Thyrotropin and prolactin responses to ECT in schizophrenia and depression

Electroconvulsive Therapy in Psychiatric Disorders: A Narrative Review Exploring Neuroendocrine-Immune Therapeutic Mechanisms and Clinical Implications

Electroconvulsive therapy (ECT) is based on conducting an electrical current through the brain to stimulate it and trigger generalized convulsion activity with therapeutic ends. Due to the efficient use of ECT during the last years, interest in the molecular bases involved in its mechanism of action has increased. Therefore, different hypotheses have emerged. In this context, the goal of this review is to describe the neurobiological, endocrine, and immune mechanisms involved in ECT and to detail its clinical efficacy in different psychiatric pathologies. This is a narrative review in which an extensive literature search was performed on the Scopus, Embase, PubMed, ISI Web of Science, and Google Scholar databases from inception to February 2022. The terms "electroconvulsive therapy", "neurobiological effects of electroconvulsive therapy", "molecular mechanisms in electroconvulsive therapy", and "psychiatric disorders" were among the keywords used in the search. The mechanisms of action of ECT include neurobiological function modifications and endocrine and immune changes that take place after ECT. Among these, the decrease in neural network hyperconnectivity, neuroinflammation reduction, neurogenesis promotion, modulation of different monoaminergic systems, and hypothalamus-hypophysis-adrenal and hypothalamus-hypophysis-thyroid axes normalization have been described. The majority of these elements are physiopathological components and therapeutic targets in different mental illnesses. Likewise, the use of ECT has recently expanded, with evidence of its use for other pathologies, such as Parkinson's disease psychosis, malignant neuroleptic syndrome, post-traumatic stress disorder, and obsessive-compulsive disorder. In conclusion, there is sufficient evidence to support the efficacy of ECT in the treatment of different psychiatric disorders, potentially through immune, endocrine, and neurobiological systems.

Systematic review of sex differences in the relationship between hormones and depression in HIV

BACKGROUND

Major depressive disorder is the most common neuropsychiatric comorbidity of human immunodeficiency virus (HIV), and women are more frequently affected in the general population and among those with HIV. The rate of depression in HIV is three times higher than the general population. Differences in biomarkers in neuroendocrine and inflammatory pathways are one possible explanation for the increased prevalence of depression in individuals with HIV, especially biological women. Therefore, we aimed to perform a systematic review identifying differences in neuroendocrine factors leading to depression in men versus women with HIV.

METHODS

A comprehensive search of 8 databases was performed, followed by title and abstract screening and later full-text screening by two independent researchers. A risk of bias assessment was completed.

RESULTS

Twenty-six full-text articles were included in the review. Significant correlations between depression and neuroendocrine marker levels were found for cortisol (both sexes), testosterone (only in men), oxytocin (only tested in women), and estradiol (only in women). No significant correlation between depression and hormone level was found for prolactin, dehydroepiandrosterone (DHEAS), or sex hormone binding globulin (SHBG). Nearly all studies included only men or women and did not directly compare neuroendocrine markers between the two sexes. One study found that the correlation between cortisol levels and depression scores was stronger in women than men.

CONCLUSION

Neuroendocrine systems are highly active in the brain and important in the development and persistence of mental illness. Given that HIV can, directly and indirectly, impact hormone signaling, it is likely contributing to the high rate of depression in individuals with HIV. However, few studies explore neuroactive hormones in depression and HIV, nor how this connection may differ between the sexes. More high-quality research is needed in this area to explore the link further and inform possible avenues of treatment.

Prolactin changes during electroconvulsive therapy: A systematic review and meta-analysis

BACKGROUND

Early studies reported a prolactin surge during electroconvulsive therapy (ECT). The aim of this study is to review and meta-analyze data on ECT-related prolactin changes.

METHOD

A systematic review and meta-analysis was conducted for trials investigating prolactin changes in ECT-treated patients using standard mean differences (SMD, 95% confidence intervals). Subgroup analyses included comparisons of ECT-related prolactin changes in women vs. men, patients receiving different anesthetics, bilateral vs. unilateral and high-vs. low-dose ECT.

