Alzheimer’s disease is remarkably common. An estimated 7.2 million Americans age 65 and older are living with Alzheimer’s dementia in 2025, which works out to about 1 in 9 people in that age group. It is a top 10 leading cause of death in the United States and the single most common cause of dementia worldwide.
Prevalence by Age Group
The risk of Alzheimer’s rises steeply with age. Among people 65 to 74, about 5% have the disease. That number jumps to 13.2% for people 75 to 84. And among those 85 and older, roughly one in three (33.4%) is living with Alzheimer’s dementia. This sharp escalation is why the disease becomes so much more visible as populations age.
Alzheimer’s is not exclusively a disease of older adults, though. An estimated 200,000 Americans under age 65 have what’s called younger-onset Alzheimer’s, which translates to about 110 out of every 100,000 adults between ages 30 and 64. These cases are far less common but tend to be diagnosed later because neither patients nor doctors expect dementia symptoms at that age.
Who Is Affected Most
About two-thirds of Americans diagnosed with Alzheimer’s are women. Part of this is straightforward: women live longer on average, and longer life means more years in the highest-risk age brackets. Whether women also face a higher biological risk, independent of lifespan, is still debated. The difference in raw numbers, though, is substantial.
Race and ethnicity also play a role. Older Black adults are about twice as likely as older white adults to develop Alzheimer’s. Hispanic adults are roughly one and a half times as likely. These disparities reflect a mix of factors, including higher rates of cardiovascular disease, less access to early diagnosis and treatment, and socioeconomic conditions that influence brain health over a lifetime.
Global Scale
The World Health Organization estimated that 57 million people worldwide were living with dementia in 2021, with Alzheimer’s accounting for the majority of those cases. Over 60% of people with dementia live in low- and middle-income countries, where access to diagnosis and care is limited. As populations in these regions age, the global burden is expected to grow considerably.
How the Numbers Are Changing
The total number of Americans with Alzheimer’s has climbed steadily, driven primarily by the aging of the baby boomer generation. Between 2000 and 2021, the number of deaths attributed to Alzheimer’s on U.S. death certificates more than doubled, increasing 141%. In 2022, it was the 7th leading cause of death among all U.S. adults and the 6th leading cause among those 65 and older.
That growth is not slowing down. As more Americans enter their mid-70s and 80s, the population living with the disease will continue to expand, even if the per-person risk at each age stays roughly the same. The Alzheimer’s Association projects significant increases in coming decades simply because of demographic shifts.
The Financial Weight
Alzheimer’s and other dementias are among the most expensive conditions to manage. Total medical and long-term care costs reached $232 billion in 2025. Medicare covers about $106 billion of that. Medicaid accounts for $58 billion, largely for nursing home care. Families themselves pay $52 billion out of pocket, with the remainder covered by private insurance and other payers.
These figures don’t capture the unpaid caregiving that millions of family members provide. Most people with Alzheimer’s eventually need help with daily activities like bathing, dressing, and eating, and that care often falls on spouses and adult children who reduce their own work hours or leave jobs entirely. The true economic toll, when you include lost wages and caregiver health effects, is significantly higher than the direct medical costs alone.