Mechanisms Involved in the Link between Depression, Antidepressant Treatment, and Associated Weight Change.

Major depressive disorder is a severe mood disorder associated with a marked decrease in quality of life and social functioning, accompanied by a risk of suicidal behavior. Therefore, seeking out and adhering to effective treatment is of great personal and society-wide importance. Weight changes associated with antidepressant therapy are often cited as the reason for treatment withdrawal and thus are an important topic of interest. There indeed exists a significant mechanistic overlap between depression, antidepressant treatment, and the regulation of appetite and body weight. The suggested pathomechanisms include the abnormal functioning of the homeostatic (mostly humoral) and hedonic (mostly dopaminergic) circuits of appetite regulation, as well as causing neuromorphological and neurophysiological changes underlying the development of depressive disorder. However, this issue is still extensively discussed. This review aims to summarize mechanisms linked to depression and antidepressant therapy in the context of weight change.

Peripheral Inflammatory Markers in Autism Spectrum Disorder and Attention Deficit/Hyperactivity Disorder at Adolescent Age.

Autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD) are associated with immune dysregulation. We aimed to estimate the pro- and anti-inflammatory activity/balance in ASD and ADHD patients at a little-studied adolescent age with respect to sex. We evaluated 20 ASD patients (5 girls, average age: 12.4 ± 1.9 y), 20 ADHD patients (5 girls, average age: 13.4 ± 1.8 y), and 20 age- and gender-matched controls (average age: 13.2 ± 1.9 y). The evaluated parameters included (1) white blood cells (WBCs), neutrophils, monocytes, lymphocytes, platelets, platelet distribution width (PDW), mean platelet volume, and derived ratios, as well as (2) cytokines-interferon-gamma, interleukin (IL)-1α, IL-1ß, IL-2, IL-4, IL-6, IL-8, and IL-10, tumor necrosis factor-alpha (TNF-α), and derived profiles and ratios. ASD adolescents showed higher levels of WBC, monocytes, IL-1α, IL-1ß, IL-2, IL-4, IL-6, IL-8, and IL-10, macrophages (M)1 profile, and anti-inflammatory profile than the controls, with ASD males showing higher monocytes, IL-6 and IL-10, anti-inflammatory profile, and a lower T-helper (Th)1/Th2+T-regulatory cell ratio than control males. The ADHD adolescents showed higher levels of PDW, IL-1ß and IL-6, TNF-α, M1 profile, proinflammatory profile, and pro-/anti-inflammatory ratio than the controls, with ADHD females showing a higher TNF-α and pro-/anti-inflammatory ratio than the control females and ADHD males showing higher levels of IL-1ß and IL-6, TNF-α, and M1 profile than the control males. Immune dysregulation appeared to be different for both neurodevelopmental disorders in adolescence.

Electrodermal activity spectral and nonlinear analysis - potential biomarkers for sympathetic dysregulation in autism.

Autism spectrum disorder (ASD) is a neurodevelopmental disease characterized by emotional and social deficits, which can be associated with sympathetic dysregulation. Thus, we aimed to analyze the electrodermal activity (EDA) using time, and novel spectral and nonlinear indices in ASD. The cohort consisted of 45 ASD boys and 45 age-matched controls. EDA was continuously recorded at rest. The EDA indices were evaluated by time-, spectral-, and nonlinear-domain analysis. Our results revealed increased non-specific skin conductance responses, spectral parameters in high and very-high frequency bands, approximate and symbolic information entropy indicating sympathetic overactivity in ASD vs. controls (p < 0.05, for all). Surprisingly, the nonlinear index from detrended fluctuation analysis α1 was lower in ASD vs. controls (p = 0.024) providing thus distinct information about qualitative features of complex sympathetic regulation. Concluding, the complex time, spectral, and nonlinear EDA indices revealed discrete abnormalities in sympathetic cholinergic regulation as one of the potential pathomechanisms contributing to cardiovascular complications in ASD.

Entropy Analysis of Neonatal Electrodermal Activity during the First Three Days after Birth.