RESULTS

In six trials including 109 ECT-treated patients and 74 controls, prolactin changes were larger in ECT-treated patients than in controls (SMD = 0.89, 95%CI = 0.55, 1.23, p < 0.001 and 1.03, 95%CI = 0.31, 1.75, p = 0.005 for the fixed and random-effect model respectively), despite heterogeneity in the samples (I² = 72%, τ² = 0.62). Effects were led by differences in patients premedicated with methohexital (SMD = 1.14, 95%CI = 0.7, 1.57, p < 0.001 for both fixed and random-effect model). A meta-regression reported significant age effects (coefficient estimate 2.32, 95%CI = -0.73, 3.91, p < 0.01). Additionally, prolactin changes were larger in ECT-treated women than men (SMD = 0.88, 95%CI = 0.58, 1.18, p < 0.001 and 0.99, 95%CI = 0.22, 1.75, p = 0.012 for the fixed and random effect model). Bilateral ECT-treated patients had larger increase than unilateral ECT-treated patients (SMD = -0.81, 95%CI = -1.35, -0.27, p = 0.003 and -0.86, 95%CI = -1.46, -0.25, p = 0.006 for the fixed and random-effect model). Comparisons between high- and low-dose ECT-treated patients could not be conducted. The quality of the studies was overall poor, with four exceptions.

DISCUSSION

Patients receiving ECT had larger prolactin increases than controls. Increases were larger in methohexital-premedicated patients, women vs. men and patients with bilateral vs. unilateral ECT.

Effects of electroconvulsive therapy on the thyrotropin-releasing hormone test in patients with depression

We investigated the acute and lasting effects of electroconvulsive therapy (ECT) on the thyroid-stimulating hormone (TSH) response to thyrotropin-releasing hormone (TRH) in patients with depression. The TRH stimulation test was conducted (1) under basal conditions, after a first ECT, and at the end of a therapeutic course of 7 ECTs in 20 inpatients with depression; (2) before the initiation of antidepressant therapy and after the therapeutic response in 16 other inpatients with depression who responded to antidepressant drug treatment; and (3) in 20 healthy control subjects. Baseline TSH levels were lower in patients with depression, especially in those with more severe depression who were considered appropriate for ECT. Before the treatment, TSH response to TRH did not differ between the patients with depression and controls; however, more blunted TSH responses to TRH were observed in these patients compared with the controls. TSH response to TRH changed neither with one ECT nor throughout consecutive ECT sessions in patients with depression. Drug treatment also was found to have no impact on this response. These findings suggest that the therapeutic action of ECT in depression is not directly related to its effects on the hypothalamic-pituitary-thyroid axis. However, possible delayed effects of ECT on the HPT axis function should not be overlooked.

Effects of electroconvulsive therapy on hypothalamic-pituitary-thyroid axis activity in depressed patients

In this study, the authors aimed to test the hypothesis that electroconvulsive therapy (ECT) may cause some alterations in hypothalamic-pituitary-thyroid (HPT) axis hormones and these responses may change throughout respective ECT sessions. Nineteen depressed inpatients (8 males, 11 females; mean age+/-S.D.: 44.77+/-10.59 years) considered suitable for ECT were included in the study. Each patient was exposed to 7 ECT sessions with general anaesthesia. The blood samples for measurements of thyroid-stimulating hormone (TSH), free thyroiodothyronine (fT3) and free thyroxine (fT4) were drawn before (baseline) and after propofol, immediately after ECT, and 30 and 60 min after ECT during the first and last (seventh) ECTs. In both the first and seventh ECTs, there was a significant increase in TSH levels 30 min after ECT compared to the pre-ECT values. Additionally, a significant decrease in post-ECT fT4 values compared to the baseline values was found only during the seventh ECT. No difference was detected in the TSH, fT3 and fT4 responses to ECT between males and females, and between bipolar and unipolar depressive patients. These results show that ECT may have some effects on the HPT system. However, whether there is a relationship between these neuroendocrine responses and the therapeutic effect of ECT is not clear.

