C. Nokes et al., Evidence for an improvement in cognitive function following treatment of Schistosoma japonicum infection in Chinese primary schoolchildren, AM J TROP M, 60(4), 1999, pp. 556-565
Citations number
48
Categorie Soggetti
Envirnomentale Medicine & Public Health","Medical Research General Topics
A double-blind, placebo-controlled, treatment trial was conducted in Sichua
n, China to investigate the unique and combined effects on the cognitive fu
nction (working memory) of children after treating geohelminth infections w
ith albendazole and treating Schistosoma japonicum infection with praziquan
tel. One hundred eighty-one children 5-16 years of age participated. At bas
eline, the praziquantel and placebo groups were similar in all background c
haracteristics. Three months after praziquantel treatment, there was a sign
ificant reduction in the prevalence and intensity of S. japonicum infection
. There were significant age group by praziquantel treatment interaction ef
fects in three of the five cognitive tests, Fluency, Picture Search, and Fr
ee Recall, with effects being strongest in the youngest children (5-7 years
old). Exploratory analysis within the youngest children showed a significa
nt positive main effect of treatment on Fluency (P < 0.001), after controll
ing for sex, anthropometric, and parasitic and iron status. There was also
a treatment by height-for-age interaction (P = 0.03) and a treatment by iro
n status interaction (P = 0.024) on Fluency. There was a treatment by S. ja
ponicum intensity interaction (P < 0.001) on Free Recall, but the main effe
ct of treatment on Picture Search was not significant (P = 0.058). Younger
children and those who are physically the most vulnerable are likely to ben
efit the most from the treatment of S. japonicum infection in terms of impr
oved performance on tests of working memory.