What is the fine-grained topic of the following text: At the end of the 10-year follow-up period, the researchers noted 97 cases (3%) of stroke, 82 of which were ischemic (caused by blockage of blood vessels), and 81 (5%) cases of dementia, 63 of which were diagnosed as Alzheimer’s disease. Only return the topic.
Long-term research on stroke, dementia, and Alzheimer's disease incidence