Physiological effects of electroconvulsive therapy and transcranial magnetic stimulation in major depression

Major depressive episodes are associated with dysregulation of various physiologic systems. Antidepressant medications alter regulation of the hormonal and sleep systems. A thorough understanding of these changes may elucidate the pathophysiologic basis of the disorder [Amsterdam et al., 1989: Psychoneuroendocrinology 14:43-62], and interventions targeted directly at these systems are being increasingly recognized as possible treatments for depression [Wong et al., 2000: Proc Natl Acad Sci USA 97:325-330; Szuba et al., 1996: Proc Am Coll Neuropsychopharmacol Ann Meet]. These physiologic systems are regulated by the major neurotransmitters implicated in the etiology of mood disorders--norepinephrine, serotonin, and dopamine. Many of the hormones of import for this article also act as neurotransmitters and thus alter cerebral activity themselves [Owens and Nemeroff, 1993: Ciba Found Symp 172:296-308; Weitzner, 1998: Psychother Psychosom 67:125-132]. Parenteral infusion of hydrocortisone [DeBattista, 2000: Am J Psychiatry 157:1334-1337] and thyrotropin-releasing hormone (TRH) [Prange et al., 1972: Lancet 2:999-1002; Marangell et al., 1997: Arch Gen Psychiatry 54:214-222; Szuba, 1996: Proc Am Coll Neuropsychopharmacol Ann Meet.] produce acute antidepressant effects. Antagonists to corticotropin-releasing hormone and repeated parenteral infusion of TRH may have antidepressant activity when given during several weeks [Wong, 2000: Proc Natl Acad Sci USA 97:325-330; Arborelius et al., 1999: J Endocrinol 160:1-12; Callahan et al., 1997: Biol Psychiatry 41:264-272]. Manipulations of the sleep system through sleep deprivation can ameliorate depression [Szuba et al., 1994: Psychiatry Res 51:283-295; see Wirz-Justice et al., 1999: Biol Psychiatry 46:445-453 for review]. Sleep deprivation has been shown in more than three dozen studies published in the last three decades to produce marked, acute antidepressant effects in the majority of depressed individuals [Wirz-Justice, et al., 1999: Biol Psychiatry 46:445-453]. Thus, examination of the effects the two nonpharmacologic treatments, electroconvulsive therapy (ECT) and transcranial magnetic stimulation (TMS), produce in these physiologic systems may help elucidate their mechanisms of action, while enhancing understanding of the neurobiology of depressive illness. We will review these physiologic changes associated with depression, the effects that manipulations of these systems can have on depressive disorders, and then describe the effects the two techniques that can stimulate the human brain in vivo, ECT and TMS, exert on these systems.

Effects of thyrotropin-releasing hormone administration on the electroconvulsive therapy induced prolactin responses and seizure time

The effects of thyrotropin-releasing hormone (TRH) administration on electroconvulsive therapy (ECT)-induced prolactin (PRL) secretion and the duration of the seizure were studied in 14 depressed women. In a balanced order crossover design the patients were given 0.4 mg TRH or placebo intravenously 20 min before ECT during the first two sessions. In the third ECT session TRH was given just prior to ECT. ECT elicited the expected PRL response when given alone and when given 20 min after TRH when PRL plasma levels were high. During the coadministration design (third ECT session) PRL levels were raised not as a sum of the two stimuli but even significantly more. TRH failed to modify the duration of the seizure induced by ECT. Therefore, if TRH is involved in seizure modulation during ECT, our findings suggest a postictal rather than ictal role for TRH.

Electroconvulsive shock does not modify striatal contents of dopamine in MPTP-treated mice

It has been suggested that the therapeutic response to electroconvulsive therapy in depressed patients could be mediated by functional changes in the dopaminergic pathways; a favorable response to electroconvulsive therapy was also observed recently in patients with Parkinson's disease. To study a possible interference of electroconvulsive shock in the course of MPTP-induced parkinsonism in rodents, we measured the striatal content of dopamine in MPTP-treated mice that received electroconvulsive shock at various intervals in the course of MPTP neurotoxicity. Our results showed no immediate or delayed differences in striatal dopamine content of animals that received MPTP and electroconvulsive shock when compared with animals that received only MPTP, thus suggesting that the strong biological effects of MPTP and electroconvulsive shock on the brain may follow different biochemical mechanisms.