Adjunctive metformin for antipsychotic-induced hyperprolactinemia: A systematic review

The research trend of hyperprolactinemia from 2011 to 2023 was analyzed by bibliometrics

The objective of this study is to conduct a bibliometric analysis of research trends in hyperprolactinemia from 2011 to 2023. This analysis aims to provide researchers with insights into the current hotspots and frontiers related to hyperprolactinemia. It is worth noting that there are currently no existing reports on bibliometric analyses of hyperprolactinemia. The Social Science Citation Index (SSCI) and Science Citation Index Expanded (SCIE) databases of the Web of Science Core Collection were systematically searched for "articles" and "review articles" related to the topic of hyperprolactinemia from 2011 to 2023. VOSviewer was employed to conduct bibliometric analysis, aiming to analyze the research trends in hyperprolactinemia over the past 13 years. A total of 1865 eligible articles were retrieved, with contributions from 9544 scholars representing 83 countries in the field of research. The United States had the highest number of publications, followed by China. The keywords were categorized into six clusters: (1) etiology of hyperprolactinemia and other related endocrine and metabolic diseases. (2) Hyperprolactinemia and mental illness. (3) Diagnosis and management of hyperprolactinemia. (4) Treatment of hyperprolactinemia and prolactinoma. (5) Detection of macroprolactin and macroprolactinemia. (6) Symptoms of male hyperprolactinemia. Over the past 13 years, there has been a consistent and slightly increasing trend in the number of research papers focusing on hyperprolactinemia. The primary areas of research focus are centered around the diagnosis and treatment of hyperprolactinemia caused by antipsychotic drugs or prolactinoma.

Autoimmune Thyroiditis Mitigates the Effect of Metformin on Plasma Prolactin Concentration in Men with Drug-Induced Hyperprolactinemia

Metformin inhibits the secretory function of overactive anterior pituitary cells, including lactotropes. In women of childbearing age, this effect was absent if they had coexisting autoimmune (Hashimoto) thyroiditis. The current study was aimed at investigating whether autoimmune thyroiditis modulates the impact of metformin on the plasma prolactin concentration in men. This prospective cohort study included two groups of middle-aged or elderly men with drug-induced hyperprolactinemia, namely subjects with concomitant Hashimoto thyroiditis (group A) and subjects with normal thyroid function (group B), who were matched for baseline prolactin concentration and insulin sensitivity. Titers of thyroid peroxidase and thyroglobulin antibodies, levels of C-reactive protein, markers of glucose homeostasis, concentrations of pituitary hormones (prolactin, thyrotropin, gonadotropins, and adrenocorticotropic hormone), free thyroxine, free triiodothyronine, testosterone, and insulin growth factor-1 were measured before and six months after treatment with metformin. Both study groups differed in titers of both antibodies and concentrations of C-reactive protein. The drug reduced the total and monomeric prolactin concentration only in group B, and the impact on prolactin correlated with the improvement in insulin sensitivity and systemic inflammation. There were no differences between the follow-up and baseline levels of the remaining hormones. The results allow us to conclude that autoimmune thyroiditis mitigates the impact of metformin on prolactin secretion in men.

Treatment of antipsychotic-induced hyperprolactinemia: an umbrella review of systematic reviews and meta-analyses

Background

Hyperprolactinemia is a common antipsychotic-induced adverse event in psychiatric patients, and the quality of clinical studies investigating the best treatments has varied. Thus, to better summarize the clinical evidence, we performed an umbrella review of overlapping systematic reviews and meta-analyses for the treatment of antipsychotic-induced hyperprolactinemia.

Methods

The PubMed, Cochrane Library, PsycINFO, Scopus and EMBASE were searched, and reviews and meta-analyses meeting our inclusion criteria were selected. Relevant data were extracted, and an umbrella review was conducted of all included meta-analyses. The quality of included meta-analyses was assessed by using PRISMA scores and AMSTAR 2 quality evaluation. Finally, the clinical evidence for appropriate treatments was summarized and discussed.

Results

Five meta-analyses published between 2013 and 2020 met the requirements for inclusion in this umbrella review. The PRISMA scores of the included meta-analyses ranged from 19.5-26. AMSTAR 2 quality evaluation showed that 2 of the 5 included meta-analyses were of low quality and 3 were of very low quality. The included meta-analyses provide clinical evidence that adding aripiprazole or a dopamine agonist can effectively and safely improve antipsychotic-induced hyperprolactinemia. Two meta-analyses also showed that adjunctive metformin can reduce serum prolactin level, but more clinical trials are needed to confirm this finding.

Conclusion

Adjunctive dopamine agonists have been proven to be effective and safe for the treatment of antipsychotic-induced hyperprolactinemia. Among the researched treatments, adding aripiprazole may be the most appropriate.

Aprepitant boasted a protective effect against olanzapine-induced metabolic syndrome and its subsequent hepatic, renal, and ovarian dysfunction; Role of IGF1/p-AKT/FOXO1 and NFκB/IL-1β/TNF-α signaling pathways in female Wistar albino rats

Olanzapine-induced metabolic syndrome (MS) is a primary risk factor for insulin resistance, hepatorenal damage, and polycystic ovarian syndrome. The objective of the current study was to assess the protective effects of aprepitant (AP) against MS caused by olanzapine and the associated ovarian, renal, and liver dysfunction via modulation of IGF1/p-AKT/FOXO1 and NFκB/IL-1β/TNF-α signaling pathways. AP mitigated all biochemical and histopathological abnormalities induced by olanzapine and resulted in a significant reduction of serum HOMA-IR, lipid profile parameters, and a substantial decrease in hepatic, renal, and ovarian MDA, IL-6, IL-1β, TNF-α, NFκB, and caspase 3. Serum AST, ALT, urea, creatinine, FSH, LH, and testosterone also decreased significantly by AP administration. The FOXO 1 signaling pathway was downregulated in the AP-treated group, while GSH, SOD, and HDL cholesterol levels were elevated.

