“…Hypothyroidism has been shown to be associated with refractory depression (Joffe and Levitt, 1992;Howland, 1993), to be more prevalent in chronic than in acute depression, and also to be related to a rapid cycling course and poor treatment response in patients with bipolar disorder (Bauer et al, 1990;Howland, 1995, Lossen, 1986, Oomen et al, 1996. On the other hand, other reports indicate that hyperthyroidism may be related to the occurrence of manic episodes (Corn et al, 1983;Lee et al, 1991;Joyce, 1991;Walter-Ryan et al, 1986). While there are no reports in the literature about a clear relationship between the type of thyroid dysfunction and the type of affective episode, clinical experience suggests that thyroid hyperfunction is more often associated with mania than with depression.…”