
==== Front
Medicine (Baltimore)
Medicine (Baltimore)
MD
Medicine
0025-7974
1536-5964
Lippincott Williams & Wilkins Hagerstown, MD

39312337
MD-D-24-03681
00038
10.1097/MD.0000000000039754
3
6600
Research Article
Observational Study
Critical care in older adults: Research landscape and hotspots from a bibliometric perspective
Du Zhe MD drdz01@163.com
a
Li Fang MD a*
https://orcid.org/0000-0002-5279-9737
Wang Tianbing MD a
a Trauma Center, Peking University People’s Hospital, National Center for Trauma Medicine, Key Laboratory of Trauma and Neural Regeneration (Ministry of Education), Beijing, China.
* Correspondence: Fang Li, Trauma Center, Peking University People’s Hospital, No.11 South Xizhimen Street, Beijing 100044, China (e-mail: lifang1927@yeah.net).
20 9 2024
20 9 2024
103 38 e3975406 4 2024
26 5 2024
29 8 2024
Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.
2024
https://creativecommons.org/licenses/by-nc/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial License 4.0 (CCBY-NC), where it is permissible to download, share, remix, transform, and buildup the work provided it is properly cited. The work cannot be used commercially without permission from the journal.

As the population ages, there will be an increasing demand for health care resources, particularly in intensive care. Therefore, critically ill older adults are receiving increasing attention and have been extensively studied. However, the research landscape, dynamic patterns, and emerging topics in this area have scarcely been reviewed. This study aimed to delve into the current status and emerging trends (publication volume and research topics) in critical care for older adults (including interventions, outcomes, and complications) using bibliometric analysis. We retrieved original articles and reviews focusing on critical care for older adults published between 2013 and 2022 from the Web of Science core database. To examine and present the research trends, we employed VOSviewer and CiteSpace software for analysis and visualization. The cooperative network of countries and institutions, cocited authorship network, cocited references, and cooccurrence network of keywords were analyzed. Overall, 6356 articles and reviews published between 2013 and 2022 were analyzed, revealing a noticeable upward trend in the number of publications focused on critical care for older adults. In total, 34,654 authors from 7989 institutions across 131 countries collaborated to publish 6356 papers related to critical care for older adults in 1715 academic journals. The United States of America and China were the top contributors in terms of research studies, while Bertrand Guidet was the most prolific author with the highest number of articles. A dual-map overlay of the literature revealed that research papers published in Molecular/Biology/Genetics and Health/Nursing/Medicine journals were frequently referenced in Medicine/Medical/Clinical journals. Older patients with coronavirus disease 2019, delirium, and frailty were new trends and developing areas of interest. This is the first bibliometric study focusing on critical care in older adults. The research topics indicate that a comprehensive geriatric assessment, tailored interventions, and specific therapeutic algorithms among older adults are recommended to improve outcomes. Furthermore, this study provides valuable insights for clinical decision-making, guideline development, and resource allocation in critical care settings.

bibliometric analysis
CiteSpace
critical care
older adults
visualization
VOSviewer
OPEN-ACCESSTRUE
==== Body
pmc1. Introduction

Owing to the increase in life expectancy and a decrease in birth rates, the global population has seen a shift, with currently more adults aged > 65 years than children aged < 5 years since 2018.[1] Furthermore, the percentage of the population aged > 80 years in North America is expected to double, reaching 9% of the total population.[2] As the population ages, there will be an increasing demand for health care resources, particularly in intensive care.[3] Patients aged > 65 years comprise approximately two-thirds of total intensive care unit (ICU) bed days in high-income countries.[1,3] Critically ill older patients are at a higher risk of experiencing organ dysfunction and increased mortality due to conditions such as circulatory shock, acute kidney injury, mechanical ventilation, and sepsis than their younger counterparts.[1,4] The multiorgan physiological effects of aging, in addition to other complexities, such as frailty and preexisting comorbidities, must be considered for these patients in the ICU.[5] Moreover, older adults are particularly susceptible to the impact of the COVID-19 pandemic, with advancing age being a significant risk factor for severe illness and the need for ICU admission due to the disease.[6,7] According to the World Health Organization, 46% of the global excess mortalities associated with COVID-19 (i.e., 6.8 million) occurred among individuals aged between 65 and 84 years.[8] These examples underscore the severity of the challenges faced by this population; therefore, using a holistic and comprehensive approach to their care in all health care settings is important.[9] Critically ill older adults are receiving increasing attention and have been extensively studied. However, the research landscape, dynamic patterns, and emerging topics in this area have scarcely been reviewed.