Impaired Prolactin-Lowering Effects of Metformin in Women with Polycystic Ovary Syndrome

The effect of metformin on prolactin concentration seems to be sex-dependent. The aim of this study was to determine whether the androgen status modulates the impact of metformin on plasma prolactin levels in women. This study included two matched groups of prediabetic women with hyperprolactinemia: 25 with PCOS and 25 control subjects with androgen levels within the reference range and with normal ovarian morphology. Glucose homeostasis markers, prolactin, the remaining anterior pituitary hormones, sex hormones, SHBG and IGF-1 were determined before and after six months of metformin treatment. At baseline, both groups differed in LH, LH/FSH ratio, testosterone, FAI, DHEA-S, androstenedione and estradiol. Although metformin improved insulin sensitivity and increased SHBG in both study groups, these effects were more pronounced in control subjects than in women with PCOS. In control subjects, the drug decreased total and monomeric prolactin and increased LH. In women with PCOS, metformin reduced LH, LH/FSH ratio, testosterone and FAI. In the control group, the impact on total and monomeric prolactin positively correlated with their baseline levels and with the degree of improvement in insulin sensitivity, as well as negatively correlated with testosterone and FAI. In women with PCOS, treatment-induced changes in testosterone and FAI positively correlated with the changes in LH and LH/FSH ratio. The obtained results suggest that the prolactin-lowering properties of metformin are less pronounced in women with coexisting PCOS than in women with elevated prolactin levels, probably owing to the increased production of endogenous testosterone.

Impaired Gonadotropin-Lowering Effects of Metformin in Postmenopausal Women with Autoimmune Thyroiditis: A Pilot Study

Metformin has been found to reduce elevated gonadotropin levels. Hashimoto's thyroiditis is the most common thyroid disorder in iodine-sufficient areas, and it often develops in postmenopausal women. The aim of this study was to investigate whether autoimmune thyroiditis determines the impact of metformin on gonadotrope secretory function. Two matched groups of postmenopausal women were studied: 35 with euthyroid Hashimoto's thyroiditis (group A) and 35 without thyroid disorders (group B). Throughout the study, all participants received oral metformin (2.55-3 g daily). Plasma glucose, insulin, gonadotropins, estradiol, progesterone, thyrotropin, free thyroid hormones, prolactin, adrenocorticotropic hormone, insulin-like growth factor-1, hsCRP, thyroid peroxidase, and thyroglobulin antibody titers were measured at the beginning of the study and six months later. At entry, both groups differed in thyroid peroxidase antibody titers, thyroglobulin antibody titers, and hsCRP levels. In group A, baseline antibody titers correlated positively with hsCRP and negatively with insulin sensitivity. Although metformin improved glucose homeostasis and reduced hsCRP levels in both study groups, these effects were more pronounced in group B than in group A. Only in group B did metformin decrease FSH levels and tend to reduce LH levels. Thyroid antibody titers and the levels of the remaining hormones did not change throughout the study. The impact of metformin on gonadotropin levels correlated with their baseline values and the degree of improvement in insulin sensitivity, as well as with the baseline and treatment-induced reduction in hsCRP. Moreover, the impact on gonadotropins and insulin sensitivity in group A depended on baseline antibody titers. The obtained results indicate that coexisting autoimmune thyroiditis impairs the gonadotropin-lowering effects of metformin in postmenopausal women.

The Effect of Metformin on Plasma Prolactin Levels in Young Women with Autoimmune Thyroiditis

Metformin decreases elevated prolactin levels, which are frequently found in patients with thyroid disorders. The aim of this study was to investigate whether thyroid autoimmunity modulates the impact of metformin on lactotrope secretory function. This study compared two matched groups of young women with prediabetes and mild-to-moderate prolactin excess: 28 subjects with coexisting euthyroid autoimmune thyroiditis (group 1) and 28 individuals without thyroid disorders (group 2), treated for six months with metformin (3 g daily). Thyroid antibody titers, glucose homeostasis markers, prolactin, thyrotropin, free thyroid hormones, FSH, LH, ACTH, IGF-1 and hsCRP were assessed at the beginning and at the end of the study. At entry, the study groups differed in antibody titers and hsCRP levels. Although the improvement in glucose homeostasis and the decrease in hsCRP levels were observed in both study groups, they were more pronounced in group 2. Only in group 2 did metformin reduce circulating prolactin levels (both total and monomeric). Prolactin-lowering properties of metformin positively correlated with baseline prolactin levels, baseline antibody titers (in group 1) and with the degree of reduction in hsCRP levels. The obtained results suggest that autoimmune thyroiditis may attenuate the impact of metformin on lactotrope secretory function.

Co-prescription of aripiprazole on prolactin levels in long-term hospitalized chronic schizophrenic patients with co-morbid type 2 diabetes: A retrospective clinical study

BACKGROUND

One of the most frequent side effects of atypical antipsychotics is hyperprolactinemia (HPRL), and metformin or aripiprazole co-prescription is regarded as an effective therapy option for reducing prolactin (PRL) levels. However, whether either of the two drugs can reduce PRL levels in patients with long-term hospitalized chronic schizophrenia with co-morbid type 2 diabetes (T2DM) has not been adequately reported.

METHODS

In our study, long-term hospitalized chronic schizophrenia patients with co-T2DM who were prescribed olanzapine or risperidone as the primary antipsychotic medication were enrolled. A total of 197 of these cases with co-prescribed aripiprazole were set up as the study group (co-Ari group), and the other 204 cases without co-prescribed aripiprazole were set up as the control group (non-Ari group). The two groups' variations in each target parameter were compared, and the variables affecting PRL levels were examined.

RESULTS

Compared to the non-Ari group, fasting blood glucose (FBG), blood uric acid (UA), total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) levels were significantly higher in the co-Ari group, but there was no difference in PRL levels. Co-prescribing aripiprazole had no impact on PRL levels in all patients with co-T2DM, and aripiprazole dose had no impact on PRL levels in the clinical subgroup of the co-Ari group.

CONCLUSION

Aripiprazole not only worsened the severity of index disturbances associated to metabolism in long-term hospitalized chronic schizophrenia patients with co-T2DM on metformin-based hypoglycemic medications but also failed to lower PRL levels.

Metformin attenuates the production and proliferative effects of prolactin induced by medroxyprogesterone acetate during fertility-sparing treatment for endometrial cancer

Background

Progestin is used for fertility-sparing treatment in cases of endometrial cancer (EC). Progestin can induce hyperprolactinemia by increasing pituitary secretion and endometrial decidualization. However, progestin induces prolactin (PRL) secretion, which stimulates cell proliferation and deleteriously affects treatment. To date, the detrimental effect of PRL, the secretion of which is induced by medroxyprogesterone acetate (MPA) during fertility-sparing treatment, has not yet been fully elucidated. Therefore, we aimed to assess the effects of PRL on EC cells during combined treatment with progestin and metformin.

Methods

In total, 71 patients with EC/endometrial atypical hyperplasia who underwent fertility-sparing treatment at our institution from 2009–2019 were enrolled. Serum PRL levels were determined using enzyme immunoassays; mRNA levels in endometrial tissues were determined using quantitative reverse-transcription PCR. To evaluate MPA-induced decidualization, cancer-associated stromal cells were enzymatically released from surgically removed specimens of six patients with EC. To examine PRL-induced cell proliferation, the EC cell lines Ishikawa, HEC1B, and HEC265 were used. In vitro cell proliferation was evaluated using the WST assay; protein levels of signaling molecules were determined using western blotting.

Results

MPA administration significantly increased serum PRL levels at 3 and 6 months and upregulated IGFBP-1 and PRL mRNA expression in tissues at 3 months of fertility-sparing treatment. Metformin significantly reduced MPA-induced IGFBP-1 and PRL mRNA expression during fertility-sparing treatment and significantly inhibited the upregulation of IGFBP-1 and PRL mRNA and PRL levels due to decidualization induced by MPA and cAMP treatment in primary cultured EC stromal cells. In vitro, PRL increased cell proliferation and ERK1/2 phosphorylation levels, whereas metformin attenuated these increases.

Conclusions

MPA upregulated PRL levels in serum and endometrial tissues during fertility-sparing treatment. Metformin co-administration reduced PRL production and attenuated PRL-induced cell-proliferation activity. This study may provide valuable insights on the application of metformin to improve the outcomes of fertility-sparing treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09858-w.

Pharmacological treatment strategies for antipsychotic-induced hyperprolactinemia: a systematic review and network meta-analysis

Antipsychotic-induced hyperprolactinemia (AP-induced HPRL) occurs overall in up to 70% of patients with schizophrenia, which is associated with hypogonadism and sexual dysfunction. We summarized the latest evidence for the benefits of prolactin-lowering drugs. We performed network meta-analyses to summarize the evidence and applied Grading of Recommendations Assessment, Development, and Evaluation frameworks (GRADE) to rate the certainty of evidence, categorize interventions, and present the findings. The search identified 3,022 citations, 31 studies of which with 1999 participants were included in network meta-analysis. All options were not significantly better than placebo among patients with prolactin (PRL) less than 50 ng/ml. However, adjunctive aripiprazole (ARI) (5 mg: MD = -64.26, 95% CI = -87.00 to -41.37; 10 mg: MD = -59.81, 95% CI = -90.10 to -29.76; more than 10 mg: MD = -68.01, 95% CI = -97.12 to -39.72), switching to ARI in titration (MD = -74.80, 95% CI = -134.22 to -15.99) and adjunctive vitamin B6 (MD = -91.84, 95% CI = -165.31 to -17.74) were associated with significant decrease in AP-induced PRL among patients with PRL more than 50 ng/ml with moderated (adjunctive vitamin B6) to high (adjunctive ARI) certainty of evidence. Pharmacological treatment strategies for AP-induced HPRL depends on initial PRL level. No effective strategy was found for patients with AP-induced HPRL less than 50 ng/ml, while adjunctive ARI, switching to ARI in titration and adjunctive high-dose vitamin B6 showed better PRL decrease effect on AP-induced HPRL more than 50 ng/ml.

Metformin in the Treatment of Amisulpride-Induced Hyperprolactinemia: A Clinical Trial

Objective

To evaluate the efficacy and safety of metformin in the treatment of amisulpride-induced hyperprolactinemia.

Methods

A total of 86 schizophrenic patients who developed hyperprolactinemia after taking amisulpride were screened and randomly assigned to the metformin group (42 patients) and placebo group (44 patients) and followed up for eight weeks. The patients’ serum prolactin levels, blood glucose and lipids were measured at the baseline and the end of the intervention. The treatment emergent symptom scale (TESS) was also assessed.

Results

After eight weeks of intervention, serum prolactin levels in the metformin group decreased from (1737.360 ± 626.918) mIU/L at baseline to (1618.625 ± 640.865) mIU/L, whereas serum prolactin levels in the placebo group increased from (2676.470 ± 1269.234) mIU/L at baseline to (2860.933 ± 1317.376) mIU/L. There was a significant difference in prolactin changes (F^covariance = 9.982, P = 0.002) between the two groups. There was no significant difference in the incidence of adverse drug reactions (P > 0.05) between the two groups.

Conclusion

Metformin is able to improve amisulpride-induced hyperprolactinemia with its safety.

Risperidone Induced Hyperprolactinemia: From Basic to Clinical Studies

Risperidone is one of the most commonly used antipsychotics (AP), due to its safety and efficacy in reducing psychotic symptoms. Despite the favorable side effect profile, the therapy is accompanied by side effects due to the non-selectivity of this medicine. This review will briefly highlight the most important basic and clinical findings in this area, consider the clinical effects of AP-induced hyperprolactinemia (HPL), and suggest different approaches to the treatment.The route of application of this drug primarily affects the daily variation and the total concentration of drug levels in the blood, which consequently affects the appearance of side effects, either worsening or even reducing them. Our attention has been drawn to HPL, a frequent but neglected adverse effect observed in cases treated with Risperidone and its secondary manifestations. An increase in prolactin levels above the reference values result in impairment of other somatic functions (lactation, irregular menses, fertility) as well as a significant reduction in quality of life. It has been frequently shown that the side effects of the Risperidone are the most common cause of non-compliance with therapy, resulting in worsening of psychiatric symptoms and hospitalization. However, the mechanism of Risperidone-induced HPL is complicated and still far from fully understood. Most of the preclinical and clinical studies described in this study show that hyperprolactinemia is one of the most common if not the leading side effect of Risperidone therefore to improve the quality of life of these patients, clinicians must recognize and treat HPL associated with the use of these drugs.

Factors influencing prolactin levels in chronic long-term hospitalized schizophrenic patients with co-morbid type 2 diabetes mellitus

BACKGROUND

For long-term hospitalized patients suffering from schizophrenia, metabolic disease and hyperprolactinemia (HPRL) are common comorbidities. This article is aimed at analyzing the factors influencing comorbid type 2 diabetes mellitus (T2DM) on prolactin (PRL) levels in long-term hospitalized patients suffering from schizophrenia.

METHODS

This study included 378 long-term hospitalized patients with schizophrenia. Common metabolic markers and PRL levels of included samples were collected, and the severity of psychopathology was assessed using the Positive and Negative Symptoms Scale (PANSS). Based on the patients with or without T2DM, the samples were divided into two groups. The differences in clinical parameters between the two groups were compared, and the effects of the parameters on the PRL levels were analyzed.

RESULTS

Compared with non-DM patients, the patients in the DM subgroup had lower PRL levels (P < 0.0001) and rather severe psychiatric symptoms (P = 0.016). Female, treated by risperidone, and high levels of triglyceride (TG) were faced with risk for HPRL (B = 26.31, t = 5.39, P < 0.0001; B = 19.52, t = 4.00, P < 0.0001; B = 2.71, t = 2.31, P = 0.022, respectively). Meanwhile, co-morbid DM and aripiprazole treatment were protective factors (B = 15.47, t = 3.05, P = 0.002; B = -23.77, t = -2.47, P = 0.014; respectively). Ultimately, in the DM subgroup, the dose of metformin was found to be a protective factor for HPRL (B = -0.01, t = -1.46, P = 0.047), while female and aripiprazole were risk factors (B = 16.06, t = 3.26, P = 0.001; B = 20.13, t = 2.57, P = 0.011; respectively).

CONCLUSION

Aripiprazole is a protective factor for HPRL in long-term hospitalized patients, whereas the female is a risk factor. Metformin is beneficial in reducing PRL levels in patients with co-morbid DM. More aggressive and effective interventions are required for preventing adverse drug reactions in women and patients with co-DM.

Hypothalamic-pituitary-gonadal axis and sexual functioning in metformin-treated men after discontinuation of testosterone replacement therapy: A pilot study

WHAT IS KNOWN AND OBJECTIVE

Metformin was found to reduce elevated gonadotropin levels. The aim of the present study was to determine whether metformin modulates the impact of discontinuation of testosterone therapy on hypothalamic-pituitary-gonadal axis activity and sexual function in men with low testosterone levels.

METHODS

The study included 28 men with late-onset hypogonadism (defined according to the criteria of the European Male Aging Study group) receiving testosterone undecanoate (120 mg in three equal doses), 12 of whom had been treated with oral metformin (1.7-3 g daily). Both testosterone and metformin had been administered for at least six months before enrolment. In all patients, testosterone replacement required to be discontinued. The control group included 16 testosterone- and metformin-treated men with late-onset hypogonadism who during the entire study period continued their treatment. Glucose homeostasis markers, as well as plasma levels of insulin, gonadotropins, testosterone, calculated bioavailable testosterone, dehydroepiandrosterone-sulphate, oestradiol, thyrotropin, free thyroxine, prolactin, insulin-growth factor-1 and cortisol were measured at the beginning of the study and four months later. Moreover, at the beginning and the end of the study, all enrolled patients completed a questionnaire assessing their sexual functioning (IIEF-15).

RESULTS AND DISCUSSION

Discontinuation of testosterone therapy resulted in a decrease in total testosterone and bioavailable testosterone (by 42% and 45% in metformin-treated patients, and by 52% and 54% in metformin-naïve patients), as well as impaired all aspects of male sexual function. Changes in bioavailable testosterone, as well as in erectile function, orgasmic function and sexual desire were less pronounced if subjects received metformin. Only in metformin-naïve men, follow-up FSH and LH levels were higher than at baseline (by 75% and 62%). Moreover, discontinuation of testosterone therapy in metformin-naïve men increased glycated haemoglobin, as well as worsened insulin sensitivity. There were no differences between baseline and follow-up levels of the remaining hormones. In metformin-naïve subjects, the increase in gonadotropin levels correlated with the changes in testosterone levels and insulin sensitivity. No effect on glucose homeostasis markers, hormone levels and sexual functioning was observed in the control group.

WHAT IS NEW AND CONCLUSION

The obtained results suggest that metformin treatment mitigates the unfavourable effect of discontinuation of testosterone treatment on hypothalamic-pituitary-testicular axis activity and sexual function in men with late-onset hypogonadism.

The impact of metformin on prolactin levels in postmenopausal women

WHAT IS KNOWN AND OBJECTIVE

Metformin-induced reduction in prolactin levels is more pronounced in users of hormonal contraception than in non-users. The current study was aimed at investigating whether physiological concentrations of estradiol determine the impact of metformin on lactotrope secretory function.

METHODS

We studied two matched groups of postmenopausal women with elevated prolactin levels. Twenty-three women were on hormone replacement therapy (group 1), while the remaining ones (group 2, n = 23) did not use sex hormones. Because of coexistent prediabetes, all individuals received metformin (2.55-3 g daily) for the following six months. Circulating levels of total prolactin, monomeric prolactin, thyrotropin, gonadotropins, free thyroid hormones and estradiol were determined at the beginning and at the end of the study.

RESULTS AND DISCUSSION

Compared with group 1, group 2 was characterized by higher gonadotropin levels and lower estrogen levels. Although metformin reduced monomeric prolactin levels in both study groups, this effect was more pronounced in group 1 than in group 2. Only in group 1, metformin decreased total prolactin levels, while only in group 2 the drug reduced FSH levels. Metformin treatment did not affect circulating levels of the remaining hormones. The impact of metformin on total and monomeric prolactin levels correlated with baseline prolactin levels and with the degree of improvement in insulin sensitivity.

WHAT IS NEW AND CONCLUSION

The obtained results indicate that the impact of metformin on lactotrope secretory function is partially determined by the estrogen status of patients.

Guidance on the treatment of antipsychotic-induced hyperprolactinemia when switching the antipsychotic is not an option

Disclaimer

In an effort to expedite the publication of articles related to the COVID-19 pandemic, AJHP is posting these manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

Purpose

This article aims to evaluate management options for antipsychotic-induced hyperprolactinemia and associated treatment considerations such as efficacy, tolerability, drug interactions, contraindications, and dosing regimens.

Summary

Hyperprolactinemia is a common adverse effect of antipsychotics. First-line management includes reducing the dose of the offending antipsychotic, discontinuing the antipsychotic, or switching to another antipsychotic associated with a lower risk of hyperprolactinemia. However, these options are not always practical and are associated with a risk of relapse of the psychiatric illness. Other management options include adjunctive aripiprazole, dopamine agonists (cabergoline and bromocriptine), metformin, and herbal supplements. A search of Embase, PubMed, and Google Scholar using key terms such as hyperprolactinemia, prolactin, antipsychotic, treatment guidelines, aripiprazole, dopamine agonist, cabergoline, bromocriptine, metformin, herbals, supplements, and medications was conducted for literature retrieval. Upon evaluation of the available literature we found the following: (1) aripiprazole is safe and effective in lowering prolactin levels within normal limits; (2) adjunctive cabergoline and bromocriptine decrease elevated prolactin levels, while cabergoline may be more effective in reducing prolactin but can also be associated with a more serious adverse effect of cardiac valvular abnormalities; (3) metformin causes a mild reduction of prolactin levels; and (4) there are limited data to support use of herbal medications (chamomile, Peony-Glycyrrhiza decoction, and shakuyaku-kanzo-to) in antipsychotic-induced hyperprolactinemia

Conclusion

There are treatments available for antipsychotic-induced hyperprolactinemia in patients who are unable to alter their current antipsychotic regimen. However, there remains a need for additional short- and long-term studies to determine the efficacy and safety of these treatment strategies, given that patients taking antipsychotics typically require chronic, life-long treatment for their illnesses.

How and when to treat the most common adverse effects of antipsychotics: Expert review from research to clinical practice

OBJECTIVE

As most treatment guidelines for antipsychotics focus on clinical efficacy, we will instead focus on adverse effects and how to manage them. In this review, we aim to provide an up-to-date clinical resource for providers who prescribe antipsychotics and have included here "what's new" and "what to do" for numerous antipsychotic-induced adverse effects.

METHODS

A review was performed of relevant literature, studies, randomized clinical trials, and systematic reviews. This information was combined with the clinical experience of the authors to formulate a practical guide for treating adverse effects of antipsychotics with an emphasis on metabolic and movement disorder adverse effects and brief mention of some others (sedation and sexual dysfunction).

CONCLUSIONS

Antipsychotics are an integral part of psychiatric care and are often prescribed lifelong. When choosing an antipsychotic, special consideration must be given to adverse effects which have an undeniable impact on quality of life and can often be the deciding factor in patients' medication compliance. While patients may respond well to one specific medication, they may still experience adverse effects that lead them to discontinue it or switch to a more tolerable but less effective option. However, strategies do exist for managing and treating adverse effects, especially metabolic and movement adverse effects, allowing better personalization of antipsychotic choice.

