Vitamin D, Testosterone, and Thyroid Status in Young Men at Different Seasons

Abstract

There are evidences that seasonal fluctuations in vitamin D levels coincide with annual rhythms of testosterone levels, and hypothyroidism may be a predictor of hypoandrogenism. The aim of the study was to establish the levels of vitamin D (vit. D), testosterone (T), thyroid stimulating hormone (TSH) and free thyroxine (T4f) in young people with pathospermia and normospermia in the spring-summer and autumn-winter periods. Materials and methods. The data of 58 men aged 23-44 years, who are in a sterile marriage, were analyzed: 24 were examined in the spring-summer period, 34 - in the autumn-winter period. BMI, levels of T, TSH, T4fandvit. Dwere investigated. Results. In the general group of men, the frequency of D - hypovitaminosis was higher in those examined in the autumn-winter period. Vit D levels were significantly lower with pathospermia than with normospermia. BMI did not significantly affect the level of vit.D in the blood.A direct correlation between vit. D and T in men with patho- and normospermiahas not been established, although such a correlation took place in the general group of the surveyed. The average TSH values ​​in the group examined in the spring-summer period did not significantly differ in the group with patho- and normospermia, and in those examined in the autumn-winter period, against the background of pathospermia, there was a decrease in T4f values ​​and an increase in TSH. 13.6% of this subgroup had laboratory signs of subclinical hypothyroidism. Conclusions: In men of the general group, without taking into account the state of the spermatogenic function of the testicles, examined in the autumn-winter period, there is a significant increase in the frequency of D-hypovitaminosis compared with a similar group of men in whom the level of vitamin D blood was determined in the spring-summer period. Regardless of the examination period, patients with pathospermia show a decrease in the average levels of vitamin D and testosterone compared to men with normal semen parameters. The frequency of vitamin D deficiency in patients with pathospermia significantly increases in the autumn-winter period. Disorders of spermatogenesis in men can be associated with the hypofunctional state of the thyroid gland against the background of the existing deficiency of vitamin D in the autumn-winter period.