Treatment of hyperprolactinaemia reduces total cholesterol and LDL in patients with prolactinomas

Dopamine D2 receptor antagonist counteracts hyperglycemia and insulin resistance in diet-induced obese male mice

Obesity leads to insulin resistance (IR) and type 2 diabetes. In humans, low levels of the hormone prolactin (PRL) correlate with IR, adipose tissue (AT) dysfunction, and increased prevalence of T2D. In obese rats, PRL treatment promotes insulin sensitivity and reduces visceral AT adipocyte hypertrophy. Here, we tested whether elevating PRL levels with the prokinetic and antipsychotic drug sulpiride, an antagonist of dopamine D2 receptors, improves metabolism in high fat diet (HFD)-induced obese male mice. Sulpiride treatment (30 days) reduced hyperglycemia, IR, and the serum and pancreatic levels of triglycerides in obese mice, reduced visceral and subcutaneous AT adipocyte hypertrophy, normalized markers of visceral AT function (PRL receptor, Glut4, insulin receptor and Hif-1α), and increased glycogen stores in skeletal muscle. However, the effects of sulpiride reducing hyperglycemia were also observed in obese prolactin receptor null mice. We conclude that sulpiride reduces obesity-induced hyperglycemia by mechanisms that are independent of prolactin/prolactin receptor activity. These findings support the therapeutic potential of sulpiride against metabolic dysfunction in obesity.

Metabolic and inflammatory parameters in relation to baseline characterization and treatment outcome in patients with prolactinoma: insights from a retrospective cohort study at a single tertiary center

Background

Prolactinomas (PRLs) are prevalent pituitary adenomas associated with metabolic changes and increased cardiovascular morbidity. This study examined clinical, endocrine, metabolic, and inflammatory profiles in PRL patients, aiming to identify potential prognostic markers.

Methods

The study comprised data from 59 PRL patients gathered in a registry at the University Hospital of Zurich. Diagnostic criteria included MRI findings and elevated serum prolactin levels. We assessed baseline and follow-up clinical demographics, metabolic markers, serum inflammation-based scores, and endocrine parameters. Treatment outcomes were evaluated based on prolactin normalization, tumor shrinkage, and cabergoline dosage.

Results

The PRL cohort exhibited a higher prevalence of overweight/obesity, prediabetes/diabetes mellitus, and dyslipidemia compared to the general population. Significant correlations were found between PRL characteristics and BMI, HbA1c, and fT4 levels. Follow-up data indicated decreases in tumor size, tumor volume, prolactin levels, and LDL-cholesterol, alongside increases in fT4 and sex hormones levels. No significant associations were observed between baseline parameters and tumor shrinkage at follow-up. A positive association was noted between PRL size/volume and the time to achieve prolactin normalization, and a negative association with baseline fT4 levels.

Conclusion

This study underscores the metabolic significance of PRL, with notable correlations between PRL parameters and metabolic indices. However, inflammatory markers were not significantly correlated with patient stratification or outcome prediction. These findings highlight the necessity for standardized follow-up protocols and further research into the metabolic pathogenesis in PRL patients.

Dance/movement therapy for improving metabolic parameters in long-term veterans with schizophrenia

Accumulating evidence has supported the implementation of dance/movement therapy (DMT) as a promising intervention for patients with schizophrenia (SCZ). However, its effect on body weight and metabolic profile in SCZ remains unclear. This study aimed to evaluate the outcome of a 12-week DMT session on weight and lipid profile in patients with SCZ using a randomized, single-blinded, controlled trial design. This study encompassed two groups of long-term hospitalized patients with SCZ, who were randomly assigned to the DMT intervention (n = 30) or the treatment as usual (TAU) group (n = 30). Metabolic markers, including weight, body mass index (BMI), fasting glucose, triglycerides, and total cholesterol were measured in both groups at two measurement points (at baseline and the end of the 12-week treatment). We found that DMT intervention significantly decreased body weight (F = 5.5, p = 0.02) and BMI (F = 5.7, p = 0.02) as compared to the TAU group. However, no significance was observed in other metabolic markers, including fasting glucose, triglycerides, and total cholesterol after treatment (all p > 0.05). Our study indicates that a 12-week, 24-session DMT program may be effective in decreasing body weight and BMI in long-term hospitalized patients with SCZ. DMT intervention may be a promising treatment strategy for long-term inpatients in the psychiatric department.

Improvement of metabolic syndrome and its components in patients who underwent transsphenoidal resection for pituitary adenoma

BACKGROUND

Pituitary adenomas (PA) are neoplasms of pituitary adenohypophyseal cell lineage, which are the third most common cause of brain tumors among adults. Due to hormone secretion, PAs are closely related to metabolic syndrome (MetS). However, the relationship between these two entities has been scarcely studied to date.

