The association between vitamin D and Hashimoto’s thyroiditis
Cevdet Guzelsagaltici, Gulseren Pamuk, Umit Cavdar, Alperen Ihtiyar, Figen Narin, Baris Onder Pamuk
Hashimoto’s thyroiditis is probably the most common autoimmune disease treated in endocrinology clinics. It is still contraversial whether vitamin D deficiency is a cause or result of Hashimoto’s throiditis. However pleiotropic effects of vitamin D have been described recently in many studies that its deficiency could be a predisposing factor for autoimmune diseases. This clinical research aims to show the relationship between vitamin D deficiency and Hashimoto thyroiditis. One hundred twenty six participants who admitted to family medicine clinics in year 2017 during a 6 months period of time at Izmir Katip Celebi University Hospital in Turkey were included in our cross sectional study. Openepi sample size calculator predicted 95% of confidence interval, 80% of power and 5% of tolerence with consisting a number of 38 individuals in each group. Patients were grouped as previously diagnosed Hashimoto’s thyroiditis, newly diagnosed Hashimoto’s thyroiditis and healthy individuals. After supplying reserved participants which consist of 10% of the total, 42 individuals recruited in each group. Vitamin D levels were significantly lower in both previously diagnosed Hashimoto and newly diagnosed Hashimoto groups than control group with values of 12.62ng/dl, 11.76ng/dl and 15.03ng/dl respectively (p <0.05). Vitamin D insufficiency found to be correlated with TSH, fT4, anti-TPO, anti-Tg, kreatin, PTH levels, BMI, smoking and female gender (p <0.05). Multiple regression analysis of these parameters via retrospective elimination method showed that vitamin D is negatively correlated with BMI and anti-Tg. On the other a positive correlation with fT4 was also shown in the study. Vitamin D deficiency may be a predisposing factor for Hashimoto’s disease.
Key words: Vitamin D deficiency, hashimoto disease, thyroiditis, autoimmune, antibodies