Antidepressant use and circulating prolactin levels

Exposure to psychotropic drugs and breast cancer risk in patients with bipolar disorder and major depressive disorder: a nested case-control study

Breast cancer is one of the most prevalent and serious types of cancer globally. Previous literature has shown that women with mental illness may have an increased risk of breast cancer, however whether this risk is associated with the use of psychotropic drugs has yet to be elucidated. This study aimed to assess such risk among women with major depressive disorder (MDD) and bipolar disorder (BD). A nested case-control study design was used with data obtained from the Taiwan National Health Insurance Research Database. Logistic regression analysis with adjustments for demographic characteristics, medical and mental comorbidities, and all-cause clinical visits was performed to estimate the risk of breast cancer according to the cumulative defined daily dose (cDDD) of psychotropic drugs. The study included 1564 women with MDD or BD who had breast cancer, and 15,540 women with MDD or BD who did not have breast cancer. After adjusting for important confounders, the long-term use of valproic acid (odds ratio, 95% confidence interval: 0.58, 0.39-0.56, cDDD ≥ 365), citalopram (0.58, 0.37-0.91, cDDD 180-365), and sertraline (0.77, 0.61-0.91, cDDD ≥ 365) was associated with a lower risk of breast cancer compared to a cDDD < 30. The short-term use of fluvoxamine (0.82, 0.69-0.96, cDDD 30-180), olanzapine (0.54, 0.33-0.89, cDDD 30-179), risperidone (0.7, 0.51-0.98, cDDD 30-179), and chlorpromazine (0.48, 0.25-0.90, cDDD 30-179) was associated with a lower risk of breast cancer. We found no evidence of an increased risk of breast cancer in patients with MDD or BD receiving psychotropic drugs.

The Involvement of Prolactin in Stress-Related Disorders

The most important and widely studied role of prolactin (PRL) is its modulation of stress responses during pregnancy and lactation. PRL acts as a neuropeptide to support physiological reproductive responses. The effects of PRL on the nervous system contribute to a wide range of changes in the female brain during pregnancy and the inhibition of the hypothalamic-pituitary axis. All these changes contribute to the behavioral and physiological adaptations of a young mother to enable reproductive success. PRL-driven brain adaptations are also crucial for regulating maternal emotionality and well-being. Hyperprolactinemia (elevated PRL levels) is a natural and beneficial phenomenon during pregnancy and lactation. However, in other situations, it is often associated with serious endocrine disorders, such as ovulation suppression, which results in a lack of offspring. This introductory example shows how complex this hormone is. In this review, we focus on the different roles of PRL in the body and emphasize the results obtained from animal models of neuropsychiatric disorders.

Treatments of psychiatric disorders, hyperprolactinemia and dopamine agonists

While the prevalence of hyperprolactinemia under antidepressants is very low, its prevalence under antipsychotics, particularly of the first generation, is high. Antipsychotics act by blocking dopamine activity at the level of the dopamine type 2 receptor (D2R). When prolactin levels exceed 80-100 ng/ml, a pituitary adenoma must be ruled out by MRI. Treatment of hyperprolactinemia is necessary only in cases with clinical symptoms of hypogonadism. Three treatment options are possible: switch to a less hyperprolactinemic antipsychotic, sex steroid supplementation or dopamine agonist (which normalizes prolactin levels in only half of cases). Fortunately, psychotic exacerbation due to the opposing effects of antipsychotics and dopamine agonists on the D2R seems very rare. When a patient presents with a macroprolactinoma, particularly with optic chiasm compression, surgery or dopamine agonists may be proposed. The agonists are effective in reducing tumor mass and improving visual defects in the majority of patients but rarely normalize prolactin levels.

