06 July 2015

SLEEP STUFF: Smartphone apps for sleep

Probably more popular than any other category of "sleep stuff," smartphone apps are cheap, easy to access and make a lot of appealing promises to help improve sleep quality. If people think a $1.99 phone application will fix their sleep concerns, they will easily choose that over a visit to the doctor's office. Unfortunately, whether these apps actually work is still a matter of opinion and subject to scientific scrutiny. But some apps may help insomniacs fall asleep faster, and others might help with sleep hygiene or at least give the user a general idea about the nature of their sleep patterns.

What kinds of sleep apps are out there? What are the risks in trying these products? What's already been discussed about consumers using sleep apps?

KINDS OF APPS
Here are the main general categories of sleep apps, many of them belonging primarily to one category but often bundled with some features offered in other categories. Note: If your app requires a visual aid for you to use it, be warned that the blue spectrum light your device emits will turn off your body's natural melatonin production and delay sleep onset. Instead, use a blue-light filter on the device you are using to display the app, or wear blue-blocking eyewear, or best of all, use an app that doesn't require a visual display to work.
  • Audio relaxation apps
    These include music, white or other "colored" background noise, verbal guided meditations, vocalized hypnosis, binaural beats, isochronic tones, and other sound effects that promise to help you relax so you can fall asleep. Examples: iSleep EasyPure Sleep | AmbiScience™, Relax MelodiesSleep BugSleep SoundsSleepy Time
  • Breathing apps
    While technically not sleep apps, these programs can help induce sleep by borrowing from the breathing techniques often taught in yoga or relaxation classes. Ideally, you will learn the techniques and eventually not need to follow the prompts from the apps, but practice them as a good habit at bedtime. Examples: Breathe2Relax, Breathing ZoneUniversal Breathing: Pranayama
  • Sleep stage tracking apps
    Using various kinds of monitors, these apps claim to track vital or other biological signs in order to identify sleep staging and different elements of sleep quality. You might need to add additional wearable devices to get these to work. Examples: BedditFitBit Sleep DebtJawbone UPMotionX 24/7 (Sleep Tracker feature)Sleep BetterSleepBot, Sleep Cycle. Also: While 
    Sleepyti.me doesn't track your sleep, it does set your bedtime schedule based on your wake up time that morning.
  • Kids sleep monitoring apps
    As suggested, these help parents to keep an eye on babies and even older children while they sleep. They include some claims about sleep stage tracking technology as well. 
    Examples: Baby ConnectKids Sleep Dr., Sleep Pillow Baby Lullaby
  • Alarm clock apps
    More than just an alarm, this kind of app uses other effects with the promise that they will help you wake up more gracefully in the morning. Examples: EasyWakeUp, Morning Sun, Proactive SleepWakeApp
  • Sleep disorder diagnostic and therapeutic apps
    Perhaps the most high-tech of the bunch, and potentially the most useful, these devices can help track and record key information that could help a physician diagnose a sleep breathing disorder, a movement disorder, parasomnia or insomnia. Examples: ApneaApp, CBT-i Coach, S+, SleepRate
RISKS
The most obvious risk is that the consumer spends money on a product that doesn't work. It could be 99 cents, or it could be $99, depending upon the device, the services it might require the user to link to and any additional hardware you need to buy.

Another risk is that the devices just aren't accurate. It may seem like devices these days can do darn well anything. A laptop seems to be the device that flies the airplane anymore, and we can send text messages to someone clear around the world. Why can't sleep apps do the heavy lifting?

Ideally, it will become as simple as this. Even home sleep testing has minimized some of the more complex preparation that an overnight sleep study requires; there are fewer sensors and the patient can conduct the test at home. But even these tests are for ruling out candidates and are largely not sensitive enough to make a confident diagnosis of any sleep disorder without the aid of the higher technology used in the actual sleep lab.

It also makes sense, from the point of view of a person who works in sleep technology, that the data collection on these devices has to be somewhat limited. Most of these devices do not accurately measure brain waves, which are necessary to identify sleep stages. Heart rate monitors cannot be relied upon to validate sleep stages, though some app developers will tell you otherwise.

Most of these apps rely on a form of actigraphy, a kind of wearable or local motion sensor you use with the app while you sleep to show your activity during the night. But while these sensors notice activity, they can't discern whether the data showing waking patterns is related to apnea, the dog jumping on the bed, or the activity of a sleepwalker.

