Medical causes and consequences of hyperprolactinaemia. A context for psychiatrists

Sociodemographic and clinical characteristics related with hyperprolactinaemia in psychiatric clinical population

BACKGROUND

Hyperprolactinaemia (HyperPRL) induced by psychotropic drugs is a high-prevalence consequence which has repercussions in psychical and mental health in the psychiatric population, so this research had the objective to expand which sociodemographic and clinical features are associated with prolactin (PRL) elevation in patients treated with antidepressant and/or antipsychotic drugs.

METHODS

An observational, cross-sectional, comparative and retrolective study was conducted on 300 patients who received clinical attention in a third level of psychiatric care unit in Mexico during 2017. These patients have been reported to show PRL levels greater than 25 ng/mL among women and greater than 20 ng/mL among men. In the same way, sociodemographic and clinical variables were collected, as well as psychiatric diagnosis and type of psychopharmacological treatment used by the patients.

RESULTS

HyperPRL was more frequent in women (80.7%) than men (19.3%). The mean levels of PRL were 68.94 ± 62.28 ng/mL with higher levels in women (71.9 ± 67.3, p=.02). Regarding the treatment, 78.3%, 71.3% and 49.7% consumed antipsychotics, antidepressants, and both drugs, respectively. The relationship between hyperPRL (>100 n/mL) and typical antipsychotics was dose-dependent (33.23 ± 13.24 mg, p=.01). In the multivariate regression models according to the type of treatment, as well as the demographic and clinical features, hyperPRL was associated independently with the use of antipsychotic treatment, pituitary adenoma and hypertension (R²=0.05).

CONCLUSIONS

HyperPRL is a complex clinical syndrome frequent in the psychiatric population with detrimental long-term consequences, as well as its relationship with the use of psychotropic drugs as in the case of antipsychotics. Effective actions should be implemented in the prevention, approach and treatment of this condition paying special attention to the accompanying medical comorbidities.

Prospective analysis of serum prolactin levels, clinical symptomatology and sexual functions in patients with schizophrenia switched to paliperidone palmitate 3-monthly from paliperidone palmitate 1-monthly: Preliminary findings of the first 3 months

OBJECTIVE

Long-acting injectable (LAI) antipsychotics were developed to improve adherence to schizophrenia treatment. Paliperidone palmitate (PP) has two LAI forms: Monthly (PP1M) and three-monthly (PP3M). PP3M shows less difference in Peak-to-Trough drug concentration levels. This could be related to a lower incidence of hyperprolactinemia, which may negatively affect adherence. We aimed to compare prolactin levels and investigate relationships between prolactin levels, symptomatology and sexual function in patients with schizophrenia after switching from PP1M to PP3M.

METHODS

Twenty-five patients were enrolled. The sociodemographic data form, the Positive and Negative Syndromes Scale (PANSS) and the Arizona Sexual Experience Scale (ASEX) were used. Morning blood samples were drawn to determine prolactin levels.

RESULTS

Prolactin level (p < 0.001), the total score and arousal sub-score of ASEX (respectively; p = 0.015, p = 0.020) and the total score and positive scale of PANSS (respectively; p = 0.017, p = 0.021) were decreased on the 90th day (±15 days).

CONCLUSIONS

After switching to PP3M, the decreases in prolactin levels and potentially related sexual side effects was statistically significant. There may be a difference between two formulations of the same drug in terms of side effects, and there is a need for prospective follow-up studies with larger samples.

Proton pump inhibitors therapy and risk of hyperprolactinemia with associated sexual disorders

Proton pump inhibitors (PPIs) are the most widely prescribed medications in the world. According to numerous studies, PPIs have been linked to hyperprolactinemia, which can lead to a variety of sexual and reproductive issues. This review summarizes the effects of numerous PPIs on the blood prolactin levels and associated sexual dysfunctions, which have an effect on the patient's life quality and fertility. The study is taken into account all the available resources till January 31, 2021. Out of total 364, only 27 relevant resources were involved in this review. In certain studies, short-term PPIs use has been shown to have little or no effect on the blood prolactin and other reproductive hormones levels. PPIs have been linked to the development of hyperprolactinemia in several case studies with varying degrees of the blood prolactin levels increase seen in individuals taking PPI alone or in combination with medications, like prokinetics. The relative risk of the sexual consequences development, such as gynecomastia, has been documented using lansoprazole and omeprazole in various cohort studies. On the other hand, other bits of data are insufficient to establish a definite relationship that can turn a possibility into certainty. The majority of the literature data is comprising of double-blind, randomized, crossover studies, case reports, and adverse drug reaction incidents reported to various pharmacovigilance centers. To investigate this link, high-quality studies in patients taking PPIs for a longer time period are needed. We conclude this article with a comprehensive discussion of the hyperprolactinemia clinical implications and the PPIs' function.

Integrating machine learning with electronic health record data to facilitate detection of prolactin level and pharmacovigilance signals in olanzapine-treated patients

BACKGROUND AND AIM

Available evidence suggests elevated serum prolactin (PRL) levels in olanzapine (OLZ)-treated patients with schizophrenia. However, machine learning (ML)-based comprehensive evaluations of the influence of pathophysiological and pharmacological factors on PRL levels in OLZ-treated patients are rare. We aimed to forecast the PRL level in OLZ-treated patients and mine pharmacovigilance information on PRL-related adverse events by integrating ML and electronic health record (EHR) data.

METHODS

Data were extracted from an EHR system to construct an ML dataset in 672×384 matrix format after preprocessing, which was subsequently randomly divided into a derivation cohort for model development and a validation cohort for model validation (8:2). The eXtreme gradient boosting (XGBoost) algorithm was used to build the ML models, the importance of the features and predictive behaviors of which were illustrated by SHapley Additive exPlanations (SHAP)-based analyses. The sequential forward feature selection approach was used to generate the optimal feature subset. The co-administered drugs that might have influenced PRL levels during OLZ treatment as identified by SHAP analyses were then compared with evidence from disproportionality analyses by using OpenVigil FDA.

RESULTS

The 15 features that made the greatest contributions, as ranked by the mean (|SHAP value|), were identified as the optimal feature subset. The features were gender_male, co-administration of risperidone, age, co-administration of aripiprazole, concentration of aripiprazole, concentration of OLZ, progesterone, co-administration of sulpiride, creatine kinase, serum sodium, serum phosphorus, testosterone, platelet distribution width, α-L-fucosidase, and lipoprotein (a). The XGBoost model after feature selection delivered good performance on the validation cohort with a mean absolute error of 0.046, mean squared error of 0.0036, root-mean-squared error of 0.060, and mean relative error of 11%. Risperidone and aripiprazole exhibited the strongest associations with hyperprolactinemia and decreased blood PRL according to the disproportionality analyses, and both were identified as co-administered drugs that influenced PRL levels during OLZ treatment by SHAP analyses.

CONCLUSIONS

Multiple pathophysiological and pharmacological confounders influence PRL levels associated with effective treatment and PRL-related side-effects in OLZ-treated patients. Our study highlights the feasibility of integration of ML and EHR data to facilitate the detection of PRL levels and pharmacovigilance signals in OLZ-treated patients.

Prolactin ordering patterns in psychiatric inpatients and the impact this has on patient management

OBJECTIVE

Guidelines stipulate that baseline prolactin be ordered prior to commencing antipsychotic treatment to facilitate investigation of any subsequent hyperprolactinaemic symptoms. The aim was to observe when and why prolactin levels are ordered for psychiatry inpatients commencing or continuing antipsychotics and how this alters clinical management.

METHODS

Psychiatry inpatients admitted to the Alfred Hospital, Melbourne, Australia, in 2018 with the diagnoses of psychosis, schizophrenia, schizo-affective disorder or bipolar affective disorder were retrospectively analysed. Results and clinical history data were collected in patients in whom prolactin was ordered during or within 12 months of the relevant admission.

RESULTS

Of 592 patients admitted during this period, 90 had prolactin ordered. Eight (8.9%) of the 90 tests were for hyperprolactinaemic symptoms, while the remainder were routine blood work. The results altered clinical management in 10 of the 90 (11.1%) patients. Of these 10, 8 were symptomatic. In the six patients with first episode psychosis, only one had prolactin ordered prior to antipsychotic commencement.

CONCLUSIONS

Adherence to guideline recommendations of baseline prolactin testing was poor. When established on antipsychotics, measuring prolactin rarely changed management in asymptomatic patients; however, it did in those with hyperprolactinaemic symptoms. Measuring prolactin in asymptomatic patients on antipsychotics appears unhelpful.

Prevalence and risk factors of hyperprolactinemia among patients with various psychiatric diagnoses and medications

OBJECTIVES

Hyperprolactinemia is a common adverse event associated with psychotropic medications (mainly antipsychotics) used in the management of schizophrenia and bipolar disorders. The aim of this study was to estimate the prevalence of hyperprolactinemia in psychiatric patients and to evaluate its association with various psychiatric diagnoses and the use of various psychotropic medications.

METHODS

A cross-sectional observational study was conducted between July 2012 and June 2014. Patients were recruited from a number of hospitals located in the five regions of Saudi Arabia. Hyperprolactinemia was defined as blood prolactin levels >25 ng/mL in females and >20 ng/mL in males, regardless of the presence of symptoms.

RESULTS

A total of 997 patients (553 males and 444 females) were included in the current analysis. The average blood prolactin level was 32.6 ± 44.1 ng/mL, with higher levels among females than males (42.9 ± 61.3 versus 24.4 ± 18.6, p < .001). The prevalence of hyperprolactinemia was 44.3%, with no significant gender difference (41.9% in females versus 46.3% in males, p = .164) but with huge variability according to individual antipsychotic and other psychotropic medications. In the multivariate analysis adjusted for demographic and clinical characteristics, hyperprolactinemia was independently and positively associated with using antipsychotic medications (OR = 2.08, 1.26-3.42, p = .004). Additionally, previous hospitalisation, diabetes and hypothyroidism were positively associated, whereas having primary depressive disorders was negatively associated.

CONCLUSIONS

We report a high prevalence of hyperprolactinemia among a large sample of psychiatric patients in Saudi Arabia, which was linked to the use of antipsychotic medications. Routine measurement of blood prolactin levels for all patients maintained on antipsychotic agents is recommended, regardless of symptoms.

Setting standards for physical health monitoring in patients on antipsychotics

Aims and Method

To develop standards for physical health monitoring in patients on antipsychotics in a forensic environment. We reviewed recommendations for physical health checks from key publications and then agreed a consensus on what to monitor and how often.

Results

We developed a standardised form to ensure the requisite minimum monitoring is performed when a patient is newly prescribed an antipsychotic drug or the dose is increased, when an abnormality is detected and for routine annual physical health monitoring.

Clinical Implications

We have produced a pragmatic solution to the gap between the recognised risks to physical health of individuals treated with antipsychotic medication and the need for clear, unambiguous standards of physical healthcare.

Antidopaminergic medication in healthy subjects provokes subjective and objective mental impairments tightly correlated with perturbation of biogenic monoamine metabolism and prolactin secretion

OBJECTIVES

Off-label prescription of antipsychotics to patients without psychotic symptoms has become a routine matter for many psychiatrists and also some general practitioners. Nonetheless, little is known about the possibly detrimental effects of antidopaminergic medications on general psychopathology, subjective mental state, or a possible association with physiological parameters in nonpsychotic individuals.

METHODS

In this randomized, single-blinded study, groups of healthy volunteers (n=18) received low doses of reserpine, aripiprazole, haloperidol, or placebo on 7 successive days. Relevant physiological parameters (plasma prolactin, concentrations of catecholamine metabolites in plasma, and 24-hour urine) and each subject's mental state (Positive and Negative Syndrome Scale, Hamilton Rating Scale for Depression, visual analogue scale, Beck Depression Inventory II) were assessed at the start and end of the trial.

RESULTS

Of the three active treatments, only reserpine caused a significant increase in some plasma- and urine-catecholamine metabolites, but all three medications evoked objective and subjective changes in general psychopathology scores, which correlated with individual increases in plasma homovanillic acid concentrations. Both objective and subjective impairments were significantly more pronounced in the subgroup with greatest increase of plasma prolactin. Subjects experiencing the most pronounced side effects under haloperidol, which compelled them to drop out, showed significantly higher prolactin concentration increases than those who tolerated haloperidol well.

CONCLUSION

We found consistent associations between altered markers of dopamine transmission and several objective and subjective mental impairments in healthy volunteers after 1 week's treatment with antidopaminergic medications. These findings should draw attention to a more intensive risk-benefit evaluation in cases of off-label prescription of antipsychotic medications.

Multidisciplinary consensus on the therapeutic recommendations for iatrogenic hyperprolactinemia secondary to antipsychotics

Hyperprolactinemia is an underappreciated/unknown adverse effects of antipsychotics. The consequences of hyperprolactinemia compromise therapeutic adherence and can be serious. We present the consensus recommendations made by a group of experts regarding the management of antipsychotic-induced hyperprolactinemia. The current consensus was developed in 3 phases: 1, review of the scientific literature; 2, subsequent round table discussion to attempt to reach a consensus among the experts; and 3, review by all of the authors of the final conclusions until reaching a complete consensus. We include recommendations on the appropriate time to act after hyperprolactinemia detection and discuss the evidence on available options: decreasing the dose of the antipsychotic drug, switching antipsychotics, adding aripiprazole, adding dopaminergic agonists, and other type of treatment. The consensus also included recommendations for some specific populations such as patients with a first psychotic episode and the pediatric-youth population, bipolar disorder, personality disorders and the elderly population.

Partial regimen replacement with aripiprazole reduces serum prolactin in patients with a long history of schizophrenia: A case series

AIM

Aripiprazole (ARP) is a popular antipsychotic drug that has demonstrated ameliorative effects on hyperprolactinemia. However, no study to date has studied the utility of ARP in patients with a long history of schizophrenia and antipsychotic treatment. We therefore examined the effect of partial antipsychotic regimen replacement with ARP on hyperprolactinemia induced by chronic antipsychotic use in patients with schizophrenia.

METHODS

Sixteen patients with a schizophrenia diagnosis (F2) based on the International Classification of Diseases (version 10) were recruited. At months 0, 1, 3, and 6 of the study, serum prolactin, body weight, and blood glucose were measured, and QOL and psychotic symptoms were assessed using Global Assessment of Functioning scores and Clinical Global Impressions of Improvement (CGI-I) scores.

RESULTS

Nine patients with an average age of 46.7±9.6 years and mean disease duration of 15.9±10.4 years were included in the final analysis. Serum prolactin levels significantly decreased and GAF and CGI-I scores improved significantly over the 6-month period after partial replacement with ARP. Additionally, no changes were observed in body weight or blood glucose over the 6-month period.

CONCLUSION

Partial antipsychotic regimen replacement with ARP improves hyperprolactinemia, and may improve the QOL of patients with a long history of schizophrenia.

CLINICAL TRIAL REGISTRATION NUMBER

Japan Medical Association, Center for clinical trials D: JMA-IIA00245.

Improving physical health monitoring for patients with chronic mental health problems who receive antipsychotic medications

Physical health monitoring is an integral part of caring for patients with mental health problems. It is proven that serious physical health problems are more common among patients with severe mental health illness (SMI), this monitoring can be challenging and there is a need for improvement.

The project aimed at improving the physical health monitoring among patients with SMI who are receiving antipsychotic medications. The improvement process focused on ensuring there is a good communication with general practitioners (GPs) as well as patient's education and education of care home staff. GP letters requesting physical health monitoring were updated; care home staff and patients were given more information about the value of regular physical health monitoring. There was an improvement in patients' engagement with the monitoring and the monitoring done by GPs was more adherent to local and national guidelines and was communicated with the mental health service.

Is amisulpride safe when prescribed to breast and prostate cancer patients?

In the last decades, the potential association between antidepressants and cancer risk has been increasingly investigated. Fundamental researches, performed on animal models and cell tumoral lines, have highlighted several biological mechanisms possibly supporting this association. Nevertheless, the epidemiological studies investigating the risk of cancer in patients receiving selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs) have provided conflicting and inconclusive results. Therefore, the prescription of several antidepressants in oncologic patients still remains a matter of discussion. The aim of this review is to present and discuss available evidence concerning the association between the risk of breast and prostate cancer and the use of antidepressant medications. Thus, consistencies, differences, and contradictions of available data are reported. A special focus is addressed to amisulpiride, a widely prescribed drug still poorly investigated with regard to the risk of cancer occurrence and recurrence. Overall, there is no definitive evidence of increased risk of breast and prostate cancer among patients exposed to SSRIs and TCAs. The association between amisulpiride and cancer risk has been to date scarcely explored and considered in clinical settings. Nevertheless, the hyperprolactinemia frequently resulting from its adoption has been repeatedly associated, to increased cancer risk and poorer prognosis in cancer patients. Thus, the use of amisulpiride among cancer patients should be carefully considered.

Drug-induced hypo- and hyperprolactinemia: mechanisms, clinical and therapeutic consequences

INTRODUCTION

The altered profiles of prolactin secretion in the anterior hypophysis, generated by pathological, pharmacological or toxicological causes, have special consequences on multiple functions in both genders.

AREAS COVERED

This selective review presents the main mechanisms controlling prolactin secretion, focusing on the interplay of various neurotransmitters or xenobiotics, but also on the role of psychic or posttraumatic stress. A detailed analysis of several pharmacotherapeutic groups with hyperprolactinemic effects emphasize on the relevance of the pharmacokinetic/pharmacodynamic mechanisms and the clinical significance of the long term administration.

EXPERT OPINION

Accurate monitoring and evaluation of the hyperprolactinemia induced by xenobiotics is strongly recommended. The typical antipsychotics and some of the atypical agents (amisulpride, risperidone, paliperidone), as well as some antidepressants, antihypertensives and prokinetics, are the most important groups inducing hyperprolactinemia. The hyperprolactinemic effects are correlated with their affinity for dopamine D2 receptors, their blood-brain barrier penetration and, implicitly, the requested dose for adequate occupancy of cerebral D2 receptors. Consequently, integration of available pharmacokinetic and pharmacodynamic data supports the idea of therapeutic switch to non-hyperprolactinemic agents (especially aripiprazole) or their association, for an optimal management of antipsychotic-induced hyperprolactinemia. Possible alternative strategies for counteracting the xenobiotics-induced hyperprolactinemia are also mentioned.

High prevalence of chronic pituitary and target-organ hormone abnormalities after blast-related mild traumatic brain injury

Studies of traumatic brain injury from all causes have found evidence of chronic hypopituitarism, defined by deficient production of one or more pituitary hormones at least 1 year after injury, in 25–50% of cases. Most studies found the occurrence of posttraumatic hypopituitarism (PTHP) to be unrelated to injury severity. Growth hormone deficiency (GHD) and hypogonadism were reported most frequently. Hypopituitarism, and in particular adult GHD, is associated with symptoms that resemble those of PTSD, including fatigue, anxiety, depression, irritability, insomnia, sexual dysfunction, cognitive deficiencies, and decreased quality of life. However, the prevalence of PTHP after blast-related mild TBI (mTBI), an extremely common injury in modern military operations, has not been characterized. We measured concentrations of 12 pituitary and target-organ hormones in two groups of male US Veterans of combat in Iraq or Afghanistan. One group consisted of participants with blast-related mTBI whose last blast exposure was at least 1 year prior to the study. The other consisted of Veterans with similar military deployment histories but without blast exposure. Eleven of 26, or 42% of participants with blast concussions were found to have abnormal hormone levels in one or more pituitary axes, a prevalence similar to that found in other forms of TBI. Five members of the mTBI group were found with markedly low age-adjusted insulin-like growth factor-I (IGF-I) levels indicative of probable GHD, and three had testosterone and gonadotropin concentrations consistent with hypogonadism. If symptoms characteristic of both PTHP and PTSD can be linked to pituitary dysfunction, they may be amenable to treatment with hormone replacement. Routine screening for chronic hypopituitarism after blast concussion shows promise for appropriately directing diagnostic and therapeutic decisions that otherwise may remain unconsidered and for markedly facilitating recovery and rehabilitation.

New insights in the management of antipsychotics in the treatment of schizophrenia in a patient with prolactinoma: a case report and review of the literature

Prolactinomas are the commonest pituitary adenomas and the major pathological cause of hyperprolactinaemia. Symptomatic prolactinomas are treated mainly by dopamine agonists; surgery and radiotherapy are options for nonresponders. Schizophrenia treatment is based on antipsychotics, which acts mainly at serotonergic and dopaminergic systems. We report a case of a 39-year-old schizophrenic male patient that was diagnosed with a macroprolactinoma 8 years after his first psychotic episode. The association of Schizophrenia and prolactinoma represents a clinical challenge once the treatment of one disease can exacerbate the symptoms of the other.

A review of hyperprolactinaemia and severe mental illness: Are there implications for clinical biochemistry?

Hyperprolactinaemia is a common adverse event reported in association with treatments used in schizophrenia and bipolar disorder. Recent data are suggestive that hyperprolactinaemia may have a range of significant short-and long-term clinical consequences. The objective of this review is to examine the causes, frequency and clinical consequences of hyperprolactinaemia in the severely mentally ill (SMI) with a focus on patients taking antipsychotic medications. A Medline search was carried out to identify relevant publications. Reference lists from previous review articles were also examined to search for additional data. Hyperprolactinaemia may be one of the most common adverse events associated with some antipsychotic medications. Precise rates with individual drugs had however until recently been poorly categorized. The relationship between hyperprolactinaemia and adverse outcomes in the SMI population appears similar to that in the general population. Adverse outcomes (such as sexual dysfunction) can occur acutely and in the longer term (bone fractures and possibly breast cancer), but the precise link between degree and length of hyperprolactinaemia and adverse outcome remains to be established. In conclusion, hyperprolactinaemia is a common treatment-emergent adverse event of some antipsychotic medications and may have clinical consequences. Physicians must balance the benefits and risks of treatment when determining appropriate therapy for individual patients.

Antidepressant-induced hyperprolactinaemia: incidence, mechanisms and management

Prolactin, a polypeptide hormone, is responsible, amongst other things, for milk production during lactation and breast enlargement during pregnancy. Numerous drugs can affect prolactin levels. Most commonly, conventional antipsychotics are associated with hyperprolactinaemia but there have also been reports of antidepressants causing hyperprolactinaemia. This review sets out to establish the incidence of antidepressant-induced hyperprolactinaemia, its possible mechanism and to determine appropriate remedial actions. Nearly all antidepressants are reported to be associated with hyperprolactinaemia. Incidence rates were not clearly established and symptoms were very rare. The mechanism by which antidepressants may cause hyperprolactinaemia is not fully understood, though several theories have been postulated, such as serotonin stimulation of GABAergic neurons and indirect modulation of prolactin release by serotonin. Patients taking antidepressants presenting to their clinician with symptoms potentially related to hyperprolactinaemia, such as galactorrhoea, should have their plasma prolactin level measured and their antidepressant changed if an increased prolactin level is confirmed. Routine monitoring of prolactin levels is otherwise not appropriate.

Hyperprolactinaemia during treatment with paliperidone

OBJECTIVE

The aim of this paper is to highlight the association between antipsychotic medication, in this instance paliperidone, and hyperprolactinaemia, and discuss the impact of this adverse effect on patient management.

METHOD

Four patients with paliperidone-induced hyperprolactinaemia are described with a brief review of the literature.

RESULTS

Four female patients aged between 20 and 50 years developed hyperprolactinaemia 3 weeks to 4 months after commencement of treatment with paliperidone. The levels were significantly raised above the normal upper limit of 500 mIU/L, ranging between 1500 and 3996 mIU/L, and returned to within the normal range after cessation of the medication (82-381 mIU/L). Two of the patients were asymptomatic despite significant elevation of prolactin; two experienced galactorrhoea, a distressing adverse effect. Subsequent management was significantly affected.

CONCLUSIONS

Routine standardized monitoring of prolactin levels may guide treatment choice, avoiding potential disruption to the therapeutic relationship, enhancing compliance with future medication and preventing negative treatment outcomes. Detailed education should accompany the monitoring process and include discussion of the risks of associated adverse effects of antipsychotic medications versus the benefit of significant symptom relief.

