To understand the disease burden, age, period, and cohort impact of diarrhea caused by unsafe water in China from 1990 to 2021.

The mortality and disability-adjusted life year (DALY) rates of diarrhea caused by unsafe water in China from 1990 to 2021 were collected and organized through the 2021 Global Burden of Disease Study (GBD 2021).Joinpoint regression was used to analyze temporal trends and calculate the average annual percentage change (AAPC). Using Stata MP 17 (64-bit) software, a Bayesian age-period-cohort model was used to analyze the impact of age, period, and cohort on diarrhea caused by unsafe water in China from 1990 to 2021.

The mortality rate, standardized mortality rate, DALY rate, and standardized DALY rate of diarrhea caused by unsafe water in China showed a decreasing trend year by year from 1990 to 2021 (AAPC=-10.69%, -10.92%, -11.48%, -10.74%, P<0.001). Similar decreasing trends were observed in both males and females. The age effect in the APC model indicated that people under 5 years old and those over 65 years old had a higher risk of mortality from diarrhea caused by unsafe water (RR values were all>1). The period effect showed that the mortality and DALY risk of diarrhea caused by unsafe water decreased from 1990 to 2021. The cohort effect showed that the earlier the population was born, the higher the risk of death and DALY from diarrhea caused by unsafe water.

From 1990 to 2021, the mortality and DALY risk of diarrhea caused by unsafe water in China have decreased. However, children and the elderly still have a high risk of diarrhea caused by unsafe water. It is necessary to actively provide safe drinking water, reduce the spread and impact of diarrhea caused by unsafe water sources, and protect public health.