In addition, sleep apps do not really have sophisticated enough sensors to measure sleep breathing patterns and blood oxygen levels unless they are paired up with a pulse oximeter and other expensive sensors. Even then, dips in O2 saturation aren't always due to apneas, so it's hard to guess at the root cause of changes in these important sleep-related vital signs without actual observation. 

The overnight polysomnogram remains the gold standard for diagnosing sleep disorders because it includes sensors that measure body limb movement, respiratory effort, heart rate and rhythm, respiratory rate, blood oxygen saturation, eye movement, brain waves, airflow, audible recording of resistance issues and video recording of behaviors like sleepwalking or restless legs that often need to be witnessed by the human eye to be confirmed.

Finally, there's a psychological component to using sleep trackers that may have a negative impact on users' sleeping habits. Dr. Siobhan Banks, a researcher for the Sleep Health Foundation, recently suggested that sleep apps may prevent some users from getting enough sleep due to worried obsession about what the tracker is recording, not unlike the same behavior that happens with insomniacs who watch the clock all night long.

UNDER SCRUTINY
Very recently, the Journal of Clinical Sleep Medicine shared the results of a small study of smartphone users using a specific app to determine its accuracy when compared to overnight polysomnographic (PSG) data collection (aka a sleep study) ("Is There a Clinical Role For Smartphone Sleep Apps? Comparison of Sleep Cycle Detection by a Smartphone Application to Polysomnography").

Their conclusion? "Our study shows that the absolute parameters and sleep staging reported by the Sleep Time app (Azumio, Inc.) for iPhones correlate poorly with PSG. Further studies comparing app sleep-wake detection to actigraphy may help elucidate its potential clinical utility."

Equally, parents who wish to monitor their kids' sleep should be cautious before investing in the accuracy of these devices. According to a report published by Monash University headed by Dr. Sarah Biggs (Melbourne Children’s Sleep Centre), “The results of our study showed that the smartphone application did not accurately assess sleep, substantially overestimating the amount of time the child was asleep and underestimating the number of awakenings during the night."

Accuracy is no small matter. The case of inaccuracy with blood pressure measuring apps shows the kind of ethical dilemma that may also be in store for the programmers of other kinds of medical apps. BP monitoring apps are offered "for entertainment purposes only" and are not cleared as medical devices by the FDA, and yet they are still among the most downloaded and used medical apps, despite their inaccuracy. The danger in the discrepancy between a reading on a phone BP measuring app and an actual blood pressure cuff reading may be enough to endanger someone's life.

Psychology Today offers this excellent discussion ("Sleep Cycle App: Precise or Placebo?
What's the verdict on sleep-tracking apps?"--Oct 2013) reviewing sleep apps (especially those interested in tracking staging and sleep quality) to help you decide whether these are right for you. Sleep Junkies puts specific apps to the test against the gold standard of the polysomnogram in this great consumer investigation of popular sleep tracking applications; they also explain in simple terms just what needs to be measured scientifically for a sleep disorder diagnosis to be conclusive. And the American Academy of Sleep Medicine has also taken on the subject ("Smartphones for sleep: Can sleep-tracking apps improve your sleep?"), providing guidelines for those who may be turning to phone apps because they are concerned and need to identify sleep problems. 

THE FUTURE
Whether the technology is accurate or worthwhile right now is probably not as important to note as where it might be headed. More sophisticated sensors and accurate tools for helping out people with serious sleep problems is an important goal, given the problems the population has with sleep health. 

For instance, more people suffer from insomnia than from any other sleep disorder. A new app, Zziesta, holds out hope as a means for helping insomniacs reclaim their shut-eye. While it's not on the market yet, and it's safe to assume it will have "bugs" to fix once released, the promise of sleep that this app offers, like all the other apps, is encouraging. 

Like many efforts in technology, this latest trend, if appropriated by diligent sleep health promoters and held to the highest standards of evidence-based testing, could mean helping a lot more people improve their sleeping habits and feel better, which ultimately means they will live longer and have a better quality of life. 

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SleepyHeadCENTRAL strongly encourages people with ongoing sleep health problems to approach a medical professional to determine appropriate differential diagnoses and treatment. This post, like all other posts on SHC, is not intended to substitute for medical advice.

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