Hypovitaminosis D and iron deficiency in children: A new approach to its unexplained relationship with osteoarticular pain

Abstract

Abstract Purpose The purpose of this study was to determine the association between growing pain and arthralgia and vitamin D and iron deficiency in children. Methods This prospective, observational, case-control study were recruited 89 children (47 patients and 42 controls) during January 2019 to September 2021. In a first blood biochemistry, children with low vitamin D levels were treated for 8 weeks and children with low ferritin levels were treated with iron supplementation between 4–5 mg/kg/day, for 12 weeks. A second blood biochemistry was carried out after treatment. Data on arthralgias, bone and mixed pain were collected before and after treatment. Results Before treatment, the average serum 25-hydroxyvitamin D (25-OH D) level was significantly lower in patients with hypovitaminosis than in the control group (24.96 (± 5.9) vs. 32.00 (± 11.2) respectively) (p = 0.008). After treatment, 95% of the patients reported pain relief and vitamin D mean concentration was restored in hypovitaminosis group (above 30ng/ml) and did not differ significantly from controls (33.2 (± 6.1) vs. 32.00 (± 11.2) respectively) (p = 0.644). The association between iron metabolism and arthralgia was neither significant nor conclusive for iron (p = 0.054) and no significant for ferritin and pain (p = 0.555). After treatment, 19 (95%) patients reported pain remission, the only one not recovered suffering from bone (growing) pain (p < 0.001). Conclusions An association between decreased vitamin D levels and osteoarticular pain was found. Also, osteoarticular pain remitted after treatment to restore suitable vitamin D level.