‘Pre-dementia’ more common than thought, study finds

CHICAGO — A milder type of mental decline that often precedes Alzheimer’s disease is alarmingly more common than has been believed, and in men more than women, doctors reported Monday.

Nearly a million older Americans slide from normal memory into mild impairment each year, researchers estimate, based on a Mayo Clinic study of Minnesota residents.

That’s on top of the half-­million Americans who develop full-blown Alzheimer’s or other forms of dementia — a problem sure to grow as baby boomers age. The oldest boomers turn 62 this year.

ADVERTISEMENT
0 seconds of 0 secondsVolume 0%
Press shift question mark to access a list of keyboard shortcuts
00:00
00:00
00:00
 

“We’re seeing that in fact there’s a much larger burgeoning problem out there” of people at risk of developing dementia, said Dr. Ronald Petersen, the Mayo scientist who led the study.

The mild impairment rate is two to three times larger than many researchers had expected, he said.

Petersen is the scientist who defined mild cognitive impairment, or MCI, as a transition phase between healthy aging and dementia. It is more than “senior moments,” like forgetting where you parked the car, but not as severe as having dementia, where you forget what a car is for.

People with it have impaired memory but not other problems such as confusion, inattention or trouble putting thoughts into words.

The Alzheimer’s Association says more than 5 million Americans have Alzheimer’s, but no estimate for this “pre-dementia” has been available until now.

Petersen’s federally funded study involved roughly 1,600 people, ages 70-89. All tested normal when they were enrolled in the study, but more than 5 percent had developed mild impairment when evaluated a year later.

Men were nearly twice as likely as women to develop it. That’s a surprise, because some studies have found more women with Alzheimer’s than men. But while more men may be impaired, women outlive them and therefore have more time to develop full-blown dementia.

There are no treatments now to prevent the mental slide of dementia or reverse it once it starts.

Talk to us

> Give us your news tips.

> Send us a letter to the editor.

> More Herald contact information.

More in Local News

Cars drive along Cathcart Way next to the site of the proposed Eastview Village development that borders Little Cedars Elementary on Wednesday, May 7, 2025 in unincorporated Snohomish, Washington. (Olivia Vanni / The Herald)
Former engineer: Snohomish County rushed plans for Eastview development

David Irwin cited red flags from the developers. After he resigned, the county approved the development that’s now stalled with an appeal

Outside of the Madrona School on Monday, Aug. 26, 2024 in Edmonds, Washington. (Olivia Vanni / The Herald)
Sewer district notifies Edmonds schools of intent to sue

The letter of intent alleges the school district has failed to address long-standing “water pollution issues” at Madrona K-8 School.

Everett
Man stabbed in face outside Everett IHOP, may lose eye

Police say the suspect fled in the victim’s car, leading officers on a 6-mile chase before his arrest.

A person walks up 20th Street Southeast to look at the damage that closed the road on Wednesday, Nov. 20, 2024 in Lake Stevens, Washington. (Olivia Vanni / The Herald)
WA delegation urges Trump to reconsider request for bomb cyclone aid

The Washington state congressional delegation urged President Donald Trump on… Continue reading

Aaron Weinstock uses an x-ray machine toy inside the Imagine Children Museum on Tuesday, Dec. 3, 2024 in Everett, Washington. (Olivia Vanni / The Herald)
Imagine Children’s Museum $250k grant reinstated following federal court order

The federal grant supports a program that brings free science lessons to children throughout rural Snohomish County.

Snohomish County 911 Executive Director Kurt Mills talks about the improvements made in the new call center space during a tour of the building on Tuesday, May 20, 2025 in Everett, Washington. (Olivia Vanni / The Herald)
New 911 center in Everett built to survive disaster

The $67.5 million facility brings all emergency staff under one roof with seismic upgrades, wellness features and space to expand.

Everett
Five arrested in connection with Everett toddler’s 2024 overdose death

More than a year after 13-month-old died, Everett police make arrests in overdose case.

Madison Family Shelter Family Support Specialist Dan Blizard talks about one of the pallet homes on Monday, May 19, 2025 in Everett, Washington. (Olivia Vanni / The Herald)
Madison Family Shelter reopens after hiatus

The Pallet shelter village, formerly Faith Family Village, provides housing for up to eight families for 90 days.

The age of bridge 503 that spans Swamp Creek can be seen in its timber supports and metal pipes on Wednesday, May 15, 2024, in Lynnwood, Washington. The bridge is set to be replaced by the county in 2025. (Ryan Berry / The Herald)
Snohomish County report: 10 bridges set for repairs, replacement

An annual report the county released May 22 details the condition of local bridges and future maintenance they may require.

Traffic moves north and south along the southbound side of the Highway 529 after the northbound lanes were closed due to a tunnel on Tuesday, July 2, 2024 in Everett, Washington. (Olivia Vanni / The Herald)
Southbound 529 to close near Marysville for four days for bridge work

WSDOT said the 24-hour-a-day closure is necessary to allow contractors to perform work on the aging Steamboat Slough Bridge.

The Edmonds City Council gathers to discuss annexing into South County Fire on Tuesday, Dec. 3, 2024 in Edmonds, Washington. (Olivia Vanni / The Herald)
Community group presents vision for Edmonds’ fiscal future

Members from Keep Edmonds Vibrant suggested the council focus on revenue generation and a levy lid lift to address its budget crisis.

People listen as the Marysville School Board votes to close an elementary and a middle school in the 2025-26 school year while reconfiguring the district’s elementary schools to a K-6 model on Wednesday, Jan. 22, 2025 in Marysville, Washington. (Olivia Vanni / The Herald)
Marysville schools audit shows some improvement

Even though the district still faces serious financial problems, the findings are a positive change over last year, auditors said.

Support local journalism

If you value local news, make a gift now to support the trusted journalism you get in The Daily Herald. Donations processed in this system are not tax deductible.