Hyperprolactinemia in response to antipsychotic drugs: characterization across comparative clinical trials.

BACKGROUND: Atypical antipsychotic drugs for the treatment of schizophrenia provide effective treatment of psychotic symptoms with a safety profile superior to conventional antipsychotic medications. Neuroendocrine abnormalities in patients with schizophrenia, such as chronic hyperprolactinemia, may now potentially be minimized by the use of newer prolactin-sparing antipsychotic drugs. A discrimination of prolactin-sparing versus prolactin-elevating antipsychotic drugs may provide the clinician with treatment choices in order to avoid or mitigate hyperprolactinemia-associated morbidity. METHODS: Results from five clinical trials were used to characterize factors that may influence antipsychotic drug effects on levels of serum prolactin. Factors investigated included drug treatment, gender, time course, potential for reduction or reversibility, and age. RESULTS: Factors that influenced the risk of hyperprolactinemia included gender, with females appearing to be more sensitive than males, and drug treatment, with risperidone and conventional antipsychotic agents increasing prolactin more than olanzapine. Patients of all ages demonstrated sensitivity to increased prolactin. Furthermore, patients with hyperprolactinemia sustained the effect over time. Hyperprolactinemia reversed when patients were switched to a prolactin-sparing antipsychotic medication. CONCLUSION: Effects of antipsychotic medications on serum prolactin are multi-factorial. Evidence for sexual, reproductive, and general medical consequences of antipsychotic-induced hyperprolactinemia is developing, and identifying antipsychotic drugs with a favorable prolactin profile would be important in mitigating these consequences. Most notably for women, atypical or novel antipsychotic drugs with a prolactin-sparing profile may offer effective clinical treatment with preservation of physiological hormonal function.

Prevalence of hyperprolactinemia in schizophrenic patients treated with conventional antipsychotic medications or risperidone.

OBJECTIVE: The prevalence of hyperprolactinemia during treatment with conventional antipsychotic drugs or risperidone is under-recognized and requires further investigation. This open-label study was designed to determine the extent of this potential problem in a routine clinical setting. METHODS: Four hundred and two adult inpatients or outpatients with a diagnosis of schizophrenia, schizophreniform disorder, or schizoaffective disorder were studied in a 1-day, point prevalence trial. Neither clinicians nor patients had any prior knowledge of serum prolactin levels or any potential associated adverse events, and patients were required to have been treated with a conventional antipsychotic drug or risperidone for a minimum of 3 months prior to study entry. Patients taking concomitant medications known to elevate prolactin were excluded. Rigorous assessment of serum prolactin was performed to estimate the prevalence rate of hyperprolactinemia, defined as a level above the upper limit of normal (>18.77 ng/ml for males, and >24.20 ng/ml for females). Patients were stratified within antipsychotic treatment by gender and, for females, by menopausal status. RESULTS: Serum prolactin was obtained from 147 females (age range: 21-69 years; mean age=44.51 years) and 255 males (age range: 18-66 years; mean age=40.76 years). The prevalence of hyperprolactinemia among women of reproductive age (n=90) was 65.6% (mean serum prolactin=69.0 ng/ml), and among postmenopausal women (n=51), it was 45.1% (mean serum PRL=49.0 ng/ml). The prevalence of hyperprolactinemia across all males (n=255) was 42.4% (mean serum PRL= 32.4 ng/ml). The prevalence of hyperprolactinemia among females taking risperidone (N=42) was 88% versus 47.6% of those taking conventional antipsychotic drugs (N=105), with 48% of those females of reproductive age on risperidone experiencing abnormal menstrual cycles (secondary amenorrhea, oligomenorrhea, or polymenorrhea). Of all premenopausal females with hyperprolactinemia, 31.6% had estradiol levels

Olanzapine versus divalproex in the treatment of acute mania.

OBJECTIVE: The effects of olanzapine and divalproex for the treatment of mania were compared in a large randomized clinical trial. METHOD: A 3-week, randomized, double-blind trial compared flexibly dosed olanzapine (5-20 mg/day) to divalproex (500-2500 mg/day in divided doses) for the treatment of patients hospitalized for acute bipolar manic or mixed episodes. The Young Mania Rating Scale and the Hamilton Depression Rating Scale were used to quantify manic and depressive symptoms, respectively. Safety was assessed with several measures. RESULTS: The protocol defined baseline-to-endpoint improvement in the mean total score on the Young Mania Rating Scale as the primary outcome variable. The mean Young Mania Rating Scale score decreased by 13.4 for patients treated with olanzapine (N=125) and 10.4 for those treated with divalproex (N=123). A priori categorizations defined response and remission rates: 54.4% of olanzapine-treated patients responded (> or = 50% reduction in Young Mania Rating Scale score), compared to 42.3% of divalproex-treated patients; 47.2% of olanzapine-treated patients had remission of mania symptoms (endpoint Young Mania Rating Scale < or = 12), compared to 34.1% of divalproex-treated patients. The decrease in Hamilton depression scale score was similar in the two treatment groups. Completion rates for the 3-week study were similar in both groups. The most common treatment-emergent adverse events (incidence >10%) occurring more frequently during treatment with olanzapine were dry mouth, increased appetite, and somnolence. For divalproex, nausea was more frequently observed. The average weight gain with olanzapine treatment was 2.5 kg, compared to 0.9 kg with divalproex treatment. CONCLUSIONS: The olanzapine treatment group had significantly greater mean improvement of mania ratings and a significantly greater proportion of patients achieving protocol-defined remission, compared with the divalproex treatment group. Significantly more weight gain and cases of dry mouth, increased appetite, and somnolence were reported with olanzapine, while more cases of nausea were reported with divalproex.

The Comparative Peripheral Anticholinergic-Like Adverse Event Profiles of Olanzapine and Risperidone.

OBJECTIVE: To test the hypothesis that reported in vitro muscarinic receptor affinity differences between olanzapine and risperidone would be reflected in peripheral solicited anticholinergic adverse event frequencies. METHOD: Data from a double-blind, randomized trial of olanzapine versus risperidone in 339 patients (age range, 18-65 years) with DSM-IV schizophrenia spectrum acute psychosis were retrospectively analyzed. Subgroups based on the median of the mean daily drug dose were constructed (olanzapine 17 mg; risperidone 6 mg). Mean daily dose of adjunctive anticholinergic medication was compared using ANOVA, and frequencies of treatment-emergent solicited adverse events defined by the Association de Méthodologie et de Documentation en Psychiatrie (AMDP-5) were analyzed using categorical methods. RESULTS: Mean daily anticholinergic dose was significantly higher overall for the risperidone group (0.68 +/- 1.27 mg) than for the olanzapine group (0.27 +/- 0.76 mg) (p =.002). When only patients who did not receive anticholinergic adjunct therapy were considered, no significant differences in the frequency of specific anticholinergic adverse events occurred in olanzapine-treated patients as compared with risperidone-treated patients (p >/=.245). There was also no significant difference between olanzapine and risperidone in the frequency of any anticholinergic adverse event (p =.458). CONCLUSION: At clinically effective doses, olanzapine and risperidone did not differ significantly in frequency of peripheral anticholinergic events. These results support the view that, for olanzapine and risperidone, in vitro anticholinergic receptor binding (K(i) values) may not predict in vivo peripheral events.