PURPOSE

This paper aims to evaluate changes in the metabolic status of patients with PA before and after surgical treatment and to look for differences in metabolic outcomes among patients according to the adenoma type and the surgery success rate.

METHODS

We assessed patients with PA who went through transsphenoidal surgery for its treatment, documenting metabolic parameters before and after surgery, analyzed whole sample changes, and then stratified them according to adenoma type (nonfunctioning, somatotroph, lactotroph, and corticotroph), and surgery success (total resection, near-total resection, partial resection, subtotal resection).

RESULTS

A total of 214 patients were enrolled for this study. The prevalence of MetS with AACE criteria went from 51.52% before surgery to 28.99% after surgery (P < 0.001). Hyperglycemia (HG) was the most beneficial component; it went from 56% pre-surgery to 40.51% post-surgery (P = 0.03). The total resection group had the best improvement, with a significant decrease of prevalence in MetS from 83 to 16% (P < 0.001), and every component, except hypoalphalipoproteinemia (HA): obesity went from 96 to 67% (P < 0.001), arterial hypertension (AH) 59 to 24% (P < 0.001), HG 74 to 23% (P < 0.001), and hypertriglyceridemia (HTG) from 81 to 54% (P < 0.001). According to MetS prevalence, there was no difference in the improvement according to PA type.

CONCLUSION

Surgical treatment in patients with PA is associated with MetS improvement.

Metabolic Syndrome Components in Patients with Pituitary Adenoma

Pituitary adenomas are benign tumors of the anterior portion of the pituitary gland (adenohypophysis), representing the 25% of all the tumor alterations. Pituitary adenomas are classified by the type of hormone secreted, cellularity, size, and structural alterations by the hormonal segregation. The diagnosis consists on the histopathological identification of cell types and the image-guided by magnetic resonance or tomography; the treatment can be both pharmacological and surgical. Metabolic Syndrome is the set of clinical conditions that increase the risk of cardiovascular diseases with an estimated prevalence of 25% worldwide. The alterations of metabolic syndrome are obesity, hypertension, dyslipidemia, insulin resistance, and diabetes mellitus type II. Pituitary adenomas and metabolic syndrome have an important relationship, hormone-secreting by pituitary adenomas affects a myriad of signaling pathways, which allows a favorable environment for the appearance of the metabolic syndrome. Moreover, patients with pituitary adenomas are shown to have an improvement in metabolic parameters after the medical/surgical treatment. The objective of this review is to explore the possible mechanisms through which PAs contributes to MetSx.

Comparative and Predictive Analysis of Clinical and Metabolic Features of Anorexia Nervosa and Bulimia Nervosa

Background

Eating disorders have become increasingly prevalent over the years; the age at which they appear has decreased, and they can lead to serious illness or death. Therefore, the number of studies on the matter has increased. Eating disorders like anorexia nervosa (AN) and bulimia nervosa (BN) are affected by many factors including mental illnesses that can have serious physical and psychological consequences. Accordingly, the present study aimed to compare the clinical and metabolic features of patients with AN and BN and identify potential biomarkers for distinguishing between the two disorders.

Methods

Clinical data of 41 participants who sought treatment for eating disorders between 2012 and 2022, including 29 AN patients and 12 BN patients, were obtained from NPIstanbul Brain Hospital in Istanbul, Turkey. The study included the clinical variables of both outpatient and inpatient treatments. Principal component analysis (PCA) was utilized to gain insights into differentiating AN and BN patients based on clinical characteristics, while machine learning techniques were applied to identify eating disorders.

Findings

The study found that thyroid hormone levels in patients with AN and BN were influenced by non-thyroidal illness syndrome (NTIS), which could be attributed to various factors, including psychiatric disorders, substance abuse, and medication use. Lipid profile comparisons revealed higher triglyceride levels in the BN group (P<0.05), indicating increased triglyceride synthesis and storage as an energy source. Liver function tests showed lower levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in BN patients (P<0.05), while higher prolactin levels (P<0.05) suggested an altered hypothalamic-pituitary-gonadal axis. Imbalances in minerals such as calcium and magnesium (P<0.05) were observed in individuals with eating disorders. PCA effectively differentiated AN and BN patients based on clinical features, and the Naïve Bayes (NB) model showed promising results in identifying eating disorders.

Conclusion

The findings of the study provide important insights into AN and BN patients' clinical features and may help guide future research and treatment strategies for these conditions.

Approach to the Patient With Prolactinoma

Prolactinomas are the most common pituitary tumor histotype, with microprolactinomas being prevalent in women and macroprolactinomas in men. Hyperprolactinemia is among the most common causes of hypogonadotropic hypogonadism in both sexes, prompting medical advice for hypogonadism (infertility, oligo-amenorrhea, impotence, osteoporosis/osteopenia) in both sexes, and for signs and symptoms of mass effects (hypopituitarism, visual loss, optic chiasm compression, cranial nerve deficits, headaches) predominantly in men. Diagnostic workup involves a single prolactin measurement and pituitary imaging, but some laboratory artifacts (ie, the "hook effect" and macroprolactin) can complicate or delay the diagnosis. The treatment of choice for prolactinomas is represented by dopamine agonists, mainly cabergoline, which are able to induce disease control, restore fertility in both sexes, and definitively cure one-third of patients, thus permitting treatment discontinuation. Pregnancy and menopause may promote spontaneous prolactin decline and anticipate cabergoline discontinuation in women. Surgery and/or radiotherapy are indicated in case of resistance to cabergoline not overcome by the increase in drug dose up to the maximally tolerated or the patient's personal choice of surgery. The evidence of resistance to cabergoline in invasive and proliferative tumors may indicate biological aggressiveness, thus requiring alternative therapeutic approaches mainly based on temozolomide use as monotherapy or combined with radiotherapy. In uncontrolled patients, new medical approaches (alternative hormonal treatments, cytotoxic drugs, peptide receptor radionuclide therapy, mTOR/Akt inhibitors, tyrosine kinase inhibitors, or immunotherapy) may be offered but the experience collected to date is still very scant. This article reviews different facets of prolactinomas and discusses approaches to the condition in more common clinical situations.

Metabolic effects of dopamine-agonists treatment among patients with prolactinomas

PURPOSE

To evaluate the effect of cabergoline treatment on metabolic parameters including the Triglyceride-glucose (TyG) index in newly diagnosed patients with prolactinoma.

METHODS

71 consecutive nondiabetic patients with prolactinoma were enrolled. Anthropometric and laboratory tests including TyG index were measured at baseline, 3 and 6 months visits. Treatment with cabergoline at the dose of 0.25 mg twice weekly was started and increased according to prolactin levels and continued for 6 months.

RESULTS

At the baseline examination, the mean (SD) age, body mass index (BMI), waist circumference (WC), systolic blood pressure (SBP), and diastolic blood pressure (DBP) of patients were 36.2 (10.5) years, 29.2 (5.0) kg/m², 98.2 (13.7) cm, 115.3 (13.3) mmHg, and 71.4 (8.1) mmHg, respectively. Forty-one (57.7%) of patients were women and 46 (64.8%) had microadenoma. Cabergoline treatment significantly improved anthropometric and metabolic measures including BMI, WC, fasting plasma glucose, triglycerides, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, uric acid (only among women), TyG index, and hypogonadism. Blood pressure (both systolic and diastolic) levels remained steady except for a significant decrease in DBP after 6 months of treatment only among women. A declining trend in MetS prevalence was found from baseline to a 3-month evaluation in both genders which was statistically significant among men.

CONCLUSION

Short-term treatment with cabergoline can significantly improve cardiovascular risk factors except for blood pressure. Moreover, the TyG index as a surrogate marker of insulin resistance decreased significantly after the reduction of prolactin by treatment. Generally, results were similar among both genders.

The metabolic role of prolactin: systematic review, meta-analysis and preclinical considerations

INTRODUCTION

Hyperprolactinemia has been proven to induce hypogonadism and metabolic derangements in both genders, while the consequences of prolactin (PRL) deficiency have been poorly investigated.

AREAS COVERED

To systematically review and analyze data from clinical studies focusing on the metabolic consequences of abnormally high prolactin levels (HPRL) and low prolactin levels (LPRL). In addition, data from preclinical studies about underlying pathophysiological mechanisms were summarized and discussed.

EXPERT OPINION

PRL contributes to providing the correct amount of energy to support the mother and the fetus/offspring during pregnancy and lactation, but it also has a homeostatic role. Pathological PRL elevation beyond these physiological conditions, but also its reduction, impairs metabolism and body composition in both genders, increasing the risk of diabetes and cardiovascular events. Hence, hypoprolactinemia should be avoided as much as possible during treatment with dopamine agonists for prolactinomas. Patients with hypoprolactinemia, because of endogenous or iatrogenic conditions, deserve, as those with hyperprolactinemia, careful metabolic assessment.

25-Hydroxyvitamin D and metabolic-related laboratory values in women with schizophrenia and hyperprolactinemia

Schizophrenia is a severe mental disorder with various medical comorbidities and early mortality. Hyperprolactinemia is common in women and its impact on sexual function, galactorrhea and amenorrhea is well known. This paper evaluates the risk of 25-hydroxy vitamin D deficiency and other metabolic related laboratory abnormalities in women with schizophrenia having hyperprolactinemia (N = 43). The mean prolactin level in these women was 88.5 ± 56.0 ng/mL. We found that 100% of women were overweight of which 74% (32/43) of the women were obese, 56% (23/41) had abnormal total cholesterol levels and 30% (13/43) had high fasting blood glucose. Vitamin D levels were considered deficient or inadequate in 37% of women. We did not see significant correlations of prolactin with laboratory measures, however all female patients had elevated and high prolactin levels, leading to low variability in a small sample, which may have precluded seeing any direct relationships. Recognizing prolactin related side effects and understanding the role of other health measures seen in women with antipsychotic induced hyperprolactinemia in our female patients are critical steps toward better personalization of their care and recovery.

Crosstalk between Schizophrenia and Metabolic Syndrome: The Role of Oxytocinergic Dysfunction

The high prevalence of metabolic syndrome in persons with schizophrenia has spurred investigational efforts to study the mechanism beneath its pathophysiology. Early psychosis dysfunction is present across multiple organ systems. On this account, schizophrenia may be a multisystem disorder in which one organ system is predominantly affected and where other organ systems are also concurrently involved. Growing evidence of the overlapping neurobiological profiles of metabolic risk factors and psychiatric symptoms, such as an association with cognitive dysfunction, altered autonomic nervous system regulation, desynchrony in the resting-state default mode network, and shared genetic liability, suggest that metabolic syndrome and schizophrenia are connected via common pathways that are central to schizophrenia pathogenesis, which may be underpinned by oxytocin system dysfunction. Oxytocin, a hormone that involves in the mechanisms of food intake and metabolic homeostasis, may partly explain this piece of the puzzle in the mechanism underlying this association. Given its prosocial and anorexigenic properties, oxytocin has been administered intranasally to investigate its therapeutic potential in schizophrenia and obesity. Although the pathophysiology and mechanisms of oxytocinergic dysfunction in metabolic syndrome and schizophrenia are both complex and it is still too early to draw a conclusion upon, oxytocinergic dysfunction may yield a new mechanistic insight into schizophrenia pathogenesis and treatment.

Emerging Evidence of Pathological Roles of Very-Low-Density Lipoprotein (VLDL)

Embraced with apolipoproteins (Apo) B and Apo E, triglyceride-enriched very-low-density lipoprotein (VLDL) is secreted by the liver into circulation, mainly during post-meal hours. Here, we present a brief review of the physiological role of VLDL and a systemic review of the emerging evidence supporting its pathological roles. VLDL promotes atherosclerosis in metabolic syndrome (MetS). VLDL isolated from subjects with MetS exhibits cytotoxicity to atrial myocytes, induces atrial myopathy, and promotes vulnerability to atrial fibrillation. VLDL levels are affected by a number of endocrinological disorders and can be increased by therapeutic supplementation with cortisol, growth hormone, progesterone, and estrogen. VLDL promotes aldosterone secretion, which contributes to hypertension. VLDL induces neuroinflammation, leading to cognitive dysfunction. VLDL levels are also correlated with chronic kidney disease, autoimmune disorders, and some dermatological diseases. The extra-hepatic secretion of VLDL derived from intestinal dysbiosis is suggested to be harmful. Emerging evidence suggests disturbed VLDL metabolism in sleep disorders and in cancer development and progression. In addition to VLDL, the VLDL receptor (VLDLR) may affect both VLDL metabolism and carcinogenesis. Overall, emerging evidence supports the pathological roles of VLDL in multi-organ diseases. To better understand the fundamental mechanisms of how VLDL promotes disease development, elucidation of the quality control of VLDL and of the regulation and signaling of VLDLR should be indispensable. With this, successful VLDL-targeted therapies can be discovered in the future.

Are dopamine agonists still the first-choice treatment for prolactinoma in the era of endoscopy? A systematic review and meta-analysis

Background

For prolactinoma patients, dopamine agonists (DAs) are indicated as the first-line treatment and surgery is an adjunctive choice. However, with the development of surgical technique and equipment, the effect of surgery has improved. The aim of this study was to assess the efficacy and safety of surgery versus DAs in patients with different types of prolactinomas.

Methods

A systematic search of literature using Web of Science, PubMed, Cochrane Library, and Clinical Trial databases was conducted until July 12, 2019. Prolactinoma patients treated with DAs (bromocriptine or cabergoline) or surgery (microscopic or endoscopic surgery) were included. Outcomes included the biochemical cure rate, recurrence rate, prolactin level, improvement rates of symptoms, and incidence rates of complications. A random-effects model was used to pool the extracted data. Qualitative comparisons were conducted instead of quantitative comparison.

