Submitted to: Biological Trace Element Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/4/2007
Publication Date: 1/8/2008
Citation: Combs, G.F., Hassan, N., Dellagana, N., Stabb, D., Fischer, P., Hunt, C., Watts, J.J. 2008. Apparent efficacy of food-based calcium supplementation in preventing rickets in bangladesh. Biological Trace Element Research. 121:193-204.
Interpretive Summary: Rickets occurs in southeastern Bangladesh in communities with intakes of calcium that are less than half of recommended levels. Therefore, rickets in this area appears to be caused by dietary Ca-deficiency. We tested that hypothesis in a double-blind clinical trial 158 high-risk 1-5 yr. old children to whom we offered daily a milk powder-based beverage daily providing either 50, 250 or 500 mg Ca, or 500 mg Ca plus multi-vitamins, iron and zinc. After 13 months of this intervention, no child showed rachitic leg signs or significant radiological evidence of active rickets, and all showed carpal ossification normal for age. These results suggest that rickets in Bangladesh is of the calcium-deficiency type and that even the small increases in calcium intakes (50 mg/d) can be useful in supporting normal bone development in this high-risk population.
Technical Abstract: Background: Rickets occurs in southeastern Bangladesh. Previous studies have found that calcium (Ca) intakes in this area are less than half of recommended levels but that vitamin D status is not deficient, suggesting the disease to be due to Ca-deficiency. Objective: The objective was to determine whether increased Ca intakes can prevent rickets in a susceptible group of children living in a rickets-endemic part of Bangladesh. Design: A 13 mo., double-blind, trial was conducted with 158 1-5 yr. old children randomized to four treatments consisting of a milk powder-based beverage given daily, 6 days/wk, and providing either 50, 250 or 500 mg Ca, or 500 mg Ca plus multi-vitamins, iron and zinc. Bone health was evaluated by physical examination and radiographic analyses; biochemical markers included plasma calcium, phosphorus and 25-hydroxycholecalciferol. Anthropometry was used to assess general nutritional status. Results: Upon screening, 194 children presented with no rachitic leg signs and had serum AP in the upper decile (>260 u/dl) of the screened cohort of 1749 children. When 183 of those apparently healthy children were re-screened after the pre-trial period, 23 showed rachitic leg signs, suggesting an annual risk of 21.5% in this cohort. Of those without leg signs after the pre-trial period, none showed rachitic leg signs or significant radiological evidence of active rickets, and all showed carpal ossification normal for age after 13 mos. of intervention. Conclusions: These results suggest that even the lowest supplement of Ca (50 mg/d) was useful in supporting normal bone development in this high-risk population.