Blood test could revolutionise Alzheimer's diagnosis

We are all probably familiar with the Theranos story, the company that promised rapid, accurate blood tests using very small amounts of blood to diagnose a range of illnesses. It all turned out to be a fraud with the founders Elizabeth Holmes and Sunny Balwani sent to jail.

However, early diagnosis can be absolutely critical in getting better patient outcomes in the long run. Making the screening or testing as easy and comfortable for the patient as possible encourages uptake.

That is why the news of a blood test that could identify early signs of Alzheimer's caught our eye.

Blood test could revolutionise diagnosis of Alzheimer’s, experts say

Study finds measuring levels of a protein could be just as good at detecting disease as lumbar punctures and scans

The GuardianNicola Davis

An existing commercially available blood test for p-tau217, a well-known biomarker for changes in the brain associated with Alzheimer's disease, called ALZpath was evaluated by researchers at Gothenburg University. They found that when compared with much more invasive procedures currently used for detection (examining cerebrospinal fluid following a lumbar puncture, also known as a spinal tap), the accuracy of the blood test was similar. The study included 786 participants.

Early interventions can reduce the risk of Alzheimer's disease development including basic ways of staying generally healthy both physically and mentally. But in addition, two recently approved drugs, donanemab (Eli Lilly) and lecanemab (Biogen / Eisai) have been shown to slow cognitive decline in Alzheimer's patients at particular stages of the disease development. So potentially a broader cohort of patients could benefit if they are identified early. Indeed there is some discussion about implementing national screening plans similar to those for bowel cancer.

There are 55 million people with dementia globally and that is expected to rise to almost 153 million people by 2050. The estimated global cost of medical, social and informal care associated with dementia in 2019 was more than US$1.3 trillion with more than half attributable to care provided by informal carers.

It is also a disease that disproportionately impacts women. The female-to-male ratio of people with the dementia is 1.69 and women experience higher disability-adjusted life years (how many years of life expectancy are lost due to early death or years lived with a disability) due to dementia. In addition they are also indirectly impacted as women also provide 70% of care hours for people living with dementia.

Amongst the environmental risk factors is air pollution. In a previous blog, we discussed research from the Harvard TH Chan School of Public Health which concluded that PM_2.5 might be a risk factor for dementia and interestingly the link between PM_2.5 and clinical dementia seemed to exist below the current US Environmental Protection Agency (US EPA) annual standards and well below the UK and EU limits.

Link to blog 👇🏾

Air pollution and dementia

As the World population life expectancy increases, more of us are likely to succumb to ‘old age’ conditions like dementia. There are a number of factors thought to play a part. Is air pollution one of them?

The Sustainable InvestorSandy Jayaraj

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