RAPID-CYCLING BIPOLAR AFFECTIVE-DISORDER - LACK OF RELATION TO HYPOTHYROIDISM

Thyroid indices were measured after an extended period of medication-f ree evaluation averaging 6 weeks in 67 consecutively admitted patients with bipolar illness. Thyroid hormone levels - thyroxine (T-4), free T-4 and triiodothyronine (T-3) - were not significantly different in t he 31 rapid cyclers (greater than or equal to 4 affective episodes/yea r) than in 36 non-rapid cyclers. Analysis of covariance indicated a no n-significant trend relation between higher T-4 and a greater number o f affective episodes in the year prior to admission and male gender wh en age was covaried. Several previous reports, primarily in medicated subjects, have suggested a link between rapid cycling patients and dec reased peripheral thyroid indices (low hormone levels and elevated TSH ), but now the majority of studies do not support such a relation. Amo ng those in the literature, this study includes patients studied for t he longest time off medications and further suggests that the commonly -cited relation between subclinical hypothyroidism and rapid cycling b ipolar illness be reevaluated. (C) 1997 Elsevier Science Ireland Ltd.