Hi-tech specs that cut the risk of a stroke

SPECTACLES that monitor blood pressure throughout the day could cut the risk of heart attacks and strokes. The high-tech glasses — being developed by technology giant Microsoft — have hidden sensors at various positions in the frames that monitor the rate that blood is being pumped every few seconds.

This gives a reading called pulse transit time, which is the time it takes for the heart to pump blood through various points of the body. Doctors then use this to calculate blood pressure.

High blood pressure — or hypertension — is a reading above 140/90. It affects one in five adults in the UK and is responsible for half of all heart attacks and strokes.

The majority of patients need pills to control it, which they must take for the rest of their lives. But diagnosing hypertension can be difficult as blood pressure can vary significantly throughout the day and many patients with otherwise normal readings can experience a spike brought on by anxiety during a visit to a doctor’s surgery — known as white-coat hypertension.

To get round this, Gps use ambulatory blood pressure monitoring — where the patient wears a cuff around the upper arm attached to a monitor that clips onto a waistband and takes blood pressure readings round-the-clock.

THIscan build up a picture of how blood pressure changes during the day. But these devices are bulky and uncomfortable — and the high-tech glasses, currently under development, could be an easier alternative.

Called Glabella, they look like ordinary specs — but their chunky frames contain three sensors.

One is in the frame just in front of the nose; the second sensor sits in front of the right ear; the third is in the frames just behind the right ear.

These locations are chosen because they are where prominent arteries, which supply blood to the nose, neck, back of the head and scalp, are situated close to the surface of the skin.

Every few seconds, the sensors record pulses in these arteries and send the findings to a tiny processor hidden in the right ‘arm’ of the glasses. This processor then wirelessly sends the data to a computer, where the pulse transit times can be used to calculate blood pressure.

In a healthy body, blood vessels are pliable and elastic and blood flows slowly but steadily.

Unhealthy blood vessels tend to be stiffer — and this means they are less likely to give way when blood presses against them, so blood flows more quickly.

When the speed of this flow is measured between two points — the pulse transit time — it allows doctors to calculate blood pressure. By measuring these pulses tens of thousands of times a day, the glasses can give an accurate estimate of blood pressure.

so far, they have only been tested on four people who wore them for five days and the results have yet to be published.

participants also took blood pressure readings with a standard cuff and the manufacturer reported that the blood pressure results for both were comparable in terms of accuracy.

previously, a 2014 study by scientists at the Jimenez Diaz University Hospital in spain showed pulse transit time was nearly 90 per cent accurate at measuring blood pressure compared with using an inflatable cuff.

Maureen Talbot, a cardiac nurse with the British Heart Foundation said: ‘This is a novel and less invasive approach. It will be interesting to see if they can turn science fiction into a reality.’

MEANWHILE, a simple test commonly used to spot brain decline should be given routinely to patients with high blood pressure, say cardiologists.

For the test, patients are told to draw a clock by hand on a piece of paper; any difficulty may be a sign of early dementia.

In a new study presented at the European society of Cardiology conference, doctors found more than a third of patients with high blood pressure showed signs of early dementia based on the clock drawing test results.