The lifesaving health benefits of wearing a smartwatch

For the past 13 years, David George has suffered from atrial fibrillation or AF, a terrifying condition where the heart suddenly begins beating irregularly, often accelerating out of control without warning.

George, now 70, was forced to take early retirement from his job as a management consultant in the construction of power stations and petrochemical plants, because his episodes of AF could last for up to 16 hours at a time.

“It was a nightmare,” he says. “You’re very conscious of your heart jumping around in your chest, you feel breathless, and it gives you this strange feeling in the pit of your stomach.”

While cardiologists can attempt to treat the condition through catheter ablation, which involves targeting faulty nerves in the heart and heating or freezing them, the symptoms return in 20-50 per cent of cases. While George has been through two ablations, he still experiences periodic bouts of AF.  Untreated the condition can lead to heart failure and increases the risk of a stroke by five times.

But in the past year, a new way of monitoring his condition has emerged – a smartwatch. George is currently participating in a clinical trial for AF run by Barts Heart Centre in London, in which all patients have been fitted with an Apple Watch which monitors their heart’s electrical activity and remotely transmits the data back to cardiologists at the hospital.

One of the aims is to see whether this can help predict in advance when the AF symptoms are going to reoccur. Being able to do this accurately would enable preventative treatment, something that could greatly improve long-term patient survival rates.

“If it comes back, we can retreat with ablation,” says Nikhil Ahluwalia, a cardiologist at Barts Heart Centre. “We can mitigate the risk of a stroke with blood thinner tablets, while AF can also lead to other heart rhythm disorders, which we want to see if we can detect.”

Lifesaving benefits

The smartwatch market is booming – for example, statistics show that 45 per cent of all Americans now own one – and research is increasingly indicating that they could have lifesaving benefits. In April, a study published in the European Heart Journal – Digital Health by University College London researchers, found that smartwatch style ECG measurements can detect middle-aged adults with an extra heartbeat. This can be an early indicator of cardiovascular disease.

For patients with a family history of heart problems, the devices are already providing a degree of reassurance. Despite being an active 48-year-old, Rupert Lee has always been concerned about his heart health, having seen his mother develop AF at a similar age.

“After playing sport one evening, I couldn’t get to sleep because my heart was thumping about so much inside my rib cage,” he says. “I was concerned so I used my smartwatch to take an ECG reading, exported the PDF and took it to my GP who said he could detect signs of a small irregularity.”

Lee was referred to Guy’s Hospital in London, where he received a full echocardiogram of his heart. “Happily, it concluded that there was ultimately nothing serious for me to worry about, but being able to have that data and show it to a doctor was reassuring, because when your heart is stomping about your chest, you want to know whether there’s a problem,” he says.

There are some downsides of wearables, such as their cost (upwards of £300-£400) and the potential anxiety they may cause users, as well as people reporting to their GP with apparent health concerns, which turn out to be spurious. “I certainly feel that if I was going around wearing something that told me how my heart or lungs are functioning the whole time, that would make me slightly health anxious,” says Jeremy Smelt, a consultant thoracic surgeon at St George’s Hospital NHS Foundation Trust.

Advancing technology

However this is unlikely to dent the rapid growth in interest in using smartwatches and other wearables to usher in a new era of preventative health. As well as brands such as Apple Watch and Fitbit, newer devices such as the Masimo W1 are entering the market. The latter is a smartwatch that can measure how well hydrated you are, as well as blood oxygen levels – a marker of how well your heart and lungs are functioning – to hospital level accuracy. Poor blood oxygen levels can be a sign of an underlying respiratory illness such as pneumonia, which requires urgent medical attention.

Earlier this month, Cardiff University researchers published a study in the journal Nature Medicine which suggested that smartwatches could detect early signs of Parkinson’s disease, up to seven years before patients develop tremors and other clinical symptoms. Based on data from more than 100,000 people who were given a smartwatch to wear for a week, the researchers could detect irregularities in walking speed and other forms of light physical activity which were unique to those who later developed Parkinson’s.

Being able to spot Parkinson’s much earlier could be crucial when it comes to finding better treatments for the disease. Right now, patients tend to be diagnosed far too late, at a point where they have already suffered irreversible degeneration of the brain and central nervous system.  Researchers have long speculated that one of the reasons Parkinson’s treatments have been largely unsuccessful, is because they’re given too late in the day. The big hope is that if we can identify the disease at a much earlier stage, it will be easier to find drugs that can tackle the underlying causes.

‘It helps keep me accountable’

But as well as being used to diagnose chronic disease at a much earlier stage, smartwatches are also increasingly being explored as a way of helping patients manage a health condition – and prevent it from getting more serious.

