Diarrheal Pathogens Associated With Growth and Neurodevelopment

Abstract

Background: Diarrheal pathogens have been associated with linear growth deficits. The effect of diarrheal pathogens on growth is likely due to inflammation, which also adversely affects neurodevelopment. We hypothesized that diarrheagenic pathogens would be negatively associated with both growth and neurodevelopment.

Methods: We conducted a longitudinal birth cohort study of 250 children with diarrheal surveillance and measured pathogen burden in diarrheal samples using quantitative polymerase chain reaction. Pathogen attributable fraction estimates of diarrhea over the first 2 years of life, corrected for socioeconomic variables, were used to predict both growth and scores on the Bayley-III Scales of Infant and Toddler Development.

Results: One hundred eighty children were analyzed for growth and 162 for neurodevelopmental outcomes. Rotavirus, Campylobacter, and Shigella were the leading causes of diarrhea in year 1 while Shigella, Campylobacter, and heat-stable toxin-producing enterotoxigenic Escherichia coli were the leading causes in year 2. Norovirus was the only pathogen associated with length-for-age z score at 24 months and was positively associated (regression coefficient [RC], 0.42 [95% confidence interval {CI}, .04 to .80]). Norovirus (RC, 2.46 [95% CI, .05 to 4.87]) was also positively associated with cognitive scores while sapovirus (RC, -2.64 [95% CI, -4.80 to -.48]) and typical enteropathogenic E. coli (RC, -4.14 [95% CI, -8.02 to -.27]) were inversely associated. No pathogens were associated with language or motor scores. Significant maternal, socioeconomic, and perinatal predictors were identified for both growth and neurodevelopment.

Conclusions: Maternal, prenatal, and socioeconomic factors were common predictors of growth and neurodevelopment. Only a limited number of diarrheal pathogens were associated with these outcomes.

Keywords: diarrhea; low-income countries; neurodevelopment; stunting.