The areas of the US where Alzheimer’s is most rife have been revealed — with seniors on the East Coast and South East most likely to be struck down by the memory-robbing disorder.
The new report by the Alzheimer’s Association International Conference (AAIC) offers the most granular look at the prevalence of the condition, providing estimates of the rates at the county level for the first time.
It shows that while overall, 6.7 million Americans over 65 have the disease — roughly one in ten — in some counties, the share is as high as one in six.
For example, in the three top places — Miami, Baltimore and the Bronx — an estimated one in six have the condition.
Rounding out the top five counties for Alzheimer’s disease sufferers were Prince George’s County in Maryland (16.1 percent) and Hinds County, Mississippi (15.5 percent).
It comes as results from trials of the drug donanemab showed it can slow early Alzheimer’s by up to 60 percent in a breakthrough hailed as the ‘turning point’ in the fight against the disease.
Hover over your county to see the rate of Alzheimer’s in over 65s
Researchers at the Alzheimer’s Association used the latest data available from 2020 from thousands of over-65s to map the proportion of seniors with the disease in all 3,142 counties in the United States.
The Association said the report, presented this week at their conference in Amsterdam, aimed to inform authorities where there was the highest need for Alzheimer’s resources. Experts said it could also prompt people to get checked for the disease, as many are not diagnosed until later stages.
The data showed that Miami-Dade County in Florida had the highest proportion of residents over 65 years old with Alzheimer’s disease, at about 16.6 percent of the population.
Although Miami is famous as a party destination, researchers pointed out that it has a large black and Hispanic population — who are at up to 2.5 times higher risk of the disease than their white counterparts.
They said that other areas with the highest rates also tended to have more ethnically diverse populations, driving up estimates of the proportion of people with the disease.
In terms of population, the county with the largest population of people with Alzheimer’s disease were Los Angeles county (1.4million people), Cook County, Illinois (792,000) and Maricopa County, Arizona (729,000).
The above pie chart was created from data from Rajan et al. The percentages do not total 100 due to rounding
In the three top places — Miami, Baltimore and the Bronx — an estimated one in six have the condition. Rounding out the top five counties for Alzheimer’s disease sufferers were Prince George’s County in Maryland (16.1 percent) and Hinds County, Mississippi (15.5 percent)
Miami-Dade County was fourth on the list at 459,000 and Harris County, Texas, was fifth at 532,000.
At the national level, researchers said that Alzheimer’s was most common in the Eastern and Southeastern regions of the US.
Scientists calculated the estimates using data from the Chicago Health and Aging Project, which tracked 10,000 individuals over 65 years old for nearly two decades to reveal which developed health problems — including Alzheimer’s.
Researchers used this data to then estimate the proportion of residents in each county that had Alzheimer’s, based on the age breakdown of each county as well as their sexes and ethnicities.
At the other end of the scale, they found that sparsely populated counties with low older populations in Alaska, Texas, Colorado and South Dakota had the lowest proportion of residents with Alzheimer’s. Some remote counties were estimated to have less than one in 20 people affected.
The report also found that people in their 80s were much more likely to have the disease than those in a younger age group.
People aged 85 years and up were 15 times more likely to have the disease than people aged 65 to 69, they said, while those aged 75 to 79 years were about three times more likely to have it.
Senior women were also about 13 percent more likely to be struck with Alzheimer’s than men, the report added.
Broken down by ethnic group, rates among black seniors were about 2.5 times higher than those among their white counterparts.
Dr Kumar Rajan, an internal medicine expert at Rush Medical College in Chicago who led the study, told CNN: ‘Half, or even over half, of people who are living with Alzheimer’s disease and related dementias are actually undiagnosed.
‘Why that happens is complex.
‘Some individuals and families don’t recognize it to be dementia, confusing it with normal aging. And we know that clinicians don’t always ask about it, so it doesn’t come up unless the family brings it up. And clinicians may be reluctant to make and share the diagnosis.’
He added that some cities like Baltimore may have had higher rates because of a larger black population. He said on Baltimore: ‘This is a major Black city, and the root of all this really is the segregation in the city neighborhoods that goes back decades.’
About 6.7 million Americans have Alzheimer’s disease, according to the AAIC.
Imperial county in California has the highest number of patients, with a rate of 15 percent.
But population projections suggest that the west and south-west regions of America will likely see patient numbers shooting up in the coming years.
Matthew Baumgart, the AAIC’s vice-president of health policy, said: ‘As the prevalence of Alzheimer’s disease increases, so does the need for a larger workforce that is trained in diagnosing, treating and caring for those living with the disease.’
This week, in a ‘defining moment’ for dementia research, results from trials of donanemab found it significantly delayed the worsening of symptoms in people with Alzheimer’s.
Projected yearly incidence of dementia on the basis of current rates (solid lines) and projected incidence of dementia assuming continuation of a decreasing trend (dashed lines)
Donanemab is given to Alzheimer’s patients through an IV infusion once a month. The monoclonal antibody — a man-made version of proteins produced by the body to fight off harmful substances — travels to the brain. Once inside the organ, donanemab binds to toxic build-ups of amyloid plaque — a hallmark sign of the memory-robbing disease. This prompts immune cells, known as microglia, to clear them
Scientists said it also ended the decades-long debate over whether the accumulation of sticky plaques, or amyloid, is at least partly responsible for the degenerative disease.
Donanemab is given to Alzheimer’s patients through an IV infusion once a month. The monoclonal antibody — a man-made version of proteins produced by the body to fight-off harmful substances — travels to the brain.
Once inside the organ, donanemab binds to toxic build-ups of amyloid plaque — a hallmark sign of the memory-robbing disease. This prompts immune cells, known as microglia, to clear them.
It comes after Eisai and Biogen’s lecanemab was shown to slow decline by 27 per cent, leading to its FDA approval earlier this month.
Scientists said the successes of both donanemab and lecanemab ended the decades-long debate over whether the accumulation of sticky plaques — amyloid — is at least partly responsible for the degenerative disease.
