Sher L, Rosenthal NE, Wehr TA.
Section on Biological Rhythms, National Institute of Mental Health, Bethesda, MD 20892-1390, USA.
J Affect Disord. 1999 Dec;56(2-3):195-9.
Seasonal affective disorder (SAD) is characterized by recurrent episodes of depression in the fall and winter that alternate with nondepressed periods in the spring and summer. Because some symptoms of SAD, such as decreased energy and weight gain, also occur in hypothyroidism, it is possible that individuals with SAD have a subtle decrease in thyroid function. To test this hypothesis, we studied blood levels of free thyroxine (T4) and thyroid-stimulating hormone (TSH) in SAD patients and matched controls in the winter.
Mood Disorders