Research hotspots and frontiers of alcohol and epilepsy: A bibliometric analysis

Abstract Purpose Alcohol is implicated in epileptogenesis and seizures attack. An increasing number of studies about alcohol and epilepsy have been published. We aimed to assess research trends and hot spots in the field of alcohol and epilepsy. Patients and Methods Literature concerning alcohol and epilepsy was systemically searched through the Web of Science database. Collaborative maps were quantitatively analyzed by using the VOSviewer and CiteSpace tools. Results A total of 1578 papers about the field of alcohol and epilepsy were taken into analysis, which was written by 6840 authors from 2153 institutions in 85 countries, published in 676 journals, and cited 79 667 references from 10 750 journals. The United States was the leading country and had close ties with others. The University of Toronto was the most productive institution. Alcoholism‐clinical and experimental research was the fastest‐growing journal. Richard J. Bodnar was the author contributing the most literature. Analysis of keywords showed epilepsy, alcohol, seizures, alcohol withdrawal, and management were common themes. Conclusion The presented study conducted the first bibliometric analysis of the field of alcohol and epilepsy, which will provide insights into the latest progress, evolution paths, frontier research hot spots, and future research trends in the field.


| INTRODUC TI ON
7][8][9][10] The International League Against Epilepsy (ILAE) proposed alcohol intake as one of the risk factors for epilepsy and advised patients to refrain from drinking. 9,11,12The role of alcohol in epileptogenesis and seizures attack also attribute great attention from scientific researchers.The field of alcohol and epilepsy is booming, with increasing output.However, the papers in this field have not been quantitatively analyzed by a bibliometrics approach, which will provide an overview and help in exploring the research frontiers from the quantified perspective.
In this study, we conducted the first bibliometric analysis in the field of alcohol and epilepsy, which explored the hot spots and frontiers over the past 30 years and generated the corresponding knowledge maps.This study provided insights into the latest progress, evolution paths, frontier research hot spots, and future research trends in the field.

| Data source and retrieval strategy
This study retrieves all available articles until December 31, 2022, from the Web of Science database (SCI-EXPANDED & SSCI), which covers the oldest publications with firm coverage.The search formula is "ALL = ((epilepsy OR seizure) AND (liquor OR alcohol))".
Duplicate results were manually removed.

| Data analysis and visualization
Through scientific mapping procedures, researchers can visually analyze the structure, dynamic patterns, and trends of the field, which can help in identifying the evolution path, classical literature, and the frontier of the discipline. 131][22][23] The parameter setting of CiteSpace was Method (LLR), Time Splicing

| The scientific outcome in the field of alcohol and epilepsy
A total of 1578 papers were retrieved for analysis.These papers were written by 6840 authors from 2135 institutions in 85 countries, were published in 676 journals, and cited 79 667 references from 10750 journals.

| Analysis of publication years
The annual publications were on an increased trend, especially after 2007 (Figure 1).The number of annual publications increased from 19 in 1993 to 67 in 2022 with a peak of 88 papers in 2021.

| Analysis of institutions
The top 10 institutions contributed 143 publications (9.06%) (Table 1).Seven of the top 10 institutions were from the United States, with the remaining three from Canada, Germany, and the Britain, respectively.The collaboration between institutions was shown in Figure 3A.The University of Toronto and Boston University had the closest cooperation with other institutions.To fully understand the collaborative relationships between countries and institutions, we visualized their collaboration by the CiteSpace tool.The USA was the home to most institutions and articles (Figure 3B).These findings showed that the USA and its institutions may play critical roles in the field of alcohol and epilepsy.

| Analysis of journals
The 1578 papers taken into analysis in this study were published in 676 journals.Table 2 listed the top 10 high-output journals.The journal with the highest impact factor (IF) was Neurology.The journal with the most published was Alcoholism-clinical and experimental research (n = 66), followed by Epilepsia (n = 42) and Epilepsy & behavior (n = 41).Among these journals, five of the top 10 were neurology-related, three were alcohol-related, and the remaining two journals were Pharmacyrelated and Multidisciplinary sciences-related, respectively.

| Analysis of co-cited journals
Co-citation is the frequency with that two articles are cited together. 24By establishing the structure of the pattern of linkages among papers, the co-citation provides a tool for monitoring the development of scientific fields and assessing the degree of the interrelationship among specialties. 24The more frequently the journals are co-cited, the closer their academic relationship. 24,25The top 10 co-cited journals are shown in Table 3, among which Epilepsia had the most frequencies of co-citations (2639 times).The top 100 journals, being co-cited by at least 144 times, were used for the analysis through the VOSviewer tool.The network can be divided into three main clusters, including clinical medicine, pharmacology, and neurosciences (Figure 4A).

| Analysis of authors
The number of published papers represents the author contributions and research activities in a field. 26Table 4 showed the top 10 authors with the most published papers.Richard J. Bodnar ranked first (n = 16, 2.34%), followed by Lutz G. Schmidt (n = 11, 1.61%) and Sara N. Bleich (10, 1.46%).We used CiteSpace to visualize the authors and institutions included in the literature.The University of Toronto has the most authors in this field (Figure 5).
Uncoincidentally, Richard J. Bodnar also has the closest cooperation with others.

