Seasonal Affective Disorder (SAD)

Seasonal affective disorder (SAD) is a type of depression triggered by the changing of the seasons. In most cases, it occurs along with the shortening of daylight hours in the fall and continues into the winter months. SAD typically resolves with the longer days of spring and stays in remission through the summer months. Other names for SAD include "winter blues" and seasonal depression.
   
Who gets SAD?  In the U.S., approximately 5% of the population meets the diagnostic criteria for this disorder, although up to 20% of people develop some of the symptoms.  The risk of developing SAD increases with aging and affects women more commonly than men. Those living in the more northerly latitudes with longer, colder winters are also at greater risk.

What are the symptoms of SAD?  Symptoms of depression, such as sadness, feeling "empty", and loss of energy are most typical of SAD. Other SAD symptoms include:

• Feelings of hopelessness and/or helplessness
• Irritability, restlessness
• Loss of interest in activities that had previously been enjoyable
• Difficulty sleeping or oversleeping
• Overeating and weight gain 
• Trouble with concentration or memory
• Withdrawal from social situations
• In severe instances, SAD can be associated with thoughts of suicide. 

How Does SAD Develop? SAD is thought to be caused by a chemical imbalance in the brain prompted by shorter daylight hours and a lack of sunlight in the winter. Melatonin, which plays a role in sleep patterns, and serotonin, a brain chemical that affects mood, are two of the brain chemicals involved in its development. With shorter daylight hours, more melatonin and less serotonin is produced which affects the body's internal alarm clock as well as its mood.

How is SAD diagnosed?  With the overlap of symptoms of SAD and certain medical disorders, such as hypothyroidism or viral infections, a medical evaluation is recommended for those who develop features of SAD. There is no specific test for SAD but the doctor may want to perform a physical exam and blood tests to rule out possible medical disorders. When the following are present: 1) seasonal symptoms of depression for at least two consecutive years, 2) periods of depression followed by improvement when the season changed, and 3) no other life events or circumstances can be found to explain the mood changes, the diagnosis can be made on history alone.

Is there a treatment for SAD? The most common treatments for SAD are light therapy, anti-depressant medications, and psychotherapy.

• Light therapy, also called phototherapy, is an effective treatment for many people with SAD.  Phototherapy involves the use of a light box containing special fluorescent lights with a color spectrum similar to outdoor light.  Sitting in front of this artificial light source for approximately 30 minutes each day is usually adequate to modify chemicals in the brain that are responsible for the development of SAD. This is usually done in the early morning, to mimic sunrise. Studies have shown that between 50% and 80% of users improve markedly with this type of treatment. It is important, however, that treatment is continued throughout the difficult season.  Another type of light therapy involves a light placed in the bedroom that gradually increases in brightness to simulate a natural sunrise. Side effects of light therapy are uncommon with irritability, eyestrain, headaches, and nausea being reported most commonly.
   
• Antidepressant medications are also effective for treating SAD and can be used along with light therapy.  The most commonly used anti-depressants are in serotonin selective reuptake inhibitor family (SSRI) family, which includes fluoxetine (Prozac), sertraline (Zoloft), and paroxetine (Paxil).
   
• Psychotherapy is another option for treating SAD, particularly if light therapy and/or medications have not helped.  Psychotherapy appears to help by addressing negative thoughts and behaviors that are contributing to the depression rather than changing brain chemistry. 

Are lifestyle or alternative treatments effective? For those with mild symptoms of SAD, or to compliment standard treatment, a number of lifestyle measures may be considered. Whenever possible, get outside during the day for a walk. At home, open blinds or add skylights to let in sunshine. Exercise regularly for stress and anxiety relief. Remain socially active even if it requires some effort. Supplements used in treating depression, such as St. John’s wort, melatonin, and fish oil (omega-3 fatty acids), may help with SAD symptoms also.

Fact or Fiction, Wintertime Edition

See if you know the answer to these winter-related health issues, some true, some not:
   
Can a flu shot cause you to get the flu? 
A flu shot cannot cause influenza because it is either made with viruses that have been "inactivated" or with no flu vaccine viruses at all (recombinant influenza vaccine).  In a survey performed by the U.S. Centers for Disease Control, however, about a third of people who responded thought that it could. There are a number of reasons for this common misconception.  Rarely, the flu shot causes uncomfortable side effects such as fever, fatigue and muscle aches that could be interpreted as being the flu. Usually, however, the side effects are very mild, primarily consisting of soreness at the site of the injection.  A second reason for the misconception is because of the lag between receiving the shot and receiving immunity.  Since it can take up to 2 weeks for the flu shot to provide protection, it is possible that one could be exposed to the flu virus prior to the development of immunity.  Also, other viral illnesses, such as the common cold, are mistaken for the flu.  Lastly, since the flu shot is not 100% effective, it is possible that someone could contract the flu despite receiving the vaccination. A flu shot gives you the best chance for avoiding the flu, but it can't guarantee that you won't get sick.

 Is drinking alcohol and effective treatment for hypothermia? 
Despite the popular image of St. Bernard dogs carrying casks of brandy for treating avalanche victims in the Alps, alcohol is not effective for treating hypothermia.  Alcohol may feel like it warms the body, but that's because it flushes the skin with warm blood. Once the blood is at the surface of the skin, heat is rapidly lost through convection. You feel warm to touch, but at the same time, you're losing heat from your skin, so your core body temperature actually decreases.
 
