Friday, September 5, 2008

The elderly

Cellular ageing affects the biological clock. This explains why elderly people suffer from sleep disorders.

Elderly people tend to go to bed early and wake up early. Each case is special. Nocturnal insomnia can have drastic consequences when such people awake at night, alone and without supervision : there is the risk they might fall and sustain bone fractures (increased fragility of the bones: osteoporosis).

In the cases of such elderly people, taking sleeping tablets is contraindicated, because they diminish memory capacity, which is already deficient in many elderly patients.

Eus Van Sommeren (of the Netherlands Institute for Brain Research and VU University Medical Centre in Amsterdam) has shown in his study that many elderly people, (the majority of whom suffered from dementia), after receiving light therapy showed improvement in their dementia and in their sleep patterns.

The results of cognitive performance are comparable to those obtained with cholinergic drugs (but without the nausea).

Recommended dosage : ½ hour of light therapy using the SAD light box in the evening around 5 p.m.

Light therapy increases alertness in the evening, and this is experienced by such patients as an improvement in their general condition.

Light boxes and Jet lag

Differing time zones are experienced painfully by travellers who sometimes find themselves «leaping over» several different time zones.

Their biological clock continues to operate in sync with the place of departure, and does not synchronise with the place of arrival.

For each time zone that the traveller crosses, at least a day, or a day and a half, is considered to be necessary to recover 100% of their abilities. So after a flight from New York to Paris, a week would be necessary.

The effects vary greatly from one individual to another. For example those who sleep somewhat little tend to adapt more easily than those who sleep a great deal.

The direction of movement, from west to east or east to west (i.e. adding to or subtracting from the time of day) also has an influence on one’s adaptive faculties: it is easier to adapt to a longer day than to a shorter one.

Some additional advice :

> In the aircraft, drink at least 2 L of water (avoid alcohol and coffee).
> Regulate yourself directly to the time of day at your destination (set your watch to the destination time zone and imagine already being there. Take care however not to miss any connecting flights).
> Adapt your behaviour to the new time zone.
>In order to remain awake longer, eat food that is rich in proteins (meat).Eating proteins (meat), rich in tyrosine, containing little sugar, will increase neurotransmitter activity (serotonin) and stimulate wakefulness.
>In order to fall asleep easily, eat a carbohydrate rich meal. Eating dairy products (rich in tryptophan) and products with sugar content (which increase the insulin count) facilitates tryptophan transport through the blood-brain barrier and stimulates melatonin production.
>Upon arrival, if alertness is required, engage in sporting activities.
>Take a hot bath 2 hours before going to sleep.

Light therapy can help you to adapt to new time zones in 1 to 2 days instead of 6 to 7 days.
Each trip should be analysed individually and in « ongoing » mode.

Night shift

• Eradicate those short moments of falling asleep, and increase safety,
• get back your work motivation
• reduce the risk of making mistakes

Recommended dosage : 1/2 hour of light therapy using the SAD light box at the start of what corresponds to your working day.
In order to eliminate «sudden feelings of tiredness», ½ hour between midnight and 1 a.m.

• For workers whose rest periods vary: please consult the paragraph dealing with JETLAG.

Insomnia

Sleep is essentially driven by the circadian rhythm (24 hours) :

· Slow and deep sleep predominates in the first half of the night, whereas paradoxical/REM sleep occurs more in the second part of the night.
· In addition, sleep induction latency periods are cyclical. They depend on the time that the subject goes to bed. At 8 p.m., the wakeful period before falling asleep may exceed 50 minutes in a young person, whereas at 7 a.m., it may take less than 5 minutes for the same subject to fall asleep.
· Sleep duration also depends on the time at which one goes to sleep. It may exceed 9 hours if one goes to bed at 8 p.m., and will be shorter if one goes to bed at 7 a.m.


However, the waking/sleeping cycle also depends on homeostatic regulation (this designates the organism’s tendency to maintain constant biological parameters in the face of external change).

To take an example, after a sleepless night, the period that the subject will sleep on the following night will only be extended 10 to 12 hours. There is therefore a build up factor that takes into account “sleep debt”, or the amount of sleep that has to be caught up.

According to Dr Borderly’s model (at the beginning of the 80s), it is serotonin that responds to homeostatic factors, and melatonin that responds to circadian factors. Melatonin is produced in the epiphysis, using serotonin. Melatonin has a sleep inducing effect, as well as a hyperthermia inducing effect (i.e. it reduces body temperature).

Sleep disorders can be interpreted as a dysfunction of our biological clock.
« Phototherapy is considered to be the best non-drug treatment against insomnia ».

For people who go to sleep early and wake up early :

Recommended dosage : 1/2 hour of light therapy using the light box, in the evening (around 5 p.m.).

For people who go to sleep late and wake up late :

Recommended dosage : 1/2 hour of light therapy using the light box, in the morning (upon waking).

For an in-depth solution, correct your sleep patterns and gain 15 minutes every 3 days.
For example, you go to sleep at 3 a.m. and wake up at 11 a.m :
From day 1 to day 3 : light therapy ½ hour in the morning at 11 a.m.
From day 4 to day 6 : light therapy ½ hour in the morning at 10:45 a.m.
From day 7 to day 9: light therapy ½ hour in the morning at 10:30 a.m...

Light therapy and eating disorders

In autumn and in winter, the shorter daylight exposure time means that the brain tends to function more in the «night» mode. This results in a chemical disturbance.

The melatonin count (the night hormone produced by the pineal gland or epiphysis) increases, and has a tiring and depressive effect. At the same time serotonin (neurotransmitter produced by serotonin cells) decreases. «This explains the urge to eat sugar».

Light therapy stimulates the serotonin count. The serotonin could be combined with a hyper protein diet, which would produce the tryptophan needed for the production of serotonin.

10% of all female teenagers suffer from eating disorders. A Japanese study has shown that 40% of young women are subject to seasonal depression. The authors of this study do not explain why bulimia sufferers are so receptive to this type of depression. However, scientists do suggest that light therapy based treatment could be prescribed for all young women suffering from eating disorders. Bulimia is an eating dysfunction. The patient consumes large quantities of food (often in secret).

Dr Ray LAM of British Columbia University (Vancouver, Canada) showed that daily light therapy treatment over two weeks (30 minutes at 10 000 lux) brought about a significant reduction in bulimia. Seasonal depression also showed improvement. After four weeks the bulimia was reduced by 50%.

A study carried out by researchers at Boston University shows that light therapy can be used for bulimia or anorexia sufferers whose condition worsens in winter. These hypotheses were later confirmed.

Light therapy and non SAD

In relation with antidepressants, light therapy shortens the response time, and so brings about a much quicker and more lasting relief from depression.
And what's more, patients who continue the light therapy (after their drug treatment has ended) will notice a longer period of well-being.

Light therapy and SAD

Every year, from October to March, 10 to 15% of the population suffers from seasonal depression. The symptoms are as follows:
- depression
- melancholia,
- aggressiveness,
- lack of energy,
- bulimia,
- moody humour, …

In 2005, Light therapy was declared by the association of American psychiatrists to be the number 1 treatment against seasonal depression.

Recommended dosage : ½ hour of light therapy using the SAD light box, in the morning (preferably within 2 hours of rising).