SEATTLE -- Teens and young adults who are heavy users of social media are more likely to have sleep habits that go against all recommendations, but whether there is a causal connection -- and in which direction -- has yet to be established, according to several studies reported here.
For example:
- Among 473 Philadelphia-area residents in their 20s, nearly all kept a mobile device near their beds and most reported using them for calls, texts, emails, or Internet functions in bed at least occasionally.
- Arkansas college students who said they made a point of checking their social media during their ostensible sleep time were significantly more likely to self-report daytime sleepiness, use of sleep medications, and impaired cognition.
- University of Texas students who said they used social media frequently were significantly more likely to show signs of sleep and mood disorders.
- Harvard students with irregular sleep patterns had lower grade-point averages than those whose sleep times were relatively invariant.
Action Points
- Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
These and other studies were reported here at SLEEP 2015, the annual conference of the Associated Professional Sleep Societies. But none of them were able to show that the participants' attachment to social media was driving their poor sleep hygiene.
Michael Grandner, PhD, of the University of Pennsylvania, who presented the Philadelphia survey data, acknowledged that the respondents who used their devices in bed may have done so to fill the time when they were already awake for other reasons. (On the other hand, he pointed to one respondent who reported being awakened nearly every night by incoming phone calls -- but who persisted in keeping the phone by the bed.)
Current recommendations, released earlier this month by the American Academy of Sleep Medicine and the Sleep Research Society, are that adults get at least 7 hours of relatively uninterrupted sleep each night; teens and young adults should get 8-10 hours, with more than 9 hours "appropriate" in this age group. National survey data, though, show that mean sleep duration among 18-year-olds is just over 7 hours. These and other data indicate that, as teens progress through their adolescent years, their average sleep duration falls by about 10 minutes each year.
These statistics are often offered as evidence that adolescents' social habits and school schedules are cutting into needed sleep time. But some researchers are questioning whether that is really the case.
Ian Campbell, PhD, of the University of California Davis sleep laboratory, reported data here indicating that the decline in sleep time may actually reflect "normal brain maturation." Sleep EEG studies in his lab have indicated that nearly all of the decreased sleep time is in non-REM sleep; the amount of REM sleep that adolescents in these studies get remains essentially unchanged.
"That's not what you would expect from sleep restriction," Campbell said. Usually when people are getting less sleep than they want or need, he explained, they show reductions in both REM and non-REM sleep. Other characteristics of the study participants' EEG patterns were also consistent with a progressively more adult-like sleep architecture as they got older, he said.
Highly Variable Sleep Patterns
The Harvard study showed that a substantial minority of college students maintain sleep schedules that border on the bizarre. Charles Czeisler, MD, PhD, reported findings from a study of 61 undergraduates, who completed sleep diaries twice daily for a month. The patterns were then quantified with a Sleep Regularity Index, which provided a numerical grade for the consistency of both sleep duration and the daily timing of sleep.
Findings from the top and bottom quintiles of this index were the focus of Czeisler's talk. Those at the top went to bed and got up at nearly identical times each day; those at the bottom showed wild variations from one day to the next. He noted one participant who took only brief naps at seemingly random times over a 3-day period, totalling only a few hours of sleep during that time, and then slept soundly for 8 hours on the fourth day.
But other factors also correlated with sleep regularity, Czeisler said. In particular, the circadian cycle in the highly irregular group was delayed about 3 hours compared with the most regular group. The irregulars tended to be awake later into the night and were out of bed for the day later as well.
And, the mean grade-point average for the irregulars was 3.42, versus 3.72 (P<0.05) for the most regular quintile.
Sleep regularity was also examined in a study by Yelena Blank, PhD, and Richard Bootzin, PhD, of the University of Arizona, involving 311 college freshmen (two-thirds female). The researchers looked for associations with mood and emotional parameters, and found them.
Specifically, they found that more regular sleep correlated significantly with better mood (r=0.23, P<0.001), with fewer sleep complaints (r=-0.24, P<0.001), and with greater use of a healthy "reappraisal" coping strategy for dealing with emotional issues (r=0.28, P<0.001). However, there was no association between sleep regularity and use of (unhealthy) emotional suppression, Blank said.
In both studies there was no marked difference in total sleep duration between regular and irregular sleepers.
Social Media: Driver or Epiphenomenon?
Neither of these groups asked participants about mobile device or social media use, but this was covered in other studies presented here.
Grandner and colleagues analyzed a portion of survey data they had collected on about 1,000 people in the Philadelphia area from young adults into middle age. For the current analysis, they focused on 473 respondents age 22-29, on the assumption that social media would be especially prominent in their lives.
The survey included questions about a number of behaviors related to mobile device use in bed -- for example, asking if they made phone calls or sent emails while in bed, whether they browse the Internet, whether they checked their phones immediately on waking, and whether they experience unplanned awakenings from the device (such as by audible alerts for incoming calls or text messages). The survey also asked the frequency of such events. In addition, participants were asked about sleep duration and symptoms that might reflect sleep disorders such as apnea.
Not surprisingly, heavy use of devices was associated with a number of adverse outcomes, including short sleep duration and poor sleep quality. The most deleterious activities appeared to be frequent awakenings from the device and, especially, checking the devices frequently while in bed. The latter accompanied nearly every adverse effect considered in the study, including moderate to severe insomnia, daytime sleepiness, and risk for sleep apnea.
But Grandner stopped short of blaming the devices or their functions for the sleep problems in the study. He noted that participants weren't asked why they were using the devices in bed, and said it was plausible that the heavy users were people which chronic sleep problems, who used the awake time to stay in touch with friends and family.
The issue of "why" was addressed, at least informally, in a study reported by Patricia Carter, PhD, RN, of the University of Texas in Austin, where she and colleagues had studied 149 mostly female students. Nearly all said they used social media daily including Facebook, Twitter, Instagram, and Pinterest.
Participants were asked why they use social media; a common theme, Carter said, was maintaining connections with distant family and friends. Most participants were freshmen or sophomores, who would be vulnerable to homesickness, she said.
More rigorously, participants completed the sleep domain portion of the PROMIS health status evaluation and the CES-D screening form for depression.
Scores on both instruments indicating poor sleep quality and depression symptoms, respectively, were significantly (P<0.01) correlated with self-reported frequent use of social media, Carter said. Social media use was also significantly associated with later sleep onset.
Findings were similar in a study by University of Arkansas psychology professor David Mastin, PhD, and colleagues. They administered a variety of sleep assessments to 436 undergrads along with items on general mental status and two specific questions about social media use:
- "I wake up early or during the night to check or respond to social technology"
- "I check e-mail, texts or social media during my sleep time"
"Yes" answers to one or the other of these questions were significantly associated with sleep parameters and adverse mental status. Among the latter: long sleep latency, shorter duration, use of sleep medications, poorer sleep efficiency, daytime sleepiness, preoccupation with sleep, decreased motivation, mood disturbance, and impaired cognition.
But the survey-based designs of most of these studies preclude any conclusions of cause-and-effect. Perhaps social media technologies do keep users out of bed; but if one already is having trouble sleeping, Facebook and Snapchat are a handy way to pass the time.
Aside from the obvious limitation of self-reported data in all of these studies, another was that an important social technology -- online gaming -- was not considered in any of them. Also, most of the participants in these studies were women. These two issues limit the generalizability of the findings, particularly since the online gaming demographic skews heavily toward males.