Using Real-world data to Estimate the Changing Trends in the Prevalence and Incidence of type 2 Diabetes Mellitus in Xiamen of China,2014-2019

Background: The prevalence of diabetes is increasing worldwide. Our study aimed to estimate the changing trends in the prevalence and incidence of diagnosed type 2 diabetes mellitus (T2DM) among Xiamen residents and the oating population using real-world data. Method: We used real-world data from the System of Xiamen Citizens Health Information from 2014 to 2019 to estimate the changing trends in prevalence and incidence of diagnosed T2DM. The systems included the diagnosis of diabetes and the prescription of hypoglycemic drugs. Prevalent cases of T2DM were individuals who diagnosed T2DM and/or using hypoglycemic drugs. Incident cases were individuals with diagnosed T2DM and/or using hypoglycemic drugs in 2014 who had not diagnosed and/or no used one in the past. Results: In 2014 and 2019, the prevalence of T2DM in Xiamen was 4.04% and 4.84%, respectively. In 2014 and 2019, the incidence of T2DM in Xiamen was 1.41% and 1.50%, respectively. There was an increase signicant in the total of the prevalence and incidence of T2DM in Xiamen (0.80% (95% CI 0.76%-0.83%, P <0.001; 0.09% (95% CI 0.07-0.11), P<0.001, respectively). The prevalence and incidence of T2DM in people aged 18-39 increased signicantly, while the prevalence and incidence of T2DM in people aged 40-69 reduced signicantly. Conclusions: We found that there was an increasingly signicant in the total of the prevalence and incidence of T2DM in Xiamen from 2014 to 2019. The prevalence and incidence of T2DM in Xiamen were signicantly increased and showed a trend of younger age.


Background
Diabetes is a series of chronic and progressive diseases caused by genetic and environmental factors that can lead to a chronic damage, dysfunction, and even failure of multiple organs. Owing to its high prevalence and related disability and mortality, thus diabetes has become a vital health problem worldwide [1,2]. With the rapid development of the economy, the improvement of people's living standards, and the change of lifestyle in China in the past three decades, diabetes has become a chronic disease that seriously endangers people's health. Studies in recent years have shown that the global prevalence of diabetes is increasing signi cantly and varies by age, geography, regional economic disparities, ethnicity, etc. [3].
Over the past 40 years, the prevalence of diabetes in China has increased from less than 1-12.8% in 2018, and the prevalence of prediabetes is 35.2%, making it the country with the largest number of diabetes cases in the world, with type 2 diabetes mellitus (T2DM) accounting for more than 90% of patients [1,4]. The total prevalence of diabetes in China from 2007 to 2008 was 9.7%, among which the prevalence of diagnosed diabetes was 4.1% in males and 3.5% in females [5]. The overall prevalence of diabetes in 2010 in China was 11.6%, with the prevalence of diagnosed diabetes at 3.5%, in males and females at 3.6% and 3.4%, respectively [3]. The overall prevalence of diabetes in 2013 in China was 10.9%, of which the prevalence of diagnosed diabetes was 4.0% (3.9% in males, 4.1% in males) [4].
Studies have revealed that the prevalence and the number of adults with diabetes have increased more in low -and middle-income countries than in middle -and high-income countries [6]. Rapid economic development and urbanization have resulted in an increasing burden of diabetes in many parts of the world [7]. As an important central city on the southeast coast of China, Xiamen's urbanization has reached up to 89.2%. In 2019, Xiamen's Gross Domestic Product (GDP) was close to 857.1 billion dollars, and the per capita GDP exceeded 20,000 dollars, which have reached the standards of developed economies. The data from the Xiamen Government Finance Bureau have shown that diabetesrelated costs in Xiamen exceeded 43 million dollars in 2019, accounting for approximately 14.2% of the total annual cost of medical. The cost of diabetes care is statistically at least 3.2 times higher than the per capita medical expenditure and up to 9.4 times higher in the case of diabetes-related complications, so the impact on individuals and society at large if the development of diabetes is not controlled promptly is incalculable [8,9]. Therefore, exploring the prevalence and incidence of diabetes in Xiamen is of great signi cance to the management and China implemented healthcare reforms of diabetes in coastal areas of China. However, there are few data on the prevalence and incidence of diabetes in Xiamen. In this study, we used real-world data from the System of Xiamen Citizen Health Information to estimate the changing trends in the prevalence and incidence of diagnosed T2DM among Xiamen residents and the oating population.

Health system
The data of this study comes from the System of Xiamen Citizens Health Information, which is comprehensive information management and service platform jointly built by the Xiamen Municipal Health Bureau and China Mobile.
All patients have a unique health insurance number and include information from all medical records of community hospitals, secondary and tertiary hospitals, and pharmacies, as well as diagnosis and medication information related to diabetes.