The entropy-based parameters determined from the electrodermal activity (EDA) biosignal evaluate the complexity within the activity of the sympathetic cholinergic system. We focused on the evaluation of the complex sympathetic cholinergic regulation by assessing EDA using conventional indices (skin conductance level (SCL), non-specific skin conductance responses, spectral EDA indices), and entropy-based parameters (approximate, sample, fuzzy, permutation, Shannon, and symbolic information entropies) in newborns during the first three days of postnatal life. The studied group consisted of 50 healthy newborns (21 boys, average gestational age: 39.0 ± 0.2 weeks). EDA was recorded continuously from the feet at rest for three periods (the first day-2 h after birth, the second day-24 h after birth, and the third day-72 h after birth). Our results revealed higher SCL, spectral EDA index in a very-low frequency band, approximate, sample, fuzzy, and permutation entropy during the first compared to second and third days, while Shannon and symbolic information entropies were lower during the first day compared to other periods. In conclusion, EDA parameters seem to be sensitive in the detection of the sympathetic regulation changes in early postnatal life and which can represent an important step towards a non-invasive early diagnosis of the pathological states linked to autonomic dysmaturation in newborns.

Association of Sleep Architecture and Physiology with Depressive Disorder and Antidepressants Treatment.

Sleep problems are frequently associated with the principal diagnostic criteria for many mental disorders. Alterations in the sleep of depressive patients are of high clinical significance because continuous sleep problems raise the chance of relapse, recurrence, or suicide, as well as the need for augmenting medications. Most antidepressants have been proven to influence the sleep architecture. While some classes of antidepressants improve sleep, others may cause sleep impairment. The successful treatment of depressive disorder also requires an understanding of the effects of antidepressants on sleep. This article briefly reviews the physiology of sleep and the typical alterations in the sleep architecture in depressive patients and updates the different effects of the majority of antidepressants including novel drugs in clinical practice on sleep. The summary of the updated scientific findings of the relationship between depression and sleep disturbances could be clinically beneficial in choosing the best medication for depressive patients with concurrent sleep disorders.

Evaluation of hand hygiene: Is university medical education effective in prevention of hospital-acquired infections?

OBJECTIVE: Hand hygiene (HH) compliance is associated with effective prevention of health care-associated infections (HAI), the topic being very important due to current COVID-19 pandemic. There is a growing debate about the role of educational institutions in the low HH compliance of health workers. This study aimed to assess HH knowledge, self-assessment and attitudes of medical students in relation to provided educational background. METHODS: A cross-sectional survey (mixed methods-approach) combined with the curriculum analysis and questionnaires. Quantitative method: a questionnaire of knowledge of HH issues (QK), and a questionnaire of self-assessment and attitudes (SAQ) towards HH. Qualitative method focused on an analysis of content of the curriculum documents. RESULTS: 250 (KQ) and 238 (SAQ) questionnaires were analysed from students of general medicine (n = 262; average age 22.5 years). Below-average knowledge of HH and a high self-assessment of knowledge and compliance with HH was reported by 72.2% and 76.0% of students, respectively. Significant differences in knowledge and self-assessment of HH were found among study years and gender. The content analysis has revealed gaps in HH-related information in general medicine educational programme. CONCLUSIONS: It is highly expected that there might be some association between low HH knowledge level, false self-assessment and educational programme in medical students.

Role of Neuroendocrine, Immune, and Autonomic Nervous System in Anorexia Nervosa-Linked Cardiovascular Diseases.

Anorexia nervosa represents a severe mental disorder associated with food avoidance and malnutrition. In patients suffering from anorexia nervosa, cardiovascular complications are the main reason leading to morbidity and mortality. However, the origin and pathological mechanisms leading to higher cardiovascular risk in anorexia nervosa are still unclear. In this aspect, the issue of exact pathological mechanisms as well as sensitive biomarkers for detection of anorexia nervosa-linked cardiovascular risk are discussed. Therefore, this review synthesised recent evidence of dysfunction in multiple neuroendocrine axes and alterations in the immune system that may represent anorexia nervosa-linked pathological mechanisms contributing to complex cardiovascular dysregulation. Further, this review is focused on identification of non-invasive biomarkers for the assessment of increased cardiovascular risk in anorexia nervosa that can be linked to a clinical application. Complex non-invasive assessment of cardiovascular autonomic regulation-cardiac vagal control (heart rate variability), sympathetic vascular activity (blood pressure variability), and cardiovascular reflex control (baroreflex sensitivity)-could represent a promising tool for early diagnosis, personalized therapy, and monitoring of therapeutic interventions in anorexia nervosa particularly at a vulnerable adolescent age.

Novel Insight into Neuroimmune Regulatory Mechanisms and Biomarkers Linking Major Depression and Vascular Diseases: The Dilemma Continues.

