Global, Regional and National Burdens of Stroke and Its Subtypes: Unraveling the Correlations with the Global Aging Trend

The global ageing trend is accelerating, leading to an increase in chronic diseases and posing a significant health challenge. Stroke, characterised by high rates of disability and mortality, is emerging as one of the most critical public health issues. The aim of this study was to examine current trends in global ageing and, under this condition, to assess the burden of stroke, with a focus on the elderly population at high risk of stroke. The data utilised in this study was obtained from the Global Burden of Diseases Study 2021, which estimated the burden of stroke and its subtypes, including ischaemic stroke, intracerebral hemorrhage, and subarachnoid haemorrhage focusing on incidence, mortality, and disability-adjusted life year (DALY) rates. To investigate the correlation between ageing and stroke burden as well as its temporal trends, Pearson correlation analysis, decomposition analysis, and estimated annual percentage change were conducted. Globally, the proportion of countries entering ageing society has almost doubled, rising from 30.4% in 1990 to 52.5% in 2021. The Pearson correlation coefficient showed a significant positive association between stroke burden and the degree of ageing, particularly for incidence rate (R=0.64, P<2.2e-16) and mortality rate (R=0.44, P=5.3e-16). In addition, the global increase in stroke DALYs from 1990 to 2021 was largely attributable to population ageing, which accounted for 99.9% of this increase. In more than half of the countries, the burden of stroke was mainly concentrated in the elderly population aged 65 years and above, especially for ischaemic stroke, while the younger population predominantly borne the burden of haemorrhagic stroke. Despite the observed reductions in the incidence, mortality and DALY rates of stroke and its subtypes, the overall absolute numbers were still on an upward trajectory. Significantly, the majority of the burden of stroke was borne by the elderly. Therefore, the promotion of healthy ageing worldwide is critical and requires the rapid and effective development and implementation of appropriate public health policies and preventive management strategies to reduce the expected increase in the burden of stroke in the near future, particularly in the face of the challenges of global ageing wave.