Evaluation of 25-Hydroxy-Vitamin D Levels in Hypothyroid Patients Receiving Levothyroxine Sodium Therapy

Aim: It was aimed to evaluate 25-hydroxy-vitamin D (25 (OH) D) levels in hypothyroid patients with levothyroxine sodium (LT4) therapy and euthyroidism. Material and Method: 116 patients with hypothyroidism with LT4 treatment and euthyroidism in the Internal Medicine Policlinic, as control group, 110 patients with similar age and sex without hypothyroidism were enrolled to study. Patients were recorded in terms of age, sex, LT4 drug doses and free T4, TSH, 25 (OH) D, BUN, Creatinine, Calcium (Ca), Phosphorus (P), Albumin values. There was a significant difference between the groups. Results: In study, 25 (OH) D level was significantly lower in patients with hypothyroid patients receiving LT4 therapy and euthyroidism than in control group (p<0.001). In the patient group there was no significant relationship between the 25 (OH) D levels and the LT4 drug doses received by the patients (r=0.060 p=0.52). There was no relationship in the 25 (OH) D levels between the women and the men (p=0.75). Conclusion: It was concluded that 25 (OH) D levels may be lower in hypothyroid patients treated with LT4 and that low vitamin D levels may be involved in the etiology of hypothyroidism and that active vitamin D supplementation in addition to LT4 therapy with hypothyroidism may be beneficial