Prevalence, trends and risk factors for the diabetes epidemic in China: A systematic review and meta-analysis

Abstract

Aims

To describe the prevalence and trends of diabetes and to quantitatively assess its risk factors in mainland China.

Methods

Thirty-one epidemiological studies were identified by a systematic search of four databases. Prevalence estimates were mapped and summarized by meta-analysis in each region of China. The pooled ORs and 95% CIs of risk factors for diabetes were also calculated.

Results

There was a large geographical imbalance with regard to the prevalence of diabetes. Region-pooled prevalence was highest in the eastern region (8.0%, 95% CI: 6.1–10.0%) and lowest in the western region (4.6%, 95% CI: 3.3–6.0%), which was consistent with regional levels of economic development. The overall prevalence of diabetes has been increasing since 1980. Traditional risk factors such as age, family history of diabetes, obesity, hypertension and elevated triglycerides were found to be associated with diabetes. In addition, urban residence and being from ethnic minorities were also significantly associated.

Conclusion

Based on the meta-analyses, we found that the prevalence of diabetes is different in different parts of China but it has been increasing sharply during the last three decades. Some risk factors were quantitatively derived in the study, which are free from the diversity of a single sample.

Introduction

The prevalence of diabetes has been steadily rising in recent years and it has reached epidemic proportions worldwide along with the acceleration of globalization and urbanization [1], [2]. As the largest developing country in the world, China has experienced a sharp increase in the prevalence of diabetes and pre-diabetes in the past years. A recent nationwide diabetes epidemiological study indicated that the prevalence of diabetes has reached 9.7% in mainland China, translating into 92.4 million adults with diabetes [3]. China has become the top country with the largest number of people with diabetes in the world [4].

Recent dramatic urbanization and economic development in China has resulted in a nutrition transition and changes in lifestyle [5], [6], [7]. However, the prevalence of diabetes varies in different regions due to a considerable difference in socioeconomic development during the transitional process.

China currently has a population of 1.34 billion [8]. Therefore the potential effect of diabetes on the global economy and society are very large. The Chinese government and researchers have conducted a number of population-based epidemiological studies on diabetes both nationwide and at regional levels during the last decade. Synthesis of these results can provide a better understanding of the situation and how it can be addressed. Although there have been previous comprehensive reviews focusing on various aspects of diabetes in China [9], [10], [11], [12], [13], [14], they are mostly narrative and none performed a meta-analysis which can provide more precise and reliable effect estimates and the previous reviews did not give statistically combined results of comparable studies. Further mapping and quantitating the situation is of paramount importance. In this study, we conducted a systematic review and meta-analyses aiming to describe the prevalence and trends of diabetes as well as quantitatively assessing its risk factors in China.