The Socio-Demographic Index is an emerging indicator of social development, the per capita GDP was also used instead LDI in some countries and cities to represent the level of economic[12]. The population health is an important part of social development, and healthy life expectancy can comprehensively reflect the health level. There is a positive strongly correlation between socio-demographic, life expectancy and healthy life expectancy. In the composition index of socio-demographic index, it also showed a strong correlation with healthy life expectancy and life expectancy. Therefore, when considering improving healthy life expectancy, we need to consider the direct factors that affect the health status, but the improvement of indirect factors to improve population health can be taken. This article measured health status from the perspective of social development, not quantitative health, which may have a great significance for taking measures to improve healthy life expectancy.
According to GBD, the socio-demographic index in China in 2017 was 0.71 that belongs to the high-middle SDI level[8], and the level of SDI in China was higher than the global level (0.65). Except for Hong Kong, Macao and Taiwan, the level of SDI in Beijing, Shanghai and Tianjin were all above 0.80, which reached high SDI level. While the level of SDI in Tibet and Guizhou were all below 0.6, which were in the middle-low SDI level. There are great differences in SDI among the provinces in China, so strategies should be made considering with the local condition to improve the health level of each region.
According to National Health Commission of the People’s Republic of China, healthy life expectancy in China in 2016 was 68.7 years old, which was higher than the United States (countries with high SDI level) for the first time. And the latest data showed that life expectancy in China in 2018 was 77 years, an increase of 12.3 years compared with 1990[13]. In 2017, the education rate of 6-year-old and above was about 94.72% (per 1000 population), which was 4.95% higher than that of 2002 (89.77%)[14], and the fertility rate of under 25-year-old decreased with year. The increase of education rate, the increase of per capita income and the decrease of fertility rate increase the composite index SDI, which is closely related to life expectancy and healthy life expectancy that based on the population[15].
The development of life expectancy varied in different province in China. Hainan Province, Chongqing and Fujian Province are with high-middle SDI level. Theoretically, life expectancy should consist with this level, while their life expectancy is relatively low. Similarly, the level of life expectancy in Inner Mongolia and Shanxi province do not match their SDI level. This shows that apart from the geographical situation, there is a huge gap in an indicator within the SDI composition, such as the economic situation. From the geographical east to the west of China, the economic level has gradually declined (shows in Supplementary), and the distribution of SDI can also be seen to gradually develop to a low level.
The development of the socio-demographic index affects healthy life expectancy and life expectancy, and the measurement of healthy life expectancy provides a new direction for evaluating population health. According to the Statistical Information Center of the National Health Commission of the People’s Repbulic of China, in some provinces such as Guizhou Province and Tibet in China, 2016, the result showed that life expectancy in 1-year-old group was higher than the 0-year-old group. This showed that the infant mortality rate in these provinces was relatively high, and the level of SDI in Guizhou Province and Tibet was also at the lower level. Therefore, the fertility rate under the age of 25 should be reduced, and take measures to decrease the infant mortality such as maternal health should be strengthened to improve life expectancy and health life expectancy. In some provinces, the development of life expectancy is inconsistent with SDI level, suggesting that while paying attention to social development, we should pay more attention to adult health care, reduce the exposure of health risk factors, regular physical examination, and decrease the premature death rate of chronic diseases, especially the elderly over 60 years old Health management.
The results of life expectancy and healthy life expectancy calculations show that life expectancy in some regions of China has reached a high SDI level. At the same time, the shortcomings factors affecting life expectancy and healthy life expectancy in some regions are still very prominent. Individualized policies should be implemented for regions and improve the development of socio-demographic index in order to steadily affect the development of healthy life expectancy.