Antipsychotic-induced Hyperprolactinemia in aging populations: Prevalence, implications, prevention and management

This paper reviews the prevalence, implications, prevention and management of antipsychotic-induced hyperprolactinemia in aging populations. Antipsychotics are indicated mainly for the treatment of psychotic illness but are also used in other conditions. Complications induced by antipsychotics increase with age, due to age-related changes in drug metabolism and excretion. Almost all antipsychotics lead to hyperprolactinemia by blocking dopamine D2 receptors in the anterior pituitary gland, which counteracts dopamine's inhibitory action on prolactin secretion. The main findings of this narrative review are that, though many of the known side effects of high prolactin levels lose their salience with age, the risk of exacerbating osteoporosis remains critical. Methods of preventing antipsychotic-induced hyperprolactinemia in older individuals include using antipsychotic medication (AP) as sparingly as possible and monitoring AP serum levels, regularly measuring prolactin levels, closely monitoring bone density, treating substance abuse, and teaching patients stress management techniques. When hyperprolactinemia symptoms cannot be otherwise managed, adjunctive drugs are available. Potential helpful adjuncts are: dopamine agonists, antipsychotics with partial agonist properties (e.g. aripiprazole), selective estrogen receptor modulators, and metformin. Because a gold standard for prevention/treatment has not been established, clinical decisions need to be made based on safety and individual circumstance.

Adjunctive aripiprazole for antipsychotic-related hyperprolactinaemia in patients with first-episode schizophrenia: a meta-analysis

Background

Hyperprolactinaemia is a common antipsychotic (AP)-induced adverse effect, particularly in female patients.

Aims

This meta-analysis examined the efficacy and safety of adjunctive aripiprazole in preventing AP-related hyperprolactinaemia in patients with first-episode schizophrenia.

Methods

PubMed, PsycINFO, EMBASE, Cochrane Library, WanFang and China Journal Net databases were searched to identify eligible randomised controlled trials (RCTs). Primary outcomes were the reductions of serum prolactin level and prolactin-related symptoms. Data were independently extracted by two reviewers and analysed using RevMan (V.5.3). Weighted/standardised mean differences (WMDs/SMDs)±95% CIs were reported.

Results

In the five RCTs (n=400), the adjunctive aripiprazole (n=197) and the control groups (n=203) with a mean of 11.2 weeks of treatment duration were compared. The aripiprazole group had a significantly lower endpoint serum prolactin level in all patients (five RCTs, n=385; WMD: −50.43 ng/mL (95% CI: −75.05 to −25.81), p<0.00001; I²=99%), female patients (two RCTs, n=186; WMD: −22.58 ng/mL (95% CI: −25.67 to −19.49), p<0.00001; I²=0%) and male patients (two RCTs, n=127; WMD: −68.80 ng/mL (95% CI: −100.11 to −37.49), p<0.0001). In the sensitivity analysis for the endpoint serum prolactin level in all patients, the findings remained significant (p<0.00001; I²=96%). The aripiprazole group was superior to the control group in improving negative symptoms as assessed by the Positive and Negative Syndrome Scale (three RCTs, n=213; SMD: −0.51 (95% CI: −0.79 to −0.24), p=0.0002; I²=0%). Adverse effects and discontinuation rates were similar between the two groups.

Conclusions

Adjunctive aripiprazole appears to be associated with reduced AP-induced hyperprolactinaemia and improved prolactin-related symptoms in first-episode schizophrenia. Further studies with large sample sizes are needed to confirm these findings.

The Impact of Ethinyl Estradiol on Metformin Action on Prolactin Levels in Women with Hyperprolactinemia

Background Metformin reduced prolactin levels only in women with hyperprolactinemia.

Objective The purpose of this case-control study was to compare metformin action on lactoctrope function between women receiving oral contraceptive pills and women not using hormonal contraception.

Methods The study included two groups of matched women with elevated prolactin levels and new-onset prediabetes or diabetes. The first group consisted of 20 women using oral contraceptive pills for at least 12 months before entering the study, while the second group included 20 patients not using any hormonal contraception. Over the whole study period, all women were treated with metformin (1.7–3 g daily). Circulating levels of glucose, insulin, prolactin, thyrotropin, free thyroid hormones, adrenocorticotropic hormone, gonadotropins and insulin-like growth factor-1 were measured at the beginning and at the end of the study (16 weeks later).

Results Thirty-eight patients completed the study. Metformin reduced plasma glucose levels and improved insulin sensitivity but the latter effect was stronger in women receiving oral contraceptive pills than in women not using any contraception. Although metformin treatment decreased plasma prolactin levels in both study groups, this effect was stronger in women taking oral contraceptive pills. Only in this group of women, metformin increased plasma luteinizing hormone levels. The changes in plasma prolactin correlated with their baseline insulin sensitivity and the effect of metformin on insulin sensitivity. Metformin did not affect plasma levels of thyrotropin, free thyroxine, free triiodothyronine, follicle-stimulating hormone, adrenocorticotropic hormone and insulin-like growth factor-1.

Conclusions The obtained results suggest that the effect of metformin on overactive lactotropes depends on estrogen levels.

Stress-Induced Hyperprolactinemia: Pathophysiology and Clinical Approach

While prolactin is most well known for its role in lactation and suppression of reproduction, its physiological functions are quite diverse. There are many etiologies of hyperprolactinemia, including physiologic as well as pathologic causes. Physiologic causes include pregnancy, lactation, sleep-associated, nipple stimulation and sexual orgasm, chest wall stimulation, or trauma. Stress is also an important physiologic cause of hyperprolactinemia, and its clinical significance is still being explored. This review will provide an overview of prolactin physiology, the role of stress in prolactin secretion, as well as the general clinical approach to hyperprolactinemia.