Effect of sertraline on depression severity and prolactin levels in women with polycystic ovary syndrome: a placebo-controlled randomized trial

There is a paucity of data regarding the safety and efficacy of antidepressant therapy in women with polycystic ovary syndrome and depression. The effect of antidepressant medications on circulating prolactin levels is of concern in this patient population. We aimed to evaluate the effect of sertraline on depression severity and serum prolactin levels in women with polycystic ovary syndrome and mild-to-moderate depression. In a parallel-design, two-center, randomized controlled trial, we stratified participants according to their baseline prolactin level into normal (<25 ng/mL) and high (≥25 ng/mL) prolactin groups. Each group was randomized to receive 50 mg daily sertraline (up-titrated after 25 mg daily for 1 week) or placebo. The enrolling physicians, outcome assessors, and study subjects were all blind to the treatment. Depression severity was assessed by the Hamilton depression rating scale at baseline, the third, and the sixth weeks. The primary efficacy outcome was a change in depression severity. Prolactin levels were checked at baseline and after 6 weeks, and the safety outcome was the alteration in prolactin levels. Overall, 513 women were screened for eligibility in two outpatient clinics. Ultimately, 74 (38 normal prolactin and 36 high prolactin level) individuals were randomized. After 6 weeks of follow-up, depression severity was significantly reduced among patients who received sertraline regardless of the baseline prolactin levels (all between subjects P < 0.001). Furthermore, there was no difference in prolactin levels between the sertraline and placebo arms in normal (P = 0.80) or high prolactin (P = 0.21) groups. Sertraline is a well-tolerated and effective choice for treating depression in women with polycystic ovary syndrome. Future studies with longer follow-up periods are required to draw more robust conclusions.

Mechanisms of Central Hypogonadism

Reproductive function depends upon an operational hypothalamo–pituitary–gonadal (HPG) axis. Due to its role in determining survival versus reproductive strategies, the HPG axis is vulnerable to a diverse plethora of signals that ultimately manifest with Central Hypogonadism (CH) in all its many guises. Acquired CH can result from any pituitary or hypothalamic lesion, including its treatment (such as surgical resection and/or radiotherapy). The HPG axis is particularly sensitive to the suppressive effects of hyperprolactinaemia that can occur for many reasons, including prolactinomas, and as a side effect of certain drug therapies. Physiologically, prolactin (combined with the suppressive effects of autonomic neural signals from suckling) plays a key role in suppressing the gonadal axis and establishing temporary CH during lactation. Leptin is a further key endocrine regulator of the HPG axis. During starvation, hypoleptinaemia (from diminished fat stores) results in activation of hypothalamic agouti-related peptide neurons that have a dual purpose to enhance appetite (important for survival) and concomitantly suppresses GnRH neurons via effects on neural kisspeptin release. Obesity is associated with hyperleptinaemia and leptin resistance that may also suppress the HPG axis. The suppressibility of the HPG axis also leaves it vulnerable to the effects of external signals that include morphine, anabolic-androgenic steroids, physical trauma and stress, all of which are relatively common causes of CH. Finally, the HPG axis is susceptible to congenital malformations, with reports of mutations within >50 genes that manifest with congenital CH, including Kallmann Syndrome associated with hyposmia or anosmia (reduction or loss of the sense of smell due to the closely associated migration of GnRH with olfactory neurons during embryogenesis). Analogous to the HPG axis itself, patients with CH are often vulnerable, and their clinical management requires both sensitivity and empathy.

Glucose Metabolism, Thyroid Function, and Prolactin Level in Adolescent Patients With First Episode of Schizophrenia and Affective Disorders

Schizophrenia and affective spectrum disorders (ASD) typically begin in adolescence or early adulthood. The pathophysiological mechanisms underlying these disorders are still not fully understood, and recent studies have suggested an involvement of dysfunctions in cardiometabolic and neuroendocrine systems at the onset of both disorders. In this context, we aimed to assess thyroid function, prolactin level, glucose metabolism, and lipid profile in drug naive adolescents, comparing patients with first episode of schizophrenia spectrum disorders (SSD) and patients with ASD. We performed a retrospective chart review from inpatients aged from ten to eighteen years, referred to Child and Adolescent Psychiatric Unit of University of Bari "Aldo Moro" over a period of 4 years, with diagnosis of SSD (n=30) or ASD (n=22), according to Diagnostic and Statistical Manual for Mental Disorders-fifth edition (DSM-5) criteria. Data on serum prolactin, glucose, insulin, total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, triglycerides, thyroid stimulating hormone, free triiodothyronin, and free thyroxin were collected, and the insulin resistance (IR) indexes "HOMA1-IR" and "HOMA2-IR" were calculated. The multivariable linear regression models, adjusting for potential confounding factors (age, sex, and BMI), showed HOMA1-IR (p=0.001), HOMA2-IR (p=0.002), glucose (p=0.004), insulin (p=0.004) and free thyroxin (p<0.001) values higher in the SSD group than in ASD. No others significant differences were found. Our findings suggest the need for a metabolic and endocrine screening at the onset of SSD and ASD, particularly for indexes of IR, that is a testable and treatable risk factor for cardiometabolic diseases. Further studies are required to better understand the role of endocrinological and metabolic dysfunctions at the onset of severe mental illness also considering influencing factors as age, gender, and BMI.

