Rapid cycling bipolar affective disorder: lack of relation to hypothyroidism.
Thyroid indices were measured after an extended period of medication-free evaluation averaging 6 weeks in 67 consecutively admitted patients with bipolar illness. Thyroid hormone levels -- thyroxine (T4), free T4 and triiodothyronine (T3) -- were not significantly different in the 31 rapid cyclers (> or = 4 affective episodes/year) than in 36 non-rapid cyclers. Analysis of covariance indicated a non-significant trend relation between higher T4 and a greater number of affective episodes in the year prior to admission and male gender when age was covaried. Several previous reports, primarily in medicated subjects, have suggested a link between rapid cycling patients and decreased peripheral thyroid indices (low hormone levels and elevated TSH), but now the majority of studies do not support such a relation. Among those in the literature, this study includes patients studied for the longest time off medications and further suggests that the commonly-cited relation between subclinical hypothyroidism and rapid cycling bipolar illness be reevaluated.
Post
R M
RM
Biological Psychiatry Branch, National Institute of Mental Health, Bethesda, MD 20892, USA.
Kramlinger
K G
KG
Joffe
R T
RT
Roy-Byrne
P P
PP
Rosoff
A
A
Frye
M A
MA
Huggins
T
T
D000328:Adult; D001714:Bipolar Disorder / Q000175:diagnosis / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000175:diagnosis / Q000503:physiopathology*; D008297:Male; D012016:Reference Values; D013960:Thyroid Function Tests; D013961:Thyroid Gland / Q000503:physiopathology; D013963:Thyroid Hormones / Q000097:blood*; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
D013963:Thyroid Hormones; D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine