Cabergoline can induce mania with psychotic features in bipolar I disorder: a case report

Neuropsychiatric Effects in Patients With Invasive Prolactinomas Treated With Cabergoline

Background and objective Invasive prolactinoma accounts for 1-5% of all prolactinomas. Its mass and compromise of the diencephalon and frontal and temporal lobes may result in a range of neuropsychiatric symptoms that are often missed during initial evaluations. Cabergoline is a dopaminergic agonist used as the first-line treatment for these patients; however, its effect on neuropsychiatric symptoms in this particular setting remains unexplored. In this study, our primary objective was to describe the epidemiology of neuropsychiatric comorbidities in Mexican patients with invasive prolactinomas. The secondary aim of the study was to describe how these comorbidities are modified by treatment with cabergoline, through follow-up with standardized clinical scales. Methods This was a retrospective analytic study. Data were pulled from clinical records and evaluations of patients at baseline and at six-month follow-ups.  Results A total of 10 patients were included in the study. None of them had any prior psychiatric diagnosis. At the initial evaluation, 70% were diagnosed with depression or anxiety. During follow-up, two patients developed neuropsychiatric symptoms; there was a significant reduction in tumor size but no difference was found in clinimetric scores for neuropsychiatric comorbidities. Conclusions Patients with giant prolactinomas may present with several neuropsychiatric symptoms throughout the course of their disease. Although there are several mechanisms involved, it is important to keep in mind that cabergoline may interfere with the dopaminergic pathways involved. This study was underpowered to determine the association but can serve as a pilot for further research on this topic.

Start low, go slowly - mental abnormalities in young prolactinoma patients under cabergoline therapy

Background Prolactin-secreting pituitary adenomas in childhood and adolescence are rare. First-line therapy consists of dopamine agonists (DAs) like cabergoline. Experience in treating prolactinomas in paediatric and adolescent patients is limited. Methods This study was a retrospective analysis of clinical data, laboratory data, radiological findings and medical treatment of paediatric and adolescent patients with prolactinomas between 2009 and 2018. Results Our cohort of nine patients had a median age at diagnosis of 13 years (range 5-17). Main presenting symptoms were weight gain, disorders of the pituitary-gonadal axis and headache. Treatment with cabergoline resulted in a marked reduction in prolactin concentration in all nine patients. Tumour mass reduction was confirmed by magnetic resonance imaging (MRI) scan in seven patients. Noteworthy is that cabergoline therapy triggered frequent adverse effects in a total of eight patients - seven of whom suffered from mental disorders, five of whom had neurological symptoms and five of whom had gastrointestinal problems. The adverse effects occurred at a median dose of only 0.5 mg/week (range 0.25-2.0). Most symptoms were alleviated after the cabergoline dose was lowered. Therapy discontinuation was not necessary in any patient. Conclusions Cabergoline effectively lowers prolactin levels and may reduce tumour mass in paediatric and adolescent patients with prolactinomas. Potential adverse effects may include mental disorders and behavioural problems even at low cabergoline doses. Low starting doses and careful individual dose adjustments are required to enable therapy adherence.

Controversial issues in the management of hyperprolactinemia and prolactinomas - An overview by the Neuroendocrinology Department of the Brazilian Society of Endocrinology and Metabolism

Prolactinomas are the most common pituitary adenomas (approximately 40% of cases), and they represent an important cause of hypogonadism and infertility in both sexes. The magnitude of prolactin (PRL) elevation can be useful in determining the etiology of hyperprolactinemia. Indeed, PRL levels > 250 ng/mL are highly suggestive of the presence of a prolactinoma. In contrast, most patients with stalk dysfunction, drug-induced hyperprolactinemia or systemic diseases present with PRL levels < 100 ng/mL. However, exceptions to these rules are not rare. On the other hand, among patients with macroprolactinomas (MACs), artificially low PRL levels may result from the so-called "hook effect". Patients harboring cystic MACs may also present with a mild PRL elevation. The screening for macroprolactin is mostly indicated for asymptomatic patients and those with apparent idiopathic hyperprolactinemia. Dopamine agonists (DAs) are the treatment of choice for prolactinomas, particularly cabergoline, which is more effective and better tolerated than bromocriptine. After 2 years of successful treatment, DA withdrawal should be considered in all cases of microprolactinomas and in selected cases of MACs. In this publication, the goal of the Neuroendocrinology Department of the Brazilian Society of Endocrinology and Metabolism (SBEM) is to provide a review of the diagnosis and treatment of hyperprolactinemia and prolactinomas, emphasizing controversial issues regarding these topics. This review is based on data published in the literature and the authors' experience.

Neuropsychiatric and metabolic aspects of dopaminergic therapy: perspectives from an endocrinologist and a psychiatrist

The dopaminergic treatment represents the primary treatment in prolactinomas, which are the most common pituitary adenomas and account for about 40% of all pituitary tumours with an annual incidence of six to ten cases per million population. The dopaminergic treatment includes ergot and non-ergot derivatives with high affinity for the dopamine receptors D1 or/and D2. Through the activation of the dopaminergic pathway on pituitary lactotrophs, the dopamine agonists inhibit the prolactin synthesis and secretion, therefore normalizing the prolactin levels and restoring eugonadism, but they also lead to tumour shrinkage. Treatment with dopamine agonists has been associated - apart from the common side effects such as gastrointestinal symptoms, dizziness and hypotension - with neuropsychiatric side effects such as impulse control disorders (e.g. pathological gambling, compulsive shopping, hypersexuality and binge eating) and also with behavioral changes from low mood, irritability and verbal aggressiveness up to psychotic and manic symptoms and paranoid delusions not only in patients with prolactinomas but also in patients with Parkinson's disease and restless leg syndrome. They usually have de novo onset after initiation of the dopaminergic treatment and have been mainly reported in patients with Parkinson's disease, who are being treated with higher doses of dopamine agonists. Moreover, dopamine and prolactin seem to play an essential role in the metabolic pathway. Patients with hyperprolactinemia tend to have increased body weight and an altered metabolic profile with hyperinsulinemia and increased prevalence of diabetes mellitus in comparison to healthy individuals and patients with non-functioning pituitary adenomas. Treatment with dopamine agonists in these patients in short-term studies seems to lead to weight loss and amelioration of the metabolic changes. Together these observations provide evidence that dopamine and prolactin have a crucial role both in the regard and metabolic system, findings that merit further investigation in long-term studies.