Sleep and the Consequences of Deprivation

Sleep.  It’s something we all need and it’s something we all do.  Everyone knows that eight hours of sleep a night is all you need – or is it?  Some of us need slightly more, and some of us need less.  I fit into the former category, whereas the rest of my family fit into the latter – certainly a cause of friction from time to time.  The quality of our sleep affects our day-to-day life, as does the quantity we get and sleep deprivation can have hazardous consequences.  Those working on shifts, such as night nurses will face additional challenges.

What is sleep deprivation?

Sleep deprivation occurs when the amount of sleep achieved is insufficient to support adequate alertness, performance and health.  Acute sleep deprivation occurs over one to two days, whereas chronic deprivation occurs when an individual routinely sleeps less than what is required for optimal functioning.

Causes of sleep deprivation

Sleep deprivation occurs due to having poor quality sleep, or as a consequence of getting an insufficient amount of sleep.

• The quantity of sleep needed by an individual can be determined by the amount needed to leave the individual feeling alert the following day.
• Sleep deprivation accumulates over time, so losing half an hour each night for 4 nights will result in a 2 hour sleep deficit.
• Once normal sleep is resumed the individual will experience rebound sleep in which they have longer periods of deep sleep.

Individuals achieving an appropriate quantity of sleep may feel deprived due to experiencing disturbances in the quality of their sleep.

• The number of arousals during the night determines sleep quality, along with  the percentage, duration and type of sleep stages.
• People may be unaware of arousals from sleep during the night as they may last only a few seconds, but this is enough to cause sleep deprivation.

Consequences of sleep deprivation

The consequences of sleep deprivation vary from individual to individual, but will be quite stable within an individual.  Some individuals are better able to tolerate partial or total sleep deprivation making them more suited to working shifts.  Consequences of sleep deprivation include:

• Cognitive deficits and mental status: decreased reaction and attention times; mood that resembles anxiety and depression
• Crashes and workplace errors
• Quality of life: inappropriate drowsiness and daytime naps can impinge on people’s quality of life as they cut back on activities they enjoy
• Mortality: increased risk of mortality associated with sleep deprivation
• Cardiovascular: duration of sleep can be inversely associated with blood pressure and coronary artery calcification
• Immune function: sleep deprivation has adverse effects on immune function
• Appetite: inadequate sleep may result in excessive eating and obesity

The benefits of a good night’s sleep are pretty clear.  Those working shifts need to be extra careful that they are able to achieve appropriate quantities of good quality sleep in order to remain alert and attentive while awake.