In total, n = 4669 articles were retrieved from WoS database. After manually deleting non-Asian publications (n = 731) or those published in 2023 (n = 34), a total of 3904 Asian BMS-related publications were identified between 1980 and 2022. Notably, these 43 years witnessed a significant upward trend in publication output on BMS, from a single paper in 1980 to 574 papers in 2022 (Fig. 1a). The publication frequency markedly surged around 2010, followed by a decline after 2020 (Fig. 1a).

Bariatric metabolic surgery research publication trends in Asian countries. a Yearly publication count from 1980 to 2022. b Geographical distribution of publications across Asia. c Annual publication count of the top five prolific countries from 1980 to 2022. d Geographical distribution of publications across China

Across 29 Asian countries contributing to the field of BMS research (n = 3904 in total), China emerged as the leading contributor with 1221 articles (Fig. 1b). China’s publications rose from a single paper in 1982 to 195 papers in 2022 (Fig. 1c). In fact, China’s annual publication volume displayed an upward trend, and consistently lead Asia in this respect since around 2010 (Fig. 1c).

Table 1 outlines the top 15 most prolific countries in Asia in terms of BMS research, and the full list of 29 contributing countries is shown in Supplementary Table 2. The bulk of the research emerges from East Asia and the Middle East. China (1221, 31.28% of 3904) leads the pack, followed by Turkey (562, 14.40%), Israel (502, 12.86%), Saudi Arabia (276, 7.07%), and India (247, 6.33%). Notably, China also topped the list in terms of citation frequency with a total of 18,009 citations, succeeded by Israel, India, Turkey, South Korea, and Japan.

When adjusted for population, Israel, Singapore, Lebanon, Kuwait, and Qatar emerged as leaders with more than 15 publications per million inhabitants. In contrast, China’s figures were relatively low, with only 0.85 publications per million inhabitants (Table 1). It is notable that China (in Taiwan Province) was the first Asian country to report on BMS (in 1974), and Turkey and Saudi Arabia were early adopters of laparoscopic BMS (in 1995) (Supplementary Table 2).

With respect to annual volume, the top five prolific countries demonstrated consistent growth trends until 2020, the time when COVID-19 emerged, after which a significant decline was noted (as depicted in Fig. 1c).

Within China, the provinces contributing the most were Taiwan, Shanghai, Jiangsu, Beijing, Guangdong, and Shandong, each contributing over 70 articles (Fig. 1d). These provinces are primarily located in the eastern region, where the most productive institutions are situated.

After adjusting for population, Taiwan, Shanghai, Hong Kong, and Beijing demonstrated a relatively higher number of publications per million inhabitants, while Guangdong’s prominence significantly diminished (Supplementary Table 3).

The correlation between research productivity, as gauged by article count, and GDP per capita across countries was found to be weak (R = 0.092, p = 0.63, Supplementary Fig. 1a). However, within China, a strong correlation was found between research productivity and both regional GDP (R = 0.51, p < 0.01; Supplementary Fig. 1b), and regional GDP per capita (R = 0.74, p < 0.001; Supplementary Fig. 1c).

Across the 43-year period, a total of 2914 institutions contributed to BMS research. As shown in Table 2, the majority of the top 20 institutions are universities, with Tel Aviv University from Israel leading the group with 181 articles. The second most productive institution was Min-Sheng General Hospital from Taiwan, China, contributing 107 articles. Notably, half of these top 20 institutions are affiliated with China.

Tel Aviv University’s papers were the most frequently cited, amassing 3545 total citations, while Min-Sheng General Hospital achieved the highest average citation number per paper (30.20) (Table 2). Supplementary Fig. 2 provides a citation analysis of prolific institutions that have produced at least 20 articles. The figure presents four main clusters: Cluster 1, indicated by red nodes, consists mostly of universities from mainland China; Cluster 2, denoted by blue nodes, is dominated by institutions from Taiwan, China; Cluster 3, represented by yellow nodes, contains organizations from Israel; and Cluster 4, marked by green nodes, comprises institutes from Iran and Saudi Arabia.

Within China, 744 institutions contributed to BMS research within the study period. The ten most productive of these, mostly universities, are displayed in Supplementary Table 4. Min-Sheng General Hospital in Taiwan led with 107 articles, closely followed by Shanghai Jiao Tong University in Shanghai with 80 articles. Interestingly, 40% of these top 10 institutions are affiliated with Taiwan, while the remaining are primarily from eastern coastal regions in mainland China.

Supplementary Fig. 3 displays the citation analysis of Chinese institutions that have published at least 20 articles. Min-Sheng General Hospital’s papers were the most frequent, with a total of 2975 citations. Collaboration was observed to be stronger within mainland China and Taiwan than inter-regional collaboration.

The top 20 prolific authors, based on publication volume, are listed in Supplementary Table 5. The six most productive authors including Lee WJ (143), Lee YC (79), Huang CK (64), Zhang P (62), Chen SC (60), and Wang Y (59) are affiliated with China. Notably, more than half of the top 20 authors are affiliated with China, while the rest are from Japan, Israel, Iran, and India. Lee WJ has the highest citation count (1914) and h-index (41), while Ser KH holds the highest average number of citations per paper (18.19).

Figure 2a, a bubble heat map of active authors in Asia, shows an upward trend in the authors’ production volume over time, although annual citations fluctuate. Authors including Lee WJ, Wang W, Keidar A, and Lee YC started contributing before 2005, and have maintained their productivity. Conversely, authors such as Zhang P, Pazouki A, Aggarwal S, and Yu HY entered the field later but have made substantial contributions since. Lee WJ, Lee YC, Ser KH, and Chen SC hold the highest citation levels.