Pitfalls in the Diagnostic Evaluation of Hyperprolactinemia

An appropriate diagnostic evaluation is essential for the most appropriate treatment to be performed. Currently, macroprolactinemia is the third most frequent cause of nonphysiological hyperprolactinemia after drugs and prolactinomas. Up to 40% of macroprolactinemic patients may present with hypogonadism symptoms, infertility, and/or galactorrhea. Thus, the screening for macroprolactin is indicated not only for asymptomatic subjects but also for those without an obvious cause for their prolactin (PRL) elevation. Before submitting patients to macroprolactin screening and pituitary magnetic resonance imaging, one should rule out pregnancy, drug-induced hyperprolactinemia, primary hypothyroidism, and renal failure. The magnitude of PRL elevation can be useful in determining the etiology of hyperprolactinemia. PRL values >250 ng/mL are highly suggestive of prolactinomas and virtually exclude nonfunctioning pituitary adenomas (NFPAs) and other sellar masses as the etiology of hyperprolactinemia. However, they can also be found in subjects with macroprolactinemia, drug-induced hyper-prolactinemia or chronic renal failure. By contrast, most patients with NFPAs, drug-induced hyperprolactinemia, macroprolactinemia, or systemic diseases present with PRL levels <100 ng/mL. However, exceptions to these rules are not rare. Indeed, up to 25% of patients harboring a microprolactinoma or a cystic macroprolactinoma may also have PRL <100 ng/mL. Falsely low PRL levels may result from the so-called "hook effect," which should be considered in all cases of large (≥3 cm) pituitary adenomas associated with normal or mildly elevated PRL levels (≤250 ng/mL). The hook effect may be unmasked by repeating PRL measurement after a 1:100 serum sample dilution.

Depression, Antidepressant Use, and Breast Cancer Risk in Pre- and Postmenopausal Women: A Prospective Cohort Study

Background: Depression and antidepressant use is highly prevalent among U.S. women and may be related to increased breast cancer risk. However, prior studies are not in agreement regarding an increase in risk.Methods: We conducted a prospective cohort study within the Nurses' Health Study (NHS) and NHSII among females age 25 and older. Over more than 10 years of follow-up in each cohort, 4,014 incident invasive breast cancers were diagnosed. We used Cox proportional hazards regressions with updating of exposures and covariates throughout follow-up to estimate HRs and 95% confidence intervals (CIs) for associations between clinical depression and antidepressant use with invasive breast cancer risk. Analyses were repeated separately for in situ disease, as well as stratified by estrogen receptor (ER) subtype and menopausal status at diagnosis.Results: No statistically significant associations were observed between clinical depression (HR for reporting ≥3 times vs. 0, 1.13; 95% CI, 0.85-1.49) or antidepressant use (HR for reporting ≥3 times vs. 0, 0.92; 95% CI, 0.80-1.05) and invasive breast cancer risk in multivariable analyses. Likewise, we observed no significant associations between clinical depression or antidepressant use and risk of in situ, ER⁺, ER^-, premenopausal, or postmenopausal breast cancer.Conclusions: In the largest prospective study to date, we find no evidence that either depression or antidepressant use increase risk of breast cancer.Impact: The results of this study are reassuring in that neither depression nor antidepressant use appear to be related to subsequent breast cancer risk. Cancer Epidemiol Biomarkers Prev; 27(3); 306-14. ©2017 AACR.