Hyperprolactinemia after menopause: Diagnosis and management

The Influence of Concurrent Autoimmune Thyroiditis on the Cardiometabolic Consequences of Cabergoline in Postmenopausal Women

Background: Untreated hyperprolactinemia and autoimmune thyroiditis (Hashimoto's disease) seem to increase cardiometabolic risk. The cardiometabolic effects of cabergoline were less significant in young women with concurrent euthyroid Hashimoto's illness. This study sought to investigate if the detrimental effects of this condition on cabergoline efficacy are also evident in postmenopausal women. Methods: The study comprised 50 postmenopausal women exhibiting increased prolactin levels, with half qualifying for euthyroid Hashimoto's illness. The subjects with thyroid autoimmunity were matched with those without thyroid disease according to age, body mass index, and prolactin levels. In addition to prolactin, we assessed thyroid-stimulating hormone (TSH), thyroid antibodies, and glucose homeostasis markers: fasting glucose, the homeostatic model assessment 1 of insulin resistance ratio (HOMA1-IR), and glycated hemoglobin (HbA1c). Furthermore, we assessed plasma lipids, plasma uric acid levels, high-sensitivity C-reactive protein (hsCRP), fibrinogen, homocysteine, and the urine albumin-to-creatinine ratio (UACR). The decadal cardiovascular risk was assessed with the Framingham Risk Score (FRS). Results: Before therapy, disparities existed among groups in HOMA1-IR, HDL cholesterol, antibody titers, uric acid, hsCRP, fibrinogen, homocysteine, UACR, and FRS. After six months of treatment, cabergoline successfully corrected prolactin levels (both total and monomeric) in women without thyroid disorders. This normalization correlated with decreases in HOMA1-IR, triglycerides, uric acid, hsCRP, fibrinogen, homocysteine, UACR, and FRS, as well as an elevation in HDL cholesterol. In women diagnosed with Hashimoto's disease, cabergoline's effects were limited to a reduction in prolactin levels, HOMA1-IR, and UACR, as well as an elevation in HDL cholesterol, with these alterations being less pronounced compared to women without thyroid illness. Conclusions: The cardiometabolic benefits of cabergoline were associated with the degree of prolactin concentration reduction. In women diagnosed with Hashimoto's disease, connections were noted between baseline levels and treatment-induced alterations in hsCRP. These data indicate that concurrent euthyroid autoimmune thyroiditis mitigates the cardiometabolic consequences of cabergoline.

Modern approach to bone comorbidity in prolactinoma

Prolactinomas account for more than half of pituitary adenomas, and besides their clinical impact on fertility and gonadal function, they lead to detrimental effects on bone. Patients with prolactinoma are prone to deterioration of bone structure caused not only by prolactin (PRL) induced hypogonadism but also by its direct actions on bone cells and calcium metabolism. However, clinical studies have shown inconsistent evidence regarding whether PRL could have a deleterious effect independently from gonadal insufficiency on skeletal integrity. Seminal studies from our group reported an increased prevalence of vertebral fractures (VFs) in both female and male patients with prolactinoma. Treatment of prolactinoma with dopamine agonists can restore gonadal function and improve bone mineral density. Since the presence of VFs may be related to more aggressive disease, bone comorbidities in prolactinoma should be managed by a multidisciplinary team in line with the recent concept of 'pituitary tumors centers of excellence'. The review aims to evaluate the mechanism of PRL actions on bone, as well as to provide practical indications for a modern approach to the management of skeletal complications of patients with prolactin-secreting adenoma considering different clinical characteristics and outcomes.

Prolactin Role in COVID-19 and Its Association with the Underlying Inflammatory Response

The COVID-19 pandemic has prompted interest in identifying reliable biomarkers to predict disease severity and guide clinical decisions. Prolactin (PRL), a hormone traditionally associated with lactation, has gained attention for its role in immune modulation. This study aimed to assess PRL as a biomarker for disease severity in COVID-19. A prospective cohort of 142 patients with moderate to severe COVID-19, defined as a WHO-CPS 5 or 6, was recruited from the University General Hospital of Patras. Baseline PRL levels were measured using an electrochemiluminescence immunoassay, and serum cytokines, including IL-1β, IL-6, IL-8, IL-10, IL-12p70, and TNF-α, were quantified through flow cytometry. Clinical outcomes, including mortality and the need for invasive mechanical ventilation (IMV), were recorded. Results indicated that PRL levels were significantly higher in female patients (12.95 ng/mL vs. 9.40 ng/mL, p < 0.001) but they did not correlate with key severity indices such as CCI, SOFA score upon admission or inflammatory markers. No significant associations between baseline PRL levels, cytokine concentrations, and clinical outcomes in COVID-19 were noted. Our findings suggest that PRL may lack prognostic reliability for disease severity compared to more established predictive markers and that its role in the immune response remains uncertain.

