Having a stroke may significantly increase the risk of developing dementia, according to new research presented at the American Stroke Association’s International Stroke Conference 2024. The study found that the risk of dementia was nearly three times higher in the first year after a stroke compared to the general population, and this elevated risk persisted for up to 20 years.
The research, conducted by Dr. Raed Joundi and his team at McMaster University in Canada, analyzed data from over 180,000 stroke survivors in the Canadian province of Ontario. The participants were matched with control groups of individuals without a history of stroke or those who had experienced a heart attack but not a stroke.
The findings revealed that the rate of new cases of dementia was higher than the rate of recurrent stroke over the same time period. The risk of dementia remained elevated even after accounting for other factors such as age, sex, and comorbid conditions. The impact of a stroke on the brain, including areas crucial for cognitive function, may contribute to an increased risk of dementia.
Stroke survivors are uniquely susceptible to dementia, and we found that this risk can be up to three times higher in the first year following a stroke. Although the risk decreases over time, it remains elevated in the long-term, explained Dr. Joundi.
With approximately 795,000 people experiencing a new or recurrent stroke each year, the implications of this research are significant. The American Heart Association’s Heart Disease and Stroke Statistics 2024 Update states that 610,000 of these cases are first attacks, while 185,000 are recurrent. Furthermore, there are currently an estimated 7 million adults with dementia among those aged 65 and above, and this number is projected to nearly double by 2060.
The study highlights the urgent need for monitoring stroke survivors for cognitive decline and implementing appropriate treatments to address vascular risk factors and prevent recurrent stroke. Lifestyle changes can also play a role in reducing the risk of dementia, such as smoking cessation and increased physical activity.
While the study provides valuable insights into the connection between stroke and dementia, more research is needed to understand why some stroke survivors develop dementia while others do not. The researchers acknowledge that their study had limitations, as they were unable to perform cognitive assessments or neuroimaging on the participants. However, the reliability of the dementia diagnosis was confirmed through validation against medical charts.
In light of these findings, the American Heart Association has recommended post-stroke screenings and comprehensive interdisciplinary care to support stroke survivors with cognitive impairment. By addressing the cognitive effects of stroke, healthcare professionals can better assist individuals in their recovery and long-term brain health.
Overall, this study serves as a wake-up call to healthcare providers and policymakers, emphasizing the importance of prioritizing dementia prevention and management among stroke survivors. With further research, interventions and strategies can be developed to mitigate the long-term cognitive consequences of stroke and improve the quality of life for millions of individuals worldwide who are affected by both stroke and dementia.