Bibliometric analysis is a powerful technique that can be utilized to evaluate any research topic, anticipate emerging trends, and uncover research frontiers within the realm of science.[10] The analysis results can be presented in the form of statistical tables or graphs, providing a clear visualization of hotspots, trends, author collaboration networks, institutional partnership networks, and article correlation analysis.[11] Bibliometric analysis has been used in similar contexts in previous studies; for example, Tang et al[12] reported the application of artificial intelligence in intensive care medicine using bibliometric analysis. Zhang et al[13] analyzed publications on early mobilization in ICU. Therefore, in this study, we performed a bibliometric analysis of the literature concerning critically ill older patients over the last decade to delve into the research landscape and identify the key areas of focus within this topic. We aim to enrich the current knowledge base and pave the way for new research avenues.

2. Materials and methods

2.1. Retrieval strategy

Data were retrieved from the Web of Science Core Collection on August 15, 2023. The selected search terms were based on the Medical Subject Heading term “critical care” and terms similar to “older adults.” The search formula was as follows: Topic = (“older people” OR “older patient*” OR “older adult*” OR “older person*” OR “the aged” OR “the elderly” OR “senior*” OR “elder*”) AND (“critical care” or “intensive care”). The study period covered the years 2013 to 2022 (recent 10 years), focusing on original articles and reviews for publication. Non-English papers were not included in the analysis.[14] The screening process is illustrated in Figure 1.

Figure 1. Flow chart of the screening process.

2.2. Data analysis

VOSviewer (v.1.6.19; https://www.vosviewer.com/) and CiteSpace (v.6.1.R2; https://citespace.podia.com/) were used for statistical computation and graphics. VOSviewer was used to visualize the network map of the coauthorship of authors, countries, and institutions, as well as the cooccurrence of keywords. The range of authors/countries/institutions per document was set as 5 to 25, and the minimum number of occurrences of a keyword was set as 5. CiteSpace was utilized to analyze and visualize the dual-map overlay of journals, cocited references, reference clustering and bursts, and timeline views of references. Additionally, keyword clustering and bursts were also examined using CiteSpace. The journal citation reports, 2022 impact factor, and journal citation report division of the analyzed journals were sourced from the Web of Science.

2.3. Ethics approval and consent

This study involved the analysis of publicly available data from the Web of Science. It involved no animal or human participants; therefore, ethical approval was not required.

3. Results

3.1. Temporal distribution map of publications and citations

A total of 6356 publications on critical care for older adults were included in this study. Output steadily increased from 2013 to 2022, with the most publications in 2021 (output number: 1101) and only slight decreases in 2016 and 2022 (Fig. 2). The number of citations also increased annually from 2013 to 2022, with the most citations in 2022 (citation number: 23,347).

Figure 2. The number and trend of annual publications.

3.2. Visual analysis of countries/regions and institutions

VOSviewer was utilized to create a collaborative network encompassing 131 countries where the studies had been published. The minimum inclusion threshold was established at 5 documents per country, with 80 countries meeting this criterion (Fig. 3A). Each node represents 1 country, and links between nodes represent cooperation, with wider links indicating a higher level of collaboration.[15] As shown in Table 1, The United States of America (USA) led with the highest number of studies, contributing 1647 documents, accounting for 25.91% of the total; following closely behind were China and England, with 555 (8.73%) and 443 (6.97%) documents, respectively. In addition, the USA had the most citations (39,097), and England had the highest total link strength (1056).

Table 1 Top 10 most productive countries.

Rank	Country/regions	Count	Citations	Total link strength	
1	USA	1647	39,097	849	
2	People Republic of China	555	9798	180	
3	England	443	13,978	1056	
4	Turkey	406	1391	70	
5	Canada	345	10,205	371	
6	France	322	6686	820	
7	Germany	319	6476	816	
8	Australia	314	7305	409	
9	Italy	292	11,808	658	
10	Japan	269	3125	72	

Figure 3. Network visualization map of the main research countries and organizations related to critical care in older adults; cooperative network of countries (A) and institutions (B).

