EVALUATING THE FACTORS THAT RELATE TO ASTHMA SEVERITY IN ADOLESCENTS

Over the past 5 years, we have been engaged in a cross-sectional evalu ation of risk factors for higher asthma severity in adolescents aged 1 3-18. All recruitment takes place through public and private schools. The sample from which our current findings are derived includes 151 ad olescents covering a wide spectrum of asthma severity and socioeconomi c status (SES) and representing both African American and Caucasians. An asthma severity instrument has been developed and validated for the purpose of this study. This yields an asthma severity score which is a continuous variable. Female gender and the number of positive skin t ests are the best independent correlates to the asthma severity score. Among the 18 aeroallergens used in the study, the American cockroach Periplaneta americana is the only one that relates to the asthma sever ity score in a stepwise regression model. The two other cockroaches, G erman and oriental, as well as the dust mites Dermatophagoides farinae and Dermatophagoides pteronyssinus, correlate with the asthma severit y only in simple regression analysis. The relationship between asthma severity and cockroach sensitivity is strongest within the lowest-inco me per family member quartile. This is consistent with the additional observations that (1) significantly higher rates of sensitization for cockroaches are observed in the lowest-income quartile subjects and (2 ) higher levels of the cock roach allergen Bla g 1 are found in their homes. Preliminary analysis suggests that ethnic background may intera ct with environmental exposure in that, within the lowest-income quart ile, Caucasians have lower sensitization rates to cockroaches and othe r allergens compared to African Americans. Within the Caucasian popula tion, income does not appear to influence sensitization rates. The tre atment that adolescents with asthma receive for their respiratory dise ase is characterized by an overall low rate of prescribed inhaled cort icosteroids (37% in the moderately severe and severe groups). This ina dequacy in treatment is accentuated by SES: 28% of adolescents in the highest and 6% in the lowest-income quartile are prescribed these medi cations. Our findings are consistent with the hypothesis that the high er asthma morbidity and mortality observed in the African American pop ulation is related to higher exposure and sensitization to allergens s uch as those from cockroaches that are more prevalent in lower SES env ironments. It is possible that genetic factors contribute to the highe r degree of sensitization. In addition, individuals of low SES are sub jected to inadequate medical management of their asthma.