About 7.4 million Americans age 65 and older are living with Alzheimer’s disease, and roughly 57 million people worldwide have some form of dementia, with Alzheimer’s accounting for the majority of those cases. These numbers are climbing fast as populations age, and a significant share of cases go undiagnosed entirely.
Alzheimer’s in the United States
Of the 7.4 million Americans age 65 and older with Alzheimer’s, nearly two-thirds are women. That breaks down to about 4.4 million women and 3 million men. The reasons women are disproportionately affected aren’t fully settled, but the simplest factor is longevity: women live longer on average, and age is the single biggest risk factor for the disease.
The risk rises sharply with each decade of life. CDC data from 2022 shows that 1.7% of adults ages 65 to 74 have a dementia diagnosis. That jumps to 5.7% for people 75 to 84 and reaches 13.1% for those 85 and older. In other words, roughly 1 in 8 people over 85 has been diagnosed.
Alzheimer’s is the sixth leading cause of death in the United States, responsible for over 116,000 deaths per year.
Global Numbers
The World Health Organization estimated that 57 million people were living with dementia worldwide in 2021. More than 60% of them live in low- and middle-income countries, where access to diagnosis and care is limited. Alzheimer’s disease is the most common type of dementia globally, typically representing 60% to 70% of all cases.
Racial and Ethnic Disparities
Alzheimer’s does not affect all communities equally. In the United States, Black Americans are roughly 1.5 to 2 times as likely as white Americans to develop Alzheimer’s and related dementias. Higher rates of hypertension and diabetes in Black communities, both of which are risk factors for dementia, contribute to this gap. Hispanic Americans also face elevated risk compared to non-Hispanic white Americans.
Paradoxically, Black participants in research studies are 35% less likely to receive an Alzheimer’s diagnosis than white participants, even when they show higher rates of cognitive impairment on tests of processing speed, executive function, and language. This suggests that standard diagnostic tools and clinical settings may be missing cases in Black patients, widening the gap between who has the disease and who gets identified.
How Many Cases Go Undiagnosed
The official numbers almost certainly undercount the true scope. A community-based study found that underdiagnosis is widespread, and it hits some groups harder than others. Among Black participants, about 86% of dementia cases were undiagnosed. Among Hispanic participants, that figure was nearly 91%, compared to 65% among non-Hispanic white participants.
Several factors predict whether someone slips through the cracks. People without a regular doctor had an underdiagnosis rate of 98%, compared to 78% for those with physician access. Non-English speakers were underdiagnosed at nearly 98% as well. Each additional year of education a person had was associated with a 2.5% lower chance of being missed. These patterns suggest that the true number of Americans living with Alzheimer’s is substantially higher than the 7.4 million in official estimates.
Projected Growth by 2050
The Alzheimer’s Association projects that the number of Americans age 65 and older with Alzheimer’s will reach nearly 13 million by 2050, roughly a 75% increase from current levels. This growth is driven almost entirely by demographics. The baby boom generation is moving into the highest-risk age brackets, and people are living longer. Without a treatment that meaningfully slows or prevents the disease, the caseload will continue to swell as the population ages.
The Financial Cost
Alzheimer’s is one of the most expensive conditions in the country to manage. Research led by the USC Schaeffer Center estimates that the total economic burden of Alzheimer’s and related dementias will reach $781 billion in 2025. That figure includes direct medical and long-term care costs of $232 billion, of which $52 billion comes out of pocket from patients and their families.
Public programs shoulder the bulk of the cost. Medicare pays an estimated $106 billion per year for dementia-related care, and Medicaid covers another $58 billion, largely for nursing home stays. Together, those two programs account for more than two-thirds of direct care spending. The remaining economic burden comes from the unpaid labor of family caregivers, whose time and lost wages add hundreds of billions more to the total.