I generally shy away from wearing my Apple Watch while sleeping. Yes, I can mute notifications on the watch to avoid audio-visual distractions on my wrist. I’m fine waking up to a phone alarm and don’t need the watch to press beeps into my ears.
The disdain is somewhat justified since I bought the smartwatch primarily for exercise tracking. Plus, I just can’t sleep with a device on my wrist. It’s just uncomfortable. But attitudes have softened recently.
My GP recently forced me to close my eyes for at least 7-8 hours to ensure my seizures don’t recur. And since I’m required to submit a record of my sleep data for monthly evaluation, I do my best and take the watch to bed with me.
But it seems the Apple Watch has done more for my sleep – and my overall health – than I knew. Or even what Apple advertised. And I think I’ll get into the habit of sleeping with the Apple Watch on, whether I like it or not, for the good of my heart and neurological health.
New research has just found that deviating from your usual bedtime routine can increase your risk of sleep apnea and high blood pressure. And here’s the fun part. The Apple Watch already has a metric that keeps an eye on your sleep patterns and can also measure blood pressure spikes.
Which ultimately changed my mind
Scientists at Scripps Research, a leading nonprofit biomedical research organization, analyzed the effectiveness of digital activity trackers such as the Apple Watch, Fitbit wearables and the Oura Ring. The aim was to evaluate the sleep data as part of a study called the Research Framework for Exploring Sleep Health (REFRESH).
The team recruited over a thousand adults across the country and contributed an average of two years of sleep data collected from wearable devices. The main goal was to study their sleep behavior and broadly categorize them as night owls or early risers. At the end of the study, the team found that even delaying routine bedtime by an hour significantly increased the risk of sleep apnea and high blood pressure.
The findings, published in the Journal of Medical Internet Research, found that a one-hour delay in participants’ regular bedtime “more than doubled their risk of sleep apnea and was 71 percent more likely to have high blood pressure.”
The team calls it a “robust” and “compelling link” between sleep variability and health conditions such as sleep apnea and elevated blood pressure, and makes the case that wearable devices like the Apple Watch can be used for early detection and prevention of disease.
“Right now we are in the pattern recognition phase. We are confirming that these relationships exist and understanding mechanisms,” Stuti Jaiswal, assistant professor at Scripps Research, was quoted as saying. However, the impact could be significant for millions of people around the world, including me.
The Apple Watch already tracks my bedtime discipline
Obstructive sleep apnea (OSA) affects nearly one billion people worldwide, according to an article published in the Lancet Respiratory Medicine. In the US, estimates vary between 30 and 60 million adults, a number expected to reach a staggering 77 million by 2050.
Sleep apnea can vary in severity, but the effects are profound. In severe cases, impairments in perception, mood and daytime attention can occur. Studies have also suggested a high prevalence of cardiac arrhythmias in patients with severe sleep apnea. It is well known that sleep apnea is associated with an increased risk of cardiovascular and metabolic problems.
And here’s the scariest part. “You may not even know you have this very common problem,” note the experts at John Hopkins Medicine. Fortunately, Apple Watch can now detect signs of moderate to severe sleep apnea by keeping an eye on your body’s movement while you sleep to detect breathing disorders.
According to the latest study from Scripps Research, your bedtime may have an impact on your risk of sleep apnea. This is where Apple’s latest sleep scoring system comes into play. This new feature takes into account three core metrics: sleep duration (50 points), interruptions (20 points), and how closely you follow your bedtime schedule (30 points).
Based on these three values, the Apple Watch assigns a value between 0 and 100, divided into five quality levels. The Scripps Research study focuses on the latter aspect, namely how closely you stick to bedtime schedules. Apple has been tracking this metric for months and I’m finally seeing its true meaning.
A deeper look into blood pressure problems
The Apple Watch also has a feature called Hypertension Notifications. As the name suggests, it can detect and alert users to high blood pressure, also called chronic hypertension. Over a billion people around the world are affected by high blood pressure, which increases the risk of heart attack, stroke and kidney disease.
The most concerning thing is that, just like sleep apnea, there are no telltale symptoms of high blood pressure. The Apple Watch helps here. The smartwatch’s optical biosensor measures how blood vessels contract and expand as the heart beats and uses an algorithm to detect abnormal movements.
This ties in with the latest research. If you get a high blood pressure alert on your Apple Watch and aren’t sure what to do next, you can check your sleep history and see if your bedtime has been consistent recently. This can be done either by looking at your sleep assessment logs or even overall sleep history.
And while you’re at it, you might also want to take a look at the Vitals app, which tracks five metrics overnight – heart rate, breathing rate, blood oxygen level, wrist temperature and sleep duration. Of course, the best thing to do is to see a doctor. But with insights into bedtime history, you will have other important insights to share with your doctor to make a more accurate diagnosis.
Experts at Scripps Research caution that more analysis is needed to understand the depth of the interaction between sleep schedules and high blood pressure risks, but they can already see a visible link. I’m just glad that the Apple Watch on my wrist can already measure these measurements and I can reliably monitor them for my physical well-being. And if that means I have to wear it to bed, I’m willing to live with the inconvenience.