TA B L E 1
The top 10 productive countries and institutions.| 347 LIU et al.

| Analysis of co-cited authors
The top 10 co-cited authors published more than 81 papers in the field (Table 4).W. Allen Hauser ranked first, with 87 co-citations, followed by Marc A. Schuckit, John T. Sullivan, Howard C. Becker, and Michael F. Mayo-Smith.And the co-cited authors mapping was shown in Figure 6.W. Allen Hauser had the greatest number of cocitations and collaborated closely with other authors.

| Analysis of references
The top five most cited references and their first authors were presented in Table 5.These references were published between 2004 and 2017, and four of five were published after 2014.The most highly cited paper (14 times) was written by Marc A. Schuckit, entitled Recognition and management of withdrawal delirium (delirium tremens). 27

| Analysis of co-cited references
Since 1993, there are a total of 79 667 co-cited references in the field, which were average co-cited 51 times per article.Among them, Assessment of Alcohol Withdrawal: the revised clinical institute withdrawal assessment for alcohol scale (CIWA-Ar) had the highest number of citations (n = 78) (Figure 7A and Table 6). 28In the co-cited networks, this article was also the most influential research, sharing strong relationships with the rest of the literature.The top 25 cocited references with the strongest citation bursts were shown in Figure 7B, and the burst strength of these ranged from 3.59 to 7.65.
The strongest ones (Strength = 7.68) came from Marc A. Schuckit, entitled Recognition and management of withdrawal delirium (delirium tremens). 29

| Analysis of keywords
High-frequency keywords in articles reflect the hot spots of a research field. 30The top five keywords were epilepsy (290, TLS = 1675), alcohol (247, TLS = 1604), seizures (193, TLS = 1203), alcohol withdrawal (113, TLS = 830), and management (104, TLS = 644) (Table 7).The VOSviewer was used to color the keywords according to the average time of occurrence.The keywords, illness, stress, and dopamine transporter, were emerging as a hotspot of fields in recent years (Figure 8A).We also provided the timeline view for the major clusters in Figure 8B.It shows the evolutionary

| DISCUSS ION
2][33][34] Alcohol, as one of the common cause inducing seizures, has garnered growing interest from researchers.This study quantified scientific productions, The types of journals reflect the different research directions. 35,36The papers were mainly published in neurology-related journals.The research was also published in other kinds of journals, including pharmacology, biochemistry, and behavioral journals.The existence of researcher groups in different fields was conducive to interdisciplinary communication.
By analyzing the highly productive authors and co-cited authors, we found Thomas Sander, Lutz G.Schmidta, and Helmut Harms all belonging to the Free University of Berlin.8][39] Some emerging scholars also pay attention to the field.Yulin Zhao and his collaborators were working on G-protein-gated inwardly rectifying K+ (GIRK) channels and seizures.They found that alcohol mitigates the effects of a convulsant in acute epilepsy mouse models by activating GIRK channels. 40 F I G U R E 5 Network visualization of authors and institutions, which circles represent the authors or institutions, the circle sizes represent the number of publications, and the links represent the relationship between the authors and the institutions.
epileptic patients. 41The emerging scholars were devoted to alcohol and epilepsy, but the literature analysis showed limited cooperation and exchanges between each other.In the future, more cooperation and communication are needed to promote research in the field.
The top 10 productive countries were almost developed, contributing more than 80% of the papers.The USA, with the majority of top institutions, led international collaborations.Studies on alcohol and epilepsy were weaker in Asia, which also has a lot The analysis of keywords showed that epilepsy, alcohol, seizures, alcohol withdrawal, and management were the most frequently used keywords in research articles in this area.It is worth mentioning that alcohol withdrawal and management were also the focus of the field.3][44][45] Reducing alcohol intake gradually, rather than abruptly, may help prevent alcohol-withdrawal seizures. 46Meanwhile, Downtown Emergency Services Center (DESC) in Seattle, Washington has already implemented alcohol management as a harm reduction strategy.Other countries and institutions may need to pay more attention to alcohol management.
Drinking can induce seizures.Intake of alcohol may make the patients miss the antiepileptic drugs or reduce the efficacy of medications.Surprisingly, small doses of alcohol can help to reduce anxiety and stress, which prevent seizures. 47,48Large doses of alcohol may increase γ-aminobutyric acid (GABA) ergic activity with stimulation of the GABA receptor-mediated Cl−, which can increase the risk of seizures. 42,49,50However, the specific cutoff for alcohol intake remains undetermined.The values of drinking in epileptic patients warrant further studies.

