CD4 and asthma: Binary logistic regression analysis and the Wald X2 test of each regression coefficient further showed that the level of CD4+CCR6+CRTh2+memory Th2 cells (EXP, 8.986; 95 % CI, 1.886–42.816; P < 0.01) and wheezing frequency (EXP, 0.127; 95 % CI, 0.023–0.703; P < 0.05) were risk factors for asthma in these children (Table 3).