Treatment of hyperprolactinemia in women: A Position Statement from the Brazilian Federation of Gynecology and Obstetrics Associations (Febrasgo) and the Brazilian Society of Endocrinology and Metabolism (SBEM)

Dopamine agonists are the first line of treatment for patients with symptomatic hyperprolactinemia due to prolactinomas and in those with idiopathic hyperprolactinemia. Treatment with these agents is effective in 80%-90% of the cases. Infertility treatment of patients with hyperprolactinemia is also carried out with dopamine agonists, aiming for the normalization of prolactin levels. The risk of symptomatic growth of prolactinomas during pregnancy is dependent on the tumor's size, duration of previous treatments, and prolactin levels. Notably, the corresponding risk is relatively low in cases of microprolactinomas (<5%). Remission of hyperprolactinemia occurs in about 30% of the patients after drug treatment and may also occur after pregnancy and menopause. The use of some drugs, such as antidepressants and antipsychotics, is a frequent cause of hyperprolactinemia, and managing this occurrence involves unique considerations. This position statement by the Brazilian Federation of Gynecology and Obstetrics Associations (Febrasgo) and Brazilian Society of Endocrinology and Metabolism (SBEM) addresses the recommendations for measurement of serum prolactin levels and the investigations of symptomatic and asymptomatic hyperprolactinemia and drug-induced hyperprolactinemia in women.

Diagnosis of hyperprolactinemia in women: A Position Statement from the Brazilian Federation of Gynecology and Obstetrics Associations (Febrasgo) and the Brazilian Society of Endocrinology and Metabolism (SBEM)

Hyperprolactinemia is a frequent cause of menstrual irregularity, galactorrhea, hypogonadism, and infertility. The most common etiologies of hyperprolactinemia can be classified as physiological, pharmacological, and pathological. Among pathological conditions, it is essential to distinguish prolactinomas from other tumors and pituitary lesions presenting with hyperprolactinemia due to pituitary stalk disconnection. Proper investigation considering clinical data, laboratory tests, and, if necessary, imaging evaluation, is important to identify the correctcause of hyperprolactinemia and manage the patient properly. This position statement by the Brazilian Federation of Gynecology and Obstetrics Associations (Febrasgo) and Brazilian Societyof Endocrinology and Metabolism (SBEM) addresses the recommendations for measurement of serum prolactin levels and the investigations of symptomatic and asymptomatic hyperprolactinemia and medication-induced hyperprolactinemia in women.

Prolactinoma in postmenopausal women: a systematic review

IMPORTANCE

Prolactinomas occurring during the reproductive period exhibit a characteristic behavior. There are, however, gaps in the literature regarding the behavior of these tumors after menopause.

OBJECTIVE

This study aimed to review and characterize the influence of menopause on prolactinoma behavior.

EVIDENCE REVIEW

A systematic review of observational prospective or retrospective studies and clinical trials on prolactinomas was conducted in two situations: tumors diagnosed in the reproductive period (before menopause), with follow-up in the postmenopausal period, or prolactinomas diagnosed in the postmenopausal period, without language or date restrictions. Data extracted from the articles included patient and tumor characteristics (prolactinoma type, previous treatment, symptoms, and serum prolactin [PRL] levels).

FINDINGS

This study included five studies comprising 180 participants. Prolactinomas diagnosed in women of reproductive age are treated with dopaminergic agonists (DAs), with indications of treatment withdrawal after menopause, exhibited stable tumor behavior and PRL levels. Considering the diagnosis during the postmenopausal period, macroprolactinomas were more prevalent and showed tumor shrinkage when DAs were used. Cabergoline, the most commonly used drug, lowers PRL levels and reduces symptoms associated with adenoma.

CONCLUSIONS AND RELEVANCE

Microadenomas diagnosed before menopause can be followed up without treatment. Prolactinomas diagnosed after menopause are typically macroadenomas. Cabergoline remains the treatment of choice in the presence of clinical or compressive symptoms. We recommend at least one annual follow-up for such patients.

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.

New tools for bone health assessment in secreting pituitary adenomas

Pituitary hormones regulate skeletal physiology, and excess levels affect bone remodeling and alter bone microstructure. Vertebral fractures (VFs) are an early phenomenon of impaired bone health in secreting pituitary adenomas. However, they are not accurately predicted by areal bone mineral density (BMD). Emerging data demonstrate that a morphometric approach is essential for evaluating bone health in this clinical setting and is considered to be the gold standard method in acromegaly. Several novel tools have been proposed as alternative or additional methods for the prediction of fractures, particularly in pituitary-driven osteopathies. This review highlights the novel potential biomarkers and diagnostic methods for bone fragility, including their pathophysiological, clinical, radiological, and therapeutic implications in acromegaly, prolactinomas, and Cushing's disease.

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.