Prevalence and Risk Factors of Hypovitaminosis D in Nigerian Children with Sickle Cell Anaemia

Abstract

Background: Vitamin D deficiency (VDD) has been linked to some acute and chronic bone disorders that commonly complicate sickle cell anaemia (SCA) in children. Some of these bone diseases include chronic pain, reduced bone density and fractures. Despite Nigeria having the highest number of children with SCA in the world, there is a paucity of data on vitamin D status and the associated risk factors in affected children. Objective: To determine the prevalence and risk factors for hypovitaminosis D in children with sickle cell anaemia in steady-state. Methods: A total of 174 children with sickle cell anaemia aged one to eighteen years were recruited at the Sickle Cell Foundation Centre, Lagos. Baseline sociodemographic, clinical, anthropometric and laboratory parameters (serum 25-hydroxyvitamin D, corrected serum calcium and alkaline phosphatase) were recorded. Results: The prevalence of vitamin D insufficiency and deficiency were 12.6 % and 72.5% respectively. Children below six years of age were less likely to have hypovitaminosis D compared to the older age groups (p = 0.017). The mean serum corrected calcium was lowest in subjects with vitamin D deficiency (p >0.001). Age and hypocalcaemia are independent predictors of hypovitaminosis D. Conclusion: There is a high prevalence of vitamin D deficiency among children with sickle cell anaemia. Children aged below six years and with those with hypocalcaemia had higher odds of hypovitaminosis D.