MONDAY, Dec. 9, 2024 (HealthDay News) -- Almost one in five stroke survivors are diagnosed with dementia, with increased risk lasting for 20 years after stroke, according to a study published online Dec. 4 in _Neurology_.
Raed A. Joundi, M.D., from the McMaster University & Population Health Research Institute in Hamilton, Ontario, Canada, and colleagues conducted a population-wide analysis of people in Ontario between 2002 and 2022 to explore dementia risk after stroke. Adults hospitalized for ischemic stroke, intracerebral hemorrhage, or acute myocardial infarction (AMI) were identified; those with stroke (175,980 survivors) were matched in a 1:1 ratio to a reference population without stroke (174,817) and separately to those with AMI (151,673).
The researchers found that 18.7 percent of those with stroke and 12.5 percent in the reference population were diagnosed with dementia during a mean follow-up of 5.6 years. Over total follow-up time, the rate of dementia per 100 person-years was higher after acute stroke compared with the reference population (3.34 versus 1.89) and the AMI cohort (3.19 versus 1.75). Compared with the reference population and the AMI cohort, the hazard ratio of dementia was higher in those with stroke (1.76 and 1.82, respectively). Hazard ratios varied over time, with a >2.5-fold increase in dementia risk within one year, 1.5-fold increase at five years, and 1.3-fold increase at 20 years after stroke. A threefold increased dementia risk was seen in association with recurrent stroke.
"The risk was highest early after stroke but remained elevated 20 years after, highlighting the need for developing new interventions for dementia prevention in the acute and chronic phases of stroke," the authors write.
[Abstract/Full Text (subscription or payment may be required)](https://n.neurology.org/lookup/doi/10.1212/WNL.0000000000210131)
[Editorial (subscription or payment may be required)](https://n.neurology.org/lookup/doi/10.1212/WNL.0000000000210230)