Trends in incidence and mortality of ischemic and hemorrhagic stroke in China, 2015―2019

Objective To present the epidemiological characteristics of incidence and mortality of ischemic and hemorrhagic stroke in national cardiovascular disease surveillance areas from 2015 to 2019.Methods Data of stroke incidence and mortality from 2015 to 2019 were collected from the China Registry of Cardiovascular Events (China RACE)，which was established in 2014, covering 100 counties (cities, districts) in 31 provinces in China. The ratio of ischemic to hemorrhagic stroke incidence rates were calculated, and the subtype-specific mortality to incidence ratio (M/I) were provided and compared between subtypes. The Joinpoint model was used to analyze the annual trend incidence rates (annual percentage changes, APC). The age-standardized incidence rate (ASIR) was calculated using the Seventh National Census data as the standard population.Results From 2015 to 2019, the crude incidence rate (CIR) of ischemic stroke increased by 15.61% (APC=3.54%, Ptrend < 0.01), resulting in a relative ratio of incidence rate reaching 4.35:1 against hemorrhagic stroke. And the crude incidence rate of ischemic stroke rural areas increased 24.05% (APC=5.69%, Ptrend < 0.01), accompanied with more rapid increasing presented in male (APC=4.00%, Ptrend < 0.01) than in female (APC=3.01%, Ptrend < 0.01). Meanwhile, the overall ASIR of hemorrhagic stroke decreased by 20.99% (APC= -5.59%, Ptrend < 0.05) , with 29.38% reduction (APC=-8.10%, Ptrend < 0.01) counted in rural areas, as well as more slow decline showed in males (APC=-5.07%, Ptrend < 0.05) than in females (APC= -6.33%, Ptrend < 0.05). Moreover, the residents aged 45-49 years presented an increasing trend in the CIR of ischemic stroke (Ptrend < 0.05) from 2015 to 2019, paralleled with a decreasing trend in hemorrhagic stroke (Ptrend < 0.05) among those aged 70-74, 80-84 and ≥85 years. Except for those < 35 years old, the incidence ratio of ischemic to hemorrhagic stroke increased with age in 2019. From 2015 to 2019, the overall relative ratio of M/I (RR) for ischemic to hemorrhagic stroke was 4.2:1, which was lower in urban than in rural areas (3.8 vs 4.3). The largest gap between urban and rural areas was detected in the 55-59 age group (6.8 vs 9.3).Conclusions Ischemic and hemorrhagic stroke incidence in the monitoring areas was remarkably severe, and the geographic diversity and age-specific divergence became more complicated by stroke subtypes. More precise and comprehensive policies are urgently required in China.