What is Seasonal Affective Disorder? What Is SAD?

Editor's Choice
Main Category: Depression
Also Included In: Psychology / Psychiatry
Article Date: 29 Feb 2012 - 1:00 PST


Seasonal Affective Disorder, also known as SAD, is a type of depression that occurs in countries that are far away from the equator during the winter months. SAD is sometimes called winter depression. As the mornings start later and evening begin earlier when winter approaches, there is less total sunlight each day. Experts say SAD is most likely caused only by lack of sunlight, and not cold temperatures. Depressive symptoms usually build up slowly as days start getting shorter, and gradually subside in early spring, as the amount of environmental sunlight each day rises.

According to the National Health Service (NHS), UK, some people may have SAD during the summer, but this is very rare.

SAD was first mentioned, in any literature we have access to today, in 1845. However, the condition did not have a clinical name until the early 1980s.

We know that seasonal variations in sunlight intensity can have an impact on what animals do, from hibernating, reproducing and seeking out a mate. These seasonal changes in sunlight affect our circadian rhythms (biological internal clocks).

According to Medilexicon's medical dictionary, Seasonal Affective Disorder is:

"A depressive mood disorder that occurs at approximately the same time year after year and spontaneously remits at the same time each year. The most common type is winter depression and it is characterized by morning hypersomnia, low energy, increased appetite, weight gain, and a craving for carbohydrates, all of which remit in the spring."

SAD is thought to affect about 7% of people in the UK, and is more common among young adults. It is more common in females than males. Approximately 8.9% of people in Alaska are believed to be affected by SAD, and 24.9% with subsyndromal SAD.

What are the signs and symptoms of SAD (seasonal affective disorder)?

A symptom is something the patient experiences and describes, such as a headache, while a sign is something other people, such as doctors and nurses, may detect, such as a rash or inflammation.

The signs and symptoms of SAD are similar to those of depression, but they typically come on as winter approaches, and gradually go away during springtime. In the majority of cases, symptoms come back each year, at around the same time. Symptoms are usually mild as autumn advances, and gradually worsen as the amount of daylight goes down. SAD severity, characteristics and patterns can vary considerably from person-to-person.

About four-fifths of SAD patients develop unipolar depression, while the rest have bipolar. Unipolar means there are persistent depressive symptoms, while bipolar involves swinging from high (manic) to very low (depressive) periods.

The signs and symptoms related to SAD include:

• A feeling of despair
• Anxiety
• Feeling guilty and worthless
• Feeling stressed
• Indecision
• Irritability
• Low moods
• Reduced libido
• Wanting to cry; crying
• Some patients may also feel sluggish and les active, they sleep more, and generally have much less energy than they normally do
• A number of SAD sufferers find themselves eating more
• The patient withdraws socially, meets friends less often, etc.
• There is often a desire for carbohydrate-rich foods, such as pasta, rice or bread
• There may be problems concentrating on things
• Weight gain

Who has a higher risk of developing SAD?

Sex - women are more likely to suffer from SAD than men. However, males tend to have more severe symptoms.

Geography - the further you live from the equator, the higher are your chances of developing SAD. Put simply, those who live in places where days are considerably shorter in winter have a higher risk of developing SAD.

Genetics - if you have a close relative who has/had SAD, your risk of having it yourself is greater

Having, or having had depression - patients with a history of depression or bipolar depression are more likely to suffer from SAD, that those with no such history.

What are the causes of SAD?

Experts are still not sure what the exact causes of SAD are. However, studies have pointed to the following:

• Circadian rhythm - our body clock. Each of us has an internal body clock which tells us when to be awake and asleep. Less sunlight in the winter is thought to disrupt our circadian rhythm, which most likely results in depressive symptoms.
• Melatonin levels - melatonin is a hormone which influences our sleep patterns and mood. Experts believe that reduced exposure to sunlight (shorter days) disrupts our melatonin balance. SAD patients produce higher amounts of serotonin during the winter months.
• Hypothalamus - it is believed that sunlight stimulates the hypothalamus, a part of the brain that controls sleep, mood and appetite - three things that have an impact on our moods. Apart from disrupting melatonin levels, lack of sunlight may also affect the production of serotonin, a neurotransmitter (brain chemical) that affects mood. People with SAD during the winter months are said to have lower serotonin levels.

