Forced Expiratory Flow 25 ? 75 % is an important index of early airway dysfunction ? Results from the coal power plant ? Sri Lanka
Abstract
Objectives: Objective was to determine the association between coal exposure and respiratory functions.
Methods: Descriptive cross sectional study was done in Norochchole coal power plant. A group of 80 workers consisted of Coal handlers (CH) and non-coal handlers (NCH) were interviewed using an interviewer administered questionnaire. Their cardiovascular and respiratory systems were examined and detailed spirometry was done. Sample of 80 was divided into coal handlers (n=51) and non-coal handlers (n=29). Their spirometry data had been analysed at uni-variate level using t test and Pearson’s correlation at multi-variate level.
Results: Measured Forced Expiratory Flow 25 – 75% (FEF) was (Mean ± SD) 2.7 ± 1.0 l/s for NCH and 3.2 ± 1.1 l/s for CH, p =0.031. Percentage FEF was (Mean ± SD) 63.0 ± 26.4 l/s for NCH and 75.0 ± 25.4 l/s for CH, p =0.047. Hence both measured and percentage FEFare significantly lower among non-coal handlers.
Measured FEF and percentage FEF were significant correlates with duration of work with a Pearson correlation and a p value of -0.242, 0.031; -0.239, 0.033 respectively.
Conclusions: This study highlights the use of FEF 25 – 75% as an important index in detecting early impairment of lung function. Previously undetected and unexpected early impairment of lung functions are noted among non-coal handlers. This study recommends the need of further studies to assess the coal exposure and lung function of the people living in the vicinity.
