Sleep deprivation

What is sleep deprivation?

Sleep deprivation is a condition characterised by inadequate or insufficient sleep sustained over a period of time. It occurs when an individual consistently fails to obtain the amount of sleep that they need. About one-third of the Australians are thought to be sleep deprived. Sleep is a vital physiological process that allows the body and brain to rest, recover and perform essential functions including memory consolidation, emotional regulation, immune function and general health maintenance. Sleep deprivation can lead to poor short-term and long-term health outcomes as well as impair everyday functioning.

How much sleep is enough?

The amount of sleep you require varies depending on your age and individual needs. The Sleep Health Foundation recommends 9-11 hours for school age children, 8-10 for teens, 7-9 for adults aged 18-64 and 7-8 for older adults (65 and over). Whilst these hours are recommended, adults who are receiving slightly more or less may still be achieving healthy and adequate sleep.

Some people can cope very well with much less and some need much more every night. We now believe that many aspects of sleep are genetically determined, with the identification of a gene that makes some people cope more easily with a lack of sleep.

Supplementing with napping during the day of up to 30 minutes can help achieve recommended hours of sleep and has been demonstrated to alleviate cognitive deficits associated with sleep deprivation. However, a sudden increase in napping or lots of napping may be indicative of an underlying health condition or sleep deprivation itself and can also impact the ability to get to sleep at night.

Causes of sleep deprivation

There are many factors that can cause individuals to sleep at shorter intervals but it is also important to consider the quality of sleep and not just the total number of hours as poor quality sleep can also result in sleep deprivation. Factors that impair the quality of sleep include things that wake a person up, prevent falling asleep and things that disrupt normal sleep cycling to occur.

Lifestyle behaviours:

• Voluntary choices that reduce time available for sleep and having inconsistent bed and wake times
• Use of electronic devices late at night.

Sleeping Environment:

• An uncomfortable sleeping environment. Environmental factors such as heat or cold as well as noise can have a major impact on the quality and consistency of sleep.

Work:

• Shift work (working outside of the traditional nine-to-five day) can lead to sleep deprivation. Shift work can alter our natural circadian rhythms (our biological clock that regulates alertness and sleepiness, hunger, temperature and hormone levels).

Sleep Disorders:

• Obstructive Sleep aponea, nasal congestion or snoring, for example, individuals can stop or limit their breathing during sleep. This can cause a person to wake or interrupt their normal sleep cycle.
• Insomnia. Insomnia causes problems in initiating and maintain sleep throughout the night
• Restless Leg Syndrome
• Bruxism (grinding your teeth).

Other medical conditions:

• Chronic pain can disrupt sleep
• Mental health (e.g., anxiety and depressive disorders). These can be highly co-morbid with sleep problems
• Nocturia - Waking up multiple times during the night to get out of bed to urinate. This can disrupt normal sleep patterns
• Diabetes. Fluctuating blood glucose levels can disrupt sleep
• Substance abuse. medication, alcohol, illicit substances and addiction.

Symptoms of Sleep Deprivation

Changes in the way you sleep:

• Falling asleep when not intending to (e.g. reading the newspaper, watching TV
• Falling asleep quickly when going to bed
• Sleeping long hours on the weekend
• Taking naps
• Changes in the way you feel:
• Feeling fatigued or lethargic throughout the day, yawning frequently
• Feeling irritable
• Change in mood including feeling depressed, anxious, stressed, paranoid or experiencing suicidal thoughts
• Low motivation
• Feeling less interested in sex
• Experience of psychosis: sleep deprivation induced psychosis can involve changes in perception of reality, including disorganised thoughts, speech and delusions or hallucinations.

Changes in how you think and move:

• Having difficulty concentrating
• Having trouble remembering things
• Processing information at a slower pace
• Poor balance and coordination
• Increased appetite, especially for calorie dense foods
• Craving (more) caffeine.

Effects of Sleep Deprivation

Sleep deprivation can impact your body in many ways. Sleep is essential in healthy immune function, brain function, hormone regulation, metabolic function blood pressure regulation and heart function.

Impact on your brain

Insufficient sleep can impact your brain’s functioning including your ability to remember, regulate emotion and attention, the speed you process information and the ability to have insight. Even short-term sleep deprivation can impair these functions.

In particular, sleep plays a key role in memory formation and consolidation.

