Prevalence and factors influencing sub-optimal serum levels of 25-hydroxyvitamin D among children with sickle cell anaemia in south-west Nigeria

Abstract

Background: Sub-optimal levels of vitamin D worsens morbidity in sickle cell anaemia (SCA). Increased frequency of pain episodes and haemolysis have been linked with the deficiency and or insufficiency of vitamin D among individuals with SCA. In Nigeria, the country with the highest SCA burden, data on the prevalence and risk factors for sub-optimal vitamin D in SCA is scanty. Objectives: The objectives of this study were to determine the prevalence of depressed vitamin D and examine the influence of sociodemographic characteristics and anthropometric parameters on the serum levels of 25-hydroxyvitamin D (25-OHD) among Nigerian children with SCA. Methods: In this cross-sectional comparative study, serum 25-OHD levels of 95 children with SCA and 75 age- and gender-matched haemoglobin AA control were quantified by high performance liquid chromatography over a six-month period. Results: A higher proportion of children with SCA had sub-optimal 25-OHD compared with the controls: 12.6% vs. 2.7%, p = 0.013, 95% CI = 1.1–24.4. The mean serum 25-OHD of the children with SCA was also significantly lower (41.8 ± 9.8ng/mL vs. 45.2 ±8.1ng/mL, p = 0.017, 95% CI = 1.6 – 6.1). Serum 25-OHD was not related to age, sex, social class, presence of underweight, overweight/obesity and stunting in both bivariate and multivariate analyses. Conclusion: The prevalence of low serum vitamin D was higher among SCA patients than the matched controls. The serum level was not influenced by their sociodemographic and nutritional status.

Keywords

• 25-hydroxyvitamin D
• Children
• Cholecalciferol
• Nigerian
• Sickle cell anaemia
• Prevalence