Antipsychotic-induced hyperprolactinaemia in patients with schizophrenia: considerations in relation to bone mineral density

Schizophrenia affects about 1% of the world's population. Those with schizophrenia are at elevated risk of a variety of physical health conditions, including diabetes, coronary heart disease, hypertension and osteoporosis. Osteoporosis secondary to antipsychotic-induced hyperprolactinaemia (i.e. raised prolactin levels) has received little attention, when compared with reports on metabolic syndrome for instance. A recent study established that schizophrenia and prolactin-raising antipsychotic medication is directly associated with hip fractures. This is important and concerning as osteoporotic fractures are associated with much morbidity and mortality. This paper reviews the literature on antipsychotic-induced hyperprolactinaemia and its subsequent effects on bone mineral density.

Antipsychotic-induced hyperprolactinaemia, hypogonadism and osteoporosis in the treatment of schizophrenia

Treatment of schizophrenic illness usually involves the long-term administration of antipsychotic drugs. Most antipsychotic agents antagonise the actions of endogenous dopamine (DA) at DA-2 receptors in the brain. The relative affinity for, and binding time to, DA-2 receptors was considered to be one of the key determinants of the antipsychotic potency of classical antipsychotic drugs. Some newer atypical antipsychotics, of which clozapine is the prototype, have a relatively poor affinity for DA-2 receptors; whereas other atypical antipsychotics are potent DA-2 antagonists. The propensity of antipsychotic agents to cause hyperprolactinaemia is related to their potency in antagonising DA-2 receptors on the anterior pituitary. In our studies, bone loss was consistently related to DA-2 antagonist potency of antipsychotic drugs, rather than their classification using conventional 'typical' versus 'atypical' systems. It is established that hyperprolactinaemia causes suppression of the reproductive endocrine axis and consequent bone mineral density (BMD) loss. Results from our group and others have demonstrated that a similar pathophysiological process is occurring in individuals with antipsychotic-induced hyperprolactinaemia. We found high rates of osteoporosis and osteopenia in those taking long-term antipsychotic drugs, and this was related to the dose and duration of treatment. Bone loss was associated with hypogonadism in male and female groups. Young Caucasian women appear to be particularly vulnerable to developing hyperprolactinaemia and the associated hypogonadism and bone loss. The occurrence of menstrual dysfunction should alert clinical suspicions of hyperprolactinaemia and bone de-mineralisation. Lastly, there are no published trials examining the effects of hormone replacement on BMD in those taking long-term antipsychotic drugs, but preliminary findings from our studies suggest that active management of bone loss in those with antipsychotic-associated bone disease may halt or even reverse this process.

Antipsychotics and hyperprolactinaemia: clinical recommendations

A group of international experts in psychiatry, medicine, toxicology and pharmacy assembled to undertake a critical examination of the currently available clinical guidance on hyperprolactinaemia. This paper summarises the group's collective views and provides a summary of the recommendations agreed by the consensus group to assist clinicians in the recognition, clinical assessment, investigation and management of elevated plasma prolactin levels in patients being treated for severe mental illness. It also deals with the special problems of particular populations, gives advice about information that should be provided to patients, and suggests a strategy for routine monitoring of prolactin. The recommendations are based upon the evidence contained in the supplement 'Hyperprolactinaemia in schizophrenia and bipolar disorder: Clinical Implications' (2008). The guidance contained in this article is not intended to replace national guidance (such as that of the National Institute of Clinical Excellence), however, it does provide additional detail that is unlikely to be covered in existing guidelines, and focuses on areas of uncertainty and disagreement. We hope it will add to the debate about this topic.

Clinical questions and uncertainty--prolactin measurement in patients with schizophrenia and bipolar disorder

Many antipsychotic medications have the potential to raise prolactin levels leading to a range of negative consequences. In addition to symptoms such as gynaecomastia, galactorrhoea, menstrual irregularities and sexual dysfunction it is becoming clear that there are a number of important and potentially serious long-term consequences, including a loss of bone mineral density and a possible association with the development of breast cancer. It is clear, therefore, that the tendency to raise prolactin should be an important consideration in the use of antipsychotics but, to a large degree, this area has been neglected in clinical practice and research when compared with other potential adverse effects. We consider some of the practical clinical issues in prolactin measurement and the management of high results. We will identify the areas of uncertainty that remain for clinicians and consider the practical questions that future research should address.