Sodium cromoglycate therapy in wheezing infants: preliminary evidence of beneficial outcome at early school age

BACKGROUND: In order to affect the natural course of childhood wheezing and asthma, anti-inflammatory therapy is often prescribed for young wheezing children, but there is lack of long-term follow-up data. METHODS: Eighty-two of the original 100 children, hospitalized for wheezing under the age of 2 years in 1992-1993, were re-examined at school age in 1999. The children had participated in an open, randomized, parallel-group trial including a 4-month intervention with inhaled sodium cromoglycate (SCG) or budesonide (BUD). The baseline data, including data on atopy, eosinophilia and viral etiology, were prospectively collected on admission. RESULTS: At early school age (median 7.2 years), asthma was present in 33 (40%) children. There was less asthma in the original SCG (21%) than in the control group (54%) (OR 0.23; 95% CI 0.07-0.77). The figure was 46% in the BUD group. When the analyses were performed separately for atopic and non-atopic infants, the difference was significant only among atopics. The lowered risk for asthma in the SCG group remained significant in the multivariate logistic regression analysis when adjusted for age, sex and atopy, and further when adjusted for earlier episodes of wheezing and respiratory syncytial virus identification. However, after adjustment for blood eosinophilia, the significance was lost, albeit the risk for asthma remained low (OR 0.21; 95% CI 0.04-1.12). A sensitivity analysis, which was done by including the six drop-outs of the SCG group as unfavorable and the 12 drop-outs of other groups as favorable outcomes in the model, did not change the direction of the result (OR 0.70; 95% CI 0.26-1.89). CONCLUSIONS: An early SCG intervention in infants hospitalized for wheezing was associated with a lowered risk for early school-age asthma, especially in infants with evidence of atopy.