Vol 5, No 2 (2024)
- Year: 2024
- Published: 06.07.2024
- Articles: 6
- URL: https://consortium-psy.com/jour/issue/view/17
- DOI: https://doi.org/10.17816/CP.202452
RESEARCH
Genetic Associations of Anhedonia: Insights into Overlap of Mental and Somatic Disorders
Abstract
BACKGROUND: Anhedonia is characterized by a reduced ability to anticipate, experience, and/or learn about pleasure. This phenomenon has a transdiagnostic nature and is one of the key symptoms of mood disorders, schizophrenia, addictions, and somatic conditions.
AIM: To evaluate the genetic architecture of anhedonia and its overlap with other mental disorders and somatic conditions.
METHODS: We performed a genome-wide association study of anhedonia on a sample of 4,520 individuals from a Russian non-clinical population. Using the available summary statistics, we calculated polygenic risk scores (PRS) to investigate the genetic relationship between anhedonia and other psychiatric or somatic phenotypes.
RESULTS: No variants with a genome-wide significant association were identified. PRS for major depression, bipolar disorder, and schizophrenia were significantly associated with anhedonia. Conversely, no significant associations were found between PRS for anxiety and anhedonia, which aligns well with existing clinical evidence. None of the PRS for somatic phenotypes attained a significance level after correction for multiple comparisons. A nominal significance for the anhedonia association was determined for omega-3 fatty acids, type 2 diabetes mellitus, and Crohn’s disease.
CONCLUSION: Anhedonia has a complex polygenic architecture, and its presence in somatic diseases or normal conditions may be due to a genetic predisposition to mood disorders or schizophrenia.
5-15
Individual Burden of Illness Index in Bipolar Disorder Remission: A Cross-Sectional Study
Abstract
BACKGROUND: A population-based method for estimating disease burden is commonly used. Nevertheless, these measurements do not entirely capture the comprehensive burden of illness on an individual patient. To address the problem, the Individual Burden of Illness Index (IBI index) Index was created and validated, specifically for major depressive disorder. The IBI represents the overall influence of the condition, encompassing distress from symptom intensity, functional impairment, and the patient’s quality of life.
AIM: The aim of the study was to approve and validate the IBI index for the integral assessment of disease burden in patients with bipolar disorder (BD) in remission.
METHODS: The cross-sectional study was conducted in the outpatient psychiatric services in Saint Petersburg, Russia, from April through October 2020. Eighty-five patients aged 18 to 45 (mean age 36.6±5.7 years) with BD (type I — 75%, n=64; type II — 25%, n=21) in remission were examined. The study procedure included a structured clinical interview and the use of clinical scales: the World Health Organization’s Quality of Life Questionnaire, Hamilton Rating Scale for Depression (HDRS), Young Mania Rating Scale (YMRS), and Personal and the Social Performance Scale.
RESULTS: The principal component analysis in accordance with the adjusted one showed that the burden of illness in patients with BD in remission is directly related to the severity of residual depressive symptoms, reflected in the HDRS score: as the HDRS score increases (0.27, p <0.001), residual mania (-0.14, p <0.001), social functioning (-0.06, p <0.001), and quality of life (-0.04, p <0.001) decrease. In contrast, when there are remaining residual mania symptoms, as indicated by the YMRS score, the result tends to be a lower burden, better social functioning, and enhanced quality of life.
CONCLUSION: The study has demonstrated through statistical means a successful adaptation and validation of the previously calculated IBI index for patients with BD in remission. Residual affective symptoms were shown to have different impacts on the social functioning of patients with BD in remission, indicating the need for a timely assessment and targeted therapy of these symptoms in such patients.
17-30
Potential Neurophysiological Markers of Combat-Related Post-Traumatic Stress Disorder: A Cross-Sectional Diagnostic Study
Abstract
BACKGROUND: Studies suggest that the components of brain-evoked potentials (EPs) may serve as biomarkers of the post-traumatic stress disorder (PTSD) caused by participation in combat operations; however, to date, research remains fragmented, with no studies that have attempted to combine different paradigms. In addition, the mismatch negativity component has not been studied in a Russian sample of veterans with PTSD.
AIM: To identify objective neurophysiological markers of combat-related PTSD using the method of auditory-evoked potentials in active and passive listening paradigms.
METHODS: The study included a recording of auditory EPs in an oddball paradigm in three settings: 1) directed attention to auditory stimuli, 2) passive listening while viewing a neutral video sequence, and 3) viewing a video sequence associated with a traumatic event. Combatants diagnosed with PTSD (18 people) were compared with mentally healthy civilian volunteers (22 people).
RESULTS: An increase in the latency period of the early components of auditory EP (N100 and P200), an increase in the amplitude of the P200 component to a deviant stimulus, and a decrease to a standard one in the active listening
paradigm were established in the PTSD group. There were no significant differences in the parameters of the P300 component. The characteristics of mismatch negativity in the passive paradigm were revealed: an increase in the phenomenon amplitude, both when shown a video sequence associated with a traumatic event and when shown a neutral video sequence. A binary logistic regression model constructed using the selected parameters showed that the identified characteristics can potentially be considered as diagnostic markers of PTSD in combatants, as the classification accuracy stood at 87% (sensitivity — 81%, specificity — 91%).
CONCLUSION: Potential neurophysiological markers of PTSD are the following: the amplitude and latency of early components of auditory EPs in the paradigm of directed attention to stimuli and the amplitude of mismatch negativity during passive attention.
