Lineages of language and the diagnosis of asthma.

Asthma, wheeze and cough are words with profoundly differing histories, etymologies and meanings. Yet their medical usage today is clustered around the diagnosis and management of a single disease. Hitherto, asthma has been a clinical diagnosis but wheeze, cough and asthma now are key terms in cross-cultural questionnaire surveys which seek information on asthma prevalence. In this essay, we examine differences in the linguistic properties of terms likely to be relevant to interpreting large-scale variations in asthma prevalence uncovered by questionnaires. We show how etymologically distinct each term is: while asthma and cough each share semantic congruencies across six European languages, albeit for different reasons, there is less congruence across these languages for the term wheeze. The medical meanings of all three terms contrast with meanings revealed by the non-medical usage of all three terms, which are highly figurative. Linguistic considerations indicate that interpretation of international questionnaires that phrase questions in terms of cough, asthma and their derivatives are likely to be more reliable for the purposes of comparing prevalence than those which deploy questions phrased in terms of wheeze.