Summary:
A great deal of factors can cause sexual dysfunction in schizophrenic patients.
The disease itself, as well as the use of antipsychotic medication.
Antipsychotic medications are associated to different degrees with sexual
dysfunction mainly through their potential to induce hyperprolactinemia.
Prolactin (PRL) secretion is mainly regulated by the hypothalamic dopaminergic
systems. Hyperprolactinemia may cause oligomennorrhea, amenorrhea,
galactorrhea, gynecomastia, oligospermia, osteoporosis and cancer. It also
affects libido, arousal and orgasm.
Current guidelines for the management of treatment-emergent hyperprolactinemia,
primarily recommend dose reduction of antipsychotic medication or switch to a
PRL- sparing agent and alternatively the use of dopamine agonists. The dilemma
becomes more challenging in clinically stable patients who have been well
maintained for a long period on their current antipsychotic medication and for
whom a change in treatment might cause the appearance of side effects and
possibly ultimately the termination of treatment. We therefore conducted this
6-month, parallel-group study to prospectively investigate the effects of the
dopamine agonist cabergoline on sexual dysfunction in clinically stable
patients with schizophrenia (DSM-IV, AP 194) and hyperprolactinemia (PRL>20
ng/ml for men and PRL>25 ng/ml for women), well maintained on a PRL- raising
antipsychotic (risperidone, amisulpride or haloperidole) . The main objective
was to investigate whether cabergoline (CBG) improved sexual functioning in
patients with hyperprolactinemia, without having unfavorable effects on their
psychopathology.
In total 80 patients were enrolled; 33 were receiving risperidone, 17
haloperidol, 11 amisulpride, and 8 risperidone microspheres long acting. Based
on PRL levels (<50, 5099, or >100 ng/ml), patients were assigned in three
cabergoline doses (0.25, 0.5 and 1 mg/day in 38, 23, and 19 patients
respectively). Psychopathology was evaluated using the Positive and Negative
Syndrom Scale (PANSS), and sexual dysfunction with the Arizona Sexual
Experiences Scale (ASEX), the Sexual Functioning Questionnaire and the Sexual
Behaviour Questionnaire. The dosage of the antipsychotic medication remained
stable throughout the study, which lasted for 6 months.
In the whole sample CBG brought a reduction in the PRL levels, which were
reduced in all patients, from 73.3 (±46.8) to 42.0 (±27.8) at month 3 and 27.1
(±20.4) at month 6 (p<0.001). ASEX scores declined from 19.1 (5.1) to 17.6 (
5.5) at month 3 and 15.0 (6.5) at month 6 (p<0.001). The decrease in PRL
levels and in ASEX scores was statistically significant between groups. PANSS
scores were reduced in the 3rd and in the 6th month (p=0.001at 6 month vs.
baseline). There was no unfavorable development in the psychopathology of the
patients. The females had also an improvement in the menstruation cycle.
Our main finding is that cabergoline administration to clinically stable
patients with schizophrenia may improve sexual functioning without adversely
affecting their psychopathologic status, provided that the dose has been suited
to the severity of the hyperprolactinemia. To our knowledge, the present study
provides the first longitudinal data on the clinical management of
antipsychotic medication- induced hyperprolactinemia and sexual function, in
patients with schizophrenia with CBG.
Keywords:
Schizophrenia, Sexual functioning, Antipsychotics, Hyperprolactinemia, Cabergoline
