Pulmonary function tests in Egyptian schoolchildren in rural and urban areas

Previous studies have shown a negative association between urban environments and pulmonary function.

This longitudinal study examined the effect of an urban environment on pulmonary function tests of children by comparing children from an urban and a rural area in Egypt. The effect of other factors on pulmonary function, including obesity, breastfeeding and parental atopy, was also examined.

Children aged 7-12 years from rural Shibin El-Kom and urban Cairo were enrolled in the study. Forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), forced expiratory rate and peak expiratory flow rate (PEFR) were measured 5 times over a period of 2 years, at 6-monthly intervals. Factorial repeated measures analysis of variance was used to evaluate the differences in the rate of change in FEV1 predicted%, FVC predicted% and PEFR between the children in Cairo and Shibin El-Kom. Generalized linear mixed models were used to analyse factors associated with pulmonary function test results.

Generalized linear regression showed that living in Cairo decreased log(FVC), log(FEV1) and log(PEFR). Significant differences were found in the changes occurring between the 2 locations in the last 3 visits; children in Cairo showed a smaller increase in pulmonary function.

Differences in pulmonary function in the 2 locations increased significantly with time, indicating a negative effect on lung function of living in urban Cairo. The findings could be used to help in the development of policies in Egypt and other developing countries to improve respiratory health, including promoting breastfeeding and reducing outdoor air pollution.