Q: A good friend of mine recently told me that I had a kind of depression called SAD. It's true that this time of year I lose interest in doing some things and don't sleep very well, but I don't feel depressed. Could I have this problem?
-- A.L., Montreal
A: SAD is the abbreviation for seasonal affective disorder. It is a type of depression that is thought to be caused by a long-term lack of exposure to the full spectrum of light produced by the sun.
As you would expect, it is more likely to occur in the winter when the hours of daylight are shorter, curtains are drawn and you are less likely to spend time outside. It also more likely to occur in February after a couple of months of shorter days.
SAD is really a type of clinical depression. And clinical depression is one of the most challenging medical problems we face. Though there are many effective treatments for most people with depression, about half the people with clinical depression are not even detected.
There is not one symptom or lab test that can make the diagnosis. And because many people feel sad or depressed from time to time but don't have clinical depression, they and others aren't tipped off to seek help. Even if a person is seeing a doctor, many doctors have not been trained to detect clinical depression at its early stages. The average time a person spends with a doctor is often too short to pick up on the problem.
Another reason depression is often missed is that the criteria used to make the diagnosis are complex. The criteria require that a person experience at least five of nine different symptoms: loss of pleasure in life, depressed mode, sleep disturbance, appetite disturbance, loss of energy, difficulty concentrating, low self-esteem, psychological retardation or agitation and suicidal thoughts.
Fortunately, some new research may have made diagnosis easier. A recent report in the Archives of Internal Medicine showed that the four symptoms that were most predictive of depression and impairment of function were sleep disturbance, loss of pleasure, low self-esteem and appetite change.
So, paradoxically, "feeling depressed" may not be the most important symptom of depression, especially since people who are depressed often can't recognize that feeling.
There are many treatments for depression including medications, psychological therapy and, in rare cases, electroshock. Because clinical depression has at least some underlying biochemical abnormality, using a medication makes sense.
The newest class of drugs is called serotonin reuptake inhibitors and includes Prozac, Zoloft, Paxil and one introduced this year called Celexa. These medications more directly attack the underlying abnormality and cause fewer side effects than other drugs; unfortunately, they can cost 10 to 20 times as much as other medications.
Because SAD is cause by a lack of sunlight, treatment for SAD starts with spending a lot more time outside during the day or exposure to a special light source. You may also benefit from medications.
If you are concerned enough, I suggest that you take the first step by writing down the changes in your behavior over the past couple of months. Then visit a doctor, indicate that you want to determine if you are depressed and ask for a screening test for depression.
Dr. Allen Douma welcomes questions from readers. Although he cannot respond to each one individually, he will answer those of general interest in his column. Write to Dr. Douma in care of Tribune Media Services, 435 N. Michigan Ave., Suite 1400, Chicago, Ill. 60611. His e-mail address is DRFamily@aol.com.
This column is for informational and educational purposes only. It is not intended to provide medical advice or take the place of consultation with a doctor or other health-care provider.