Seasonal variations in prolactin levels in schizophrenia

Is Adjunct Aripiprazole Effective in Treating Hyperprolactinemia Induced by Psychotropic Medication? A Narrative Review

Psychotropic medication treatment can cause elevated serum prolactin levels and hyperprolactinaemia (HPRL). Reports have suggested that aripiprazole may decrease elevated prolactin. The aim of this review was to assess evidence for the efficacy of adjunct aripiprazole in the treatment of psychotropic-induced HPRL. PubMed and Google Scholar were searched to identify randomised placebo-controlled trials (RCTs) of adjunct aripiprazole in patients with HPRL attributed to primary psychotropic medications. Data for individual patients from case studies, chart reviews and open-label studies were also identified and assessed. Six RCTs, with a total of 609 patients, met inclusion criteria. Primary psychotropics included risperidone, haloperidol, paliperidone, fluphenazine and loxapine. Reductions in prolactin from baseline, before the introduction of aripiprazole, were significantly greater for adjunct aripiprazole than for adjunct placebo in all the studies (p = 0.04 to p < 0.0001). Normalisation of serum prolactin levels was significantly more likely with adjunct aripiprazole than adjunct placebo (p = 0.028 to p < 0.001, data from three studies). Improvement or resolution of HPRL-related symptoms (galactorrhoea, oligomenorrhoea, amenorrhoea and sexual dysfunction) were reported in three studies. Prolactin levels decreased in all case reports and in both of two open-label studies; they normalised in 30/41 patients (73.2%) in case studies and 12/29 (41.4%) in the open-label studies. Adjunct aripiprazole was statistically significantly effective in treating elevated serum prolactin levels in six RCTs. Evidence from case reports and open-label studies suggests a degree of effectiveness in most patients.

The effects of novel and newly approved antipsychotics on serum prolactin levels: a comprehensive review

Since the 1970s, clinicians have increasingly become more familiar with hyperprolactinemia (HPRL) as a common adverse effect of antipsychotic medication, which remains the cornerstone of pharmacological treatment for patients with schizophrenia. Although treatment with second-generation antipsychotics (SGAs) as a group is, compared with use of the first-generation antipsychotics, associated with lower prolactin (PRL) plasma levels, the detailed effects on plasma PRL levels for each of these compounds in reports often remain incomplete or inaccurate. Moreover, at this moment, no review has been published about the effect of the newly approved antipsychotics asenapine, iloperidone and lurasidone on PRL levels. The objective of this review is to describe PRL physiology; PRL measurement; diagnosis, causes, consequences and mechanisms of HPRL; incidence figures of (new-onset) HPRL with SGAs and newly approved antipsychotics in adolescent and adult patients; and revisit lingering questions regarding this hormone. A literature search, using the MEDLINE database (1966-December 2013), was conducted to identify relevant publications to report on the state of the art of HPRL and to summarize the available evidence with respect to the propensity of the SGAs and the newly approved antipsychotics to elevate PRL levels. Our review shows that although HPRL usually is defined as a sustained level of PRL above the laboratory upper limit of normal, limit values show some degree of variability in clinical reports, making the interpretation and comparison of data across studies difficult. Moreover, many reports do not provide much or any data detailing the measurement of PRL. Although the highest rates of HPRL are consistently reported in association with amisulpride, risperidone and paliperidone, while aripiprazole and quetiapine have the most favorable profile with respect to this outcome, all SGAs can induce PRL elevations, especially at the beginning of treatment, and have the potential to cause new-onset HPRL. Considering the PRL-elevating propensity of the newly approved antipsychotics, evidence seems to indicate these agents have a PRL profile comparable to that of clozapine (asenapine and iloperidone), ziprasidone and olanzapine (lurasidone). PRL elevations with antipsychotic medication generally are dose dependant. However, antipsychotics having a high potential for PRL elevation (amisulpride, risperidone and paliperidone) can have a profound impact on PRL levels even at relatively low doses, while PRL levels with antipsychotics having a minimal effect on PRL, in most cases, can remain unchanged (quetiapine) or reduce (aripiprazole) over all dosages. Although tolerance and decreases in PRL values after long-term administration of PRL-elevating antipsychotics can occur, the elevations, in most cases, remain above the upper limit of normal. PRL profiles of antipsychotics in children and adolescents seem to be the same as in adults. The hyperprolactinemic effects of antipsychotic medication are mostly correlated with their affinity for dopamine D2 receptors at the level of the anterior pituitary lactotrophs (and probably other neurotransmitter mechanisms) and their blood-brain barrier penetrating capability. Even though antipsychotics are the most common cause of pharmacologically induced HPRL, recent research has shown that HPRL can be pre-existing in a substantial portion of antipsychotic-naïve patients with first-episode psychosis or at-risk mental state.

Co-occurring SAD symptomatology and schizophrenia at high latitude: a pilot study

OBJECTIVES

Recent research investigates major depression with seasonal pattern, also called seasonal affective disorder (SAD), depression in schizophrenia and seasonality in schizophrenia, but there exits limited research investigating SAD in schizophrenia. This study documents co-occurring SAD symptomatology in patients with schizophrenia at high latitude.

STUDY DESIGN

Clinical cross-sectional study of patients with schizophrenia attending treatment centres in Alaska.

METHOD

Twenty-eight patients completed a structured interview assessing seasonal patterns in mood, depression, negative symptoms of schizophrenia and alcohol use.

RESULTS

Thirty-six percent of patients with schizophrenia met the criteria for SAD used in previous general population research on SAD in Alaska. When a presence of major depressive episode was confirmed using a structured clinical interview for depression in schizophrenia, the rate was 25%. Severity of SAD symptoms was greatest among patients with alcohol-abuse history.

CONCLUSIONS

Co-occurring SAD symptomatology was identified in this extreme latitude sample of patients with schizophrenia. The frequency and severity of symptomatology was greater than found in a general population study of SAD conducted in Alaska using identical criteria. SAD may be under-diagnosed in schizophrenia at moderate and extreme latitudes, highlighting clinical assessment considerations, potential utility of bright light therapy and the need for additional research.

Hormonal responses to the administration of m-chlorophenylpiperazine in patients with seasonal affective disorder and controls

We report on the plasma cortisol and prolactin responses to the serotonergic agonist m-CPP (0.1 mg/kg) in 10 patients with winter seasonal affective disorder (SAD) and 10 controls during the winter, in both untreated and bright light-treated conditions; and on 8 other SAD patients and 8 other controls during the summer. Following m-CPP infusion, untreated patients had exaggerated prolactin (p < .05) and cortisol (p < .05) responses compared to controls. Light treatment significantly reduced responses of both hormones to m-CPP (prolactin: p < .01; cortisol: p < .01). When untreated winter subjects and summer subjects were compared, cortisol, but not prolactin responses to m-CPP were found to be higher in patients than in controls during the winter, and lower in patients than in controls during the summer (diagnosis by season: p < .05). These results are consistent with those of our previous report on the behavioral responses to m-CPP in the same patients and suggest an abnormality in serotonergic function in untreated SAD patients in winter, which is normalized following treatment with light therapy and naturally during the summer.