Age-Period-Cohort Analysis of Type-Specific Stroke Morbidity and Mortality in China

Stroke has become the leading cause of death in China. This study aimed to assess the age-period-cohort (APC) effects on the long-term trends of type-specific stroke morbidity and mortality in China between 1993 and 2017.

The data were obtained from the Global Burden of Disease 2017 (GBD 2017) and were analyzed with the age-period-cohort framework. The net drifts of mortality were below 0 (hemorrhagic stroke [HS]: males: -1.620%, females: -3.531%; ischemic stroke [IS]: males: -1.041%, females: -3.002%), and the local drift values were below 0 in all age groups and for both genders. The net drifts of HS incidence were below 0 (males: -1.412%, females: -2.688%), while those of IS were above 0 (males: 1.425%, females: 1.117%). Period effect of mortality showed similar monotonic downward patterns for both genders, with a faster decrease for females than for males. Period effect of incidence showed a declined trend of incidence for HS, but an elevated trend for IS in both genders. After controlling for age and period effects, cohort effects on incidence found a monotonic decline trend for HS, while for IS, an elevated trend was found at first to peak during the 1950-1970 s, then declined steadily afterwards. Cohort effects on mortality showed a monotonic declined trend.

By using Age-Period-Cohort (APC) analysis, a disparity between HS and IS was identified. Different prevention and control strategies should be used depending on the subtypes of stroke.