Thyroid profile modifications during oral hormone replacement therapy in postmenopausal women

Clinical observation of menopause hormone therapy in postmenopausal women with euthyroid and mild subclinical hypothyroidism

BACKGROUND

To evaluate the endocrine hormone and metabolic indices in postmenopausal women with euthyroid and mild subclinical hypothyroidism after menopause hormone therapy (MHT).

METHODS

A retrospective study of 587 postmenopausal women receiving MHT was conducted. Median (25-75th percentile) age was 52 (49-54) years. According to thyroid stimulating hormone (TSH) levels at initial diagnosis, the patients were divided into three groups: I (euthyroid with low normal TSH range, n = 460), II (euthyroid with upper normal TSH range, n = 106) and III (mild subclinical hypothyroidism, n = 21). After a continuous oral MHT regimen using the same estradiol potency for 6-18 month cycles, serum endocrine hormone and metabolic indices were reassessed.

RESULTS

Compared with baseline, serum TSH levels in groups I and II significantly changed but all values were within the normal range. No significant difference was observed in serum TSH levels in group III. After treatment, all serum free tri-iodothyronine and free thyroxine levels were within the normal range. Serum total cholesterol, triglyceride, fasting plasma glucose, fasting insulin levels and homeostasis model assessment of insulin resistance index had significantly decreased in group I. There were no significant differences in all observed lipid and glucose parameters in group III, before and after treatment.

CONCLUSION

MHT did not affect thyroid function in postmenopausal women with euthyroid and mild subclinical hypothyroidism. MHT led to an improvement in lipid and glucose indicators in euthyroid women with low normal TSH range.

Effects of oral contraceptives on thyroid function and vice versa

BACKGROUND

Thyroid gland dysfunction represents an epidemiologically relevant disease in the female gender, where treatment with oral contraceptives (OCs) is frequently prescribed. Although OCs are able to impact the thyroid gland function, scanty data have been released on this matter so far.

AIM

The aim of this article was to review how hormonal OCs, including estrogen- or progesterone-only containing medications, interact with the hepatic production of thyroid-binding globulin (TBG) and, consequently, their effects on serum levels of thyroxine (T4) and triiodothyronine (T3). We also reviewed the effect of Levo-T4 (LT4) administration in women taking OCs and how they influence the thyroid function in both euthyroid women and in those receiving LT4.

REVIEW

The estrogenic component of the pills is capable of increasing various liver proteins, such as TBG, sex hormone-binding protein (SHBG) and coagulation factors. On the other hand, the role of progestogens is to modulate estrogen-dependent effects mainly through their anti-androgenic action. In fact, a reduction in the effects of androgens is useful to keep the thromboembolic and cardiovascular risks low, whereas OCs increase it especially in women with subclinical hypothyroidism or in those treated with LT4. Accordingly, subclinical hypothyroidism is known to be associated with a higher mean platelet volume than normal and this increases cardiovascular risk due to platelet hyperactivity caused by incomplete thrombocytopoietic maturation.

Thyroid hormones affect recovery from depression during antidepressant treatment

AIMS

The aim of the present study was to evaluate whether thyroid hormonal changes during menopause may affect the development and the course of major depressive disorder.

METHODS

Thirty-nine female patients (n = 17 in pre-menopause; n = 22 in post-menopause) with major depressive disorder based on Diagnostic Statistical Manual of Mental Disorders (4th edition) criteria and who were euthyroid and not on hormonal replacement therapy, participated in a prospective, 6-week, open-label naturalistic study. The Hamilton Depression Rating Scale-17 item, the Montgomery-Asberg Depression Rating Scale, the Clinical Global Impression scale and the Cognitive Failure Questionnaire were administered at baseline, week 1, week 3, and week 6. Levels of thyroid stimulating hormone, total thyroxine and total triiodothyronine were collected at baseline visit.

RESULTS

In the whole sample, particularly in pre-menopausal women, levels of thyroid stimulating hormone-potential markers of subclinical hypothyroidism were correlated with those of less severe but more resistant depressive form. Conversely, total thyroxine levels were correlated with a more severe depression, but high levels of this hormone favored the response to antidepressants. Overall, a diagnosis of subclinical hypothyroidism was associated with a poor response to antidepressant treatment. Finally, total triiodothyronine levels were associated with better cognitive functioning, though they did not influence improvement occurring with recovery.

CONCLUSIONS

Our study suggests that thyroid hormones may have an impact on severity and efficacy of antidepressant treatment. However, our result should be considered with caution and merely as a suggestion due to some methodological limitations. Hence further studies are required to better ascertain the role of thyroid hormones in depression after menopause.

Plasma leptin in female athletes: relationship with body fat, reproductive, nutritional, and endocrine factors

The relationship of leptin to thyroid and sex hormones, insulin, energy intake, exercise energy expenditure, and reproductive function was assessed in 39 female athletes. They comprised elite athletes who were either amenorrheic (EAA; n = 5) or cyclic (ECA; n = 8) and recreationally active women who were either cyclic (RCA; n = 13) or taking oral contraceptives (ROC; n = 13). Leptin was significantly lower in EAA (1.7 +/- 0.2 ng/ml) than in ECA (2.9 +/- 0.3 ng/ml), RCA (5.8 +/- 0.9 ng/ml), and ROC (7.4 +/- 1.3 ng/ml). Hypoleptinemia in EAA was paralleled by reductions (P < 0.05) in caloric intake, insulin, estradiol, and thyroid hormones. Leptin increased by 40-46% (P < 0.05) in the luteal phase of the menstrual cycle in RCA and ECA. Plasma leptin was similar in the placebo and active pill phases in ROC despite a significant increase in ethinylestradiol. Leptin correlated (P < 0.05) with triiodothyronine and insulin but not with estrogen, energy intake, or exercise energy expenditure. These data suggest that in female athletes 1) leptin may be a metabolic signal that provides a link between adipose tissue, energy availability, and the reproductive axis and 2) sex hormones do not directly regulate leptin secretion.