The pattern of over-diagnosis is the same for many diseases: we screen healthy people and those with minimal symptoms; we use sophisticated technologies that detect early or minor abnormalities that may not progress; and we treat people with these abnormalities on the assumption that this will prevent significant illness and death.

The downside of all this medical intervention is that we're exposing healthy people to the potential harms of diagnosis, investigation and treatment without any certainty about long-term benefits. Indeed, there's a growing unease that this trend is being driven by the financial benefits of creating a larger market for drugs rather than genuine health gains.

I work in geriatric medicine and over the last few years, I have seen how the changing definitions of dementia and Alzheimer's disease has insidiously been leading to over-diagnoses.

Screening the healthy

Let's start with the schema of over-diagnosis: are we screening healthy people and those with minimal symptoms? Yes. In the past, we diagnosed older people complaining of minor memory impairment with "benign senescent forgetfulness", and told them that it didn't require any further action. It was, after all, benign.

But this terminology progressed to "mild cognitive impairment (MCI)" and now (more ominously), to pre-dementia and pre-clinical Alzheimer's disease. We are also being encouraged to screen older people for any memory impairment because this has now been defined as a pre-disease or early disease.

The screening tools are usually simple questionnaires, such as the mini-mental state examination (MMSE). There's variability in how well the assessments are performed, and forgetting the date or stumbling on a repetition task can lead to a diagnosis of mild cognitive impairment. But how many of these people actually progress to dementia?

Most studies show that only one in ten cases of mild cognitive impairment progress to dementia each year, and many improve. One study that followed outcomes for ten years concluded - "The majority of subjects with MCI do not progress to dementia at the long term." Read more

Sources

• The Conversation
• Image: TopNews.in

Preconditions don't always lead to actual conditions, but that doesn't stop millions of Americans from seeking treatment of some kind anyway. In fact, over 100,000 people die every year due to complications associated with treating preconditions, according to Ivan Oransky, the executive editor of Reuters Health, who spoke yesterday at TEDMED, a three-day conference in Washington, D.C. on technology and medicine.

As with many of the challenges facing the country's healthcare system, the profit motive has a large role to play in exacerbating the prediagnosis epidemic. Making treatments available for preconditions does more than enable more frequent diagnoses of said illnesses, Oransky believes. It actually creates greater demand in a weird kind of feedback loop, because people want to believe that every medical ailment has a ready medical solution.

"You can actually, perversely, tell people to come" and be diagnosed with preconditions, Oransky told TEDMED attendees. "You can convince them that they have to come."

"I have another name for these preconditions," Oransky added. "I call them preposterous."

In many cases, he said, over-medicalization may be counterproductive. Instead of developing better lifestyle habits, patients go to doctors seeking drugs, which are provided by pharmaceutical companies aiming to sell as many pills as possible. Meanwhile, precondition advocacy groups whose survival depends on successful fundraising have an interest in perpetuating the idea that preconditions are themselves diseases that must be treated medically.

It's hard to know whether better living can eliminate all preconditions. But the culture of precondition diagnosis may be doing more harm than good.

"I have really bad news for all of you," Oransky said. "You all have a universally fatal condition. It's called pre-death. Every single one of you has it, because you have the risk factor for it, which is being alive."

Sources

• Brian Fung in The Atlantic
• Image: NewScientist