| Strengths and limitations
This study also had certain limitations.First of all, our data are only from the Web of Science (SCI & SSCI), which may need to be more comprehensive.In the next place, we screened the English articles, so that articles published in other languages were not included.

| CONCLUSION
This study conducted a quantitative and visual analysis in the field of

(
1993-2022), Text Processing (all term source), and Node types (choose the node we need).We determined the parameter settings for the VOSviewer according to the data type, data source, and the selected analysis and counting methods.The Centrality reflects the value of nodes in the networks (Centrality >0.1, indicating having an important influence).
showed the close cooperative relations among countries by the VOSviewer tool.F I G U R E 1 Schematic illustration of analysis of publication years.F I G U R E 2 Schematic illustration of analysis of countries.(A) Top 20 countries productivity in included literature; (B) Country collaboration map, where circles denote countries, and lines denote their collaborations.
The top three were the University of Toronto (21, Centrality = 0.03), Oregon Health and Science University (20, Centrality = 0.01), and Columbia University in the City of New York (15, Centrality = 0.02).

Figure
Figure 4B illustrated the topic distribution of the journals through the dual map overlay.We found three main citation paths.These three paths indicated that studies published in Molecular, Health, and Psychology were often cited by those published in Immunology, Dentistry, and Medicine.
Schematic illustration of analysis of institutions.(A) Institution collaboration map; (B) Network visualization of countries and institutions, which circles represent the institutions and the countries to which belong, the size of the circles represents the number of published papers, the colors of the circles represent the different years of publications, and the connecting lines represent the cooperation between institutions.

F I G U R E 4
Schematic illustration of analysis of co-cited journals.(A) The co-citation journal visualization network can be divided into three different clusters (red clustering represented the journal of clinical, green represented the journal of pharmacology, and blue was for that of neurosciences); (B) The dual-map overlay and corresponding disciplines, which left side of the map shows journals, and the right side shows cited journals.Different colored paths show the flow and connection of knowledge from different research fields.countries, institutions, journals, authors, references, and keywords, which may help in identifying the latest progress, evolution paths, frontier research hot spots, and future research trends in this field.This study covered all available articles until December 31, 2022, from the Web of Science database.The annual growth rate was 16.46% based on the number of published articles in 1993.It presented an increasing trend, reflecting that research in the field was gradually becoming a hot pot.

F I G U R E 6 TA B L E 5
Network visualization of co-cited authors, where the node represents the author, the size represents the number of articles published, and the node line represents the strength of association.Top five references.withdrawal delirium an evidence-based practice guideline [J] Michael F. Mayo-Smith F I G U R E 7 Schematic illustration of analysis of co-cited references.(A) The density visualization map of co-cited references based on VOSviewer.The color closer to yellow indicates a higher influence, while blue indicates a lower influence.(B) Burst strength and time duration of the top 25 references with the strongest citation bursts.ofdrinkers.It was indicated that the international distribution of this field was imbalanced.This may be related to the developed economy and high investment in healthcare in developed countries.Therefore, it is necessary to increase the research investment of the Asian countries and cooperation with the developed countries.

TA B L E 7
alcohol and epilepsy.With the help of CiteSpace and VOSviewer, we have a deeper understanding of the latest progress, evolution paths, frontier research hot spots, and future research trends in the field.And the field of epilepsy and alcohol research has received extensive attention from countries and institutions, especially the United States.Critical factors associated with alcohol and epilepsy, such as alcohol withdrawal and management, also become hot spots in the field.The dose of alcohol that epileptics need to control will be the focus of future research.Overall, our results will help researchers understand the research trend, and provide clues for future research directions in the field.TA B L E 6 Top five co-cited references.withdrawal: the revised clinical institute withdrawal assessment for alcohol scale (CIWA-Ar) to the medical literature: XIII.How to use an article on economic analysis of clinical practice B. What are the results and will they help me in caring for my patients?abstinence in the genesis of alcoholic epilepsy [J] Maurice Victor Top five co-cited references.

F I G U R E 8
Schematic illustration of analysis of keywords, topics, and themes.(A) The average publication year; (B) Timeline view of the eight clusters.The location of the node indicates the time the keywords first appeared, and the lines indicate the relationships between them.
Top 10 journals for co-citation.
TA B L E 2 The top 10 most productive journals published.TA B L E 3 pathway in the study of alcohol and epilepsy.Eight core keywords were arranged as forms of timelines vertically, including epilepsy, seizure susceptibility, alcohol dependence, delirium treatment, oxidative stress, chromosomal toxicity, delta-opioid receptor, and health services utilization.Each timeline covered a series of keywords.