Objective To analyze mortality of major chronic diseases in 20 national cause-of-death surveillance areas in Inner Mongolia autonomous region in 2021 and its trend from 2014 to 2021 in Inner Mongolia, understand the disease burden of major chronic diseases and provide evidence for chronic disease prevention and control.

Methods Death Information Registration Management system was used to collect the mortality data in national cause-of-death surveillance areas in Inner Mongolia during 2014–2021, and the International Classification of Diseases (10^th edition) was used to classify and code the underlying causes of death in local residents. Software SAS 9.4 was used to clean the original data; Data such as crude mortality rate, standardized mortality rate and probability of premature death were collated and calculated by Excel 2007 and software SPSS 23.0, and the data from the sixth National Census in 2010 were used for standardization. Joinpoint software was used to calculate average annual percentage change (AAPC), and trend analysis was performed. The rates were compared by χ² test.

Results In 2021, the crude mortality rate of four major chronic diseases was 570.14/100 000 in the national cause-of-death surveillance area in Inner Mongolia, the mortality rate was 469.82/100 000 in women and 662.43/100 000 in men, and the rate was higher in men than in women (χ²=798.70, P<0.05). From 2014 to 2021, the crude mortality rate ranged from 590.28/100 000 to 663.04/100 000 in residents in the national cause-of-death surveillance area in Inner Mongolia r, showing an increasing trend (AAPC=1.3%, t=5.5, P<0.05) and the standardized mortality rate ranged from 641.38/100 000 to 488.70/100 000, showing a downward trend (AAPC=−3.5%, t=−8.8, P<0.05). From 2014 to 2021, the crude mortality rate of four major chronic diseases ranged from 499.61/100 000 to 570.14/100 000, in the national cause-of-death surveillance area in Inner Mongolia, showing an increasing trend (AAPC=1.6%, t=4.8, P<0.05) and the standardized mortality rate ranged from 601.59/100 000 to 414.63/100 000, showing a downward trend (AAPC=−4.2%, t=−4.5, P<0.05). From 2014 to 2021, the probability of premature death of four major chronic diseases ranged from 20.76% to 14.59% in the national cause-of-death surveillance areas in Inner Mongolia, showing a downward trend (AAPC=−4.7%, t=−6.6, P<0.05).

Conclusion From 2014 to 2021, the crude mortality rate showed an increasing trend in residents in national cause-of-death surveillance areas in Inner Mongolia. Cardiovascular and cerebrovascular diseases, malignant tumors and chronic respiratory diseases were the main causes of death in residents in Inner Mongolia. In the future, the prevention and treatment of the four major chronic diseases should be strengthened, especially in men. Meanwhile, it is necessary to pay attention to the elderly.