Major depressive disorder (MDD) represents a serious health problem estimated to affect 350 million people globally. Importantly, MDD has repeatedly emerged as an etiological or prognostic factor in cardiovascular disease (CVD) development, including vascular pathology. Several linking pathomechanisms between MDD and CVD involve abnormal autonomic regulation, inflammation, and endothelial dysfunction as an early preclinical stage of atherosclerosis. However, the cause of accelerated atherosclerosis in MDD patients remains unclear. Recently, the causal relationships between MDD and mediator (e.g., inflammation and/or endothelial dysfunction), as well as the causal pathways from the mediator to atherosclerosis, were discussed. Specifically, MDD is accompanied by immune dysregulation, resulting in increased production of proinflammatory cytokines (e.g., interleukin (IL)-6 and tumor necrosis factor (TNF)-α), which could lead to depression-linked abnormalities in brain function. Further, MDD has an adverse effect on endothelial function; for example, circulating markers of endothelial dysfunction (e.g., soluble adhesion molecules, von Willebrand factor) have been linked with depression. Additionally, MDD-linked autonomic dysregulation, which is characterized by disrupted sympathovagal balance associated with excessive circulating catecholamines, can contribute to CVD. Taken together, activated inflammatory response, endothelial dysfunction, and autonomic dysregulation could affect gradual atherosclerosis progression, resulting in a higher risk of developing CVD in MDD. This review focused on the pathomechanisms linking MDD and CVD with respect to neuroimmune regulation, and the description of promising biomarkers, which is important for the early diagnosis and personalized prevention of CVD in major depression.

Reply to Comments: Using the Cardio-Ankle Vascular Index (CAVI) or the Mathematical Correction Form (CAVI0) in Clinical Practice.

We read with great interest Alizargar et al [...].

Novel Biomarkers of Early Atherosclerotic Changes for Personalised Prevention of Cardiovascular Disease in Cervical Cancer and Human Papillomavirus Infection.

Cervical cancer is associated with a causative role of human papillomavirus (HPV), which is a highly prevalent infection. Recently, women with a genital HPV infection were found to have increased incidence of cardiovascular diseases (CVD), including severe cardiovascular events such as myocardial infarction and stroke. The pathomechanisms of this relation are not yet fully understood, and may significantly affect the health of a large part of the population. Accelerated atherosclerosis is assumed to play a key role in the pathophysiology of this relationship. To identify high-risk groups of the population, it is necessary to stratify the CVD risk. Current algorithms, as widely used for the estimation of CVD risk, seem to be limited by the individual misclassification of high-risk subjects. However, personalised prediction of cardiovascular events is missing. Regarding HPV-related CVD, identification of novel sensitive biomarkers reflecting early atherosclerotic changes could be of major importance for such personalised cardiovascular risk prediction. Therefore, this review focuses on the pathomechanisms leading to HPV-related cardiovascular diseases with respect to atherosclerosis, and the description of potential novel biomarkers to detect the earliest atherosclerotic changes important for the prevention of CVD in HPV infection and cervical cancer.

Heart rate variability in healthy term newborns is related to delivery mode: a prospective observational study.

BACKGROUND: Early postnatal period is characterized by dramatic adaptation changes of cardiovascular and respiratory systems in newborns. There is still insufficient data regarding maturation of autonomic regulatory mechanisms in neonates early after delivery. Aim of this study was to analyze cardiac autonomic regulation in newborns within the first few postnatal days in relation to different modes of delivery using time and spectral heart rate variability analysis. METHODS: Eutrophic healthy term newborns (n = 46) were divided into three groups according to the delivery mode: vaginal delivery (VD group; n = 16), vaginal delivery with epidural analgesia (EDA group; n = 16), and caesarean section under general anesthesia (CS group; n = 14). Heart rate variability (HRV), blood pressure (BP), and blood oxygen saturation (SpO2) were measured within the first two hours after birth and on the third to fourth postnatal day. HRV parameters were evaluated in the time domain (RR intervals, mean square of successive differences - MSSD) and frequency domain (total spectral power - TP, absolute and relative low and high frequency powers). RESULTS: The HRV spectral analysis showed significantly higher relative power of the high-frequency band (HF%) in the VD group compared to the CS group early after delivery (p = 0.002). HRV parameters and BP significantly increased on the third to fourth postnatal day in all groups (p < 0.05). No significant differences in basic characteristics, BP and SpO2 were identified between groups during both measurements. CONCLUSIONS: HRV analysis revealed higher cardiovagal modulation in spontaneously born newborns without analgesia compared to neonates born by caesarean section. It could represent a potential pathomechanism that leads to discrete abnormal neurocardiac regulation associated with higher risk for worsened postnatal adaptation of cardiovascular system in surgically delivered neonates.

