Prolactin, subjective well-being and sexual dysfunction: an open label observational study comparing quetiapine with risperidone.

INTRODUCTION: Sexual dysfunction is a frequent side effect of antipsychotic treatment. Increased prolactin levels are believed to be responsible for this sexual impairment despite contradictory results. AIM: The primary objective of the present study was to examine the relationship between sexual dysfunction, subjective well-being and prolactin levels in patients with schizophrenia treated either with risperidone or quetiapine. The secondary objective was to explore the relationship between testosterone and the severity of positive and negative symptoms of schizophrenia in male patients. METHODS: In a 4-week nonrandomized open label observational study, 102 inpatients with schizophrenia were recruited. Sexual functioning, subjective well-being and endocrinological parameters were assessed as well as psychopathological characteristics. MAIN OUTCOME MEASURES: Two self-rating questionnaires concerned with sexual functioning ("Essener Fragebogen zur Sexualität") and Subjective Well-Being Under Neuroleptic Treatment Scale (SWN) were completed by the patients. Plasma levels of prolactin in male and female patients were measured. Furthermore, in male patients testosterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were determined. Positive and Negative Symptom Scale (PANSS) was applied. RESULTS: After 4 weeks, patients treated with quetiapine reported less severe sexual impairment, as well as lower PANSS negative and general score compared with patients treated with risperidone. Additionally, emotional regulation as measured with the SWN was higher in patients treated with quetiapine. Risperidone was significantly associated with elevated prolactin levels. Prolactin levels were not correlated either with sexual dysfunction or PANSS. However, in the group of patients treated risperidone, sexual impairment was significantly associated with the SWN subscale emotional regulation. CONCLUSIONS: Increased prolactin levels do not seem to be decisive for antipsychotic induced sexual dysfunction. Improvement of severity of illness and regaining the ability to regulate one's own emotion have positive influence on sexual functioning.

Sensorimotor gating and habituation of the startle response in schizophrenic patients randomly treated with amisulpride or olanzapine.

BACKGROUND: Schizophrenic patients exhibit impairments in prepulse inhibition (PPI) and habituation of the acoustic startle response (ASR). Recent studies suggested that PPI deficits and habituation deficits are normalized after antipsychotic treatment. Despite clear evidence of gating and habituation mechanisms in animal models, it is still unknown which neurotransmitter systems are involved in schizophrenic patients. Thus, we compared the effects of a combined 5-HT2A/D2 and a pure D2/D3 antagonist on PPI and habituation of ASR in patients with schizophrenia. METHODS: The ASR was measured in 37 acute schizophrenic patients who were randomized and double-blinded as to treatment with amisulpride or olanzapine. Patients were assessed during the first week and after four and eight weeks of treatment. Twenty healthy matched control subjects were examined likewise. RESULTS: Schizophrenic patients showed a significant PPI deficit and significantly decreased startle amplitude at baseline. The gating deficit disappeared after antipsychotic treatment in both treatment groups. Amisulpride sensitized the startle amplitude, whereas startle amplitude was not changed by olanzapine. After correcting for startle amplitude, patients did not show a habituation deficit; however, amisulpride accelerated habituation, whereas olanzapine had no effect. CONCLUSIONS: Our findings suggest that the PPI-restoring effect of antipsychotics is probably attributed to a dopamine D2 receptor blockade.

Plasma testosterone and sexual function in men receiving buprenorphine maintenance for opioid dependence.

High-dose methadone is well known to cause testosterone deficiency and sexual dysfunction in opioid-dependent men. Buprenorphine is a new drug for the pharmacotherapy of opioid dependence. Its influence on the gonadal axis has not been investigated to date. We therefore assayed testosterone, free testosterone, estradiol, SHBG, LH, FSH, and prolactin in 17 men treated with buprenorphine. Thirty-seven men treated with high-dose methadone and 51 healthy blood donors served as controls. Sexual function and depression were assessed using a self-rating sexual function questionnaire and the Beck Depression Inventory. Patients treated with buprenorphine had a significantly higher testosterone level [5.1 +/- 1.2 ng/ml (17.7 +/- 4.2 nmol/liter) vs. 2.8 +/- 1.2 ng/ml (9.7 +/- 4.2 nmol/liter); P < 0.0001] and a significantly lower frequency of sexual dysfunction (P < 0.0001) compared with patients treated with methadone. The testosterone level of buprenorphine-treated patients did not differ from that of healthy controls. In conclusion, we demonstrated for the first time that buprenorphine, in contrast with high-dose methadone, seems not to suppress plasma testosterone in heroin-addicted men. To this effect, buprenorphine was less frequently related to sexual side effects. Buprenorphine might therefore be favored in the treatment of opioid dependence to prevent patients from the clinical consequences of methadone-induced hypogonadism.