Sleep is vitally important for flushing out toxic waste products that build up in your brain during the day. Accumulation of these toxic proteins are involved in the development of Alzheimer’s Disease. Sleep deprivation is associated with increased risk of both cognitive decline and dementia.

Sleep deprivation is also highly co-morbid with mental health disorders such as anxiety and depression. Sleep is closely connected to emotional regulation. The relationship between sleep deprivation and mental health disorders seem to be bi-directional. That is, mental health disorders can make it difficult to sleep, at the same time poor sleep can contribute factor to the initiation and/or worsening of mental health problems.

Risk of chronic conditions

Sleep is involved in regulation of blood pressure, cholesterol and blood sugar levels. Sleep can also impact our diet and physical activity levels. When we don’t get enough sleep our bodies can crave energy-dense foods that are rich in fats and carbohydrates. We also experience fatigue and sleepiness during the day which can reduce our motivation to exercise and impair our performance when we do exercise.

Sleep deprivation is associated with increased risk of cardiometabolic conditions including obesity, hypercholesterolaemia (high cholesterol levels), diabetes and hypertension. Having short sleep durations, particularly less than 7 hours per night is associated with increased risk of cardiovascular disease morbidity and mortality.

Impact on immune health

Sleep and the immune system are closely connected. During sleep there is an increase in important proteins involved in immune function and inflammation (e.g., cytokines). Immune regulation during sleep may help with recovery and repair of wounds or fight off an infection. Consistent sleep can strengthen the immune response supporting a well-balanced immune defence system. This means that good sleep supports a more efficient response to vaccines and less server allergic reactions.

Long-term sleep deprivation can negatively impact your immune response can enhance susceptibility to infections and a reduced immune response to vaccination. Sleep deprivation is thought to lead to a persistent low-grade inflammation, and also produce immunodeficiency, which both have detrimental effects on health.

Healthy Sleep Recommendations

When you feel that you are not getting the sleep that you need, there are some things that you can do to improve your sleep.

• Prioritise your sleep: Due to lifestyle choices, leisure activities, and other obligations we sometimes do not prioritise our sleep.
• Bed and wake times: Go to bed and wake up at the same times each day, even on weekends ensuring you get enough sleep. This will help with maintain a good circadian rhythm (the biological clock that dictates multiple processes in the body, including alertness and sleepiness).
• Time allocated to sleep: Make sure you allow enough time obtain the full amount of sleep you need for each night.
• Bedtime routine: Maintain a quiet, steady bedtime routine. This will put you in the right frame of mind to sleep.
• Sleeping environment: If it is possible, have a comfortable bedroom environment (e.g., comfortable bedding and pillow and room temperature and quiet and dark as possible).
• Sunlight: Getting frequent sunlight exposure during the day supports a healthy circadian rhythm that helps you be alert during the day and sleepy at night.
• Physical activity: Try to engage in regular physical activity. Physical activity can improve your sleep quality at night and contribute to a normal sleep schedule.
• Avoid things that will disrupt your sleep
• Alcohol: While drinking alcohol may make some people sleepy, consuming alcohol before bed can result in a poor quality sleep.
• Napping: Napping frequently and more that 30 minutes per day. Avoid napping in the late afternoon or evening. Napping frequently and longer than 30 minutes can reduce your sleep duration at night and result in a disrupted night’s sleep.
• Caffeine: Consuming caffeine before bedtime. High doses of caffeine can remain in your body system for hours and make it harder to fall and stay asleep. Some people are more sensitive to the effects of caffeine and may need to avoid consumption of caffeine after lunch to improve sleep.
• Electronic devices: Use of electronic devices at night (e.g. TVs, smartphones, tablets, computers). Blue light emitted from electronic devices can interfere with melatonin levels, a hormone that makes you feel sleepy at night-time and is essential for regulation of day/night sleep patterns.

For further healthy sleep recommendations refer to the Sleep Health Foundation website. This is Australia’s leading advocate for healthy sleep and provides evidence-based recommendations.

Where to get help

• Your GP (doctor)
• Sleep health foundation
• Sleep disorder clinic / sleep specialist - a sleep specialist is a medical doctor who has undertaken specialised training in the field of sleep medicine.
• Psychologist - Some psychologists are trained in therapies to improve sleep, particularly insomnia, using evidence-based treatments such as Cognitive Behavioural Therapy for Insomnia (CBT-I) and Mindfulness-Based therapies.