Overall development trend of childhood adversity and anxiety research

This study systematically conducted a bibliometric analysis of research on childhood adversity and anxiety disorders based on three major international databases. The results show that this field has undergone an evolution from long-term slow accumulation to rapid growth in the past two decades. Since 2000, the number of related studies has consistently increased, with a notable acceleration after 2010, reflecting the growing academic recognition of childhood adversity as a significant risk factor for anxiety disorders. This development trend aligns closely with the shift in the paradigm of mental health research, where the focus has gradually shifted from adult symptomatology to emphasizing the long-term impact of early life experiences on the onset and development of mental disorders.

It is worth noting that the rapid growth in publication volume has not been driven by a single discipline but is the result of the interdisciplinary integration of psychiatry, psychology, public health and neuroscience, providing a more multidimensional research perspective for understanding the complex etiology of anxiety disorders. At the same time, international attention to mental health issues has steadily increased in the past two decades, especially after the COVID-19 pandemic, with global multicenter cohort studies, longitudinal follow-up studies and big data analysis rapidly accumulating (Madigan et al., Reference Madigan, Racine, Vaillancourt, Korczak, Hewitt, Pador, Park, McArthur, Holy and Neville2023). Existing systematic reviews and empirical studies indicate that anxiety levels among children and adolescents generally increased during the pandemic, and individuals with a history of childhood adversity showed higher anxiety risk when faced with pandemic-related stress (Lian et al., Reference Lian, Kiely, Callaghan and Anstey2024; Kalia and Knauft, Reference Kalia and Knauft2025). Furthermore, the standardization of ACE assessment tools, the deepening of multidisciplinary collaboration models and the continued emphasis on adolescent mental health in public health policy have all contributed to the rapid development of this research area (Singirankabo et al., Reference Singirankabo, Niyonsenga, Kibaki, Ntete and Mutabaruka2025).

Country and institution distribution: Research landscape dominated by Europe and North America

Analysis of the country and institution distribution shows that the United States holds a dominant position in childhood adversity and anxiety research, not only leading in publication volume and citation frequency but also occupying central positions in high-impact journals and core research institutions. Notably, the research framework represented by ACE was first proposed and promoted in the United States, laying a crucial foundation for subsequent large-scale population studies and interdisciplinary expansion (Felitti et al., Reference Felitti, Anda, Nordenberg, Williamson, Spitz, Edwards, Koss and Marks1998; Anda et al., Reference Anda, Felitti, Bremner, Walker, Whitfield, Perry, Dube and Giles2006). Additionally, sustained funding from institutions such as the National Institutes of Health (NIH) for mental health and life course research has significantly facilitated high-output and high-impact studies in this field (Insel, Reference Insel2009).

At the same time, European countries such as Germany, the Netherlands and the United Kingdom have shown outstanding performance in terms of publication impact and international collaboration, forming a relatively stable and high-quality research network. This may be related to their emphasis on multicenter collaboration, cross-national cohort sharing and public health-oriented research models (Viner et al., Reference Viner, Ozer, Denny, Marmot, Resnick, Fatusi and Currie2012). In contrast, while developing countries such as China have experienced rapid growth in publication volume in recent years, their overall citation frequency and international influence still need improvement, suggesting that there remains a regional imbalance in childhood adversity and anxiety research globally. This also reflects the uneven distribution of research resources, data foundations and international collaboration opportunities. This geographic distribution pattern suggests that the existing body of evidence may predominantly reflect patterns of adversity exposure and anxiety phenotypes within Western sociocultural contexts, and therefore, the cross-cultural generalizability of these findings requires further validation. Meanwhile, these results should be interpreted with caution, as factors such as differences in database coverage, language bias and publication practices may also, to some extent, influence the observed geographic disparities.

Evolution of research themes: From trauma types to cross-diagnosis and mechanistic integration

Based on keyword co-occurrence, clustering and time-overlay analysis results, it is evident that the themes in childhood adversity and anxiety research have shown clear stages of evolution. The research framework in this stage was mainly based on traditional psychiatric classification systems, aiming to identify the risk roles of different trauma experiences in the formation of specific anxiety disorders. Among these, Brewin et al. conducted a meta-analysis systematically summarizing various independent risk factors for post-traumatic stress disorder (PTSD), revealing the stable predictive roles of childhood adversity, previous trauma history and psychiatric history across different populations. They also pointed out that most risk factors had relatively limited effect sizes, while factors during or after trauma (such as trauma severity, lack of social support and additional life stress) had more significant impacts. This study provided an important methodological foundation for early research on the risk factors in childhood adversity and anxiety disorders (Brewin et al., Reference Brewin, Andrews and Valentine2000). On this basis, Cougle et al. further explored the specific associations between childhood physical and sexual abuse and different anxiety disorders through data from the National Comorbidity Survey. They found that, after controlling for depression, other anxiety disorders, parental anxiety history and demographic variables, childhood sexual abuse had independent associations with social anxiety disorder, panic disorder, generalized anxiety disorder and PTSD, while the association of physical abuse was more limited, mainly concentrated in PTSD and specific phobias. Moreover, the study also revealed gender differences, suggesting that different types of childhood abuse may affect anxiety outcomes through different pathways in males and females. Overall, the research in this period aimed to clarify “which types of trauma corresponded to which anxiety disorder.” This work, to some extent, contributed to the empirical accumulation of the relationship between childhood adversity and anxiety, and also gradually revealed the limitations of excessive reliance on trauma types and diagnostic categories, paving the way for the subsequent shift toward a comprehensive adversity concept and a cross-diagnostic perspective (Cougle et al., Reference Cougle, Timpano, Sachs-Ericsson, Keough and Riccardi2010).

As research continued to accumulate, keyword clustering and co-occurrence structures showed that different types of childhood adversity exhibit high co-occurrence and overlap at the psychopathological level, and single trauma or single diagnosis could no longer fully explain the complex presentation of anxiety-related symptoms. In this context, the research focus gradually shifted toward the comprehensive concept of ACE, emphasizing the cumulative effects of childhood adversity and overall risk exposure. This shift was initiated by the pioneering research of Felitti et al., who first systematically proposed the ACE framework. They revealed that multiple forms of childhood abuse and family dysfunction often coexist and show stable dose–response relationships with various health risk behaviors and diseases in adulthood, thus breaking the traditional research paradigm of explaining long-term health outcomes with a single traumatic event (Felitti et al., Reference Felitti, Anda, Nordenberg, Williamson, Spitz, Edwards, Koss and Marks1998). Subsequently, Anda et al., based on ACE research, further integrated epidemiological and neurobiological evidence, pointing out that cumulative exposure to ACEs might affect brain structure and function by continuously activating the stress response system, and is broadly associated with emotional, substance use and multisystem health outcomes. This evidence strengthened the theoretical foundation for viewing childhood adversity as a cross-diagnostic and cross-system risk factor (Anda et al., Reference Anda, Felitti, Bremner, Walker, Whitfield, Perry, Dube and Giles2006). From a developmental psychology and methodological perspective, the cumulative risk model proposed by Evans et al. provided an important supplement to ACE research, emphasizing that exposure to multiple risk factors has a greater impact on individual development than a single risk factor. This perspective aligns with the bioecological model, the chronic stress homeostasis model and evolutionary developmental theories, providing a more integrative theoretical framework for understanding the widespread and enduring effects of childhood adversity (Evans et al., Reference Evans, Li and Whipple2013). Overall, the shift from single trauma types to ACE and cumulative risk models significantly promoted comparative and integrative research across disorders and symptoms, and laid the theoretical foundation for subsequent attention to emotion regulation, psychological resilience and multi-pathway mechanisms.

In recent years, keyword time-overlay and burst analysis further show that the focus of childhood adversity and anxiety research has gradually expanded from traditional diagnostic classifications and specific trauma type descriptions to emotional regulation processes, psychological resilience, cross-diagnostic risk factors and symptom-level analysis frameworks. This change reflects the researchers’ growing focus on the psychological mechanisms between early adversity and anxiety outcomes, rather than just the direct associations between exposure and diagnosis. In this research orientation, emotional susceptibility traits have gradually become a focus of study. McLaughlin et al.’s research, for example, proposed that anxiety sensitivity is an important risk factor for the development of anxiety symptoms in adolescents and adults, and further pointed out that stressful life events could promote the occurrence and exacerbation of anxiety symptoms by increasing anxiety sensitivity. Longitudinal studies have shown that anxiety sensitivity mediates the relationship between stress exposure and changes in anxiety symptoms, and this effect is somewhat specific to anxiety symptoms, not fully applicable to depression symptoms. Such studies provide key psychological evidence for understanding how childhood adversity affects anxiety risk through emotional processing and cognitive response patterns (McLaughlin and Hatzenbuehler, Reference McLaughlin and Hatzenbuehler2009). Meanwhile, research hotspots have gradually extended to the effects of childhood adversity on brain structure and function. McLaughlin et al.’s “deprivation–threat” theoretical framework, proposed in 2014, emphasizes that different types of adverse environmental experiences may affect emotional and behavioral outcomes through different neurodevelopmental pathways (McLaughlin et al., Reference McLaughlin, Sheridan and Lambert2014). This framework distinguishes between deprivation (lack of expected environmental input) and threat (involving harm to the individual’s physical or psychological integrity), and points out that using traditional stress response pathways to explain the neural effects of childhood adversity has limitations. This model provides a more integrative theoretical perspective for explaining how childhood adversity affects anxiety-related symptoms through multiple neural and psychological mechanisms. Overall, the shift from emotional regulation traits to neurodevelopmental dimensions reflects the paradigm shift from single diagnosis-oriented research to cross-diagnostic and cross-level mechanism integration, providing a more systematic explanatory framework for understanding the onset, maintenance and heterogeneity of anxiety symptoms.

