EXERCISE-INDUCED BRONCHOSPASM - A PILOT SURVEY IN NAIROBI SCHOOL-CHILDREN

Exercise-induced bronchospasm (EIB), a common feature of asthma in chi ldren, has been used as the outcome measure in community-based surveys of childhood asthma to circumvent difficulties arising from relative lack of objectivity in the use of questionnaires in communities with d ifferent cultural and language orientations. We report here the result s of the first community-based study of childhood asthma in Kenya usin g EIB as the outcome measurement. The data was collected in a pilot st udy to develop methodology for a larger subsequent study. The survey t argeted grade four children in five Nairobi City Council schools each representing a neighbourhood social economic status (SES), Out of 597 eligible, 408 children took part in the study (68 % participation rate ). EIB defined as decline in FEV1 of 15 % or more, postexercise was fo und in 10.5% (95% CI; 10.3,10.7) of the children studied, the highest rate reported so far in Africa. While boys were more likely to exhibit EIB compared to girls, the prevalence of EIB tended to decrease with age, especially among children residing in low SES neighbourhoods wher e the EIB prevalence rates tended to be lower compared to those among children from higher SES neighbourhoods, However, none of these differ ences was statistically significant. This study confirms the feasibili ty of undertaking exercise challenge tests in the African context and we recommend that additional studies of similar nature be carried out in other populations of Africa to explore the potential of using an ex ercise test as a marker of asthma in epidemiologic studies.