Life Expectancy Inequality Between Regions of China 2004-2019: Contribution of Age- and Cause-specific Mortality

Background: China is currently experiencing a period of rapid epidemiological transition, characterized by significant shifts in disease patterns and health outcomes. The epidemiological transition theory suggests that the inequality in life expectancy between regions within China can vary significantly. Therefore, the aim of this study is to investigate the dynamic trends in the LE gap between regions in China from 2004 to 2019, with a specific focus on analyzing the LE disparities in age-specific and cause-specific improvements in mortality across different regions. Methods The study employs the log-quadratic method to estimate the LE gap between regions in China. Using the Arriage LE decomposition method, we analyze the age-specific and cause-specific components of LE changes during two distinct periods: 2004–2011 and 2012–2019. By integrating the theory of epidemiological transition with empirical trends in LE changes, we examine the alterations in the LE gap among different regions. Results Between 2004 and 2019, the LE gap between regions in China exhibited a pattern characterized by an initial sharp decrease followed by a subsequent gradual increase. During this period, the reduction in the LE gap can predominantly be attributed to differences in the contribution of childhood infectious diseases and maternal and child diseases, while the expansion of the gap is primarily driven by variations in the impact of chronic diseases among the elderly population, particularly cardiovascular disease and malignant neoplasms. Notably, the negative contribution of diseases such as diabetes also contributes to the observed widening gap. The decline in LE gains in the western region is mainly attributable to a decrease in all-age mortality improvement, with this deceleration deviating from the observed empirical trend in LE changes. The higher-than-expected increase in LE in the eastern region is mainly associated with improvements in chronic diseases among the elderly population. Conclusion Following a marked decline, the LE gap between regions in China has experienced a slight widening. The principal factor contributing to this widening gap is the inadequate improvement in all-age mortality in the western region. Future efforts to reduce the LE gap between regions should prioritize improvements in all-age mortality in the western region, particularly in major chronic diseases and diseases such as diabetes that adversely impact mortality improvement. The implementation of effective health intervention policies, such as universal health coverage or equalization of primary health services in the western region, will play a crucial role in addressing these disparities.