Greg, I. and Nunn, A.J. Peak expiratory flow in normal subjects. Br. Med. J., 1973; 3: 282.
6. Malik, S.K., Jindal, S.K., Jindal, V. and Bansal, S. Peak expiratory flow rate in healthy adults. Indian. J. Chest. Dis., 1975; 17: 166.
7. Saadat, AK., Aslam, M. and Amjad, M.H. Peak expiratory flow of healthy individuals; A com­ parative study of civilian and army personnel in Army Medical College Rawalpindi. Pak. A.F. Med.J., 1984;inpress

Journal of the Pakistan Medical Association has agreed to receive and publish manuscripts in accordance with the principles of the following committees: