Endocrine Abstracts

Background

Today thyroid diseases occupy the first place among all endocrine pathologies and remain one of the most difficult problems. The prevalence of subclinical hypothyroidism, according to various data, is 4–15%. The category of women of reproductive age deserves special attention, as thyroid dysfunction affects a woman’s fertility and pregnancy. Vitamin D deficiency in the population remains a global problem. The purpose of the study is to determine the level of 25-hydroxy vitamin D3 [25 (OH) D3] in women with subclinical hypothyroidism and investigate the relationship between hypothyroidism and vitamin D deficiency.

Materials and methods

We examined 90 women with subclinical hypothyroidism, TPO-Ab + and 25 healthy women, the average age of women with subclinical hypothyroidism was 25.8 ± 1.6 years, of women in the control group was 24.4 ± 1.4 years. The levels of TSH, FT4, FT3, TPO-Ab and 25 (OH) D3 was determined. 25 (OH) D3 was measured by radioimmunoassay, the level of TSH, FT4, FT3 was measured by the immunochemical method.

Results

The level of 25 (OH) D3 was 18.24 ± 1.24 ng/ml (at a rate of 30–50 ng/ml) in women with subclinical hypothyroidism and 29.28 ± 1.02 ng/ml in women of the control group. In all women with subclinical hypothyroidism, vitamin D levels were defined as insufficient or deficient (vitamin D deficiency is detected at less than 20 ng/ml, vitamin D insufficiency is detected at 20–29.9 ng/ml), their TSH level was 5, 7 ± 0.84, FT4- 14.6 ± 1.12, FT3–3.9 ± 0.82, TPO-Ab - 384 ± 2, 46 (P < 0.001). It was investigated that the level of 25 (OH) D3 was inversely correlated with TSH levels and TPO-Ab in women with subclinical hypothyroidism.

Conclusions

We investigated that low levels of 25 (OH) D3 were present in all women with subclinical hypothyroidism. An inverse correlation occurred between a decrease in the level of 25 (OH) D3 and an increase in the level of thyroid-stimulating hormone (r = –0.39, P < 0.05), between a decrease in the level of 25 (OH) D3 and an increase in the level TPO-Ab (r = –0.37, P < 0.05) In order to improve the compensation of hypothyroidism in women of reproductive age, it is recommended to add vitamin D supplements to the main treatment.