In the later stages of dementia, symptoms become very severe. Patients experience significant impairment in memory function, forgetting not only recent events but also events from the past. Additionally, patients show obvious impairments in visuospatial abilities, having trouble locating the bathroom in their own home, and often getting lost when they go out. There is also a noticeable change in behavior, with patients exhibiting aggression, cursing, and inappropriate actions like urinating or defecating in random places. Some patients may experience recurrent visual and auditory hallucinations. As the disease progresses, elderly patients may eventually become bedridden for life, not interacting with anyone, remaining silent, and refusing to eat. They ultimately may die from complications such as lung infections, urinary tract infections, malnutrition, and bedsores. Therefore, the symptoms of dementia in its later stages are quite severe, with cognitive impairments, abnormal mental and behavioral symptoms, and various infections all posing serious threats to the health of the elderly.