Objective To evaluate the efficacy of vitamin AD combined with step-up therapy in children with asthma and its impact on humoral immunity, pulmonary function and recurrence.

Methods A total of 94 children with asthma were enrolled, and randomly divided into study group (n=47) and control group (n=47) using random number table method.The control group adopted the step-up treatment plan on the basis of conventional treatment, while the study group was treated with vitamin AD on the basis of the control group. The clinical efficacy, pulmonary function indicatorsforced vital capacity (FVC), forced expiratory volume in one second (FEV₁), FEV₁/FVC and peak expiratory flow rate (PEF)and humoral immunefunctionimmunoglobulin G (IgG), immunoglobulin A (IgA), immunoglobulin M (IgM) and immunoglobulin E (IgE) after treatment were compared between the two groups. The recurrence rateand safety of the two groups after treatment were compared.

Results The total effective rate of clinical efficacy in the study group was 93.62%, which was significantly higher than 78.72% in the control group (P < 0.05). After treatment, FVC, FEV₁, FEV₁/FVC and PEF levels were significantly higher in both groups compared to pre-treatment values, and the study group showed significantly better improvement than the control group (P < 0.05). After treatment, serum IgG and IgA levels in the study group were significantly higher than those in the control group, whereas IgM and IgE levels were significantly lower (P < 0.05). At 12 months after treatment, the recurrence rate in the study group was 4.26% (2/47), which was significantly lower than 19.15% (9/47) in the control group (P < 0.05). There was no statistically significant difference in the incidence of adverse reactions between the two groups (P>0.05).

Conclusion Vitamin AD combined with step-up therapy effectively alleviates clinical symptoms, modulates humoral immune balance, improves pulmonary function, and reduces recurrence rates in children with asthma, and has high safety.