Most of us will have experienced sleep deprivation. Whether you’re staying up to meet a work deadline, socialising beyond your bedtime, or you’re woken up by the kids, there aren’t many of us who get our full quota of sleep all of the time.

The occasional late night shouldn’t cause too much havoc to your health but if you consistently under sleep you may be suffering from chronic sleep deprivation, which is different. Chronic sleep deprivation can significantly impact your health. It can affect your memory and mood and it can damage your immune system and cardiovascular health at a cellular level. It can also affect your concentration and alertness, which is particularly dangerous in scenarios such as driving.

When we sleep our brains are working overtime, recovering from activity of the previous day. A study from the University of Wisconsin found that sleep increases the reproduction of cells that form myelin, which is the insulating material that’s found on the nerve cell projectors in the brain and spinal cord. The study also found that myelin is responsible for allowing electrical impulses to move from cell to cell as well as playing an important role in the body’s response to disease and infection. A lack of sleep leads to a significant reduction in the production of myelin and the overall health and effectiveness of your brain.

Dr Hassan Al Hariri, Head of Sleep Clinic and Pulmonologist, Rashid Hospital, says that a long-term sleep deprivation can cause a number of psychological issues. “It increases the risk of long-term brain cell damage and it can directly affect your mood. It can cause depression, memory-loss, anxiety, stress and other psychological issues. It can cause problems with thinking and concentration and increase the risk of accidents, as your reaction times slow.”

Long-term sleep deprivation increases the risk of brain cell damage and can directly affect your mood. It can cause depression, memory loss, anxiety [and] stress.

- Dr Hassan Al Hariri, Head of Sleep Clinic, Rashid Hospital

Initially, sleep deprivation affects short-term memory but after a longer period it can affect all cognitive function. This in turn can lead to changes in mood and increase stress and anxiety, which subsequently leads to increased blood pressure. “Between 30 and 40 per cent of cases of hypertension are stress or sleep-deprivation-related,” says Dr Hariri.

Dr Hariri says that there are often health reasons behind sleep deprivation. “Sometimes if people have low thyroid function or thyroiditis [high thyroid function] they will sleep less and become stressed. Sleep deprivation is often linked to primary medical problems,” he says. “For example, having heart problems where people start taking medication such as beta blockers, that medication may cause insomnia.”

How much is enough sleep?

While the number of hours people need to sleep varies from person-to-person and is dependent on a number of factors such as age, diet and physical activity, the most recent consensus is that people should sleep for at least seven hours each night.

“If a patient tells me that they sleep for six hours straight and that they don’t experience any disturbances in their muscles or their energy and their blood pressure is okay, then we don’t classify this as sleep deprivation. In this case the person is referred to as a short sleeper,” says Dr Hariri.

“There are short sleepers and long sleepers. When people are healthy short sleepers we don’t tell them that need to sleep more. But short sleepers should never sleep for less than five hours in general. If they sleep for less than five hours, than this can be pathological and even if a person doesn’t feel any effect it will have negative effects. They may not realise that they have a disturbance in their memory or that their mood alters. Sometimes, family members or friends recognise this more than the patient themselves.”

Terrible teens

Sleep deprivation is most commonly found in teenagers. Dr Hariri has said that some studies have shown that the figures may be as high as 90 per cent of teenagers not getting sufficient amounts of sleep. During adolescence, Dr Hariri says that teenagers requires between eight and ten hours each night. He says that many compensate for their lack of sleep during the week by resting for longer at the weekend although he believes that such behaviour can have an adverse effect on their performance and mood.

Dr Hariri says that there isn’t just a lack of awareness about sleep deprivation in teenagers but there is a general lack of awareness in the medical profession as a whole. Although the DHA is working to raise awareness he believes more still needs to be done. “I believe there should be continuous awareness programmes regarding sleep-related issues and how to assess and advise patients with sleep deprivation.”

Dr Hariri himself acknowledges that responsibilities can often hinder people’s ability to achieve their recommended quota of sleep. “For people who have to work second jobs, shifts or have to work extra hard to provide for their families – these factors can cause sleep deprivation,” he says. “We advise people in those cases to change their priorities. If you do need to work 18 hours then I would advise them to recruit additional hours for their sleep by giving up some of their other priorities such as socialising with their friends.”