The Effects of Sleep Deprivation
Adequate sleep is important for all of us to feel our best and function well during the day. But did you know that too little sleep is associated with many negative consequences including accidents, poor cognitive function and long-term health issues? How much sleep is enough? While an individual’s sleep needs can vary, in general adults require 7 to 8 hour of sleep in order to be well rested and avoid negative consequences. Adequate sleep is even more important for infants, children and adolescents and the amount of sleep needed changes with age. Newborns usually sleep 16 to 20 hours out of 24 hours with sleep and wake periods spread throughout a 24-hour period. As infants mature, their sleep need will decrease to about 13 to 15 hours with a consolidation of sleep into longer periods, with the longest sleep period occurring at night. Toddlers and preschool children need 11 to 12 hours of sleep with long periods of nocturnal sleep and 1 to 2 daytime naps. School age children usually sleep 10 to 11 hours and should not be sleepy during the day. Finally, adolescents need 9 hours of sleep, but rarely obtain that amount due to pressures from school and activities and loss of “parental control” over sleep times.
What are the manifestations of too little sleep? Many adults will yawn, feel sleepy and may even fall asleep during the day when they are sleep deprived. While some children will demonstrate sleepiness in this way, many may manifest sleepiness with poor concentration, distractibility, impulsiveness, aggressiveness and poor self control. These symptoms are similar to those noted in attention deficit hyperactivity disorder. Too little sleep can result in poorer concentration, learning and memory. Lack of sleep can also result in poorer reaction times and decreased ability to complete psychomotor tasks – the integration of cognitive function and physical movement such as that required to use precision instruments, play a musical instrument or drive a car. In fact, the National Transportation and Safety Board estimates that 100,000 motor vehicle accidents per year are related to driver fatigue resulting in 1,500 deaths and 71,000 injuries. Thus, too little sleep can result in automobile accidents and has also been linked to serious and well-known accidents such as the Challenger Explosion and the Exxon Valdez oil tanker disaster.
There are a number of health issues related to too little sleep including obesity, diabetes, hypertension, heart attacks and overall mortality. Several large studies have shown an increase in obesity in adults who sleep less than 6 to 7 hours per night with a greater chance for obesity with fewer hours of sleep. This same relationship has also been shown for children sleeping less than their age requirements for sleep. Additional studies have shown that those who sleep less than
5 hours per night have 2.5 times greater chance of developing diabetes and 2 times greater chance of developing high blood pressure. Additional studies have shown a 2 to 3 times greater chance of heart attacks in those sleeping less than 5 hours a night either chronically or intermittently. Large population studies have demonstrated a general increased chance of death from any cause in persons sleeping less than 5 hours a night.
CLIP- The National Transportation and Safety Board estimates that 100,000 motor vehicle accidents per year are related to driver fatigue resulting in 1,500 deaths and 71,000 injuries.
Too little sleep has also been linked to problems with mood and depression in children and adults. Adults with chronic sleep deprivation have been shown to have increased anxiety, depressive symptoms, overall distress and alcohol use. Middle school students with sleep deprivation have been shown to have increased problems with depressive symptoms and poor self-esteem. Teenagers with inadequate sleep have been noted to have increased behavioral problems, depressed mood, anxiety and alcohol use.
Many studies have shown poorer performance with sleep deprivation related to involuntary micro sleep periods and unstable attention. Poorer or insufficient sleep leads to decreased short-term memory, reduced learning and worsened performance with prolonged task duration. Truck drivers in a controlled study with decreased sleep were shown to have poorer reaction times and lapses in attention. One study demonstrated that a decrease in sleep of 2 hours a night led to a performance similar to that after ingestion of two to three beers! We all know we shouldn’t drink and drive, however we should also be aware that too little sleep puts us at risk when driving as well.
So what can we do about this? First be aware that too little sleep can have far reaching effects on performance, safety and health. Make sure you allow enough time for sleep, i.e. if you need 7 hours of sleep and need to get up at 6 a.m., you need to be in bed asleep by 11 p.m. Make your sleep environment conducive to sleep without distractions (no TV, bright lights or 2 a.m. snacks!) Recognize signs of sleepiness and increase your sleep time if you are experiencing such symptoms during the day. Make sure the children in your life are getting enough sleep, especially those adolescents who are driving a car. Turn off electronics at night and set up a regular calming bedtime routine to prepare everyone for sleep. If you have disrupted sleep or are tired despite adequate sleep, discuss this with your primary care provider to determine if additional evaluation is warranted.