31-44
REVIEW
Inflammatory Hematological Ratios in Adolescents with Mental Disorders: A Scoping Review
Abstract
BACKGOUND: Inflammatory hematological ratios (IHRs), such as neutrophil to lymphocyte, monocyte to lymphocyte, and platelet to lymphocyte ratios, are associated with mental disorders, symptoms severity, and the disease phase. Evidence from the studies in adult patients has been summarized in systematic reviews and meta-analyses. The results of the studies in adolescents remain poorly systematized.
AIM: To summarize the findings from the studies that investigated the relationship of IHRs with mental disorders in adolescent patients.
METHODS: This scoping review included studies of IHRs in patients aged 10–19 years with mental disorders (other than anorexia nervosa), published in English by December 31, 2023. The search for relevant papers was performed in MEDLINE. The studies were categorized into two groups: studies with external controls (healthy adolescents) and studies with internal controls (patients in different phases of mental disorder, with or without self-harm/suicidal behaviors).
RESULTS: A total of 11 studies were included in the review (all cross-sectional ones). The results of these studies demonstrate that 1) adolescents with mental disorders (major depressive disorder, psychotic disorders, obsessive-compulsive disorder, attention deficit hyperactivity disorder, substance use disorders) have higher IHR values than individuals of the same age without corresponding disorders (5 studies); 2) IHR values are positively correlated with the severity of psychopathological symptoms (1 study); 3) higher IHR values are associated with the phase of the mental disorder — manic episode in bipolar disorder (1 study) and exacerbation of psychosis in psychotic disorders (1 study); and 4) higher IHR values are associated with self-harm/suicidal behaviors — suicide attempts (1 study) and non-suicidal self-injury (1 study).
CONCLUSION: IHRs are associated with mental disorders in adolescents, and higher IHR values are associated with a more severe/acute clinical presentation (severity of symptoms, mania, acute psychosis, self-harm/suicidal behaviors). Further studies of higher methodological quality are needed to evaluate the diagnostic and prognostic value of IHRs as biomarkers of mental disorders in adolescence.
45-61
Using the Strategy of Genome-Wide Association Studies to Identify Genetic Markers of Suicidal Behavior: A Narrative Review
Abstract
BACKGROUND: Several studies involving various suicidal phenotypes based on the strategy of the search of genome-wide associations with single nucleotide polymorphisms have been performed recently. These studies need to be generalized.
AIM: To systematize the findings of a number of genome-wide association studies (GWAS) for suicidal phenotypes, annotate the identified markers, analyze their functionality, and possibly substantiate the hypothesis holding that these phenotypes reflect a nonspecific set of gene variants that are relevant as relates to stress-vulnerability as a key endophenotype of suicidal behavior (SB).
METHODS: A search on the PubMed and related resources using the combinations “suicide AND GWAS” and “suicidal behavior AND GWAS” was performed. It yielded a total of 34 independent studies and meta-analyses.
RESULTS: For the 10 years since such studies emerged, they have undergone significant progress. Estimates of the SNP heritability of SB in some cases are comparable with estimates of heritability based on the twin method. Many studies show a high genetic correlation with the genomic markers of the most common mental disorders (depression, bipolar disorder, schizophrenia, post-traumatic stress disorder). At the same time, a genomic architecture specific to SB is also encountered. Studies utilizing the GWAS strategy have not revealed any associations of SB with candidate genes that had been previously studied in detail (different neurotransmitters, stress response system, polyamines, etc.). Frequently reported findings from various studies belong in three main groups: 1) genes involved in cell interactions, neurogenesis, the development of brain structures, inflammation, and the immune responses; 2) genes encoding receptors for neurotrophins and various components of the intracellular signaling systems involved in synaptic plasticity, embryonic development, and carcinogenesis; and 3) genes encoding various neuro-specific proteins and regulators.
CONCLUSION: In general, GWAS in the field of suicidology mainly serve the purpose of a deeper understanding of the pathophysiology of suicidal behavior. However, they also demonstrate growing capability in terms of predicting and preventing suicide, especially when calculating the polygenic risk score among certain populations (psychiatric patients) and in combination with tests of different modalities. From our point of view, there exists a set of markers revealed by the GWAS strategy that seems to point to a leading role played by stress vulnerability, an endophenotype that is formed during early development and which subsequently comes to play the role of key pathogenetic mechanism in SB.
63-77
CASE REPORT
Clinical Characteristics and Treatment Responses of Patients in Delirious Mania: A Case Series
Abstract
BACKGROUND: Delirious mania (DM) is a severe psychiatric condition having rapid onset of delirium, mania, and psychosis. It is an emergency condition as it has acute onset and is characterized by extreme hyperactivity. Catatonic signs may also be present. Very few cases have been reported from India, hence making it imperative to study its clinical characteristics and possible treatment, which can help in providing care to such patients in emergency settings.
CLINICAL CASES DESCRIPTION: This paper describes four cases with a diagnosis of DM — demography, clinical features, investigations, treatment. All the patients had an acute onset and rapid progression of symptoms, with clinical symptoms of talkativeness, increased psychomotor activity, decreased need for sleep, aggressive and violent behavior, increased libido, increased appetite with delusion of grandiosity, disorientation to time/place/person, impaired memory of recent events, impaired attention with fluctuating course, negativism, echolalia, and echopraxia.
CONCLUSION: There is a high likelihood of misdiagnosing DM in the absence of diagnostic guidelines. There should be an active search for the underlying aetiology in all cases of DM. Atypical antipsychotics and mood stabilizers may be used to treat less severe forms of DM. Modified electric convulsive treatment and intravenous benzodiazepines elicit a good response.
78-84