Adjunctive Peony-Glycyrrhiza decoction for antipsychotic-induced hyperprolactinaemia: a meta-analysis of randomised controlled trials

BACKGROUND

Hyperprolactinaemia is a common adverse effect of antipsychotics (APs). The results of Peony-Glycyrrhiza decoction (PGD) as a potentially useful adjunctive treatment for hyperprolactinaemia are inconsistent.

AIM

This meta-analysis of randomised controlled trials (RCTs) examined the efficacy and safety of adjunctive PGD therapy for AP-induced hyperprolactinaemia.

METHODS

English (PubMed, Embase, Cochrane Library, PsycINFO) and Chinese (Chinese National Knowledge Infrastructure, Wanfang Data) databases were systematically searched up to 10 June 2018. The inclusion criteria were based on PICOS-Participants: adult patients with schizophrenia; Intervention: PGD plus APs; Comparison: APs plus placebo or AP monotherapy; Outcomes: efficacy and safety; Study design: RCTs. The weighted mean difference (WMD) and risk ratio (RR) along with their 95% CIs were calculated using Review Manager (RevMan) V.5.3 software.

RESULTS

Five RCTs (n=450) were included and analysed. Two RCTs (n=140) were double-blind and four RCTs (n=409) reported 'random' assignment with specific description. The PGD group showed a significantly lower serum prolactin level at endpoint than the control group (n=380, WMD: -32.69  ng/mL (95%  CI -41.66 to 23.72), p<0.00001, I 2 =97%). Similarly, the superiority of PGD over the control groups was also found in the improvement of hyperprolactinaemia-related symptoms. No difference was found in the improvement of psychiatric symptoms assessed by the Positive and Negative Syndrome Scale (n=403, WMD: -0.62 (95% CI -2.38 to 1.15), p=0.49, I 2 =0%). There were similar rates of all-cause discontinuation (n=330, RR 0.93 (95% CI 0.63 to 1.37), p=0.71, I 2 =0%) and adverse drug reactions between the two groups. According to the Grading of Recommendations Assessment, Development and Evaluation approach, the level of evidence of primary and secondary outcomes ranged from 'very low' (14.3%), 'low' (42.8%), 'moderate' (14.3%), to 'high' (28.6%).

CONCLUSIONS

Current evidence supports the adjunctive use of PGD to suppress elevated prolactin and improve prolactin-induced symptoms without significant adverse events in adult patients with AP-induced hyperprolactinaemia. High-quality RCTs with longer duration are needed to confirm these findings.

TRIAL REGISTRATION NUMBER

42016037017.

Effect of Peony-Glycyrrhiza Decoction on Amisulpride-Induced Hyperprolactinemia in Women with Schizophrenia: A Preliminary Study

Objective

The aim of this study is to observe the effect of Peony-Glycyrrhiza Decoction (PGD) on hyperprolactinemia in women with schizophrenia induced by Amisulpride.

Material and Methods

A total of 41 female schizophrenia patients receiving Amisulpride were randomly divided into placebo (n = 20) and PGD groups (n = 21). Maintaining the original Amisulpride dose, the two groups were given placebo and PGD, respectively. The levels of Prolactin (PRL) and other hormones were measured on the initial day and at weeks 4 and 8 after treatment. Changes of clinical symptoms in patients with hyperprolactinemia were observed. The PANSS scores were recorded to assess the psychotic symptoms.

Results

Compared with placebo group, level of PRL decreased while Progesterone increased remarkably in the PGD group at weeks 4 and 8 (p < 0.01), and level of Estradiol in the PGD group increased significantly at week 8 (p < 0.05). There were no differences in PANSS scores and biochemical indexes between two groups at weeks 4 and 8.

Conclusion

PGD can improve symptoms of hyperprolactinemia and hormone levels in women with schizophrenia caused by Amisulpride, without affecting their mental symptoms and biochemical indexes.

Antipsychotic-induced hyperprolactinemia: synthesis of world-wide guidelines and integrated recommendations for assessment, management and future research

RATIONALE

Hyperprolactinemia is a highly prevalent adverse effect of many antipsychotic agents, with potentially serious health consequences. Several guidelines have been developed for the management of this condition; yet, their concordance has not been evaluated.

OBJECTIVES

The objectives of this paper were (1) to review current clinical guidelines; (2) to review key systematic evidence for management; and (3) based on our findings, to develop an integrated management recommendation specific to male and female patients who are otherwise clinically stabilised on antipsychotics.

METHODS

We performed searches of Medline and EMBASE, supplemented with guideline-specific database and general web searches, to identify clinical guidelines containing specific recommendations for antipsychotic-induced hyperprolactinemia, produced/updated 01/01/2010-15/09/2016. A separate systematic search was performed to identify emerging management approaches described in reviews and meta-analyses published ≥ 2010.

RESULTS

There is some consensus among guidelines relating to baseline PRL screening (8/12 guidelines), screening for differential diagnosis (7/12) and discontinuing/switching PRL-raising agent (7/12). Guidelines otherwise diverge substantially regarding most aspects of screening, monitoring and management (e.g. treatment with dopamine agonists). There is an omission of clear sex-specific recommendations. Systematic literature on management approaches is promising; more research is needed. An integrated management recommendation is presented to guide sex-specific clinical response to antipsychotic-induced hyperprolactinemia. Key aspects include asymptomatic hyperprolactinemia monitoring and fertility considerations with PRL normalisation.

CONCLUSION

Further empirical work is key to shaping robust guidelines for antipsychotic-induced hyperprolactinemia. The integrated management recommendation can assist clinician and patient decision-making, with the goal of balancing effective psychiatric treatment while minimising PRL-related adverse health effects in male and female patients.