Does becoming chilled cause a "cold"? 
It is commonly thought that becoming chilled can lead to a cold.  A few years ago, British researchers designed a study to look into this possibility. They took 180 volunteers, half of whom were required to immerse their feet in ice water for 20 minutes and the other half with their feet in an empty bowl.  Over the next four or five days almost a third (29 percent) of the chilled volunteers developed cold symptoms -- compared to just 9 percent in the control group.  The explanation offered by the researchers was that when colds are circulating in the community many people are mildly infected but show no symptoms. Becoming chilled causes a pronounced constriction of the blood vessels in the nose and shuts off the warm blood that supplies the white cells that fight infection.  The reduced defenses in the nose allow the virus to get stronger and common cold symptoms develop.  Although the chilled subject believes they have 'caught a cold' what is believed to have happened is that a dormant infection has become activated.  Maybe your mother was right about bundling up in the wintertime!

Does hand washing help prevent catching colds?
You bet it does, as well as helping to prevent the flu, other common viral illnesses, and food poisoning.  Hand washing is one of the simplest, easiest, and most effective public health measures. Amazingly, it is also one of the most overlooked.  Examples of when hand washing be should be done include:

• After blowing your nose, coughing, or sneezing
   
• When caring for someone who is sick or injured,
   
• After using the bathroom
   
• After touching your ears, nose, or mouth
   
• After changing diapers

Health care experts recommend scrubbing your hands vigorously for at least 15 seconds with warm soap and water; about as long as it takes to recite the alphabet. This will wash away cold viruses and many other disease-causing germs. It also will help prevent accidentally passing those germs on to others.

'Cotton kills' and other cold weather clothing wisdom

With the exception of people living in the most southerly climes, being outdoors in the winter means our relatively poorly insulated bodies will be exposed to the cold. This is where wearing the right clothing can make the difference between being protected and comfortable or vulnerable and miserable. The following common sayings related to dressing for the cold may not be completely accurate, but each contains a valuable message.

"Cotton kills" 
While this saying is somewhat of an exaggeration, cotton clothing ranks at the bottom of the list of appropriate fabrics for cold weather active wear.  With outdoor activity, perspiration is absorbed into cotton layers that are touching or near the skin. As the air pockets in the fabric fill up with water, it ceases to provide insulation. A damp layer of clothing against the skin pulls heat away from the body and can rapidly lower body temperature. Furthermore, wet, cotton clothing takes much longer to dry than comparably weighted synthetic fabrics.  Garments labeled as corduroy, denim, flannel, or duck are mostly, or entirely, made from cotton. Clothing made from synthetic fabrics or wool is more appropriate, particularly during physical activity in the cold.

"If your feet get cold, put on a hat"
The notion that the body loses more heat from the head and neck has been somewhat dispelled. Studies have shown that the rate of heat loss is essentially the same for any exposed area of the body. Since the area of the head and neck makes up approximately 10 percent of body surface area, this area accounts for a similar percentage of heat dissipation. It is still a good idea to put on a hat and scarf when outdoors in cold weather. Most people find covering the head and neck to be more comfortable when in the cold and it provides a means to ventilate quickly by removing the hat if you overheat.
 
 "Dress in layers"
There are a number of advantages to dressing in layers rather than wearing a single heavy garment.  The basic idea is that warm air is "trapped" between the layers providing more warmth to the body.  Also, it is possible to choose layers that each contribute to a "system", with special layers designed to keep the skin dry, provide insulation, and to protect us from wind and rain.  Synthetic fabrics, such as Capilene, work best as base layers, worn against the skin. These fabrics keep the skin dry by "wicking" moisture away. A middle, insulating layer of wool, synthetic fleece, or Thinsulate works by trapping air to keep you warm. Goose down is also a great insulator, but it loses almost all of its insulating properties should it become wet. The outer shell layer should be both windproof and waterproof.  Ideally, this garment also "breathes" to allow moisture to escape from the body.  Gore-Tex and Entrant are trade names of fabrics with these characteristics. Using layers of clothing also allows you to control your temperature more effectively. Should you become overheated or begin to sweat during activity or exercise, you can remove or open up a layer to ventilate. As you cool down, zip up or add a layer.
 
 "Mittens are warmer than gloves" 
To a large degree, the warmth of mittens or gloves depends on the insulating properties and thickness of the materials used in their construction. When constructed similarly, however, mittens are warmer than gloves because the extra air inside create added insulation, and because fingers maintain their warmth better when they are touching.  "Dressing in layers" can apply to the hands also. For example, a thin glove liner beneath a mid-weight glove or mitten can be warmer than a single heavy glove.  Be sure that your gloves are not too tight – constricting circulation can lead to cold hands.  If exerting yourself in cold, wet conditions, consider carrying a spare pair of gloves or mittens in the inside pocket of your jacket. This gives you a warm, dry set of hand wear to put on should your fingers become cold.

An old Norwegian saying sums it up: "there is no such thing as bad weather, just bad clothing".  Wintertime can be a wonderful time to get outside, but not if your clothing is not up to the task.  A little preparation and the right combination of clothing can make all the difference in your winter outdoor enjoyment.