Peripheral oxytocin is associated with reduced symptom severity in schizophrenia

Background Emerging evidence from clinical trials suggests that oral estrogen and intranasal oxytocin might reduce symptom seventy in schizophrenia Whether increases in endogenous hormones are similarly associated with improved symptoms is unknown We investigated the effects of menstrual cycle phase and related fluctuations in peripheral hormone levels on clinical symptoms in women with chronic schizophrenia Method Twenty three women with schizophrenia were administered the Positive and Negative Syndrome Scale (PANSS) a measure of clinical symptom severity at two menstrual cycle phases 1) early follicular (Days 2-4 low estrogen/progesterone) and 2) midluteal (Days 20-22 high estrogen/progesterone) Twenty-seven males with schizophrenia and 58 controls (31 female) completed testing at comparable intervals Men were Included to examine whether the relationships between clinical symptoms and hormone levels in women generalize to men Plasma hormone assays of estrogen oxytocin progesterone and testosterone were obtained Results Female patients showed less severe symptoms during the midluteal versus early follicular phase (p s<0 01) Oxytocin did not fluctuate across phases but in female patients (p s<0 01) higher oxytocin levels were associated with less severe positive symptoms and overall psychopathology In both sexes higher oxytocin levels were associated with more prosocial behaviors (p<0 05) Conclusion Consistent with previous findings in acutely ill patients our results suggest that clinical symptoms vary across the menstrual cycle in patients with chronic schizophrenia Similar to recent findings regarding benefits of intranasal oxytocin these new findings indicate that high levels of endogenous oxytocin might Improve positive symptom severity and general psychopathology in women and social behaviors in both sexes (C) 2010 Elsevier BV All rights reserved