Endothelial function in children with white-coat hypertension.

Several studies have demonstrated endothelial dysfunction in patients with essential hypertension. However, the presence of endothelial dysfunction in children with white-coat hypertension has not been studied. We evaluated the endothelial function in children with white-coat hypertension and essential hypertension using a novel method based on the assessment of flow-mediated dilation (FMD). Study involved 106 children: 30 white-coat hypertensives (age 16.3 ± 1.3 years, mean ± SD), 30 essential hypertensives (age 16.4 ± 1.3 years), and 46 healthy controls (age 16.2 ± 1.4 years). Ultrasound scans of the right brachial artery were performed using Prosound F75 Aloka system during protocol: baseline (1 min), forearm ischemia (5 min), and post-occlusion phase (3 min). FMD (%) was expressed as a change of the arterial diameter from baseline to maximum post-occlusion value and the values < 5% were considered as deficient FMD. We found significantly lower FMD in both essential and white-coat hypertension compared to control group (p < 0.05 for both) with no significant difference between the hypertensive groups. Deficient FMD was found in both hypertensive groups, but not in the control group. The occurence of deficient FMD was significantly higher in both essential and white-coat hypertensives compared to controls (p < 0.01 for both) with no significant difference between the hypertensive groups. Our findings of endothelial dysfunction indicated by impaired FMD in pediatric patients with white-coat hypertension could help to elucidate the mechanisms of the increased cardiovascular risk that could be similar as found in essential hypertension; therefore, white-coat hypertension should not be considered a benign phenomenon.

Heart rate variability affected by radiofrequency electromagnetic field in adolescent students.

This study examines the possible effect of radiofrequency (RF) electromagnetic fields (EMF) on the autonomic nervous system (ANS). The effect of RF EMF on ANS activity was studied by measuring heart rate variability (HRV) during ortho-clinostatic test (i.e., transition from lying to standing and back) in 46 healthy grammar school students. A 1788 MHz pulsed wave with intensity of 54 ± 1.6 V/m was applied intermittently for 18 min in each trial. Maximum specific absorption rate (SAR10 ) value was determined to 0.405 W/kg. We also measured the respiration rate and estimated a subjective perception of EMF exposure. RF exposure decreased heart rate of subjects in a lying position, while no such change was seen in standing students. After exposure while lying, a rise in high frequency band of HRV and root Mean Square of the Successive Differences was observed, which indicated an increase in parasympathetic nerve activity. Tympanic temperature and skin temperature were measured showing no heating under RF exposure. No RF effect on respiration rate was observed. None of the tested subjects were able to distinguish real exposure from sham exposure when queried at the end of the trial. In conclusion, short-term RF EMF exposure of students in a lying position during the ortho-clinostatic test affected ANS with significant increase in parasympathetic nerve activity compared to sham exposed group. Bioelectromagnetics. 39:277-288, 2018. © 2018 Wiley Periodicals, Inc.

Improved assessment of arterial stiffness using corrected cardio-ankle vascular index (CAVI0) in overweight adolescents with white-coat and essential hypertension.

Arterial stiffness is a marker of vascular damage. Although adiposity increases cardiovascular risk, the relationship between paediatric overweight and arterial stiffness is unclear. The study aimed to evaluate the simultaneous effect of hypertension and overweight on arterial stiffness using cardio-ankle vascular index (CAVI) and related novel, theoretically blood pressure (BP)-independent, index CAVI0. CAVI and CAVI0 were measured in 140 adolescent boys (16.0 ± 1.9 years) divided into age-matched groups: normal-weight normotensives, overweight normotensives, overweight white-coat hypertensives, and overweight essential hypertensives. Overweight normotensives had significantly lower CAVI and CAVI0 compared to normal-weight normotensives (4.81 ± 0.64 vs. 5.33 ± 0.66, p < .01; 7.10 ± 0.99 vs. 7.81 ± 1.00, p < .01, respectively). CAVI and CAVI0 in overweight essential hypertensives showed no significant difference compared to normal-weight normotensives and were significantly higher compared to overweight normotensives (5.32 ± 0.77 vs. 4.81 ± 0.64, p < .01; 7.77 ± 1.19 vs. 7.10 ± 0.99, p < .01, respectively). CAVI, but not CAVI0, was associated positively with diastolic pressure (0.022 mmHg-1, p = .002) and negatively with pulse pressure (-0.022 mmHg-1, p = .001), and it was significantly higher in overweight white-coat hypertensives compared to overweight normotensives (5.20 ± 0.63 vs. 4.81 ± 0.64, p < .05). The lowering effect of overweight on arterial stiffness indexed by CAVI and CAVI0 in hypertensive adolescents seems to counterbalance the early arteriosclerotic effect of essential hypertension. The increase in CAVI, but not CAVI0, in overweight white-coat hypertensives could be attributable to residual BP dependence of CAVI, which is not present in CAVI0. Under certain conditions, CAVI0 may offer a clinically relevant improved assessment of arterial stiffness superior to CAVI.