In March 2023, 39-year-old Lorraine Marsh, a jeweller from Tunbridge Wells who runs a business called the Diamond Setter, received a shock diagnosis of prediabetes. This is a condition where patients have blood sugar levels that are higher than normal, but not yet high enough to warrant a diagnosis of Type 2 diabetes.

Marsh was swiftly assigned an appointment with a coach from the NHS Diabetes Prevention Programme. “They said it’s a serious health condition but it’s reversible by changing a little bit of your lifestyle and your habits,” she says.

To her surprise, her coach recommended using her Fitbit smartwatch as a way of keeping track of her progress, monitoring her daily activity levels and particularly her sleep. “For a prediabetic, sleeping habits can have a major impact,” says Marsh. “If I’ve slept less than seven or eight hours, I’m craving sugar, coffee, fizzy drinks, which isn’t helping. So having that data is useful, because if I’ve seen I’m not getting sufficient sleep, I can try to go to bed earlier, or not check my phone before I go to sleep, little steps like that.

“While I’ve only been doing it for a month now, I can feel it’s already making a difference and my coach can see the data too, which helps keep me accountable.”

Patient tracking

In future, smartwatches could also provide a better way for hospitals to keep track of patients, enabling them to be discharged earlier, freeing up beds and reducing their risk of being infected with a hospital-acquired superbug. The US has led the way with this kind of remote monitoring, back in 2019, New York’s Mount Sinai Hospital was already experimenting with discharging patients with Wi-Fi enabled armbands that tracked their oxygen levels, blood pressure and body temperature. Yet the UK is swiftly catching up.

In May, Cambridge University Hospitals NHS Foundation Trust announced that they were using the Masimo W1 smartwatch as part of their new virtual ward program, which is seeing patients with conditions ranging from congestive heart failure to pneumonia, discharged faster than normal. The data recorded by the watch, which includes pulse rate, blood oxygen levels and information on the heart’s electrical activity, is fed back in real-time to a dashboard monitor where doctors can track the progress of dozens of patients simultaneously.

According to Iain Goodhart, an anaesthetist and intensive care consultant, who acts as clinical director of the virtual ward programme, the Government has been increasingly pushing for this kind of remote monitoring as a way of tackling NHS backlogs, which have reached crisis point.

“There’s a huge backlog of operations after Covid, but the number we can do is limited by hospital bed availability,” says Goodhart. “If we can use the virtual ward to reduce patients’ length of stay, we can get more surgery done.”

‘Just the beginning’

But according to tech leaders, this is all just the beginning of how wearables are going to be used to detect abnormalities relating to our health. According to Joe Kiani, CEO of Masimo, as smartwatches get better at measuring changes in our walking gait, particularly as we age, they could be used to alert doctors or family members that an elderly patient is becoming frailer, and at a greater risk of falling.

He also predicts that they could soon be capable of detecting whether someone is about to have an asthma attack, a medical need that was inspired by his own son.

“At Masimo, we’re working on a way of measuring respiratory effort,” says Kiani. “My son, Mike, had childhood asthma, which is how I learnt about this. Before an asthma attack, respiration rate increases, pulse rate increases because the body’s trying to make up for the lack of oxygen it’s getting, and if you can pick that up and alert the patient that they need their inhaler, it can keep them out of hospital.”

For patients like George, who are already managing a chronic condition, knowing that their health status is being continuously monitored by a medical professional, helps to provide a degree of peace of mind.

“I feel like I’ve got this distance support, where if I have an episode, I send the data off in an email, describe the symptoms, and sometimes I get a reply in half an hour,” says George. “It’s reassuring to know that someone from afar is watching what’s happening, because before I felt quite alone and isolated.”

Five smartwatches for your health

Clockwise from top left: Masimo W1; Apple Watch; Fitbit, Versa 2; Samsung Galaxy Watch5; Withings ScanWatch

Masimo W1, £435

This smartwatch can measure blood oxygen levels, heart rate, respiration rate and pulse rate to medical-grade accuracy. Can also tell how hydrated or dehydrated you are.

Apple Watch Series, from £419

The Apple Watch is being used in clinical trials in both the US and UK to monitor serious heart conditions such as atrial fibrillation and heart failure.

Fitbit, Versa 2, £99.99

As well as being good for step counting and activity levels, the Fitbit can keep track of sleep duration and quality.

Samsung Galaxy Watch5, £239

Through internal sensors, this smartwatch can keep track of your blood pressure at all times.

Withings ScanWatch, £279.95

As well as monitoring ECG, the Withings ScanWatch can analyse your sleep and track any disturbances in your breathing.