National study of health and growth: respiratory symptoms and height in primary schoolchildren.

An analysis of the relationship between the height of primary schoolchildren in England and Scotland and their respiratory symptoms as reported by their parents showed that children with morning cough, day and night cough, wheeze and asthma or bronchitis in the preceding 12 months were shorter than those without these symptoms. In subsequent analyses account was taken of differences in social and biological factors as measured by father's social class, sibship size and parent's height. The relationship between height and asthma remained statistically significant. Morning cough and day and night cough were related to short stature in children living in more deprived conditions. The number of respiratory symptoms was inversely related to height but once the children with asthma were excluded from the analysis the trend tended to disappear. There was also some evidence that children with respiratory symptoms gained less height in a year than those without. Our results indicate that, with the exception of asthma, the association between respiratory symptoms and height in primary school children is only marginal. Nevertheless in lower social classes and where sibling size is large common respiratory symptoms are related to short stature.