Differences in thyroid function between bipolar manic and mixed states.
BACKGROUND
High rates of thyroid axis abnormalities have been reported in most studies of patients with rapid-cycling bipolar disorder. Mixed states share similarities with rapid-cycling, including close temporal occurrence of manic and depressive symptoms, predominance in women, poor outcome, and less robust response to lithium compared with pure mania; however, thyroid axis abnormalities have not been well studied in mixed mania.


METHODS
To test the hypothesis that mixed states are associated with a higher prevalence of hypothyroidism than pure mania, immunoreactive triiodothyronine (T3), thyroxine (T4), and thyroid-stimulating hormone (TSH) concentrations were determined from serum obtained at the time of admission in 37 consecutive patients with DSM-III-R bipolar disorder, manic or mixed.


RESULTS
The mean TSH concentration was significantly higher, and the mean T4 concentration was significantly lower in patients with mixed mania compared with pure mania. There were no significant differences in T3 concentration or in previous lithium exposure.


CONCLUSIONS
These findings suggest thyroid axis dysfunction is more common in bipolar mixed than in bipolar manic patients.
Chang
K D
KD
Department of Psychiatry, University of Cincinnati College of Medicine, Ohio 45267-0559, USA.
Keck
P E
PE
Stanton
S P
SP
McElroy
S L
SL
Strakowski
S M
SM
Geracioti
T D
TD
D000328:Adult; D018692:Antimanic Agents / Q000627:therapeutic use; D001714:Bipolar Disorder / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D005260:Female; D006801:Humans; D016651:Lithium Carbonate / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D013960:Thyroid Function Tests; D013963:Thyroid Hormones / Q000097:blood*
D018692:Antimanic Agents; D013963:Thyroid Hormones; D016651:Lithium Carbonate