Prevalence of vitamin D deficiency in Samarkand, Uzbekistan
Abstract
Background. Clinical rickets is a childhood bone disorder that is infrequently seen in the Western World. It is still frequently seen in Uzbekistan, Eastern Europe. This is the first study undertaken to estimate the prevalence and factors associated with deficiency of vitamin D in infants in this region of Eastern Europe.Methods. Information was obtained by parental questionnaires for 474 infants aged 5–61 weeks attending rural out‐patient clinics in Samarkand. Blood was assayed for 25‐OHD and ferritin concentration.Results. Prevalence of vitamin D deficiency (25‐OHD <30 nmol l−1) was 78.7% and was significantly associated with continued breastfeeding (p<0.05), lack of vitamin supplementation (p<0.05), residence in a rural area (p<0.05) and reduced time spent outdoors (p<0.05). Maternal characteristics did not differ between mothers of infants with and without biochemical rickets. Possible causes are a combination of factors including vitamin D deficiency in pregnancy, prolonged breastfeeding without supplementation, a vitamin D poor diet and traditional avoidance of sunlight in the first year of life. Over 40% of the children had low ferritin values. Most children with low ferritin values were also vitamin D deficient (90.3%). Almost 10% of infants had persistently low 25‐OHD levels following 6 weeks of therapy (4000 IU/day).Conclusion. There is an urgent need for adherence to clear recommendations for primary and secondary prevention of this major clinical and public health problem in Samarkand infants.