Bubble heat map of author contributions in bariatric metabolic surgery research. a Top 20 prolific authors in Asia over time. b Top 20 prolific authors in China over time

Figure 3 depicts the active author network map (based on citations and co-authorship) for Asia. It suggests stronger collaboration within regions than between countries, because in general, authors in the same region are represented by nodes of same color, which indicates they have similar research interests and strong collaborations.

Analysis of active author network in Asia. a Citation analysis depicting the impact of active authors in Asia. b Co-authorship analysis showcasing the collaborative efforts of active authors in Asia

Supplementary Table 6 presents that Lee WJ has received the most citations and h-index in China, while Chen SC has the highest average citation count (15.9). Similar trends as Asia were observed among authors in China (Fig. 2b). The citation and co-authorship analysis (Fig. 4) likewise indicate stronger intra-regional cooperation. The author groups led by Lee WJ and Yu HY are the two most active groups.

Analysis of active author network in China. a Citation analysis reflecting the influence of active authors in China. b Co-authorship analysis illustrating the collaborative network of active authors in China

In a comparison between Mainland China and Taiwan region (Supplementary Table 7), Taiwan initiated obesity surgery 8 years ahead of Mainland China (in 1974), and also commenced laparoscopic BMS 2 years earlier (in 2000). Despite having fewer publications (n = 314) compared with Mainland China (n = 856), Taiwan’s per capita publication count, once adjusted for population (13.33), significantly surpasses that of Mainland China (0.61). In terms of top prolific institutions, Mainland China boasts six, while Taiwan has four. Moreover, Taiwan possesses a larger number of prolific authors within Asia.

The 10 most active journals for BMS research in Asia are listed in Supplementary Table 8. Obesity Surgery (Q2, 3.479) is the leading journal, with 1078 articles, accounting for roughly 30% of total publications. The second most prolific journal is Surgery for Obesity and Related Diseases (Q1, 3.709), making up around 8%. Obesity Surgery also boasts the highest h-index (57). As for the annual publication trend for the top five journals, all have seen consistent growth; however, most experienced a decline after 2020 (Fig. 5a).

Analysis of active journals in bariatric metabolic surgery research for Asia and China. a Yearly article count in the top 5 journals in Asia. b Yearly article count in the top 5 journals in China

The 10 most popular journals for BMS research in China are listed in Supplementary Table 9. The two most sought-after journals in China are identical to those in Asia, which are Obesity Surgery and Surgery for Obesity & Related Diseases, collectively making up 39.72% of total publications. Concurrently, the annual publication trend for the top five journals demonstrates a consistent upward trajectory until 2020 (Fig. 5b).

Supplementary Table 10 lists the top 20 cited articles, with citation numbers ranging from 42 to 112. The most frequently cited article is “Bariatric Surgery: Asia–Pacific Perspective” written by Lee YJ et al. [8], published in Obesity Surgery in 2005, garnering 112 citations. The second most cited article is “Laparoscopic Roux-en-Y Versus Mini-Gastric Bypass for the Treatment of Morbid Obesity: A Prospective Randomized Controlled Clinical Trial” by Lee WJ et al. published in Annals of Surgery in 2005, with 111 citations [19]. The third most cited articles were also authored by Lee WJ, published in Archives of surgery [20].

In China, the top three popular articles are all works of Lee WJ, with respective local citation counts of 81 [8], 72 [19], 61 [20], and 51 [21]. The most popular one, “Bariatric Surgery: Asia–Pacific Perspective,” provides a comprehensive overview of the development of BMS in Asia–Pacific region [8] (Supplementary Table 11).

Table 3 lists the most frequently occurred words in title and abstract in Asia and China. The top three words in the title are “laparoscopic sleeve gastrectomy,” “roux-en-y gastric bypass,” and “type 2 diabetes mellitus,” with 607, 337, and 158 occurrences respectively. Meanwhile, the most frequent used three words in the abstract are “body mass index” (1323), “laparoscopic sleeve gastrectomy” (1217), and “roux-en-y gastric bypass” (829). The most frequent three words in title and abstract of China’s publications mirror those in Asia.

Figure 6 presents a graphical representation of the co-occurrence of authors’ keywords in Asia. Within this network (Fig. 6a), the most frequently occurring keywords are “bariatric surgery,” “obesity,” and “morbid obesity.”

Co-occurrence analysis of author keywords in Asia. a Network visualization depicting the relationship between authors keywords in Asia. b Overlay visualization showcasing the thematic progression of authors’ keywords in Asia

Regarding the network overlay (Fig. 6b), the most recent and popular keywords, represented in yellow, include “laparoscopic sleeve gastrectomy,” “meta-analysis,” and “one anastomosis gastric bypass.” The research topic and frontiers in China align with those in Asia (Fig. 7).

Co-occurrence analysis of author keywords in China. a Network visualization illustrating the interconnectivity of authors’ keywords in China. b Overlay visualization representing the evolution of research themes based on authors’ keywords in China

Figure 8a displays a graph of trending topics in Asia. ‘‘gastric banding” and “type 2 diabetes” are frequently reported in the initial years. However, in recent years, there has been a shift towards more prevalent topics such as “laparoscopic sleeve gastrectomy,” “one anastomosis gastric bypass,” and “nonalcoholic fatty liver disease or NAFLD.”

Trend analysis of research topics in bariatric metabolic surgery. a Bubble heat map depicting the evolution of research topics in Asia over time. b Bubble heat map showcasing the progression of research topics in China over time

Similarly, Fig. 8b illustrates the trending topics in China. In recent years, “nonalcoholic fatty liver disease or NAFLD,” “one anastomosis gastric bypass,” “polycystic ovary syndrome,” and “laparoscopic sleeve gastrectomy” have risen to prominence.