Results

DAs were better than surgery in terms of the biochemical cure rate (0.78 versus 0.66), but surgery had a much lower recurrence rate (0.19 versus 0.57). Full advantages were not demonstrated in improvement rates of symptoms and incidence rates of complications with both treatment options. In microprolactinoma patients, the biochemical cure rate of endoscopic surgery was equal to the average cure rate of DAs (0.86 versus 0.86) and it surpassed the biochemical cure rate of bromocriptine (0.86 versus 0.76). In macroprolactinoma patients, endoscopic surgery was slightly higher than bromocriptine (0.66 versus 0.64) in terms of the biochemical cure rate.

Conclusion

For patients with clear indications or contraindications for surgery, choosing surgery or DAs accordingly is unequivocal. However, for patients with clinical equipoise, such as surgery, especially endoscopic surgery, in microprolactinoma and macroprolactinoma patients, we suggest that neurosurgeons and endocrinologists conduct high-quality clinical trials to address the clinical equipoise quantitatively.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41016-022-00277-1.

Metabolic effects of prolactin

Over the last years, the metabolic role of PRL has emerged. PRL excess is known to promote weight gain, obesity, metabolic syndrome, and impairment in gluco-insulinemic and lipid profiles, likely due to the suppression of physiologic dopaminergic tone. Prolactin receptors and dopamine receptors type 2 have been demonstrated to be expressed on both human pancreatic β- cell and adipocytes, supporting a key role of prolactin and dopamine in peripheral metabolic regulation. Medical treatment with the dopamine agonists bromocriptine and cabergoline has been demonstrated to decrease the prevalence of metabolic syndrome and obesity, and significantly improve gluco-insulinemic and lipid profiles. In hyperprolactinemic men with concomitant hypogonadism, correction of hyperprolactinaemia and testosterone replacement has been proven to restore metabolic impairment. In turn, low prolactin levels have also been demonstrated to exert a detrimental effect on weight gain, glucose and lipid metabolism, thus leading to an increased prevalence of metabolic syndrome. Therefore, PRL values ranging from 25 to 100 mg/L, in absence of other recognizable pathological causes, have been proposed to represent a physiological response to the request for an increase in metabolic activity, and nowadays classify the so-called HomeoFIT- PRL as a promoter of metabolic homeostasis. The current review focuses mainly on the effects of hyperprolactinemia and its control by medical treatment with DAs on the modulation of food intake, body weight, gluco-insulinemic and lipid profile. Furthermore, it provides the latest knowledge about the metabolic impact of hypoprolactinemia.

The interplay between prolactin and cardiovascular disease

Hyperprolactinemia can be caused by several conditions and its effects on the hypothalamic-pituitary-gonadal axis are understood in more detail. Nevertheless, in recent decades, other metabolic effects have been studied and data pointed to a potential increased cardiovascular disease (CVD) risk. A recent study showed a decrease in total and LDL- cholesterol only in men with prolactinoma treated with dopamine agonists (DA) supporting the previous results of a population study with increased CVD risk in men harboring prolactinoma. However, other population studies did not find a correlation between prolactin (PRL) levels and CVD risk or mortality. There is also data pointing to an increase in high-density lipoprotein levels, and decreases in triglycerides, carotid-intima-media thickness, C-reactive protein, and homocysteine levels in patients with prolactinoma on DA treatment. PRL was also implicated in endothelial dysfunction in pre and postmenopausal women. Withdrawal of DA resulted in negative changes in vascular parameters and an increase in plasma fibrinogen. It has been shown that PRL levels were positively correlated with blood pressure and inversely correlated with dilatation of the brachial artery and insulin sensitivity, increased homocysteine levels, and elevated D-dimer levels. Regarding possible mechanisms for the association between hyperprolactinemia and CVD risk, they include a possible direct effect of PRL, hypogonadism, and even effects of DA treatment, independently of changes in PRL levels. In conclusion, hyperprolactinemia seems to be associated with impaired endothelial function and DA treatment could improve CVD risk. More studies evaluating CVD risk in hyperprolactinemic patients are important to define a potential indication of treatment beyond hypogonadism.

Metabolic effects of prolactin and the role of dopamine agonists: A review

Prolactin is a polypeptide hormone that is well known for its role in reproductive physiology. Recent studies highlight its role in neurohormonal appetite regulation and metabolism. Elevated prolactin levels are widely associated with worsening metabolic disease, but it appears that low prolactin levels could also be metabolically unfavorable. This review discusses the pathophysiology of prolactin related metabolic changes, and the less commonly recognized effects of prolactin on adipose tissue, pancreas, liver, and small bowel. Furthermore, the effect of dopamine agonists on the metabolic profiles of patients with hyperprolactinemia are discussed as well.

