No objective clinical risk factors exist for pediatric life-threatening asthma.
In this study, we address whether persistent food allergy and degree of atopy are risk factors for life-threatening asthma.
By use of a case-controlled design, children (1-16 years) ventilated for an exacerbation of asthma were enrolled. Each case was matched by sex, age, and ethnicity, with 2 controls who had attended with a non-life-threatening exacerbation. All subjects were assessed by means of a questionnaire, spirometry, and skin prick or RAST testing. The data were analyzed by conditional logistic regression.
Nineteen cases and 38 controls were enrolled. Compared with controls, cases were found to have the following risk factors: food allergy (odds ratio, 8.58; 95% CI, 1.85-39.71), multiple allergic diagnoses (4.42; 1.17-16.71), early onset of asthma (6.48; 1.36-30.85), and frequent admissions (14.2; 1.77-113.59). After regression analysis, only frequent admission with asthma (9.85; 1.04-93.27) and food allergy (5.89; 1.06-32.61) were independently associated with life-threatening asthma. Half the cases had food allergy compared with only 10% of controls.
This study demonstrates that poorly controlled asthma and food allergy are significant risk factors for life-threatening asthma. More intensive management of this high-risk group of children might help to reduce future morbidity and mortality.