Data
In this study, the real-world data from the System of Xiamen Citizens Health Information included the diagnosis of

The change in the incidence of T2DM in Xiamen
There was an increase in the total of the incidence of T2DM from 2014 to 2019, the difference in the increase was 0.09%

Discussion
In this study, we found that there was an increasingly signi cant in the total of the prevalence and incidence of T2DM in Xiamen from 2014 to 2019. The prevalence and incidence of T2DM in people aged 18-29 years and 30-39 years increased signi cantly from 2014 to 2019, while the prevalence and incidence of T2DM in people aged 40-69 years reduced signi cantly from 2014 to 2019, indicating that the prevalence and incidence of T2DM in Xiamen were signi cantly increased and showed a trend of younger age.
The result of our study was consistent with the concept that diabetes tends to be greater among the young in Asia [10].
The results showed that one in ve adult patients was diagnosed with T2DM before age 40 and that younger patients with T2DM had poor awareness of disease management, suggesting that more young people will suffer from T2DM in the future [10]. have undergone major changes, the proportion of cereal intake has decreased, the proportion of meat and fat has increased, fat intake has increased, physical exercise have decreased, all of these can promote the occurrence and development of overweight, obesity and diabetes [11,12]. This shows that the situation of prevention and treatment of diabetes in Xiamen is very serious.
This study found that the prevalence of T2DM in Xiamen was 4.84% in 2019. The prevalence among men and women , of which the prevalence of diagnosed diabetes was 6.0% (6.4% in men, 5.6% in women) (16). According to the study, the prevalence of diagnosed diabetes in urban and southern China was 7.1% and 5.8% respectively, both higher than the prevalence of T2DM in Xiamen in our study.
The lower prevalence and incidence of T2DM in Xiamen compared to the studies mentioned above may be attributed to many factors. There is considerable evidence that Western diets characterized by meat are signi cantly associated with T2DM, while Mediterranean diets characterized by plants are associated with a low risk of diabetes [13,14]. A metaanalysis has concluded that the intake of red meat and processed meat is positively associated with the risk of T2DM, while the intake of aquatic products has no signi cant correlation with the risk of T2DM [15]. Our study showed that the prevalence of T2DM in Xiamen in 2019 was lower than the prevalence of diagnosed diabetes in China in 2018 (4.84% vs 6.0%), which may be related to the fact that Xiamen is located in the coastal area of China, where the seafood is abundant and diverse, and the per capita daily intake of aquatic products of Xiamen residents is higher than the average level of all over the world. Xiamen's urbanization process is advancing by leaps and bounds. As one of the most advanced cities in China, Xiamen's green coverage is up to 45%. The ecological civilization index ranks rst and reaches the world's advanced level. Not only that, but Xiamen citizens also admire national sport, especially badminton and marathon. The Xiamen Health Trail was also completed in 2019, aiming to provide more convenient places for people to play sport and improve their physical quality. Xiamen provides free medical examination services for the elderly every year. And the average life expectancy of Xiamen residents reached 80.45 years in 2017.
The prevalence of diabetes among the oating population is lower than that of the general population, but considering the growth rate of the oating population and the poor disease management awareness among the oating population, the potential threat posed by diabetes among this group cannot be ignored. In 2017, a study calculated that the prevalence of diabetes among the mobile population in China was 5.1% (95% CI 4.9-5.3), and the prevalence was higher among women than men [16]. Xiamen is a developed coastal economic region with a large number of migrant workers and a large migrant population, but there are few reports on the prevalence of diabetes among the oating population.
This study explored this issue for the rst time and found that in 2019, the number of oating population in Xiamen was 840,443, and the prevalence of T2DM was 0.94%(1.42% in women, 0.58% in men). The age of 18-29 years people was the most oating population, with a prevalence of 0.45%. Those over 70 years old have the highest T2DM prevalence, which was 2.64%. It can be seen from the above data that the prevalence of diabetes among the oating population in Xiamen is far lower than the national average level, which may be attributed to the following reasons: 1) Most of the oating population in Xiamen are working people with good physical tness and great exercise intensity, and there are fewer obese or overweight people, thus reducing the risk of diabetes. 2) Most of the oating population who come to Xiamen does not have medical insurance in Xiamen, so it may not be possible to record diagnosed diabetes cases into the system of Xiamen citizen health information. The government and the hospital should offer T2DM knowledge lectures or online classes for the oating population in Xiamen, to improve their self-management awareness of T2DM, and effectively control the epidemic trend of T2DM in the oating population.
The strength of our study included a large sample of a population-based longitudinal study to direct comparison of T2DM prevalence and incidence from 2014 to 2019 in population in Xiamen. The prevalence and incidence of T2DM in this study were evaluated based on real and reliable data. There were also several limitations to our study. First, the study is limited by the lack of information on patients with undiagnosed diabetes. Second, there may be some patients with T2DM who do not receive medication and be only controlled by diet. Finally, we only analyzed T2DM and had no information on other types of diabetes including type 1 diabetes.

Conclusion
In summary, Our study used real-world data from the system of Xiamen citizen health information to estimate the trend in the prevalence and incidence of T2DM. We found that there was an increasingly signi cant in the total of the prevalence and incidence of T2DM in Xiamen from 2014 to 2019. The prevalence and incidence of T2DM in people aged 18-39 years increased signi cantly, while that in people aged 40-69 years reduced signi cantly from 2014 to 2019, indicating that the prevalence and incidence of T2DM in Xiamen were signi cantly increased and showed a trend of younger age. This approach affords to monitor epidemic trends in real-time, thus providing a basis for health policies and health service plans.

Declarations
Ethics approval and consent to participate The study was approved by the research Ethics Committee at the First A liated Hospital of Xiamen University. The system of Xiamen citizen health information is a collaborative platform for medical institutions, with access to raw data under the authority of the Xiamen Municipal Health Commission.

Availability of data and materials
Data sharing is not applicable to this article, as no datasets were generated or analyzed during the current study.

Funding
This work was supported by the National Natural Science Foundation of China (No. 81870606).