The androgen hormone testosterone is secreted in the adrenal glands and ovaries in women and in the adrenal glands and testes in men. The hormone is closely related to optimal sexual performance in both men and women. Bipolar disorder, which is associated with depression and mania, may worsen due to an imbalance in testosterone levels, particularly in older men.
Bipolar disorder is a mental illness characterized by periods of depression and at least one episode of mania. During the depressive episodes, individuals typically experience sadness, gloominess, worthlessness and a loss of interest in activities they normally find stimulating. Mania is associated with increased energy but often of an unpleasant kind that can coincide with irritability and aggression. Manic people furthermore are often extremely motivated but the motivation often leads to bad decision making rather than a state of increased productivity.
Low Testosterone and Depression
Low testosterone can cause clinical depression, particularly in older men. Testosterone may not be a direct cause of the chemical imbalance underlying depression. Low levels of this hormone, however, gives rise to a decreased sex drive, irritability and a lack of energy. These negative mental and physical factors may lead to an increased breakdown of serotonin in the brain, a state directly linked to depression.
High Testosterone and Mania
High testosterone levels, on the other hand, are more likely to give rise to symptoms of mania. Excessive amounts of available testosterone in the bloodstream can give rise to irritability, aggressiveness, vindictiveness and a desire to act. The extreme energy levels that can accompany high testosterone levels can also distort rational thought processes and lead to irrational decision making. All of these are symptoms that also accompany states of clinically diagnosed mania.
Testosterone and Bipolar Disorder
Though there is no direct scientific evidence to suggest that fluctuating testosterone levels have any bearing on clinically diagnosed bipolar disorder, an imbalance in testosterone could be a factor in bipolar disorder. Cancer in the testes, ovaries or adrenal glands can lead to severe fluctuations in testosterone levels. An overactive thyroid gland can also cause hormonal fluctuations. An excess secretion of thyroid hormones increases testosterone levels but it also increases the levels of sex hormone-binding globulin, which binds testosterone and makes it unavailable for binding elsewhere in the body. Most cases of bipolar disorder, however, have different underlying causes.