Does dementia screening do more harm than good?

Alzheimer’s disease health centre


WebMD UK Health News
Medically Reviewed by Dr Keith David Barnard

10th September 2013 – Around two-thirds of people over 80 could be diagnosed with dementia because doctors are being encouraged to carry out unnecessary investigations and prescribe potentially harmful treatments, experts are warning.

A group of geriatric, dementia and public health specialists from Australia and the UK say the growing trend towards more screening amounts to a “war against dementia” with the risk of considerable over-diagnosis.

However, one UK dementia charity disputes the claims and says doctors should be supported for helping people with the condition to access early treatment.

Risk increases with age

There are currently around 800,000 people with dementia in the UK and estimates suggest this will increase to over a million by 2021.

Although dementia can affect younger people, the risk of getting the condition increases with age.

It is estimated that more than half of those people with dementia are undiagnosed, with only 44% of people in England, Wales and Northern Ireland having a diagnosis.

Politically motivated

However, writing on, the specialists say there is a move towards more screening which is politically driven and led by the UK and the US. They argue, though, that this policy is not backed by evidence and ignores the risks, harms and costs to individuals, families and societies. The authors say that there are no drugs that prevent the progression of dementia or are effective in patients with mild cognitive impairment and none is recommended for these purposes. There is then the risk that once patients are labelled with early disease, they may try unproven treatments such as vitamin E, gingko biloba and other remedies marketed with unsubstantiated claims. The authors state that just attending a memory clinic generates stress for patients and their carers, and uses unnecessary and expensive investigation techniques including neuroimaging. While some people are positive about the value of memory clinics, there is evidence that they may be no more effective than standard care by general practitioners. All this activity  may divert resources that are badly needed for the care of people with advanced dementia, they say.

They warn that more screening will result in up to 65% of people aged over 80 having Alzheimer’s disease diagnosed – and up to 23% of non-demented older people being labelled with dementia.

However, they say, the evidence suggests that while 5 – 15% of people with mild cognitive impairment will progress to dementia each year, as many as 40 – 70% will not develop the condition and could even see their thinking skills improve. Furthermore, studies have shown that the screening techniques used by doctors to diagnose dementia are not sufficiently reliable.

‘Commercial opportunity’

The specialists also question whether an ageing population is becoming a “commercial opportunity” with the development of screening, early diagnostic tests and medicines that can be marketed in the hope of maintaining brain function in old age.

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

They suggest that the political rhetoric expended on preventing the burden of dementia would be better served by efforts to reduce smoking and obesity, given current knowledge linking mid-life obesity and cigarettes with the risk of dementia.

“Current policy is rolling out untested and uncontrolled experiments in the frailest people in society without a rigorous evaluation of its benefits and harms to individuals, families, service settings, and professionals,” they conclude.

Their views coincide with the Preventing Overdiagnosis conference opening in New Hampshire in the US, where international experts are discussing how to tackle the threat to health and the waste of money caused by unnecessary care.

‘An all-out fightback’

The Alzheimer’s Society says it disagrees with the analysis put forward. Its chief executive Jeremy Hughes says in a statement: “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. 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… We cannot afford to bury our heads in the sand over the condition.”