Minerals and Trace Elements Intakes and Food Consumption Patterns of Young Children Living in Rural Areas of Tibet Autonomous Region, P.R. China: A Cross-Sectional Survey.

BACKGROUND AND OBJECTIVES: Several studies revealed clinical signs of stunting and rickets among rural populations of Tibet Autonomous Region (T.A.R.), and especially amid children. Further, these populations are affected by a bone disease named Kashin-Beck disease (KBD). However, little is known about the dietary status of this population. This survey aimed to assess the usual intakes of young Tibetan children living in rural areas around Lhasa for energy, water, and ten minerals and trace elements (Na, K, Ca, P, Mg, Fe, Zn, Cu, Mn, and Se) involved in bone metabolism. DESIGN: A cross-sectional survey was designed. Totally, 250 pre-school children aged 3-5 years living in rural areas were enrolled. The 24-h food recall method was used to collect the intakes for two days, during two different seasons (September 2012 and April 2013). Because Tibetan foods are mainly derived from local agriculture and artisanal production, a combination of food composition tables was compiled, including specific and local food composition data. RESULTS: The Chinese dietary recommended intakes are not met for most of the elements investigated. Intake of sodium is much too high, while usual intakes are too low for K, Ca, Zn, Cu, and Se. Bioavailability of Ca, Fe, and Zn may be of concern due to the high phytic acid content in the diet. CONCLUSION: These nutrient imbalances may impact growth and bone metabolism of young Tibetan children. The advantages of the implementation of food diversification programs are discussed as well as the relevance of supplements distribution.

Effect of calcium and vitamin D on growth, rickets and Kashin-Beck disease in 0- to 5-year-old children in a rural area of central Tibet.

OBJECTIVE: To evaluate the effect of calcium (15 mmol/day) and vitamin D (625 µg/month), as single supplement or in combination, vs. no supplement on growth, clinical signs of rickets and Kashin-Beck disease (KBD) and dental health. METHODS: Prospective controlled trial involving children aged 0-5 years living in four groups of villages in a KBD-endemic rural area of central Tibet who received either calcium and/or vitamin D or no supplement. The cohort was followed over 3 years. Primary outcome was the impact of the different supplementation regimes on KBD, rickets and growth; secondary outcomes were impact on urinary levels of calcium and phosphorus, biomarkers of bone and cartilage turnover, and dental health. RESULTS: No difference was observed between the four groups with regard to anthropometric data, rickets, KBD, urinary levels of CrossLaps(®) and CartiLaps(®) . Weight for height or age, mid-upper arm circumference and skinfold thickness decreased in the four groups. Height for age increased and the prevalence of KBD fell in the four groups. Dental health was better in the group receiving calcium and vitamin D. Urinary calcium levels increased after 3 years of follow-up in all groups; the group receiving vitamin D had a higher increase (P-value: 0.044). The same global increase was observed for urinary phosphorus levels; the group receiving calcium had a higher increase (P-value: 0.01). CONCLUSIONS: Calcium and vitamin D failed to improve growth and bone metabolism of children living in a KBD-endemic rural area. Calcium and vitamin D supplementation improved dental health.

Growth, nutritional status, and signs of rickets in 0-5-year-old children in a Kashin-Beck disease endemic area of Central Tibet.

UNLABELLED: In order to describe the growth of 0-5-year-old Tibetan children living in a Kashin-Beck disease (KBD) endemic rural area and to examine the relationship between anthropometric indicators and clinical signs of rickets, we analyzed the baseline data of a cohort of 668 children enrolled in a prospective program of calcium and vitamin D supplementation. Tibetan children suffer from growth retardation. Z score of weight-for-age, height-for-age, weight-for-height was below -2 in 32.5%, 27.7%, and 12.1% of the children, respectively. Clinical signs of severe rickets are highly prevalent. Underweight, stunting, and clinical rickets increases with age. Prevalence of malnutrition was higher in the presence of signs of rickets. The proportion of children with a head circumference Z score < -2 was lowest when signs of rickets were observed. CONCLUSION: Stunting and underweight are frequent and probably associated with rickets.

Selenium and iodine supplementation of rural Tibetan children affected by Kashin-Beck osteoarthropathy.

BACKGROUND: Kashin-Beck disease is an osteoarthropathy endemic in selenium- and iodine-deficient areas around Lhasa, Tibet. OBJECTIVE: We assessed the efficacy of selenium supplementation on disease progression. DESIGN: A double-blind, randomized controlled trial of selenium supplementation was carried out in 324 children aged 5-15 y who had Kashin-Beck disease. Two hundred eighty children received iodized oil before being randomly assigned to receive selenium or placebo, and a control group of 44 subjects was not supplemented at all. Clinical and radiologic signs, selenium status, urinary iodine, and thyroid function were evaluated at baseline and at 12 mo. RESULTS: The frequencies of joint pain, decreased joint mobility, and radiologic abnormalities were not significantly different between the 3 groups at 12 mo. Height-for-age z scores increased significantly in the subjects who received placebo and iodine or selenium and iodine. In contrast, unsupplemented control subjects did not recover from growth retardation. Serum selenium concentrations at 12 mo were within the reference range and were significantly greater in the selenium-iodine group than in the placebo-iodine group. Serum thyroid hormone concentrations were within the reference ranges after the administration of iodine, and these values were not significantly affected by selenium supplementation. CONCLUSIONS: The results of this study do not rule out the possibility that selenium may help to prevent the occurrence of Kashin-Beck disease. However, selenium supplementation had no effect on established Kashin-Beck disease, growth, or thyroid function once iodine deficiency was corrected. These results suggest that iodine, but not selenium, deficiency should be corrected in Tibetan children with Kashin-Beck disease.