Nutritional Advice El MondoObjectives:
Evidence of an adverse influence of soil transmitted helminth (STH) infections on cognitive function and educational loss is equivocal. Prior meta-analyses have focused on randomized controlled trials only and have not sufficiently explored the potential for disparate influence of STH infection by cognitive domain. Therefore, this review article has been conducted.
Have soil transmitted helminth (STH) infections adverse influence on cognitive function and educational loss in children?
Study design:
This review article included 36 studies of 12,920 children (5-20y) that evaluated STH associated differences in psychometrically evaluated cognitive tests, educational attainment or school attendance. Of these, 5,932 children were evaluated in the context of STH treatment (with or without randomization) and 6,978 were evaluated as part of observational study.
Heterogeneity of the pooled effects in all 6 domains was high [p 0.01, I2 = 66-99%]. Application of outlier treatment reduced heterogeneity in learning domain [p = 0.12, I2 = 33%] and strengthened STH-related associations in all domains but intelligence [SMD = -0.20, p = 0.09].
Results varied by study design and ROB.
Soil-transmitted helminthiases (STH) include infections with roundworm (Ascaris lumbricoides), whipworm (Trichuris trichiura) and hookworm (Ancylostoma duodenale and Necator americanus).
Results and conclusions:
The investigators found the overall analysis showed that STH-infected/non-treated children performed significantly worse than uninfected/dewormed children in the 3 of the 6 domains including: memory [SMD = -0.31, p = 0.01], learning [SMD = -0.44, p 0.0001] and intelligence [SMD = -0.27, p = 0.03].
The investigators found in subgroup analysis among observational study designs, STH infection/non-treatment was significantly and consistently associated with deficits in memory, learning, reaction time and intelligence [SMD ranging from -0.42 to -0.23, p 0.01-0.05].
However, the investigators found in subgroup analysis among experimental intervention studies, there was no association between STH treatment and educational loss/performance in tests of memory, reaction time and innate intelligence [SMD ranging from = -0.27 to 0.17, p = 0.18-0.69].
The investigators found in subgroup analysis among studies classified as low risk of bias, STH infection/non-treatment was associated with significant deficits in memory, learning and school attendance [SMD ranging from -0.39 to -0.55, p 0.0001-0.03].
The investigators found in subgroup analysis among Schistosoma infection co-prevalent settings, associations were generally stronger and statistically robust for STH-related deficits in learning, memory and reaction time tests [SMD ranging from -0.36 to -0.55, p = 0.003-0.02].
The investigators concluded there is evidence of superior performance in 5 of 6 educational and cognitive domains assessed for STH uninfected/dewormed versus STH infected/not-dewormed school-aged children from helminth endemic regions. Cautious interpretation is warranted due to high ROB in some of the primary literature and high between study variability in most domains. Notwithstanding, this synthesis provides empirical support for a cognitive and educational benefit of deworming. The benefit of deworming will be enhanced by strategically employing, integrated interventions. Thus, multi-pronged inter-sectoral strategies that holistically address the environmental and structural roots of child cognitive impairment and educational loss in the developing world may be needed to fully realize the benefit of mass deworming programs.
Original title:
Soil-transmitted helminth infection, loss of education and cognitive impairment in school-aged children: A systematic review and meta-analysis by Pabalan N, Singian E, […], Ezeamama AE.
Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5766095/
Additional information of El Mondo:
Find more information/studies on meta-analysis and deworming right here.