Effect of Albendazole Treatments on the Prevalence of Atopy in Children Living in Communities Endemic for Geohelminth Parasites: A Cluster-Randomized Trial
Cooper PJ, Chico ME, Vaca MG, et al. Lancet. 2006;367:1598–1603
PURPOSE OF THE STUDY. To determine if repeated antihelminthic treatments with albendazole affect the prevalence of atopy and clinical indices of allergy among children who live in parasite-endemic communities.
STUDY POPULATION. Children (N = 2373) attending the second to seventh year of primary education at 1 of 68 rural schools in a tropical and subtropical region of Ecuador.
METHODS. Children were cluster randomized by school to receive albendazole treatment every 2 months for 12 months or no treatment. The primary outcome was the proportion of children with at least 1 positive skin-test result to an environmental allergen after 12 months; secondary outcomes included the proportion of children with reported allergy symptoms, flexural dermatitis, and exercise-induced bronchospasm. No placebo was used, but the investigators who evaluated the children were blinded to their treatment-group assignment.
RESULTS. At baseline, there was an inverse association between geohelminth infection and skin-test reactivity (odds ratio: 0.78; 95% confidence interval: 0.65–0.95). Of children who attended albendazole-allocated schools, 91.5% received all 7 albendazole doses; albendazole treatment by parents was reported for 29.4% of the children allocated to no-treatment schools. After 12 months, the prevalence of geohelminth infection declined from 69.3% to 20.5% in the treatment group and from 74.6% to 65.7% in the no-treatment group. There was no evidence of an increase in the prevalence of atopy among children who received albendazole (17%) compared with those in the no-treatment group (17%; age- and gender-adjusted odds ratio: 0.97; 95% CI: 0.68–1.39). Both groups had similar reported allergy symptoms, flexural dermatitis, and exercise-induced bronchospasm after 12 months.
CONCLUSIONS. After 12 months, the prevalence of atopy did not increase among school-aged children who were treated with albendazole, compared with children who were not treated.
REVIEWER COMMENTS. Management of allergic conditions has increasingly focused on prevention and reduction of risk factors. Small intervention studies have shown increased atopy associated with regular antihelminthic treatment. Although this study was larger, it had a high dropout rate (31%), and antihelminthic treatment of children in the no-treatment group may have biased the results toward the null. It is important to note that the protective effect of geohelminth exposure against atopy may be greater during the first few years of life than by school age. However, these results suggest that treatment of school-aged children with antihelminthics over 12 months does not put them at greater risk of atopy.
- Copyright © 2007 by the American Academy of Pediatrics