Sleep Deficits and Mental Health in College Students

A lack of adequate sleep is a growing public health concern, both domestically in the United States and worldwide. Additionally, the number of hours spent asleep has also decreased with technological advancement that has increased the amount of light and sound humans are exposed to daily. These effects are most pronounced on college campuses where students often stay up late to complete assignments and study for exams. Inadequate sleep has been correlated with increased risk for developing sleep disorders, psychiatric disorders, decreased cognitive performance, and increased stress.

General Statistics
Eight hours of sleep is generally regarded as being ideal for individuals who are of a college age, yet 70.6% of college students report getting less than eight hours of sleep per night. The average college students succeeds in sleeping 5.7 hours per night and pulls 2.7 all-nighters a month. As a direct result of this, 50% of college students report suffering from daytime sleepiness compared to 36% of the general population. Furthermore, 60% of college students report dragging their feet and/or feeling sleepy during class at least 3 days per week.

However, students who still get 8 or more hours of sleep per night report suffering from poor sleep quality. 60% of students, regardless of number of hours slept, report suffering from poor sleep quality and research indicates that 27% of students are at risk for at least one sleep disorder, with insomnia and hypersomnia (excessive daytime sleepiness) being the most common among college aged individuals. Additionally 41% of students report waking up at night due to the noise of others, most often a roommate.

Sleep Deprivation
Studies have shown that both partial and complete sleep deprivation are associated with cognitive and psychological dysfunction which ultimately result in reduced academic performance. College students with more nights of insufficient sleep are more likely to exhibit feelings of hopelessness, loneliness, exhaustion, anxiety, and desire to self-harm. Additionally, students are more likely to feel overwhelmed and depressed if they have more nights of insufficient sleep. Even students who manage to sleep 4-5 hours per night demonstrate significant mood dysfunction. A study in which subjects were limited to only 4.5 hours of sleep per night for week found that the participants were more stressed, angry, sad, and mentally exhausted compared to controls who slept for an adequate amount. Furthermore, the study found that after participants restored their normal sleep schedule, their mood improved dramatically. The results of this study suggest a possible causative link between insufficient sleep and depressed mood. Further studies have shown that a sleep debt of just 2 hours per night is associated with greater depressive symptoms and decreased GPA.

Sleep Disorders
Among sleep disorders, the one most commonly seen on a college campus is insomnia. Chronic insomnia is common in students, with about 9.4% of college students suffering from the disorder. Students suffering from insomnia report higher levels of obsessive-compulsive, depression, and anxiety symptomatology and report ruminating often about their sleep problems during the day. Additionally, students suffering from insomnia report ruminating about stressful daily events such as exams and reacting to such stress in a more adverse way than their peers.

Co-morbidity with Psychiatric Disorders
Insomnia is highly co-morbid with a number of psychiatric disorders. Individuals with a history of both hypersomnia and insomnia had higher rates of psychiatric disorders compared to individuals with history of only insomnia or no history of sleep disorder at all.

Major Depression
A bidirectional relationships exists between insomnia and major depressive disorder (MDD). Insomnia is a risk factor for major depression and 15-20% of patients with insomnia will go on to develop major depression. However, in 29% of insomnia cases the mood disorder preceded the diagnosis of the sleep disorder indicating that the mood disorder itself can also cause insomnia and affirming the inclusion of insomnia in the diagnostic criteria for MDD.

Psychotic Disorders
Insomnia is also common in patients with psychotic disorders, specifically schizophrenia. In particular, insomnia appears to be correlated with the cognitive symptoms and dysfunction characteristic of schizophrenia.

Anxiety Disorder
Insomnia is also common in patients with various anxiety disorders, including generalized anxiety disorder, specific phobias, and panic disorder. Insomnia can also appear in patients with separation anxiety disorder.

Substance Use Disorders
Prevalence of insomnia is higher in patients with substance use disorders such as nicotine use and alcohol use. Part of the reason for this may be that certain substances of abuse produce their effects by acting on various receptors and neurotransmitter systems in the brain that are also involved in normal sleep regulation, such as serotonin. Furthermore, insomnia has been shown to predispose individuals to substance use disorders. For example, individuals with insomnia are twice as likely to develop alcohol use problems compared to control who do not suffer from insomnia.

Attention-Deficit/Hyperactivity Disorder (ADHD)
ADHD is very weakly co-morbid with insomnia and only some children with ADHD have insomnia. Other children may be predisposed to late sleep onset but have unimpaired sleep quality. Additionally, some of the medications used to treat ADHD can cause sleep disturbances, but generally not insomnia.

Class Scheduling
The amount of sleep students get is often dictated by their first obligation of the day, such that they wake up to give themselves enough time to get ready for their first obligation. For students, this first obligation is most often the first class of the day. Studies show that delaying class start times results in fewer students self-reporting daytime sleepiness and sleepiness in class. Additionally, a positive effect on mood is evident in students who have later class start times. Finally, later start times do increase total sleep duration and actually result in bedtime being 15 minutes earlier, which is an effect that has yet to be explained.

Regularity of Sleep Schedule
One of the best ways to improve sleep quality and more importantly sleep length is by maintaining regularity in the sleep schedule. It is important to go to sleep and wake up at the same time every day whether it's a weekday or a weekend. Studies have shown that bed and rise times between weekdays and weekends often differ in a range of more than 1 to 2 hours. By scheduling classes later in the day and if possible, scheduling the same start time five days a week, a student can create a sleep schedule for themselves that will force them to wake up at the same time every day.

Darkness
The main hormone that controls sleepiness in human beings is melatonin, which is released in response to darkness. So, in order to feel sleepy enough to go to sleep it is important to reduce exposure to light late at night. Ways to reduce exposure include staying away from screens (or for some devices setting the screen to night mode) and dimming lights in the house and bedroom at least an hour before bed. By reducing light exposure in the one hour before bed, our bodies are given enough time to produce appropriate melatonin levels to induce sleepiness.

Temperature
Studies have shown that individuals who sleep in cooler rooms tend to sleep better and that many people actually sleep in bedroom's that may be too warm. The ideal temperature setting for a room in 68 *F or 18 *C, regardless of weather outside and time of year. Reducing the temperature of the room allows the body to drop its core temperature more quickly which is required for inducing sleep

Alcohol and Caffeine
Alcohol and caffeine should be avoided before sleep as well. Although alcohol is a sedative that can promote sleep, it fails to promote natural sleep and also causes increased awakenings during the night. Caffeine, a chemical widely known to induce wakefulness, can actually reduce the depth of sleep one gets if they do manage to fall asleep.

Getting out of Bed
In order to induce good sleep it is important to associate the bedroom and bed with a state of being asleep rather than a state of being awake, a process normally carried out through classical conditioning. So, the bedroom should be reserved for mostly sleeping and no other activities. Therefore, it is not advisable to lie awake in bed, rather getting out of bed and going into another room will be better for inducing sleep and preserving the association between the bed and sleep.

Napping
Although it's not a strategy for inducing sleep at nighttime, research has indicated that napping has some merits. Higher academic performers are more likely to nap during the day than lower performers. Specifically, naps in which the person falls into to slow-wave or REM sleep are especially helpful and have been shown to improve performance on certain cognitive and performance tasks. The drawback to napping, however, is that it may make it harder to go to sleep at night.