Methodological shift: From correlational studies to complex systems perspectives

CiteSpace burst analysis further reveals a significant shift in the methodological orientation of this field. In recent years, keywords such as “network analysis,” “epidemiology” and “resilience” have continuously burst, indicating that research on childhood adversity and anxiety is gradually shifting from univariate or linear association analysis to complex systems and multilevel modeling perspectives. This trend reflects the researchers’ attempts to break through the limitations of traditional latent variable models and understand the psychopathological process in a more dynamic and structured way. In this context, Borsboom et al.’s symptom network theory provides an important methodological foundation for conceptualizing mental disorders. This theory suggests that mental disorders are not driven by a single latent cause but arise from direct interactions between symptoms; when these interactions are strong enough, a symptom network can form a self-sustaining feedback structure, manifesting as a stable mental disorder state (Borsboom, Reference Borsboom2017). Although symptom network theory has not yet developed into a fully mature unified theory of psychopathology, its perspective on the dynamic relationships between symptoms provides a new analytical framework for understanding the heterogeneity, resilience and susceptibility of anxiety disorders. On this basis, researchers have begun to incorporate childhood adversity into symptom network models, exploring its potential “bridging” or amplifying role between different symptoms, thus expanding the explanatory space of adversity research at the symptom level and viewing childhood adversity not only as a distal risk factor but as a key regulatory node in the network structure. Meanwhile, the burst emergence of biologically related keywords (such as DNA methylation, neural circuits and gene–environment interactions) suggests that the field is also advancing parallel explorations of biological mechanisms. Research such as Pollok et al.’s imaging meta-analysis shows a relatively consistent association between early life adversity and structural changes in brain regions such as the hippocampus, amygdala and anterior cingulate cortex, with age and adversity type-specific effects (Pollok et al., Reference Pollok, Kaiser, Kraaijenvanger, Monninger, Brandeis, Banaschewski, Eickhoff and Holz2022). These studies provide important clues for understanding the neural basis of childhood adversity’s impact on anxiety and related emotional disorders. Additionally, Heim et al.’s systematic review of early life stress further points out that early adversity may have long-lasting effects on the emotional regulation system through sensitive period effects, gene–environment interactions and epigenetic mechanisms, thereby increasing the risk of mental disorders in adulthood. These findings reinforce the theoretical basis for viewing childhood adversity as a cross-level biological-psychological risk factor (Heim and Binder, Reference Heim and Binder2012). However, despite the significant progress in network models and biological mechanism research, both remain relatively scattered in terms of time series, research design and theoretical integration. Compared with epidemiological and clinical association studies, a stable and unified multilevel integration framework has not yet been established. These results suggest that future research urgently needs to strengthen interdisciplinary collaboration based on complex systems approaches, systematically integrating symptom network structures, neurobiological mechanisms and evidence of social environmental exposures to deepen the overall understanding of the relationship between childhood adversity and anxiety.

High-citation literature and core authors: Foundational contributions and focus

High-citation literature analysis shows that the theoretical frameworks and empirical foundations in childhood adversity and anxiety research have been shaped primarily by a few seminal studies. From a global citation perspective, high-impact articles are mainly concentrated on neurobiological modeling of anxiety and trauma-related disorders, and the systematic integration of childhood adversity as a broad risk factor for mental disorders, reflecting the early developmental stage of this field, focused on theoretical construction and methodological integration. In terms of neurobiological mechanisms, Etkin et al.’s functional neuroimaging meta-analysis ranks first in global citations, systematically integrating brain function abnormalities in PTSD, social anxiety disorder and specific phobias in emotional processing. This study revealed the common neurobiological basis of anxiety disorders and normal fear responses in the overactivation of the amygdala and insula, while pointing out some specificity in PTSD regarding functional reduction in the anterior cingulate cortex and ventromedial prefrontal cortex. This study, by synthesizing heterogeneous research results, provided a unified neuroimaging framework for the common and specific neurobiological mechanisms of anxiety disorders, laying the important groundwork for subsequent research. Following this, Shin et al.’s systematic review of the neural circuits of anxiety disorders further confirmed that the fear circuit model proposed in animal fear models and human emotional processing studies could explain the enhanced amygdala and insula responses in various anxiety disorders, while PTSD shows a characteristic reduction in the regulatory functions of the anterior cingulate cortex and ventromedial prefrontal cortex. These studies strengthened the amygdala–prefrontal cortex–hippocampus pathway hypothesis for anxiety disorder neural circuits and highlighted key issues such as whether functional abnormalities are risk susceptibility factors or disease consequences (Milad et al., Reference Milad, Pitman, Ellis, Gold, Shin, Lasko, Zeidan, Handwerger, Orr and Rauch2009; Shin and Liberzon, Reference Shin and Liberzon2010). Early imaging studies, such as Bremner et al.’s PET study on Vietnam War veterans, revealed functional abnormalities in areas such as the medial prefrontal cortex and anterior cingulate cortex in PTSD patients from the perspective of trauma cue processing, suggesting that brain region changes related to emotional regulation, memory processing and threat response are crucial neural bases for PTSD symptoms (Bremner et al., Reference Bremner, Staib, Kaloupek, Southwick, Soufer and Charney1999). Overall, these high-citation studies surrounding fear circuits, extinction learning and trauma cue processing have collectively established the mainstream research paradigm for explaining anxiety and trauma-related disorders through neuroimaging and fear conditioning models, providing key theoretical and methodological support for integrating childhood adversity into neurobiological research on anxiety disorders.

Meanwhile, in the field of childhood adversity research, Chen et al.’s systematic review and meta-analysis integrated large-scale population evidence, systematically assessing the association between childhood sexual abuse and lifelong mental disorder diagnoses, clearly pointing out the robust relationship between childhood sexual abuse and the significantly increased risk of anxiety disorders, depression, PTSD and suicide attempts. This research provided an important evidence base for childhood adversity as a broad risk factor for mental disorders, marking the transition from fragmented association studies to systematic evidence integration in the field (Chen et al., Reference Chen, Murad, Paras, Colbenson, Sattler, Goranson, Elamin, Seime, Shinozaki, Prokop and Zirakzadeh2010). Building on this, McLaughlin et al.’s “stress sensitization hypothesis” further explained how childhood adversity increases the risk of mental disorders by altering individual sensitivity to subsequent stress exposure, providing a theoretical framework for understanding the long-term association between childhood adversity and adult mental disorders. This theory has become an important theoretical anchor for linking epidemiological evidence with psychological and biological mechanisms in research. As the research focus shifted from single disorder risk to psychopathological structures themselves, Lamers et al. revealed the highly stable comorbidity pattern between anxiety and depression disorders in the NESDA cohort, noting that comorbidity was closely related to more childhood trauma experiences, higher susceptibility traits and more severe and persistent clinical manifestations (McLaughlin et al., Reference McLaughlin, Conron, Koenen and Gilman2010; Lamers et al., Reference Lamers, van Oppen, Comijs, Smit, Spinhoven, van Balkom, Nolen, Zitman, Beekman and Penninx2011). These studies highlight the limitations of traditional single-diagnosis frameworks in explaining complex real-world psychopathological structures and provide key empirical evidence for cross-diagnostic research. On this basis, Caspi et al.’s “p factor” model represents a significant milestone in the shift from categorical diagnosis to cross-diagnostic and dimensional models in psychopathology research. The model emphasizes that multiple mental disorders share the same risk factors and biological foundations, with early adverse experiences, such as childhood adversity, potentially influencing multiple disorder outcomes by increasing overall susceptibility to psychopathology (Caspi and Moffitt, Reference Caspi and Moffitt2018). The introduction of the “p factor” not only provides a theoretical explanation for the high comorbidity of anxiety, depression and other disorders but also further promotes the shift of childhood adversity research from disorder-specific analysis to cross-diagnostic risk mechanism integration. Overall, this series of high-citation studies outlines the clear research evolution from broad risk identification of childhood adversity to the systematic characterization of comorbidity structures and to the construction of cross-diagnostic and dimensional theoretical models. This highlights the limitations of single-diagnosis frameworks in explaining complex psychopathological structures and has had a profound impact on subsequent cross-diagnostic and mechanism integration research.