Adjunctive metformin for antipsychotic-related hyperprolactinemia: A meta-analysis of randomized controlled trials

Hyperprolactinemia is a common and severe antipsychotic-induced adverse drug reaction. This meta-analysis of randomized controlled trials systematically examined the efficacy and safety of adjunctive metformin for antipsychotic-related hyperprolactinemia in schizophrenia patients. Two independent investigators searched, extracted, and synthesized data. Weighted mean differences and risk ratios with their 95% confidence intervals were calculated using random effect model. Four randomized controlled trials ( n=509) comparing adjunctive metformin ( n=253) with the control groups ( n=256), lasting 22.7 weeks of treatment, were included in the meta-analysis. The metformin group had significantly lower serum prolactin level at endpoint (four randomized controlled trials, n=501; weighted mean difference: -6.87 ug/L (95% confidence interval: -13.24 to -0.51), p=0.03; I²⁼80%) with "moderate quality" based on the grading of recommendations assessment, development, and evaluation system. In patients with menstrual disturbances, the rate of menstruation resumption was 66.7% in the metformin group and 4.8% in the control group. Adverse drug reactions and all-cause discontinuation (three randomized controlled trials, n=339, risk ratio: 0.76 (95% confidence interval: 0.29, 1.97), p=0.57; I²= 0%) were similar between the two groups. Adjunctive metformin appears to be effective and safe for reducing antipsychotic-induced hyperprolactinemia and prolactin-related symptoms in schizophrenia patients. Higher quality randomized controlled trials with a large sample size are warranted to confirm these findings.

Metformin; a review of its history and future: from lilac to longevity

Metformin is a widely prescribed medication that has been used to treat children with type 2 diabetes in the United States for the past 15 years. Metformin now has a variety of clinical applications in pediatrics, and its potential clinical uses continue to expand. In addition to reviewing the current understanding of its mechanisms of action including the newly discovered effects on the gastrointestinal tract, we will also discuss current clinical uses in pediatrics, including in type 1 diabetes. Finally, we examine the existing state of monitoring for metformin efficacy and side effects and discuss prospective future clinical uses.

Efficacy and Safety of Adjunctive Aripiprazole in Schizophrenia: Meta-Analysis of Randomized Controlled Trials

This meta-analysis of randomized controlled trials (RCTs) evaluated the efficacy and safety of adding aripiprazole to other antipsychotics in schizophrenia. A systematic computer search identified 55 RCTs including 4457 patients who were randomized to aripiprazole (14.0 ± 7.0 mg/d) versus placebo (18 RCTs) or open antipsychotic treatment (37 RCTs). Aripiprazole significantly outperformed the comparison interventions based on psychiatric scales: (1) total score in 43 RCTs (N = 3351) with a standardized mean difference (SMD) of -0.48 (95% confidence interval [CI], -0.68 to -0.28; P < 0.00001; I = 88%), (2) negative symptom score in 30 RCTs (N = 2294) with an SMD of -0.61(95% CI, -0.91 to -0.31; P < 0.00001; I = 91%), and (3) general psychopathology score in 13 RCTs (N = 1138) with a weighted mean difference (WMD) of -4.02 (95% CI, -7.23 to -0.81; P = 0.01; I = 99%), but not in positive symptoms in 29 RCTs (N = 2223) with a SMD of -0.01 (95% CI, 0.26 to 0.25; P = 0.95; I = 88%). Differences in total score based on psychiatric scales may be explained by the use of an antipsychotic for comparison rather than placebo in 31 RCTs with a nonblind design. Aripiprazole outperformed the comparison interventions for body weight in 9 RCTs (N = 505) with a WMD of -5.08 kg (95% CI, -7.14 to -3.02; P < 0.00001; I = 35%) and for body mass index (BMI) in 14 RCTs (N = 809) with a WMD of -1.78 (CI: -2.25 to -1.31; P < 0.00001; I = 54%). The BMI meta-regression analysis indicated aripiprazole's association with lower BMI was stronger in females. Adjunctive aripiprazole appears safe but better RCTs are needed to demonstrate efficacy. Chinese journals and scientific societies should encourage the publication of high-quality RCTs and require registration in a centralized Chinese database.

Sex-dependent effect of metformin on hypothalamic-pituitary-thyroid axis activity in patients with subclinical hypothyroidism

BACKGROUND

Metformin was found to reduce elevated serum thyrotropin levels. No previous study has compared the effect of this drug on serum levels of thyrotropin and thyroid hormones between men and women.

METHODS

The study included 23 women and 12 men with subclinical hypothyroidism, who because of coexisting diabetes or impaired fasting glucose were treated with metformin (1.7-3.0g daily). Fasting plasma glucose levels, the homeostatic model assessment 1 of insulin resistance ratio (HOMA1-IR), glycated hemoglobin, serum levels of thyrotropin, free and total thyroid hormones and prolactin, as well as thyroid peroxidase and thyroglobulin antibodies were assessed at baseline and after 4 months of metformin treatment.

RESULTS

Baseline serum levels of thyrotropin, free thyroxine and free triiodothyronine, as well as a percentage of patients with positive thyroid peroxidase and thyroglobulin antibodies were comparable in both sexes. Metformin treatment reduced plasma glucose and insulin resistance, irrespective of the gender. However, only in women, metformin decreased serum thyrotropin levels. Neither in men nor in women, metformin affected serum levels of thyroid hormone and prolactin, as well as in the subgroups of patients with thyroiditis thyroid antibody titers.

CONCLUSIONS

The obtained results suggest that sex may determine the effect of metformin on hypothalamic-pituitary-thyroid axis activity.