Vitamin D status among infants attending Reproductive and Child Health Centre in Arusha, Tanzania; A cross-sectional study

Abstract Background: Globally there is a high burden of low serum vitamin D levels, with children being more at risk, due to low intake in breastmilk, few available foods and inadequate cutaneous synthesis of vitamin D. Even in countries with abundant sunshine, Vitamin D deficiency (VDD) remains a problem. The classical clinical effect of severe vitamin D deficiency is rickets. VDD is common in developing countries and may affect developmental outcomes of children. This study aimed to determine the prevalence and factors associated with vitamin D deficiency among infants attending the Reproductive and Child Health Clinic (RCH), in Arusha, Tanzania.Methods: This was a cross-sectional study of infants aged 6 weeks to 12 months attending RCH clinic at Arusha Lutheran Medical Centre (ALMC). We enrolled 304 infants from November 2018 to January 2019 after consent. A pre-coded questionnaire was used to collect data on sociodemographic characteristics of the infants. Physical examination was done for anthropometric measures and signs of rickets. Serum was drawn for assessment of 25-hydroxyvitamin D (25(OH) D),calcium, phosphorus, alkaline phosphate was assessed. Vitamin D deficiency was defined as 25(OH)D less than 20ng/ml. Multivariate analysis was done to determine factors associated with VDD. Statistical analysis was performed using STATA 14 version. P- value < 0.05 was significant. Results: A total of 67/ 304 infants had vitamin D deficiency. Another 50(16.5%) were found to have insufficiency level of vitamin D. Only 187(61.5%) had adequate vitamin D. Signs of rickets were observed in 11(3.6%) and hypocalcemia in 33(10.9%) infants. Factors independently associated with VDD include age < 6 months Adjusted Odds Ratio (AOR) 1.56 (95% CI 1.19-4.0) p value < 0.026, presence of signs of rickets and hypocalcemia p value <0.001 and <0.002 respectively. Conclusion and Recommendation: A high prevalence of VDD (22%) was observed among infants attending RCH clinic in Arusha Tanzania. Age <6 months and the presence of the clinical sign of rickets were associated with VDD. Clinicians should actively assess for VDD and vitamin D supplementation with special emphasis infants <6 months should be implemented.