Genetic investigations of 100 inherited cardiac disease-related genes in deceased individuals with schizophrenia

Post-mortem genetic analysis of sudden unexplained death in a young cohort: a whole-exome sequencing study

Sudden unexplained death (SUD) constitutes a considerable portion of unexpected sudden death in the young. Molecular autopsy has proved to be an efficient diagnostic tool in the multidisciplinary management of SUD. Yet, many cases remain undiagnosed using the widely adopted targeted genetic screening strategies. Here, we investigated the genetic substrates of a young SUD cohort (18-40 years old) from China using whole-exome sequencing (WES), with the primary aim to identify novel SUD susceptibility genes. Within 255 previously acknowledged SUD-associated genes, 21 variants with likely functional effects (pathogenic/likely pathogenic) were identified in 51.9% of the SUD cases. More importantly, a set of 33 candidate genes associated with myopathy were identified to be novel susceptibility genes for SUD. Comparative analysis of the cumulative PHRED-scaled CADD score and polygenetic burden score showed that the amount and deleteriousness of variants in the 255 SUD-associated genes and the 33 candidate genes identified by this study were significantly higher compared with 289 randomly selected genes. A significantly higher genetic burden of rare variants (MAF < 0.1%) in the 33 candidate genes also highlighted putative roles of these genes in SUD. After incorporating these novel genes, the genetic testing yields of the current SUD cohort elevated from 51.9 to 66.7%. Our study expands understanding of the genetic variants underlying SUD and presents insights that improve the utility of genetic screenings.

Sudden Cardiac Death in People With Schizophrenia: Higher Risk, Poorer Resuscitation Profiles, and Differing Pathologies

BACKGROUND

People with schizophrenia account for approximately 1.0% of the population and seem to experience increased rates of sudden cardiac death (SCD).

OBJECTIVES

This study sought to determine characteristics of increased SCD in people with schizophrenia.

METHODS

The End Unexplained Cardiac Death (EndUCD) prospective state-wide registry compared people aged 15 to 50 years with and without schizophrenia who experienced SCD within a 2-year time period and were referred for forensic evaluation.

RESULTS

We identified 579 individuals, of whom 65 (11.2%) had schizophrenia. Patients with schizophrenia were more commonly smokers (46.2% vs 23.0%; P < 0.0001), consumed excess alcohol (32.3% vs 21.4%; P = 0.05), and used QTc-prolonging medications (69.2% vs 17.9%; P < 0.0001). They were less likely to arrest while exercising (0.0% vs 6.4%; P = 0.04). Unfavorable arrest-related factors included lower rates of witnessed arrest (6.2% vs 23.5%; P < 0.0001), more likely to be found in asystole (92.3% vs 73.3%; P < 0.0001), and being more likely to be found as part of a welfare check after a prolonged period of time (median 42 hours vs 12 hours; P = 0.003). There was more frequent evidence of decomposition, and they more commonly underwent autopsy (41.2% vs 26.4%; P = 0.04 and 93.8% vs 82.5%; P = 0.05), with a diagnosis of nonischemic cardiomyopathy being more common (29.2% vs 18.1%; P = 0.04).

CONCLUSIONS

People with schizophrenia account for 11% of young SCD patients referred for forensic investigations, exceeding population rates by 11-fold. They have a higher preexisting cardiac risk factor burden, unfavorable resuscitation profiles, and higher rates of nonischemic cardiomyopathy. Strategies targeting biopsychosocial support may deliver not only psychological benefits, but also help to decrease unwitnessed cardiac arrest.

Sudden Cardiac Death in Schizophrenia During Hospitalization: An Autopsy-Based Study

Schizophrenia is a severe mental disorder that is often comorbid with heart dysfunction and even sudden cardiac death (SCD). Clinical studies of SCD in schizophrenia have been largely reported, while there are limited autopsy studies that directly showed whole-scale information of such events. In this study, we present nine autopsy-based SCD cases in schizophrenia patients who died suddenly during hospitalization. Their medical records before and during hospitalization, and postmortem autopsy findings were summarized. These decedents had an average duration of schizophrenia for 6.83 ± 3.75 years with a male/female ratio of 4:5. They were all on intermittent antipsychotics medication before hospitalization and died within 15 days after hospitalization. Seven of the nine cases (77.8%) died of organic heart diseases such as severe coronary artery atherosclerosis (n = 4), myocarditis (n = 1), cardiomyopathy (n = 1), and pulmonary thromboembolism (n = 1). Two cases remained unexplained after systemic autopsy and toxicological examinations. Postmortem autopsy identified hepatic steatosis (n = 6) and respiratory inflammation (n = 3) as the most common associate extra-cardiac lesions. Our data provided autopsy-based data of SCD cases in schizophrenia and highlighted an intensive care of such patients during hospitalization.

Mapping the Knowledge of Antipsychotics-Induced Sudden Cardiac Death: A Scientometric Analysis in CiteSpace and VOSviewer

The drugs on the market for schizophrenia are first-generation and second-generation antipsychotics. Some of the first-generation drugs have more side effects than the other drugs, so they are gradually no longer being applied clinically. Years of research have shown that the risk of sudden cardiac death in psychotic patients is associated with drug use, and antipsychotic drugs have certain cardiotoxicity and can induce arrhythmias. The mechanism of antipsychotic-induced sudden cardiac death is complicated. Highly cited papers are among the most commonly used indicators for measuring scientific excellence. This article presents a high-level analysis of highly cited papers using Web of Science core collection databases, scientometrics methods, and thematic clusters. Temporal dynamics of focus topics are identified using a collaborative network (author, institution, thematic clusters, and temporal dynamics of focus topics are identified), keyword co-occurrence analysis, co-citation clustering, and keyword evolution. The primary purpose of this study is to discuss the visual results, summarize the research progress, and predict the future research trends by bibliometric methods of CiteSpace and VOSviewer. This study showed that a research hotspot is that the mechanisms of cardiotoxicity, the safety monitoring, and the assessment of the risk-benefit during clinical use of some newer antipsychotics, clozapine and olanzapine. We discussed relevant key articles briefly and provided ideas for future research directions for more researchers to conduct related research.