How is SAD diagnosed?

The doctor may carry out a physical exam, and ask the patient some questions, which may include:

• How the patient feels (mood)
• How severe symptoms are, how long symptoms have been present, how they have progressed, and do they interfere with daily activities
• What the patient's eating patterns are
• The doctor will want to know about the patient's lifestyle
• Details on sleeping patterns, and whether they have differed recently
• Have thoughts and behavior changed as seasons change?
• Details on family history (depression, SAD, etc.)

There is no medical or laboratory test today that can diagnose SAD. The doctor may order some diagnostic tests in order to rule out any illnesses or underlying conditions. These will typically include blood tests.

There are several types of depression, therefore, diagnosing SAD accurately may take a long time.

The American Psychiatric Association (DSM-IV criteria) does not see SAD as a separate disorder, but rather a "course specifier" and may be applied as a further description to the pattern of major depressive episodes in patients either with major depressive disorder or bipolar disorder.

What are the treatment options for SAD?

According to the American Psychiatric Association (Healthy Minds), raising exposure to sunlight may help alleviate symptoms linked to SAD. Going out for long walks outdoors, for example, where there is still some sunlight outside.

NICE (National Institute for Clinical Excellence), UK, recommends that SAD treatment should be the same as for other types of depression, which involves psychosocial and/or antidepressant medications.

Bright Light Therapy If symptoms are so severe that they affect daily living, light therapy may be recommended.

Bright light therapy, also known as "light therapy" or "phototherapy", can help restore circadian rhythm and alleviate the depressive symptoms linked to SAD. Experts say this type of phototherapy also helps restore brain chemistry balance. How all this occurs nobody is sure.

The patient sits in front of a specially made light for between 30 to 90 minutes each day. Doctors say exposure in the mornings tends to give the best results.

Ask your doctor before purchasing a light therapy box. Make sure it is a high-quality one.

Psychotherapy

Although SAD involves a change the patient's brain chemistry, therapy that focuses on mood and behavior can help.

Cognitive behavioral therapy (CBT) includes a number of therapies; it is based on the idea that the patient himself/herself often created the problems. Rather than the situation being the cause of unhappiness, CBT focuses on how the patient thinks and reacts to things. If how the sufferer perceives certain situations can be altered, their behavior will change, and hopefully their unhappiness will be lessened.

CBT usually includes an individual program of self-help, another program for the patient and their partner (if necessary), and a group program (with other individuals).

Medications

The doctor may prescribe an antidepressant, usually an SSRI (serotonin reuptake inhibitor), which raises serotonin levels. Antidepressants do not work straight away; they may take from ten days to a month to work well. Patients are reminded to follow the doctor's instruction.

Experts say antidepressants for SAD are more effective if taken at the beginning of the SAD season, just before symptoms appear. Usually, they are taken daily until springtime.

Things you can do

Some people have found that making their environment sunnier and brighter helps alleviate symptoms. Examples include opening blinds and curtains, trimming the trees around the house, and sitting closer to the window during daytime.

Even during wintertime, the sun still comes up and there is more sunlight outdoors than indoors. Getting out every day for a long spell in the open air will expose you to more sunlight.

Exercise is not only good for the health, but alleviates the symptoms of anxiety and aids proper sleep. Exercises can also help people nurture a better self-image, which tends to lift moods.

Written by Christian Nordqvist
Original article date: 5 July 2004. Article re-written: 29 February 2012.
Copyright: Medical News Today
Not to be reproduced without permission of Medical News Today

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