The data were retrieved online through the Science Citation Index-Expanded version of the Web of Science Core Collection (WoSCC). All data were obtained on 27 January 2024 and spanned the period from 2004 to 2024.

The following terms were searched in the topic: ‘Gastric Ulcers’ or ‘Gastrohelcosis’ or ‘Gastrohelcoma’ or ‘Stomach Ulcers’; the language choice was English; and only original articles and reviews were included. Two independent investigators reviewed the titles and abstracts, and studies unrelated to gastric ulcers were excluded. After reviewing titles and abstracts, 13,372 publications were retained. The detailed retrieval process is shown in Figure 1.

Bibliometrics is a method used to assess research in a target area through an objective and reliable structured analysis of large amounts of information (5, 6). CiteSpace is a scientific software that is usually used to summarise existing results in a target area and to identify future research directions by analysing research trends in the literature (7). CiteSpace combines bibliometrics and data mining algorithms with visual analytics to analyse and present potential knowledge and research hotspots in the form of images (8). It provides information about authors, countries/regions, institutions, keywords, journals, etc., and performs co-occurrence, co-citation, and cluster analyses on related information in image form to visualise research trends and patterns and to mine the correlations between the information in each part of the literature (9). It can either comprehensively reflect the research status of a discipline or explore a discipline from different directions, helping researchers quickly and accurately understand the research hotspots and research trends in the field and so on. VOSviewer is an application used to build and view bibliometric maps (10). It analyses and summarises data and information to present an overview of the research in the field in the form of graphs, thereby objectively presenting the current status of research in a certain field. Therefore, with the help of CiteSpace and VOSviewer visualisation and analysis software, this study collected, analysed, and processed literature information in related fields, drew images and tables related to this topic, and sorted the current status of research on gastric ulcers and hotspot issues, which can be used as a reference for treatment and future research.

Based on the adopted data and statistical purposes, corresponding visualisation graphs can be generated in CiteSpace, where different nodes and links exist in different graphs, and nodes with high centrality are indicated as research hotspots or turning points in the field (11). We conducted a relevant literature search of the WoSCC and exported the retrieved data in a plain text format; the export included complete records and references. The exported file was named download_XXX.txt and was imported into CiteSpace 6.2. R7 for bibliometric and visualisation analyses. Cluster analysis of co-occurring keywords was performed using CiteSpace to reveal major themes. The contour function (Sihouette, S) is commonly used to assess clustering, which is generally considered reasonable if S > 0.5, and S > 0.7 indicates a high degree of homogeneity among cluster members, suggesting that the clustering results are meaningful.

In this study, the data were time-sliced in years, the node filter was g-indexed, and the k value was set to five.

After screening, we downloaded 13,372 publications from the WoSCC database. Figure 2 shows a bar dash plot of the number of publications and citation frequency for the topic of gastric ulcers from 2004 to 2024.

Figure 3 shows the visualisation and analysis of the country collaboration network, which generated 112 nodes and 145 links, respectively. According to the statistics, the eight countries with the highest number of publications published a total of 9,208 articles (68.9%). When analysing country centrality, Russia was found to have the highest mediator centrality (0.89; Table 1).

The analysis of institutions and agencies generated 235 nodes and 259 links (Figure 4), and the top 10 institutions and agencies published 1,524 articles (11.4%), with the top five being the Egyptian Knowledge Bank, University of California, US Department of Veterans Affairs, Veterans Health Administration, and Baylor College of Medicine (Table 2).

Figure 5 shows a bi-mapped overlay mapping of journals, representing the distributional relationship between citing and cited journals as well as the development of relationships between different disciplines (12). The citing journals are located on the left side; the cited journals are located on the right side; the coloured paths indicate the correlation between citations; and the coloured nodes represent the clustering of different disciplines.

Figure 6 illustrates the author network generated by CiteSpace, where the connecting lines between nodes signify the collaborative relationships among authors. The thicknesses of these lines denote the frequency of collaboration, with thicker lines indicating greater cooperation. Complementing this visual representation, Table 3 lists the top ten authors with the highest number of publications, who collectively contributed 442 papers (3.3% of the total publications).

Table 4 shows the top 10 studies related to gastric ulcers, which were cited 1,339 times. The rise, growth, and decline of a research field can be observed by clustering co-cited literature, with more documents in a cluster indicating greater importance of the clustered field. Figure 7 shows the sequence plot of the top 10 co-cited documents plotted as nodes for each time slice.

Keyword frequency reflects research hotspots in a field, and high-centrality keywords represent milestones for advancing research in the field. Table 5 lists the top 10 high-frequency and high-centrality keywords.

This field of research focuses on high-frequency keywords. High-centrality keywords reflect the status and influence of the corresponding content in the research field whereas co-occurring keywords extracted from the selected literature can reflect research hotspots and development trends in a certain field. Figure 8A shows the 242 symbiotic keywords extracted from the 13,372 manuscripts included in this study

Figure 8B shows a timeline plot of keyword clustering, where the 13 cluster names labelled # represent basic knowledge in the field of gastric ulcer research and its evolution over time, and the connecting lines in the figure indicate that two keywords occurred simultaneously in the same article. The mean contour value (Sihouette, S) is typically used to evaluate the clustering. In general, clusters are considered reasonable if S > 0.5, while an S value of 0.7 implies that the clusters are highly plausible. We obtained 13 clusters with cluster contour values greater than 0.7, indicating that the results are highly plausible.

Explosive keywords reflect the research frontiers in different periods. Figure 9 shows the 15 keywords with the highest explosion rates between 2004 and 2024. The red line indicates the time period when the keywords exploded, and the blue line indicates the time interval (13).

Clustering of keywords can be used to summarise a topic, and the analysis of keyword clustering can be used to identify hot topics in a research field. We summarised the 15 clusters generated and found that the hot topics of research in the field of gastric ulcers included the following three aspects: predisposing factors, pathogenesis, and diagnostic and therapeutic options for gastric ulcers.

The pathogenesis of gastric ulcers is complex, and many risk factors can lead to the development of this disease. Helicobacter pylori, ethanol, bariatric surgery, and non-steroidal anti-inflammatory drugs (NSAIDs) in the keyword clustering were common factors that contributed to gastric ulcers, and significant temporal and geographic differences were observed in these factors. The prevalence of many gastrointestinal disorders does not remain constant but increases and decreases (22). A European study found an underlying birth cohort trend in gastric ulcers, and this emergence is likely shaped by an underlying trend in Helicobacter pylori infection (23). However, the incidence, hospitalisation, and mortality rates of gastric ulcer-related diseases have decreased worldwide over the past few decades (22, 24, 25).

Although the clinical manifestations of most gastric ulcers are similar, their pathogenesis appears to be dramatically different owing to different pathogenic factors. For example, inflammation associated with Helicobacter pylori infection can present with two different manifestations, either too little or too much gastric acid secretion, culminating in different types of ulcers (26). These effects can be mediated by cytokines that inhibit mural cell secretion, or by the activation of calcitonin gene-related peptide (CGRP) sensory neurones coupled with growth inhibitory hormone stimulation and inhibition of histamine secretion to acutely inhibit gastric secretion and form gastric ulcers (22, 27). Another important factor contributing to ulcer development is that, unlike Helicobacter pylori, which colonises the stomach, NSAIDs can damage the gastroduodenal mucosa via a holistic mechanism. Inhibition of cyclooxygenase 1 (COX-1), a prostaglandin-derived enzyme, is thought to be the main mechanism by which NSAIDs damage the mucosa (28). Nevertheless, while Helicobacter pylori infection, NSAID use, or post-bariatric surgery complications and stress are distinct risk factors that contribute to gastric ulcers through different mechanisms, their effects ultimately manifest as damage to the gastric epithelium (29–32). Therefore, the study of injury mechanisms, including gastric epithelial cell injury, has become a focus in gastric ulcer research.

Since the pathogenesis of gastric ulcers is determined by the pathogenic factors, the therapeutic strategies are dependent on the pathogenesis. For example, antibiotic treatment is the first choice for gastric ulcers caused by Helicobacter pylori infection. In contrast, NSAID-mediated gastric mucosal injury is often treated with drugs that inhibit gastric acid secretion and neutralise luminal acidity, effectively preventing gastric ulcers (33, 34). However, several issues have emerged over time. Declining eradication rates of Helicobacter pylori, increasing rates of multidrug resistance in children, adverse reactions associated with the extensive use of proton pump inhibitors (PPIs), a gradual increase in the number of idiopathic ulcers, and a number of other factors have prompted an urgent search for new therapeutic approaches (35–37).

Breaking keywords represent the research frontiers of a discipline over time, and an analysis of these keywords can yield predictions and indicate future research trends for the corresponding discipline. We found a clear temporal trend in the research on gastric ulcers. In the early stage of research, the diagnosis and classification of gastric ulcers were studied, such as ‘Peptic ulcer’, ‘Duodenal ulcer’, ‘Increased rise’ and so on. Later, researchers conducted cellular-level studies, shifting their focus to pathogenic factors and cellular damage, such as ‘Helicobacter pylori’ and ‘gastric epithelial cells’. More recently, researchers have focused on studying pathogenic factors and cellular damage through studies related to pathogenesis, therapeutic means and sequelae of treatment, such as ‘Antioxidant’, ‘Marginal ulcer’, ‘Gut microbiota’, and ‘Antibiotic resistance’.

In this study, we utilised CiteSpace software to analyse and visualise gastric ulcer data from 2004 to 2024, summarising key issues and trends in gastric ulcer research. However, the inherent limitations of this study require consideration. First, our analysis was limited to data sourced exclusively from the Web of Science Core Collection (WoSCC), potentially leading to the exclusion of relevant literature from other databases. Second, this study was restricted to English-language sources, which may have resulted in the omission of significant findings and perspectives from non-English-speaking countries. Future studies should aim to address these limitations by incorporating a broader range of databases and including literature in multiple languages.