Improvement in depression with oestrogen treatment in women with schizophrenia

Women with schizophrenia are often noted to suffer with comorbid depression. Many studies have shown associations between fluctuating oestrogen levels in the brain and mental illness. This study investigates the effect of oestradiol treatment on comorbid depressive symptoms in women with schizophrenia. This study is an 8-week, three-arm, double-blind, randomised-controlled trial. The 180 female participants were aged between 18 and 45, with schizophrenia and ongoing symptoms of psychosis Positive and Negative Syndrome Scale (PANSS) score > 60 despite a stable dose of antipsychotic medication. Depressive symptoms were assessed using Montgomery Asberg Depression Scale (MADRS) with a mean score of 73.77 at baseline. Participants received transdermal oestradiol 200 μg or transdermal oestradiol 100 μg or an identical placebo patch. The a priori outcome measure was the change in PANSS score measured at baseline and days 7, 14, 28 and 56, but in this study, we focused on the change in MADRS score at the same time points. Data were analysed by using Quade's rank analysis of covariance (ANCOVA) (Huitema 1980) with baseline MADRS score as a covariate. We found a fluctuating but overall trend towards improvement of comorbid depressive symptoms in women with schizophrenia taking transdermal oestrogen 200 mcg compared with oestrogen 100 mcg or placebo. The stronger 'antidepressant' effect of 200 mcg transdermal oestradiol was found at day 28 (p = 0.03). Our study suggests that adjunctive oestradiol treatment for depression may be a promising treatment for women with comorbid depression and schizophrenia.