RESUMO
OBJECTIVE: To identify factors associated with asthma associated with increased sickle cell anemia (SCA). STUDY DESIGN: Children with SCA (N = 187; mean age 9.6 years, 48% male) were classified as having "asthma" based on parent report of physician diagnosis plus prescription of asthma medication (n = 53) or "no asthma" based on the absence of these features (n = 134). Pain and acute chest syndrome (ACS) events were collected prospectively. RESULTS: Multiple variable logistic regression model identified 3 factors associated with asthma: parent with asthma (P = .006), wheezing causing shortness of breath (P = .001), and wheezing after exercise (P < .001). When ≥2 features were present, model sensitivity was 100%. When none of the features were present, model sensitivity was 0%. When only 1 feature was present, model sensitivity was also 0%, and presence of ≥2 of positive allergy skin tests, airway obstruction on spirometry, and bronchodilator responsiveness did not improve clinical utility. ACS incident rates were significantly higher in individuals with asthma than in those without asthma (incident rate ratio 2.21, CI 1.31-3.76), but pain rates were not (incident rate ratio 1.28, CI 0.78-2.10). CONCLUSIONS: For children with SCA, having a parent with asthma and specific wheezing symptoms are the best features to distinguish those with and without parent report of a physician diagnosis of asthma and to identify those at higher risk for ACS events. The value of treatment for asthma in the prevention of SCA morbidity needs to be studied.