Compared to global high-citation literature, local citation analysis presents a more focused and consistent research orientation. In the literature sample of this study, the most cited articles primarily focus on the direct link between childhood adversity/abuse and anxiety disorders, particularly clinical and epidemiological evidence of anxiety disorder subtypes, such as panic disorder, social anxiety disorder and generalized anxiety disorder. This feature indicates that local high-citation literature plays a key role in solidifying the core empirical line and refining disorder-specific risk patterns. Safren et al.’s research, for example, systematically compared the prevalence of childhood physical or sexual abuse in different anxiety disorder diagnoses and found that childhood abuse was significantly higher in panic disorder patients compared to social anxiety disorder patients, with generalized anxiety disorder patients falling in between. Additionally, a history of childhood abuse was also associated with a higher risk of comorbid major depression in anxiety disorder patients. This type of study emphasizes that childhood adversity not only affects the onset risk of anxiety disorders but also closely relates to symptom severity and comorbidity structures. In the domain of social anxiety disorder, Simon et al.’s research further showed that childhood abuse had a higher prevalence among treatment-seeking generalized social anxiety disorder patients, with different types of abuse (especially emotional abuse and neglect) showing cumulative effects, correlating with more severe social anxiety symptoms and poorer functional outcomes. These findings highlight the important role of childhood adversity in the heterogeneity within anxiety disorder subtypes (Safren et al., Reference Safren, Gershuny, Marzol, Otto and Pollack2002). Meanwhile, although Etkin et al.’s functional neuroimaging meta-analysis holds a core position in global citations, it also appears frequently in local citations, reflecting the important reference value of neuroimaging evidence in explaining childhood adversity-related anxiety symptoms (Etkin and Wager, Reference Etkin and Wager2007). These studies provide critical neurobiological insights into the commonalities and specificities of emotional processing and regulation circuits in different anxiety disorder subtypes. At the population level, research by Cougle, Goodwin and McLaughlin based on large-scale epidemiological data from the National Comorbidity Survey and others has systematically verified the independent association between childhood physical and sexual abuse and the risk of anxiety disorders in adulthood, and further proposed mechanisms such as stress sensitization to explain how childhood adversity increases the risk of anxiety and related mental disorders by enhancing individual sensitivity to subsequent stress events. The high citation frequency of these studies in local literature emphasizes their key role in bridging clinical observations with population-based evidence (Goodwin et al., Reference Goodwin, Fergusson and Horwood2005; Cougle et al., Reference Cougle, Timpano, Sachs-Ericsson, Keough and Riccardi2010; McLaughlin et al., Reference McLaughlin, Conron, Koenen and Gilman2010). Additionally, Spinhoven et al.’s analysis of the shared and specific effects of childhood adversity on anxiety and depression disorders represents an early manifestation of the cross-diagnostic perspective in local literature. However, their research still focuses on the differentiated relationship between types of adversity and specific disorder phenotypes (Spinhoven et al., Reference Spinhoven, Elzinga, Hovens, Roelofs, Zitman, van Oppen and Penninx2010). Overall, global high-citation literature tends to reflect foundational contributions in theoretical modeling and the construction of cross-diagnostic frameworks, while local high-citation literature reveals a growing focus on more specific and stable patterns of association between childhood adversity and anxiety disorders. This difference suggests that, although the cross-diagnostic perspective is becoming increasingly important in psychopathological research, disorder-specific mechanisms related to anxiety disorder subtypes still hold irreplaceable research value in the study of childhood adversity and anxiety.”

Insights and research frontiers

Overall, research on childhood adversity and anxiety has evolved from an early descriptive association phase to a mature research field that integrates multiple layers and methods. The bibliometric results show that this field has not only expanded in research topics from specific trauma types to cumulative adversity and cross-diagnostic perspectives but also shifted significantly in methodology from cross-sectional correlation analysis to longitudinal, mechanism-oriented and complex systems modeling. Based on the main findings of this study, future research can further deepen in the following directions. First, strengthening research on non-Western and underdeveloped regions is an important prerequisite for enhancing the generalizability and public health value of the field. Currently, high-output countries and influential institutions are still mainly concentrated in Europe and North America, with research samples having certain homogeneity in terms of sociocultural context, family structure, adversity types and coping resources. This structural bias may limit the applicability of research conclusions in different cultural and social contexts. Future studies should conduct more high-quality epidemiological and longitudinal research in regions such as Asia, Africa and Latin America, systematically comparing the manifestations, exposure patterns and impact pathways of childhood adversity on anxiety disorders across different cultural contexts, thereby constructing a more globally representative theoretical framework. Second, combining longitudinal study designs with multimodal data will help clarify the time series and potential causal pathways of childhood adversity’s impact on the occurrence and development of anxiety. Although a large body of research has confirmed the robust association between childhood adversity and anxiety risk, most of the evidence is still based on retrospective or cross-sectional designs, making it difficult to distinguish between risk susceptibility, disease consequences and mediating mechanisms. Future research could use prospective cohort designs, integrating psychological measurements, neuroimaging, physiological indicators and molecular biology data, to dynamically track individuals’ psychological and biological changes from childhood to adulthood, providing a more detailed understanding of critical windows for adversity exposure, cumulative effects and their influence on anxiety symptom trajectories. Third, further integrating network analysis, psychological resilience models and biological mechanism research will provide new opportunities for translating risk identification into intervention targets. The rise of symptom network models in recent years has allowed researchers to understand the internal structure and dynamic interactions of anxiety disorders at the symptom level, while resilience research provides an important perspective for explaining why individuals show different outcomes under similar adversity exposure. Future research should incorporate resilience-related variables into the network analysis framework, along with biological evidence, such as neural circuits, epigenetics and gene–environment interactions, to identify the “nodes” or “bridging mechanisms” that play a key regulatory role in the childhood adversity–anxiety pathway. This integrated approach will not only deepen understanding of the heterogeneity of anxiety disorders but also lay the foundation for the development of precise prevention and individualized intervention strategies. Overall, the bibliometric analysis of this study reveals the systematic evolution of childhood adversity and anxiety research in terms of themes, methods and theories. Future research, if breakthroughs are made in cross-cultural sample expansion, longitudinal causal mechanism analysis and multilevel integration models, is expected to drive the field from risk association descriptions to mechanism explanation and intervention translation, providing a more solid scientific foundation for the early identification and prevention strategies for anxiety disorders.

Limitations

This study still has several limitations that should be interpreted with caution. First, this study employed a bibliometric method, and the analysis was limited to published literature, which is influenced by publication bias to some extent. Unpublished research, gray literature and non-English literature were not systematically included, which may lead to biased estimates of the research scale, topic distribution and impact. Second, although this study integrated three major databases (Web of Science Core Collection, Scopus and PubMed), it still could not fully cover all relevant research, especially regional journals or studies published in local languages. Therefore, the results of this study mainly reflect the research landscape under the international mainstream academic discourse system, rather than the global picture. Third, bibliometric analysis was based primarily on titles, abstracts, keywords and citation information, which cannot deeply assess the heterogeneity in research design, sample sources, childhood adversity measurement tools, anxiety disorder diagnostic criteria and statistical methods in the included studies. Therefore, the research hotspots and evolutionary trends presented in this study reflect changes in academic focus, rather than the strength of specific effect sizes or causal relationships. Fourth, this study is a cross-sectional bibliometric analysis and cannot directly infer causal pathways or temporal sequences between childhood adversity and anxiety disorders. Although some highly cited studies based on longitudinal cohort or mechanistic research have proposed theoretical hypotheses, this study itself did not reanalyze the original data, and its conclusions should be understood as descriptive and comparative evidence. Fifth, differences in the literature inclusion standards, keyword indexing rules and citation statistics between different databases may affect the publication volume, citation frequency and collaboration network structure. Although this study minimized such biases through deduplication and standardization, the impact could not be completely eliminated. Finally, although tools like CiteSpace and VOSviewer provide effective means to reveal research structures and theme evolution, their results still rely on parameter settings and algorithm assumptions, and different analytical strategies may lead to variations in the number of clusters and theme boundaries. Therefore, the related visualization results should be regarded as auxiliary interpretations of research trends rather than a strict categorization of research themes.