VOSviewer was utilized to construct a collaborative network comprising 7989 associated institutions, with a minimum inclusion threshold of 5 documents per institution. A total of 761 institutions satisfied this criterion, as shown in Figure 3B. Each node in the visualization represents an institution, with its size reflecting the number of published studies. The connections between nodes signify collaboration, with wider links denoting stronger collaboration.[15] Table 2 presents the top 10 most productive institutions. Leading the list is the Mackay Memorial Hospital with 134 publications, closely followed by the University of Toronto with 117 publications and Harvard Medical School with 83 publications.

Table 2 Top 10 most productive institutions.

1	Institutions	Count	Citations	Total link strength	
2	Mackay Memorial Hospital	134	691	224	
3	University of Toronto	117	2744	456	
4	Harvard Medical School	83	2077	288	
5	Mackay Medical College	77	308	167	
6	Vanderbilt University	75	5512	176	
7	University of Pittsburgh	68	2606	156	
8	University of Washington	66	2121	184	
9	Monash University	66	1295	211	
10	University of California San Francisco	60	2667	180	

3.3. Visual analysis of authors

VOSviewer was utilized to create a collaborative network comprising 34,654 authors within this field, with a minimum inclusion threshold set at 5 documents per author; 244 authors met this threshold (Fig. 4). The top 10 most productive authors are detailed in Table 3. Bertrand Guidet from Hôpital Saint-Antoine emerged as the most prolific author in this field with 30 publications, closely followed by Hans Flaatten from the University of Bergen with 25 publications and Christian Jung from Heinrich Heine University with 21 publications. Sean M. Bagshaw from the University of Alberta stood out as the most cited author in this field.

Table 3 Top 10 most productive authors.

Rank	Authors	Country	Affiliation	Count	Citations	Total link strength	
1	Bertrand Guidet	France	Hôpital Saint-Antoine	30	1095	260	
2	Hans Flaatten	Norway	University of Bergen	25	864	254	
3	Christian Jung	Germany	Heinrich-Heine-University	21	716	245	
4	E. Wesly Ely	USA	Vanderbilt University Medical Center	19	1160	64	
5	Sean M. Bagshaw	Canada	University of Alberta and Alberta Health Services	19	1660	60	
6	Dylan W. De Lange	The Netherlands	University Utrecht	18	775	197	
7	Wojciech Szczeklik	Poland	Jagiellonian University Medical College	16	642	235	
8	Antonio Artigas	Spain	Hospital Universitari Parc Taulí	14	871	191	
9	Ariane Boumendil	France	Hôpital Saint-Antoine	14	783	178	
10	Jesper Fjolner	Denmark	Aarhus University Hospital	14	620	219	

Figure 4. Cocited authorship network in the research field of critical care in older adults.

3.4. Visual analysis of journals

Table 4 lists the top 10 most productive journals in research focusing on critical care for older adults. The International Journal of Gerontology led with the highest number of articles published (431 publications), followed by BMJ Open (87 publications) and the Cureus Journal of Medical Science (86 publications). Eight of the 10 journals were classified as Q1 or Q2 journals, with Critical Care boasting the highest impact factor of 15.1.

Table 4 Top 10 most productive publication sources.

Rank	Journal	Count	Citations	JCR	IF (2022)	JCR category	
1	International Journal of Gerontology	431	1953	Q4	0.3	Geriatrics and Gerontology	
2	BMJ Open	87	979	Q2	2.9	Medicine, General and Internal	
3	Cureus Journal of Medical Science	86	185	Q3	1.2	Medicine, General and Internal	
4	PLOS One	83	1306	Q2	3.7	Multidisciplinary Sciences	
5	Critical Care Medicine	77	3122	Q1	8.8	Critical Care Medicine	
6	Journal of the American Geriatrics Society	73	2464	Q1	6.3	Geriatrics and Gerontology	
7	Journal of Critical Care	60	1075	Q2	3.7	Critical Care Medicine	
8	Critical Care	58	3222	Q1	15.1	Critical Care Medicine	
9	BMC Geriatrics	43	523	Q2	4.1	Geriatrics and Gerontology	
10	Journal of Clinical Medicine	43	281	Q2	3.9	Medicine, General and Internal	
IF = impact factor, JCR = journal citation reports.

A dual-map overlay provides a domain-level perspective on the expansion of literature and clustering of citations based on their reference paths.[16] Figure 5 showcases a dual-map overlay illustrating articles focused on critical care for older adults published between 2013 and 2022. The 2 green citation pathways indicate that the papers published in Molecular/Biology/Genetics and Health/Nursing/Medicine journals were frequently cited by Medicine/Medical/Clinical journals.

Figure 5. The dual-map overlay of journals publishing articles on critical care in older adults.

3.5. Visual analysis of cocited references

Figure 6A visually represents the cocitations of the citing articles, first authors, and publication years of the most cited publications pertaining to critical care in older adults. Table 5 presents the detailed information on the top 10 cited publications. The publication that received the highest number of cocitations was a research article titled “Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study” by Zhou et al, published in The Lancet[17]; the second-most cited article was “The impact of frailty on ICU and 30-day mortality and the level of care in very elderly patients (≥80 years),” published in Intensive Care Medicine by Flaaten et al.[18]

Table 5 Top 10 cocited references.

Rank	Title	Journal	Year	Cocitation	
1	Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study	Lancet	2020	152	
2	The impact of frailty on ICU and 30-day mortality and the level of care in very elderly patients (≥80 years)	Intensive Care Medicine	2017	105	
3	The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3)	JAMA	2016	102	
4	The impact of frailty on intensive care unit outcomes: a systematic review and meta-analysis	Intensive Care Medicine	2017	97	
5	Delirium in elderly people	Lancet	2014	95	
6	Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China	Lancet	2020	95	
7	Characteristics of and important lessons from the coronavirus disease 2019 (COVID-19) outbreak in China summary of a report of 72,314 cases from the Chinese Center for Disease Control and Prevention	JAMA	2020	92	
8	Clinical characteristics of coronavirus disease 2019 in China	New England Journal of Medicine	2020	87	
9	The status of intensive care medicine research and a future agenda for very old patients in the ICU	Intensive Care Medicine	2017	73	
10	Long-term cognitive impairment after critical illness	New England Journal of Medicine	2013	72	
ICU = intensive care unit.

Figure 6. Visual analysis of cocited references in critical care in older adults; (A) reference cocitation network; (B) clustering network; (C) top 20 references with the strongest citation bursts; and (D) timeline of cocited references.

The 11 largest clusters extracted from the references of the included articles are displayed in Figure 6B. The cluster labels are popular noun phrases extracted from the article title using a logarithmic likelihood ratio algorithm, including COVID-19 patient (#0), postoperative delirium (#1), pharmacological treatment (#2), old patient (#3), critical illness (#4), elderly patient (#5), septic patient (#6), ICU utilization (#7), bloodstream infection (#9), nationwide cohort study (#11), and coronary artery bypass (#16). The purple and blue nodes symbolize early clustering labels associated with older patients and ICU utilization, while the red and yellow nodes represent more recent clustering labels, such as COVID-19 patients and postoperative delirium.

We identified the 20 most “bursty” references in Figure 6C. The cocitation burst began in 2013 and lasted into 2022, with the highest strength being 30.14 (“Delirium in elderly people” by Inouye et al). In 2022, we observed 4 bursty references, all of which pertained to the clinical characteristics of patients with COVID-19 in Wuhan, China.[17,19–21]

A timeline view can be utilized to visually track the evolution and advancement of research hotspots throughout time.[16] As shown in Figure 6D, clusters #2 (pharmacological treatment), #9 (bloodstream infection), and #11 (nationwide cohort study) started early but terminated in 2016, whereas clusters #0 (COVID-19 patient), #1 (postoperative delirium), #3 (old patient), and #6 (septic patient) are still ongoing, indicating the frontiers in this research area.

3.6. Keyword analysis of trending research topic

Author keywords extracted from titles and abstracts were analyzed using VOSviewer for in-depth examination. A total of 16,738 keywords were extracted, with 816 and 157 appearing > 10 and > 50 times, respectively. As shown in Figure 7 and Table 6, “mortality” emerged as the predominant term, with 1466 cooccurrences, closely followed by “outcomes,” “elderly patients,” “intensive care units,” and “COVID-19.” In Figure 7A and 7B, author keywords are color-coded based on their average publication years, providing a visual representation of the temporal distribution of key terms in the literature. The larger the number of items in the neighborhood of a point and the higher the weights of the neighboring items, the closer the color of the point is to yellow. “COVID-19,” “delirium,” “frailty,” “mortality,” and “intensive care unit” are highlighted yellow and green, indicating hot research topics. Figure 7C shows the cluster network map of high-frequency keywords. Clusters #0 (end-of-life care) and #1 (delirium) were recent clusters of high-frequency keywords. Figure 7D highlights the top 20 keywords with the most significant citation bursts, shedding light on the trending topics in the research field; “COVID-19” had the strongest burst (strength = 124.77) and lasted into 2022, followed by “severe acute respiratory syndrome coronavirus 2” (strength = 35.03) and “coronavirus” (strength = 16.46).

Table 6 Top 20 keywords.

Rank	Keywords	Occurrences	Total link strength	
1	Mortality	1466	10,305	
2	Outcomes	889	6456	
3	Elderly patients	650	5164	
4	Intensive care unit	647	4936	
5	COVID-19	547	2124	
6	Elderly	533	3551	
7	Risk	506	3353	
8	Management	480	2973	
9	Risk factors	458	3252	
10	Impact	451	3270	
11	Intensive care unit	380	2694	
12	Critical care	377	2736	
13	Epidemiology	337	2267	
14	Older adults	333	2609	
15	Frailty	330	2661	
16	Surgery	322	2133	
17	Critically ill patients	318	2682	
18	Care	317	2042	
19	Intensive care	313	2214	
20	ICU	299	2467	
ICU = intensive care unit.

Figure 7. Cooccurrence network of keywords; (A) network visualization; (B) density visualization; (C) clustered network of cooccurring keywords on critical care in older adults; and (D) top 20 keywords with the strongest citation bursts.

4. Discussion

4.1. General information

This groundbreaking bibliometric study is the first to specifically investigate critical care in older adults, providing valuable insights into this important area of research. After completing the screening process, we successfully identified a total of 34,654 authors affiliated with 7989 institutions across 131 countries. These authors collectively published 6356 papers in 1715 academic journals focusing on critical care for older adults between 2013 and 2022.

The USA, China, and England published the highest number of studies on critical care for older adults, underscoring their prominent role in this field of research. We also found significant interconnections between the countries, indicating a robust level of collaboration. International collaborations can facilitate knowledge exchange, resource sharing, and the development of innovative solutions to address common challenges in caring for older patients. The Mackay Memorial Hospital emerged as the leading publisher of academic papers, closely followed by the University of Toronto and Harvard Medical School. Among the top 10 most productive institutions, 6 were from the USA, underscoring the country’s significant impact in this research field.

The researchers publishing in this area appear to be categorized into 2 distinct clusters with limited connections, suggesting a lack of academic collaboration among researchers from various countries. Bertrand Guidet from the Hôpital Saint-Antoine was the most productive author. Dr Guidet has worked on studies related to very old critically ill patients, mainly on mortality in critically ill older patients in the ICU,[22,23] clinical treatment of old ICU patients,[24–26] outcomes of older patients with COVID-19,[27–29] and multicenter studies on critically ill older patients.[30,31]

Eight of the top 10 journals publishing studies in this field were ranked as Q1 or Q2 journals, underscoring the significance and prominence of this research area as a current focal point. The top 10 cocited references predominantly center around the following 2 key themes: the characteristics of patients with COVID-19 in critical care and critical care for older patients in the ICU. These themes also serve as indicators of the current research hotspots and frontiers within the research field.

4.2. Research hotspots and emerging topics

The analysis of high-frequency keywords reveals the current hotspots within a specific research field.[32] We aimed to provide a comprehensive overview of the research trends in critical care for older adults through a detailed analysis of reference clusters (Fig. 6B), bursts (Fig. 6C), timeline views (Fig. 6D), keyword cooccurrences (Fig. 7A and 7B), keyword clusters (Fig. 7C), and keyword bursts (Fig. 7D). We identified the following 3 main research hotspots in this area: older patients with COVID-19, delirium, and frailty.

Older patients with COVID-19 are an emerging topic of research in this field. The COVID-19 pandemic has led to a sharp and significant rise in hospitalizations for pneumonia accompanied by multiorgan complications.[33] Extensive global research indicates that advanced age stands out as the primary risk factor for severe COVID-19 and its associated health complications, such as hospitalization, ICU admission, and mortality.[6] Individuals in the 65 to 74 and ≥ 85-year-old age groups were 65 and 340 times more likely to succumb to COVID-19, respectively, than their younger counterparts, underscoring the significantly greater impact on older adults.[34] This suggests that hospitals need to open more ICU beds and equip more doctors for older patients with COVID-19. Doctors also need to invest more energy in the management of older patients with COVID-19. Therefore, personalized care plans based on a comprehensive geriatric assessment, tailored interventions, and specific therapeutic algorithms among older adults are thus recommended to improve the outcomes.[35] Age-related immune system remodeling, known as immunosenescence, is widely recognized as a key factor contributing to the heightened vulnerability to infections in older individuals.[6] Novel therapies that enhance the immune system can provide crucial support for older individuals with underlying health conditions in combating the acute form of COVID-19.[36]

Furthermore, delirium was another important topic in our analysis. Delirium, an acute disorder affecting attention and cognition, is a frequently encountered, potentially life-threatening condition that can usually be prevented in older individuals.[37] It is a prevalent surgical complication in older adults, with a higher incidence of 15% to 25% following major elective surgery and 50% after high-risk procedures, such as hip fracture repair and cardiac surgery.[38] In the ICU, >75% of patients receiving mechanical ventilation experience a combination of delirium, stupor, and coma.[39] Advanced age, dementia, functional limitations, and a significant burden of other health conditions are frequently observed as predisposing factors. The contributing factors encompass medications, surgical procedures, anesthesia, elevated pain levels, anemia, infections, sudden onset of illness, and acute flare-ups of chronic conditions.[40] Comprehensive and coordinated care provided by physicians, nurses, and other health care providers, as well as involvement from family members, plays a crucial role in reducing the likelihood of complications and adverse outcomes frequently observed in individuals with delirium. Guidelines for the prevention and management of delirium in hospitalized older patients have been meticulously crafted by the United Kingdom National Institute for Health and Care Excellence in collaboration with the American Society for Enhancing Geriatric Understanding and Expertise among Surgical and Medical Specialists.[41,42]

Frailty was the third most popular topic in this research area. It is characterized by an increased susceptibility to stressors due to a diminished reserve and functionality of various physiological systems[43] and is a noteworthy and escalating concern, particularly with the expanding population of older adults.[44] Frailty is common in patients admitted to the ICU and is associated with worsened outcomes. Therefore, identifying this previously unrecognized and vulnerable ICU population should act as the impetus for investigating and implementing appropriate care plans for critically ill patients with frailty. Moreover, further research is required to determine modifiable factors that could improve outcomes for critically ill patients with frailty.[45]

This study had some limitations. First, we only extracted articles from the Web of Science database; therefore, more databases, such as Google Scholar, should be considered for data collection.[46,47] Nevertheless, the Web of Science Core Collection database is a well-structured and diversely indexed database that is among the most widely used databases in various scientific fields, and the quality of papers in this data source is recognized and widely used in most scientometric studies.[48] Second, only publications in the English language were included[49]; articles published in other languages were not considered, possibly overlooking important global perspectives and findings.[50] Third, a significant portion of our results relied on machine algorithms with minimal manual induction and organization.[51] Nevertheless, literature analysis based on visualization can effectively help researchers understand the hotspots and emerging trends of critical care in older adults.

5. Conclusion

This study provides a comprehensive insight into the current research landscape, emerging hotspots, and upcoming trends in critical care for older adults, drawing from articles published in the past decade. The results show that “older COVID-19 patients,” “delirium,” and “frailty” will be key areas of future research. These research topics indicate a comprehensive geriatric assessment, tailored interventions, and specific therapeutic algorithms among older adults are recommended to improve the outcomes. Furthermore, this study provides valuable insights for clinical decision-making, guideline development, and resource allocation in critical care settings.

Acknowledgments

The authors are grateful to the professional editors at Editage, for providing excellent assistance in the production of this manuscript.

Author contributions

Writing – original draft: Zhe Du.

Data curation: Fang Li.

Conceptualization: Tianbing Wang.

Writing – review & editing: Tianbing Wang.

Abbreviations:

ICU intensive care unit,

USA United States of America

This study was supported by Peking University People’s Hospital Scientific Research Development Funds (grant numbers: RDJ2022-31 and RDJP2022-06).

The authors have no conflicts of interest to disclose.

All data generated or analyzed during this study are included in this published article [and its supplementary information files].

How to cite this article: Du Z, Li F, Wang T. Critical care in older adults: Research landscape and hotspots from a bibliometric perspective. Medicine 2024;103:38(e39754).
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