Malnutrition is associated with increased diarrhoea incidence and duration among children in an urban Brazilian slum.

This study was undertaken to further define the relationship between malnutrition and subsequent diarrhoeal illness among children. A cohort of 61 children under five years of age was followed for two years in an urban Brazilian slum. Nutritional status was determined at two-month intervals and was used to predict the subsequent occurrence of diarrhoea. A significant, graded association between worsened nutritional status, as measured by length- or weight-for-age, and diarrhoea incidence was found. This relationship was present for both two-month and one-year periods following nutritional assessment. The average duration of diarrhoea was also significantly longer during the two-month periods which were preceded by the worst nutritional status. Overall, the most malnourished children had nearly twice the total number of days of diarrhoea that better nourished children had. These results provide additional evidence that a significant association between malnutrition and both increased diarrhoea incidence and duration exists.