Prolactinomas

Hyperprolactinemia, defined by a level of serum prolactin above the standard upper limit of normal range, is a common finding in clinical practice and prolactinomas are the main pathological cause. Prolactinomas lead to signs and symptoms of hormone oversecretion, such as galactorrhea and hypogonadism, as well as symptoms of mass effect, including visual impairment, headaches and intracranial hypertension. Diagnosis involves prolactin measurement and sellar imaging, but several pitfalls are involved in this evaluation, which may difficult the proper management. Treatment is medical in the majority of cases, consisting of dopamine agonists, which present high response rates, with a very favorable safety profile. Major adverse effects that should be monitored consist of cardiac valvulopathy and impulse control disorders. Other treatment options include surgery and radiotherapy. Temozolomide may be used for aggressive or malignant carcinomas. Finally, pregnancy outcomes are similar to general population even when dopamine agonist treatment is maintained.

Prolactin, metabolic and immune parameters in naïve subjects with a first episode of psychosis

BACKGROUND

Prolactin (Prl) is a pleiotropic hormone initially described for its regulation of lactation in mammals but later associated with metabolic and immune homeostasis, stress, inflammatory response and human behavior. Its regulation through dopamine receptors highlights its importance in psychiatry mostly because hyperprolactinemia is a common secondary side effect of dopamine antagonists. Despite its undeciphered patho-physiological mechanisms, hyperprolactinemia in naïve psychosis patients has been widely described. Its consequences might underlie the increased morbidity and early mortality found in naïve subjects as described in the general population where prolactin values have been correlated with inflammatory, immune and metabolic parameters.

METHODS

We aimed to evaluate the correlation between prolactin values and other biochemical parameters (C-reactive Protein-CrP, blood cell count, lipid and hepatic profile, fasting glucose) in a cohort of first episode psychosis naïve subjects (N = 491) stratified by sex. Regression analyses with confounders were performed to evaluate the association.

FINDINGS

Prl displayed significant correlations with C-Reactive Protein (CrP), Low-Density Lipoprotein (LDL), Aspartate Transaminase (AST) for females and High-Density Lipoprotein (HDL) and eosinophil count for males. However, and despite previous specific sex correlations, significant associations were described for CrP, HDL, LDL, AST and ALT without sex interaction and despite confounders such as age, Body Mass Index or smoking status.

CONCLUSIONS

Our results show a specific relation of Prl with immune and metabolic parameters describing a heterogeneous pattern. Our results suggest that prolactin might underlie the excess of morbidity and early mortality in naïve patients through a specific pathway.

Impact of primary medical or surgical therapy on prolactinoma patients' BMI and metabolic profile over the long-term

•

High prolactin (PRL) levels are associated with weight gain and impaired metabolic profiles.

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Long-term control of hyperprolactinemia can be attained by first-line surgery and medical therapy.

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Normalization of PRL improves patients’ BMI and fasting glucose levels.

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Marginal changes in patients’ metabolic profiles are noted regardless of the primary therapy.

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Not dopamine agonists per se, but rather the control of hyperprolactinemia plays a role in metabolic profile alterations.

Objectives

High prolactin levels have been associated with weight gain and impaired metabolic profiles. While treatment with dopamine agonists (DAs) has been shown to improve these parameters, there is a lack of surgical series on its comparative effect in prolactinoma patients.

Methods

In this retrospective, comparative study, consecutive patients with a prolactinoma were enrolled if treated with first-line transsphenoidal surgery (TSS) or with DAs. Patients with prolactinomas of Knosp grade >2 and those with a follow-up <24 months were excluded, as were patients with missing laboratory metabolic parameters at baseline and over the long-term. Effects of either treatment on BMI and the metabolic profile were analyzed, and independent risk factors for long-term obesity were calculated.

Results

Primary treatment was TSS for 12 patients (40%) and DAs for 18 patients (60%). At diagnosis, no significant differences between the two cohorts were observed with regard to adenoma size, Knosp grading, baseline prolactin (PRL) levels, prevalence of hypogonadism, or laboratory metabolic parameters. Mean follow-up was 51.9 months (range, 24–158). Over the long-term, both TSS and DAs led to the control of hyperprolactinemia (92% vs. 72%) and hypogonadism (78% vs. 83%) in the majority of patients. While a significant decrease in patients’ BMI and fasting glucose were observed, changes in the lipid profile were marginal and independent of the treatment modality. At baseline, increased BMI—but not the primary treatment strategy—was an independent predictor of long-term obesity.

Conclusions

Over the long-term, patients’ BMI and FG improve, but changes in the metabolic profile are marginal and independent of the primary treatment. It is presumable that not DAs per se, but rather the control of hyperprolactinemia plays a role in patients’ metabolic profile alterations.

