BACKGROUND: There is debate whether patients with rapid-cycling bipolar disorder (BD) are predisposed to thyroid axis abnormalities and whether this may contribute to development of rapid mood shifts. Using lithium carbonate as a challenge to the hypothalamic-pituitary-thyroid (HPT) system, we determined whether patients with rapid-cycling BD are sensitive to the "antithyroid" properties of lithium. METHODS: We studied the response to thyrotropin-releasing hormone (TRH) of HPT system hormones in 20 medication-free patients with rapid-cycling BD and compared these measurements with those of 20 healthy age- and gender-matched control subjects. The same measurements were repeated after both groups had received lithium carbonate for 4 weeks in sufficient doses to maintain blood levels between.7-1.2 mEq/L. RESULTS: At baseline, the results of thyroid function tests, including the TRH challenge test, did not differ between patients and control subjects. After treatment with lithium, serum concentrations of thyroxine significantly decreased, whereas basal thyrotropin (TSH) and DeltaTSH(max) significantly increased in both patients and control subjects; however, patients had significantly higher DeltaTSH(max) after TRH stimulation. More patients than control subjects developed laboratory evidence consistent with grade III hypothyroidism after lithium treatment. CONCLUSIONS: Rapid-cycling BD is associated with a latent hypofunction of the HPT system. This dysfunction becomes manifest with short-term lithium challenge.
BACKGROUND: There is debate whether patients with rapid-cycling bipolar disorder (BD) are predisposed to thyroid axis abnormalities and whether this may contribute to development of rapid mood shifts. Using lithium carbonate as a challenge to the hypothalamic-pituitary-thyroid (HPT) system, we determined whether patients with rapid-cycling BD are sensitive to the "antithyroid" properties of lithium. METHODS: We studied the response to thyrotropin-releasing hormone (TRH) of HPT system hormones in 20 medication-free patients with rapid-cycling BD and compared these measurements with those of 20 healthy age- and gender-matched control subjects. The same measurements were repeated after both groups had received lithium carbonate for 4 weeks in sufficient doses to maintain blood levels between.7-1.2 mEq/L. RESULTS: At baseline, the results of thyroid function tests, including the TRH challenge test, did not differ between patients and control subjects. After treatment with lithium, serum concentrations of thyroxine significantly decreased, whereas basal thyrotropin (TSH) and DeltaTSH(max) significantly increased in both patients and control subjects; however, patients had significantly higher DeltaTSH(max) after TRH stimulation. More patients than control subjects developed laboratory evidence consistent with grade III hypothyroidism after lithium treatment. CONCLUSIONS: Rapid-cycling BD is associated with a latent hypofunction of the HPT system. This dysfunction becomes manifest with short-term lithium challenge.
Authors: Meritxell Tost; José Antonio Monreal; Antonio Armario; Juan David Barbero; Jesús Cobo; Clemente García-Rizo; Miquel Bioque; Judith Usall; Elena Huerta-Ramos; Virginia Soria; Javier Labad Journal: Clin Drug Investig Date: 2020-01 Impact factor: 2.859
Authors: Konstantinos N Fountoulakis; Lakshmi Yatham; Heinz Grunze; Eduard Vieta; Allan Young; Pierre Blier; Siegfried Kasper; Hans Jurgen Moeller Journal: Int J Neuropsychopharmacol Date: 2017-02-01 Impact factor: 5.176
Authors: Patricia D Walshaw; Laszlo Gyulai; Michael Bauer; Mark S Bauer; Brian Calimlim; Catherine A Sugar; Peter C Whybrow Journal: Bipolar Disord Date: 2018-06-04 Impact factor: 6.744