A Clinical Study on Female Bipolar Patients and the Association of Hypothyroidism and Rapid-cycling States

But only four studies documented a greater prevalence of hypothyroidism in rapid-cycling bipolar disorder patients.Interpretation of the results was complicated by the fact that not all studies took into account relevant differences in age and duration of lithium treatment.Although the most common psychiatric disorder in hypothyroidism is depressive disorder but there are few studies that have reported the association of mania with hypothyroidism.5,6 Thompson et al., in a prospective cohort study, found that there is an increase in bipolar disorder or depressive disorder in hospitalized patients with hypothyroidism.7 IntroductIonThere has been a remarkable consistency in the finding that women are more likely than men to experience a rapid-cycling phase to their bipolar illness. 1 Rapid-cycling is said to occur when a patient experiences at least four distinct mood episodes during a 12-month period.Different studies prove that female bipolar patients are more vulnerable to rapid-cycling type of bipolar disorder.Pooled data analysis of 10 studies by Tondo and Baldessarini reported the sex distribution of patients with rapid-cycling and nonrapid-cycling bipolar disorder.Among the 2057 patients included, women on average accounted for 71.7% of the cases of rapid-cycling, representing a 2.5-fold difference over men.Of interest, rapid cycling occurred at 29.6% of all female bipolar patients, and 16.5% of all male bipolar patients.2 It has been observed that hypothalamic-pituitary-thyroid (HPT) axis dysfunction has an impact on the pathophysiology of bipolar affective disorder (BPAD).And hypothyroidism is the most commonly encountered HPT axis dysfunction.Beuer et al. reported that the prevalence of thyroid disease in BPAD is much higher in female than male patients with bipolar disorder.3 Higher rates of hypothyroidism were found to be associated with high rates of rapid-cycling bipolar disorder in several studies, along with an association of more frequent use of antidepressants and the influence of menstrual cycle on mood in females.Leibenluft 4 analyzed eight studies that examined whether hypothyroidism was more common among rapid-cycling than nonrapid-cycling bipolar patients.