Sexual medicine specialists should be aware of the links between thyroid disease and sexual problems, especially since treatment of thyroid disorders often improves sexual function, researchers say.

The study, published in July as an article in press for Sexual Medicine Reviews, discussed sexual dysfunction in the context of two thyroid disorders:

• Hypothyroidism – an underactive thyroid, which does not produce adequate amounts of thyroid hormone. Common symptoms include weight gain, fatigue, constipation, and cold intolerance.
• Hyperthyroidism – an overactive thyroid, which produces excess amounts of thyroid hormone. Common symptoms include increased appetite and weight gain, heat intolerance, and nervousness.

For their review, the researchers examined 12 studies that discussed thyroid disease and sexual dysfunction in both males and females.

They found that the among patients with hypothyroidism, 59% to 63% of men and 22% to 46% of women experienced sexual difficulties. For patients with hyperthyroidism, the ranges were 48% to 77% for men and 44% to 60% for women.

Erectile dysfunction (ED) and ejaculatory disorders were common problems for men with both types of thyroid disease. Delayed ejaculation was associated more with hypothyroidism, while premature ejaculation was linked to hyperthyroidism.

For the women, both hypothyroidism and hyperthyroidism were associated with low desire, poor arousal and lubrication, orgasm difficulties, low sexual satisfaction, and pain during intercourse.

The authors suggested possible mechanisms:

• Hormonal disruptions. Both hypothyroidism and hyperthyroidism may interfere with hormones. For example, lower concentrations of total and free testosterone were found in men with hypothyroidism. Among men with hyperthyroidism, increases in sex hormone-binding globulin lead to “relative hyper-estrogenism,” resulting in decreased amounts of bioavailable testosterone.

For women with hypothyroidism, low circulating thyroid concentration “is the most important factor driving [sexual dysfunction],” the authors said.

Hypothyroidism is also associated with hyper-prolactinemia (high levels of prolactin) in both men and women, which can lead to hypoactive sexual desire disorder (HSDD).

• Indirect effects. Many patients with hypothyroidism feel fatigued or depressed. They may also be more likely to have metabolic syndrome, often a precursor to cardiovascular disease and type 2 diabetes. All of these factors can contribute to sexual dysfunction.

Depression and anxiety associated with hyperthyroidism may influence sexual function as well.

Treatment for both thyroid diseases, such as replacement therapy for patients with hypothyroidism and radioactive iodine, medications, or thyroidectomy for those with hyperthyroidism, brought about “dramatic resolution” of sexual function, the authors wrote.

They expressed concern that sexual dysfunction among thyroid disease patients “receives little attention in clinical practice” and noted the small sample sizes in many of the studies they reviewed.

“Unfortunately, well-designed studies that describe the prevalence, pathophysiology, and outcomes of patients with sexual dysfunction in the setting of thyroid disease are severely lacking,” the authors explained, adding that sexual problems are often considered low-priority in patients with thyroid disease. Patients may be reluctant to discuss sexual problems, too.

Resources

• “The Impact of Thyroid Disease on Sexual Dysfunction in Men and Women”
  Gabrielson, Andrew T., BA, et al.
  (Full-text article in press. Published online: July 26, 2018)
  https://www.smr.jsexmed.org/article/S2050-0521(18)30059-3/fulltext