Neonatal Marfan syndrome: Report of two cases.

Marfan syndrome is rarely diagnosed in the neonatal period because of variable expression and age-dependent appearance of clinical signs. The prognosis is usually poor due to high probability of congestive heart failure, mitral and tricuspid regurgitations with suboptimal response to medical therapy and difficulties in surgical management. The authors have studied two cases of Marfan syndrome in the newborn period. Two cases of neonatal Marfan syndrome, one male and one female, were diagnosed by characteristic physical appearance. Both infants had significant cardiovascular abnormalities diagnosed by ultrasonography. Genetic DNA analysis in the second case confirmed the mutations in the fibrillin-1 gene located on chromosome 15q21 which is responsible for the development of Marfan syndrome. The boy died at six weeks of age with signs of rapidly progressive left ventricular failure associated with pneumonia. The second infant was having only mild signs of congestive heart failure and has been treated with beta blockers. At the age of 4 years her symptoms of congestive heart failure had worsened due to progression of mitral and tricuspid insufficiency and development of significant cardiomegaly. Mitral and tricuspid valvuloplasy had to be done at that time. Early diagnosis of Marfan syndrome in the newborn period can allow treatment in the early stages of cardiovascular abnormalities and may improve the prognosis. It also helps to explain to the family the serious health problem of their child.

Arterial stiffness evaluated by cardio-ankle vascular index (CAVI) in adolescent hypertension.

Elevated blood pressure (BP) is a major risk factor for atherosclerosis. As the studies concerning vascular alterations in pediatric patients are rare, we aimed to study the relationship between hypertension and arterial stiffness in adolescence by novel method independent from BP during examination. Twenty nonobese adolescent boys (16.5 ± 0.4 years) with newly diagnosed essential hypertension, 20 adolescent boys (16.7 ± 0.4 years) with newly diagnosed white-coat hypertension, and 20 healthy controls matched to age and body mass index were examined. Cardio-ankle vascular index (CAVI), brachial-ankle pulse wave velocity (baPWV), pre-ejection period (PEP), and ejection time (ET) were evaluated. CAVI was significantly increased in essential hypertension patients compared with controls (p < 0.05) with no significant difference in white-coat hypertension patients. Significantly higher baPWV was found in essential and white-coat hypertension patients compared with controls (both p < 0.001). White-coat hypertension patients showed significantly shortened PEP and ET compared with controls (p < 0.01 and p < 0.001, respectively) and essential hypertension patients (both p < 0.05). For the first time, the arterial stiffness in adolescents with newly diagnosed essential and white-coat hypertension was studied using BP-independent index CAVI combined with conventional baPWV. Our study revealed significantly increased CAVI in adolescents with newly diagnosed essential hypertension compared with controls. Our findings could help to understand hypertension-atherosclerosis interaction.

Symbolic dynamics of heart rate variability - a promising tool to investigate cardiac sympathovagal control in attention deficit/hyperactivity disorder (ADHD)?

We aimed to evaluate complex cardiac sympathovagal control in attention deficit/hyperactivity disorder (ADHD) by using heart rate variability (HRV) nonlinear analysis - symbolic dynamics. We examined 29 boys with untreated ADHD and 25 healthy boys (age 8-13 years). ADHD symptoms were evaluated by ADHD-RS-IV scale. ECG was recorded in 3 positions: baseline supine position, orthostasis, and clinostasis. Symbolic dynamics indices were used for the assessment of complex cardiac sympathovagal regulation: normalised complexity index (NCI), normalised unpredictability index (NUPI), and pattern classification measures (0V%, 1V%, 2LV%, 2UV%). The results showed that HRV complexity was significantly reduced at rest (NUPI) and during standing position (NCI, NUPI) in ADHD group compared to controls. Cardiac-linked sympathetic index 0V% was significantly higher during all posture positions and cardiovagal index 2LV% was significantly lower to standing in boys suffering from ADHD. Importantly, ADHD symptom inattention positively correlated with 0V%, and negatively correlated with NCI, NUPI. Concluding, symbolic dynamics revealed impaired complex neurocardiac control characterised by potential cardiac beta-adrenergic overactivity and vagal deficiency at rest and to posture changes in boys suffering from ADHD that is correlated with inattention. We suggest that symbolic dynamics indices could represent promising cardiac biomarkers in ADHD.

