Early childhood diarrhea is associated with diminished cognitive function 4 to 7 years later in children in a northeast Brazilian shantytown

Am J Trop Med Hyg. 2002 May;66(5):590-3. doi: 10.4269/ajtmh.2002.66.590.


Diarrhea is well recognized as a leading cause of childhood mortality and morbidity in developing countries; however, possible long-term cognitive deficits from heavy diarrhea burdens in early childhood remain poorly defined. To assess the potential long-term impact of early childhood diarrhea (in the first 2 years of life) on cognitive function in later childhood, we studied the cognitive function of a cohort of children in an urban Brazilian shantytown with a high incidence of early childhood diarrhea. Forty-six children (age range, 6-10 years) with complete diarrhea surveillance during their first 2 years of life were given a battery of five cognitive tests. Test of Non-Verbal Intelligence-III (TONI) scores were inversely correlated with early childhood diarrhea (P = .01), even when controlling for maternal education, duration of breast-feeding, and early childhood helminthiasis (Ascaris or Trichuris). Furthermore, Wechsler Intelligence Scale for Children (WISC-III) Coding Tasks and WISC-III Digit Span (reverse and total) scores were also significantly lower in the 17 children with a history of early childhood persistent diarrhea (PD; P < .05), even when controlling for helminths and maternal education. No correlations were seen between diarrhea rates and Wide Range Assessment of Memory and Learning subtests or WISC-III Mazes. This report (with larger numbers of participants and new tests) confirms and substantially extends previous pilot studies, showing that long-term cognitive deficits are associated with early childhood diarrhea. These findings have important implications for the importance of interventions that may reduce early childhood diarrheal illnesses or their consequences.

MeSH terms

  • Brazil / epidemiology
  • Child
  • Child, Preschool
  • Cognition Disorders / epidemiology
  • Cognition Disorders / etiology*
  • Cryptosporidiosis / epidemiology
  • Diarrhea / complications*
  • Diarrhea / epidemiology
  • Diarrhea / parasitology
  • Educational Status
  • Female
  • Giardiasis / epidemiology
  • Helminthiasis / epidemiology
  • Humans
  • Income
  • Male
  • Mothers
  • Nutritional Status
  • Poverty
  • Regression Analysis