Allergic asthma in different population groups in the western Cape. Causative and complicating factors

Allergic asthma is a disease with a well-defined aetiology, the recognition and elimination of which could be achieved with relatively simple and inexpensive prophylactic treatment. Some of the well-known factors--respiratory tract infections, exposure to cigarette smoke, specific antigens and regular application of prophylactic treatment--which could cause or complicate asthma were studied in groups of white and coloured patients. More respiratory tract infections occurred in coloured patients and they were more exposed to their own and secondary cigarette smoke. Pets and grass pollen allergenicity was more common among whites while allergy to Aspergillus fumigatus and Ascaris lumbricoides was found more frequently among coloured patients. Both white and coloured patients had problems with regular prophylactic control of their symptoms with inhaled beta-stimulants, even after an average of two education sessions per patient, but this was of greater dimension for the coloured (60%) than the white group (27%) (P less than 0.001). It is not possible to separate causative from genetic factors when studying asthma in different population groups, but recognition of prevailing causative factors for each group could stimulate an educational approach aimed at control by prevention rather than treatment of acute attacks.