Short answers, pulled from the story.
Dementia is a syndrome characterized by a general decline in cognitive processes that affects the ability to perform everyday activities, including problems with memory, thinking, behavior, and motor control. It is not a normal part of aging; many people aged 90 and above show no signs of dementia at all.
Alzheimer's disease is the most common type, accounting for 60-70% of cases worldwide. Vascular dementia is the second most common, representing at least 20% of cases. Lewy body dementias and frontotemporal dementias are also primary types. Mixed dementia, combining more than one type, was acknowledged in a 2025 NIH study as the most common type overall.
Auguste Deter was a 51-year-old patient who entered a Frankfurt mental hospital on the 25th of November 1901, showing symptoms including paranoia, memory loss, and nighttime wandering. Bavarian psychiatrist Alois Alzheimer agreed to treat her in exchange for her medical records and her brain after death. When she died on the 8th of April 1906, Alzheimer's examination of her brain revealed senile plaques and neurofibrillary tangles, observations he presented at a Tubingen psychiatry conference, leading eventually to the naming of Alzheimer's disease in 1910.
A 2024 global report identified 14 risk factors for dementia, many of which are modifiable. These include lower levels of education, high blood pressure, hearing impairment, smoking, obesity, depression, physical inactivity, diabetes, low social contact, excessive alcohol use, traumatic brain injury, air pollution, untreated visual impairment, and high LDL cholesterol. Researchers estimate that addressing all of these factors could prevent nearly half of dementia cases.
In 2021 there were an estimated 57 million people living with dementia worldwide, with close to 10 million new cases each year, roughly one new case every three seconds. That number is estimated to double every 20 years, potentially exceeding 150 million by 2050. Almost half of all new cases occur in Asia.
No treatment can halt or reverse dementia's progression. Donepezil and rivastigmine, both cholinesterase inhibitors, offer small improvements for Alzheimer's and Parkinson's disease dementia respectively. Memantine provides modest benefit for moderate-to-severe Alzheimer's. EGb 761, a Ginkgo biloba extract approved throughout Europe, is the only treatment showing symptom improvement in both Alzheimer's and vascular dementia. Non-pharmacological approaches including music therapy, animal-assisted therapy, and person-centered care are also used to improve quality of life.