High plasma oxytocin levels in men with hypersexual disorder

Context Hypersexual disorder (HD) involves excessive, persistent sexual behaviors related to various mood states and the diagnosis compulsive sexual behavior disorder is included as an impulse control disorder in the 11th revision of the International Classification of Diseases. Although the neurobiology behind the disorder is not clear, some studies suggest dysregulated hypothalamic-pituitary-adrenal axis. Oxytocin acts as counterregulatory neuroendocrine hormone to cortisol and is also involved in sexual behavior. Objective We hypothesized that oxytocin may play a role in the pathophysiology of HD with compensatory actions to cortisol. Design Longitudinal. Setting ANOVA clinic (Karolinska University Hospital). Patients or other participants 64 males with HD and 38 age-matched healthy volunteers. Main Outcome Measures Plasma oxytocin levels, measured with radioimmunoassay; Hypersexual Disorder Screening Inventory; and Hypersexual Disorder: Current Assessment Scale for assessing hypersexual symptoms. Interventions A patient subgroup (n = 30) completed the manual-based group-administered cognitive-behavioral therapy (CBT) program for HD, and posttreatment oxytocin levels were measured. Results Hypersexual men (n = 64) exhibited significantly higher oxytocin plasma levels (mean +/- SD: 31.0 +/- 9.9 pM) compared with healthy volunteers (16.9 +/- 3.9 pM; P < 0.001). There were significant positive correlations between oxytocin levels and the rating scales measuring hypersexual behavior. Patients who completed CBT treatment (n = 30) had a significant reduction of oxytocin plasma levels from pretreatment (30.5 +/- 10.1 pM) to posttreatment (20.2 +/- 8.0 pM; P < 0.001). Conclusions The results suggest that the hyperactive oxytocinergic system in hypersexual men may be a compensatory mechanism to attenuate hyperactive stress.