Adverse body composition and lipid parameters in patients with prolactinoma: a case-control study

BACKGROUND

Hyperprolactinaemia might cause adverse metabolic effects. The aim of our study was to compare parameters of body composition, glucose and lipid metabolism between untreated patients with prolactinoma and controls and to assess changes after initiation of cabergoline.

METHODS

Case-control study with a retrospectively analyzed follow-up in patients with prolactinoma after initiation of cabergoline therapy.

RESULTS

21 patients with prolactinoma (9 micro- and 12 macroprolactinomas; 7 females) and 30 controls were analyzed. Patients with prolactinoma had significantly higher BMI than controls; fat mass did not differ between groups. Only men - but not women - with prolactinoma had significantly higher fat mass at all six sites measured compared to controls. Levels of LDL (130 (107-147.5) vs. 94.5 (80-127.5) mg/dl, p < 0.001) were significantly higher, levels of HDL (56 ± 16.7 vs. 69.2 ± 14.6 mg/dl, p = 0.004) significantly lower than in controls. Fasting glucose, HOMA-IR, HbA1c, adiponectin, CRP, and homocysteine did not differ between groups. After a median of 10 weeks (IQR 7-18 weeks) after initiation of cabergoline, total (from 212.5 ± 36.2 to 196.9 ± 40.6 mg/dl, p = 0.018) and LDL cholesterol (130 (107-147.5) to 106.5 (94.3-148) mg/dl, p = 0.018) had significantly decreased. Analyzing men and women separately, this change occurred in men only.

CONCLUSIONS

Reasons for the association between prolactin and metabolic parameters include direct effects of prolactin on adipose tissue, hyperprolactinaemia-triggered hypogonadism and dopamine-agonist therapy per se. Altered lipid metabolism in patients with prolactinoma might imply an increased cardiovascular risk, highlighting the necessity to monitor metabolic parameters in these patients.

Association Between Prolactinoma and Body Mass Index

OBJECTIVE

Obesity is increasing worldwide, and certain endocrine disorders may contribute to weight gain. While several studies have examined the association between weight gain and prolactinomas, the results are conflicting. Therefore, this study aimed to determine if body mass index (BMI) is higher among those with prolactinomas than those without.

METHODS

We identified patients ≥18 years of age referred to an endocrine clinic between 2008 and 2018 with newly diagnosed prolactinomas. We extracted the relevant information, and comparative data was obtained from the 2015-2016 National Health and Nutrition Examination Survey.

RESULTS

In total, 34 cases met the inclusion criteria. One third of the patients described weight gain at presentation. Those with prolactinomas had a significantly higher BMI than the National Health and Nutrition Examination Survey population (median BMI, 29.8 kg/m² vs 28.3 kg/m², P = .0048). When stratified by sex, only men with prolactinomas had an increased BMI compared with the controls. Moreover, those with prolactinomas had a higher prevalence of class II obesity (BMI ≥ 35 kg/m²) than the survey population (35% vs 18%, P = .01). Among the prolactinoma patients, a correlation was observed between BMI and log-transformed prolactin levels (R² = 0.4, P = .0002).

CONCLUSION

Weight gain can be a presenting symptom for patients with newly diagnosed prolactinomas. Those with prolactinomas have a higher BMI and an increased prevalence of class II obesity. These findings suggest that patients should be counseled regarding weight issues related to prolactinomas at presentation and should be a consideration in the investigative and treatment algorithm of prolactinomas.

Carbohydrate-rich Meals Have no Impact on Post-prandial Lipid Parameters in Indians with Subclinical and Overt Primary Hypothyroidism

BACKGROUND AND AIMS

The impact of altered cholesterol metabolism on post-prandial lipids in Indians with hypothyroidism is not known. This study evaluated the impact of overt primary hypothyroidism (OPH) and subclinical hypothyroidism (ScH) on post-prandial lipids after a standardised, carbohydrate-rich, mixed meal.

METHODS

Endocrinology outpatients were screened for possible inclusion into the study. Patients >18 years of age with hypothyroidism who were not taking levothyroxine and who did not present with any comorbidities underwent biochemical evaluation following a carbohydrate-rich, mixed meal. Assessments included total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), triglycerides, lipoprotein-A (Lp-A), apolipoprotein-A1 (apo-A1), apolipoprotein-B (apo-B), insulin and fasting glucose. Assessments were carried out 1 hour, 2 hours and 4 hours after the meal. Patients were compared against healthy matched controls recruited from healthcare professionals in the hospital (asymptomatic and apparently healthy nursing staff, reception staff and ward staff).

