Background: The association between serum 25-Hydroxy vitamin D (25-OH vitamin D) level in hypothyroid subjects with and without thyroidperoxidase (TPO) antibodies is controversial. There is increasing evidence that 25-OH vitamin D level is associated with autoimmune diseases.
Objectives: To assess serum 25-OH vitamin D levels among hypothyroidism Sudanese patients with and without thyroid peroxidase (TPO) antibodies.
Materials and methods: analytical cross-sectional conducted at The Center for Diabetes and Endocrinology in Khartoum from February to October 2020. Sixty subjects with hypothyroidism were recruited from the follow-up clinic. Other sixty age and sex-matched subjects were selected as control. Thyroid function tests (TSH, FT4 and FT3) were measured using TOSOH AIA 360 system analyzer, serum 25-OH vitamin D level was measured using semiautomatic I-Chroma-II reader and thyroid peroxidase antibodies (TPO antibodies) were measured in both cases and controls using ELISA technique. The results were analyzed using SPSS version 21.
Result: TSH was significantly increased in both TPO antibodies positive and TPO antibodies negative hypothyroid subjects than the control (22.3±4.44), (10.5±2.55) (3.42±0.75), respectively, with P-value 0.000. Level of 25-OH Vitamin D was lower among hypothyroid subjects than the control. Subjects with positive TPO antibody had lower 25-OH vitamin D levels than the TPO-antibody negative subjects compared to control (7.45±4.50̽) (10.5±7.18) (48.8±10.0), respectively, with P-value 0.000. Females 46 (77%) were more than males 14(23%).
Conclusion: 25-OH vitamin D level was low in patients with hypothyroidism. Subjects with positive TPO-antibodies had lower serum 25-OH vitamin D compared to TPO-antibody negative subjects.