The Chakaria food system study: household-level, case-control study to identify risk factor for rickets in Bangladesh

Objective: A comprehensive, multiround survey of local food systems in a rickets-endemic area of Bangladesh was conducted to identify household-level risk factors for rickets. Design: A household-level, case - control study was conducted in a rickets-endemic area, Chakaria, with planned comparisons between households with one or more rachitic child and neighboring households with no affected children. Setting: A rickets-endemic area of southeastern Bangladesh, Chakaria. Subjects and methods: An interview-based survey was conducted in six villages in Chakaria with 199 households with at least one child showing physical signs consistent with rickets and 281 households with no affected children. Results: Households with rachitic children in Chakaria had more children, more pregnant or lactating women, and fewer adults than unaffected households in that community. Affected households tended to rely on farming for their livelihood and tended to have less economic activity as indicated by less outstanding debt than their neighbors. Households with rickets were at significantly greater risk of pneumonia than were other households. Calcium undernutrition was severe and widespread in Chakaria due to a food system that offered very little of the element in accessible forms. Household diets were based on cereals and starchy vegetables. Rice and fish constituted the major source of calcium for most households, although dairy products, when used, were very important calcium sources, particularly for young children. In fact, the use of dairy products was the only household choice that led to substantial increases in the calcium intakes of children, and households that used dairy products tended to show increased calcium intakes for all of their members. Conclusions: The risk of a Chakarian household having a child with rickets appeared to be related to its economic status. Although this might be expected to be manifest as limitations in food access and/or use, rickets households failed to show a dietary pattern associated with rickets. Calcium undernutrition was prevalent and, thus, would appear to be a predisposing factor for rickets; however, calcium undernutrition was prevalent in Chakarian households with and without rickets. Therefore, it is probable that another precipitating factor(s) play a role(s) in the etiology of rickets in Chakaria.