Political efforts from the UK and US to screen older people for early signs of dementia could lead to unnecessary investigation and potentially harmful treatment for an “inevitable consequence of aging,” according to an analysis published in BMJ.

Recent government policy directives have called for regular screening of older people to test for mild cognitive impairment, also known as pre-dementia.

In the US, the Medicare insurance program, launched under the new Affordable Care Act, will include the cover of annual wellness visits to physicians in which older patients will be tested for cognitive impairments and any changes in thinking abilities.

In England, the government has announced that general practitioners will be rewarded £3,600 (USD 5,600) annually for assessing patients over the age of 75 and high-risk patients over the age of 60 for cognitive impairment and dementia.

But according to the researchers from the UK and Australia, there is no sufficient evidence to show that these early screenings will be beneficial.

Only 5-10% of people with mild cognitive impairments will progress to dementia each year, the researchers say. They add that as many as 40-70% of these do not progress at all, or even experience improvements in their cognitive functions.

Additionally, they point to previous studies, which have shown that the clinical tools doctors use to diagnose dementia, such as imaging techniques and memory tests, are not powerful enough. They note that these tools are still increasingly used in diagnosis, even though there is uncertainty over their accuracy.

The researchers say the “influence of old age outweighs all biomarkers and risk factors,” and that biomarkers become less accurate in older people, who experience higher prevalence of dementia.

Taking this into consideration, they say the early screening of dementia could result in 65% of people over the age of 80 being diagnosed with Alzheimer’s disease, and 23% of older people being misdiagnosed with dementia.

Furthermore, the researchers say that as there are currently no drugs to prevent the progression of dementia, there are concerns that once a person is diagnosed with a mild cognitive impairment, they may embark on “untested therapies,” leading to adverse effects.

The study authors warn that “the desire of politicians, dementia organizations, and academics and clinicians in the field to raise the profile of dementia is understandable, but we risk being conscripted into an unwanted “war against dementia.”

They continue:

Nearly half of the people who have positive results on screening for cognitive impairment refuse subsequent diagnostic evaluation because of concerns about harms associated with a diagnosis such as losing health insurance cover, driving privileges, or employment; anxiety and depression; stigma; and effect on family finances and emotions.”

The authors add that although the strong political lead in the UK and US is clearly increasing the numbers of people who receive a diagnosis of dementia and early dementia, people would benefit more if there was greater focus on combatting risks linked to the disorder.

“Arguably the political rhetoric expended on preventing the burden of dementia would be much better served by efforts to reduce smoking and obesity, given current knowledge linking mid-life obesity and cigarettes with the risk of dementia,” they add.

“Although increasing the diagnosis rates might raise awareness and perhaps fear of dementia in the community, there is a risk it will result in reallocating resources that are badly needed for the care of people with advanced dementia.”

However, UK charity the Alzheimer’s Society has strongly disputed the study’s claims, saying that population screening does not currently exist in the UK and there are currently no plans to introduce it.

They add that the charity supports the current approach to diagnosing dementia, where clinicians ask those who are at higher risk of developing dementia if they are concerned about their memory, and if so, refer them to have appropriate tests.

Jeremy Hughes, chief executive of the Alzheimer’s Society, says:

It’s astounding to hear talk of an ‘unwanted war’ on dementia when in fact we need nothing less than an all out fightback. We should be backing doctors up and down the country who are helping ensure people with dementia are diagnosed”

“Discussion of screening is irrelevant as no one is advocating its introduction,” he continues. “There is surely no other condition where we could tolerate, let alone encourage, people being kept in the dark, without treatments or support and unable to make decisions about their life.”

“The huge human cost of dementia is matched only by the spiralling cost to the economy of people with the condition who reach crisis point and need expensive hospital care. By 2021, a million people [in the UK] will have dementia. We cannot afford to bury our heads in the sand over the condition.”