Respiratory sinus arrhythmia as a non-invasive index of 'brain-heart' interaction in stress.

Respiratory sinus arrhythmia (RSA) is accepted as a peripheral marker of cardiac-linked parasympathetic regulation. According to polyvagal theory, the RSA is also considered as the index of emotion regulation. The neurovisceral integration model posits that parasympathetic modulation of the heart marked by RSA is related to complex nervous regulation associated with emotional and cognitive processing. From this perspective, high resting RSA amplitude associated with a greater withdrawal during stressors and subsequent recovery could represent a flexible and adaptive physiological response system to a challenge. Conversely, low resting RSA accompanied by an inadequate reactivity to stress might reflect maladaptive regulatory mechanisms. The RSA reactivity is different with various types of stressors: while the RSA decreases to cognitive tasks indicating a vagal withdrawal, the RSA magnitude increases to emotional challenge indicating an effective cognitive processing of emotional stimuli. The RSA reactivity to stress could have important implications for several mental disorders, e.g. depressive or anxiety disorder. It seems that the study of the RSA, as a non-invasive index of 'brain-heart' communication, could provide important information on the pathway linked to mental and physical health.

Myocardial scarring after repair of anomalous origin of the left coronary artery from pulmonary artery.

OBJECTIVES: Prognosis of patients with anomalous origin of the left coronary artery from pulmonary artery has dramatically improved as a result of both, early diagnosis and improvements in surgical techniques. Post surgical complications are rare and most patients show quick improvement of the left ventricular performance after repair with complete functional recovery within one year after surgery. Exercise-induced electrocardiographic changes have been found in patients postoperatively and scars and perfusion deficits of the left ventricle may not be detected by standard echocardiographic evaluation. METHODS: Authors present 6 cases of anomalous origin of the left coronary artery from pulmonary artery observed at Martin Univesity Hospital and Pediatric Cardiology Clinic over the last eight-year period. In order to assess the presence of myocardial injury, cardiovascular magnetic resonance imaging with late gadolinium enhancement technique was performed in all 6 cases one year after surgical correction. RESULTS: One patient died 1.5 year after surgical treatment. One year after surgery, the heart size and myocardial functions returned to normal in all patients. Cardiovascular magnetic resonance imaging demonstrated subendocardial late gadolinium enhancement in varios segments of the left ventricle, representing myocardial fibrosis in all patients one year after surgical correction. CONCLUSION: Because of the presence of scarr tissue, the long term prognosis of these patients remains unclear. The damaged tissue may have arrhythmogenic potential, therefore close follow-up, excercise testing and avoidance of high-level sport activities may be needed.

Effect of Acute Ketamine Treatment on Sympathetic Regulation Indexed by Electrodermal Activity in Adolescent Major Depression.

Ketamine is a potential rapid-onset antidepressant characterized by sympathomimetic effects. However, the question of ketamine's use in treating adolescents' major depressive disorder (MDD) is still discussed. Thus, we aimed to study the acute effect of ketamine infusion treatment on sympathetic regulation using electrodermal activity (EDA) in addition to an assessment of depressive symptomatology in MDD adolescents. Twenty hospitalized adolescent girls with MDD (average age: 15.0 ± 1.46 yrs.) were examined before and two hours after a single intravenous infusion of ketamine. EDA was continuously recorded for 6 min, and depressive symptoms were assessed before and two hours after ketamine administration. The evaluated parameters included skin conductance level (SCL), nonspecific electrodermal responses (NS-SCRs), MADRS (questions no. 1-10, total score), and CDI (items A-E, total score). EDA parameters showed no significant changes after the ketamine treatment, and depressive symptoms were significantly reduced after the ketamine infusion. The analysis revealed a significant negative correlation between index SCL and CDI-A, CDI-E, and the total CDI score and between index NS-SCRs and MADRS no. 4 before the ketamine treatment. In conclusion, ketamine improved depressive symptomatology without a significant effect on EDA, indicating its potential safety and efficiency as an acute antidepressant intervention in adolescent MDD.