RESULTS

Data from 194 patients (161 with ScH and 33 with OPH) and 40 euthyroid controls were analysed. Anthropometry, body mass index, glycaemia and insulin resistance were comparable among patients with OPH and ScH, and controls. LDL-C and Lp-A were significantly higher in those with OPH, compared with ScH and controls, at baseline, 1 hour, 2 hours and 4 hours after mixed meal consumption (all p<0.05). There was progressive and similar decline in post-prandial TC, LDL-C and Lp-A in all three groups. Triglycerides were similar among the OPH, ScH and control groups, both in fasting and post-prandial state, with a progressive and similar increase in post-prandial triglycerides in all three groups.

CONCLUSION

This study demonstrated that severity of hypothyroidism had no impact on post-prandial TC, LDL-C and Lp-A. In addition, hypothyroidism had no impact on post-prandial triglycerides. Therefore, we conclude that lipid profile can be reliably estimated in a non-fasting state in individuals with ScH and OPH.

Hyperprolactinaemia

Hyperprolactinaemia is one of the most common problems in clinical endocrinology. It relates with various aetiologies (physiological, pharmacological, pathological), the clarification of which requires careful history taking and clinical assessment. Analytical issues (presence of macroprolactin or of the hook effect) need to be taken into account when interpreting the prolactin values. Medications and sellar/parasellar masses (prolactin secreting or acting through “stalk effect”) are the most common causes of pathological hyperprolactinaemia. Hypogonadism and galactorrhoea are well-recognized manifestations of prolactin excess, although its implications on bone health, metabolism and immune system are also expanding. Treatment mainly aims at restoration and maintenance of normal gonadal function/fertility, and prevention of osteoporosis; further specific management strategies depend on the underlying cause. In this review, we provide an update on the diagnostic and management approaches for the patient with hyperprolactinaemia and on the current data looking at the impact of high prolactin on metabolism, cardiovascular and immune systems.

Metabolic effects of dopamine agonists in patients with prolactinomas: a systematic review and meta-analysis

OBJECTIVES

Recent large cohort studies suggest an association between high plasma prolactin and cardiovascular mortality. The objective of this systematic review was to systematically assess the effect of reducing prolactin with dopamine agonist on established cardiovascular risk factors in patients with prolactinomas.

DESIGN

Bibliographical search was done until February 2019 searching the following databases: PubMed, EMBASE, WHO and LILAC. Eligible studies had to include participants with verified prolactinomas where metabolic variables were assessed before and after at least 2 weeks treatment with dopamine agonists.

METHODS

Baseline data and outcomes were independently collected by two investigators. The study was registered with PROSPERO (registration number CRD42016046525).

RESULTS

Fourteen observational studies enrolling 387 participants were included. The pooled standardized mean difference of the primary outcome revealed a reduction of BMI and weight of -0.21 (95% CI -0.37 to -0.05; P = 0.01; I2 = 71%), after treatment. Subgroup analysis suggested that the reduction of weight was primarily driven by studies with high prolactin levels at baseline (P = 0.04). Secondary outcomes suggested a small decrease in waist circumference, a small-to-moderate decrease in triglycerides, fasting glucose levels, HOMA-IR, HbA1c and hsCRP, and a moderate decrease in LDL, total cholesterol and insulin.

CONCLUSION

This systematic review suggests a reduction of weight as well as an improved lipid profile and glucose tolerance after treatment with dopamine agonist in patients with prolactinomas. These data are based on low-quality evidence.

The effects of hyperprolactinemia and its control on metabolic diseases

INTRODUCTION

Hyperprolactinaemia has been implicated in the pathogenesis of obesity and glucose intolerance and is reportedly associated with impaired metabolic profile and metabolic syndrome in approximately one third of patients.

AREAS COVERED

Suppression of dopaminergic tone has been proposed as a potential mechanism responsible for weight gain and metabolic abnormalities in such patients. Dopamine receptor type 2 (D₂R) is abundantly expressed on human pancreatic β-cell and adipocytes, suggesting a regulatory role for peripheral dopamine in insulin and adipose functions. Medical treatment with the dopamine-agonists bromocriptine and cabergoline has been shown to significantly improve gluco-insulinemic and lipid profile, also reducing the prevalence of metabolic syndrome. In patients with concomitant hypogonadism, simultaneous correction of both PRL excess and testosterone deficiency is mandatory to improve insulin resistance and metabolic abnormalities.

EXPERT COMMENTARY

Hyperprolactinemia promotes metabolic alterations. Control of PRL excess by dopamine agonists is mandatory to induce weight loss and to improve metabolic profile, and replacement treatment for concomitant hypogonadism effectively ameliorates insulin resistance and metabolic syndrome.