Uriel Halbreich, professor of psychiatry and gynecology and obstetrics, is director of biobehavioral research at UB and an international expert in psychopharmacology, hormonal disorders and behavior, with special interest in premenstrual syndrome, cognitive disorders and depression.

	Halbreich

How common is depression?

Depression is very prevalent, with up to one of four people having severe depression that would necessitate treatment at least once in their life. Many sufferers have a chronic disorder with repeated episodes. A comprehensive study conducted by the World Bank, the World Health Organization (WHO) and the Harvard School of Public Health found that in 1990, Major Depressive Disorders (MDD) was the fourth most burdensome disorder among hundreds of disorders worldwide. The number of human productive years lost to depression is staggering. Depression is not a homogenous disorder; there are various kinds of depressions. But what most depressions have in common is that up to 90 percent are treatable. A consequence of not adequately treating depressions might be disastrous. Many people do not realize that depression is a disease that may lead to mortality-quite a number of severely depressed patients commit suicide.

Can you describe the different types of depression?

The main types of affective disorders are MDD, which consists of some subtypes like psychotic depression and postpartum depression; manic-depressive disorder, also known as bipolar disorder (B-D); reproduction-related dysphoria found mostly in women, like premenstrual (PMS) dysphoria, and Seasonal Affective Disorder (SAD).

Is there any link between depression and the weather?

We have to distinguish between clinical depression-severe depression that is debilitating and calls for medical intervention-and "normal" fluctuation in mood. Our mood changes in response to external, as well as internal, stimuli. We are cheered up by the good and become gloomy in response to the bad. We all like to bask in the sun, and gloomy weather, indeed, may dampen one's mood. But this does not, and should not, push us to run for psychiatric help. During the winter, normal people feel down or irritable more easily, some drink and complain more. However, people who suffer from MDD do not necessarily have more episodes during the winter. The number of severe depressive episodes is equal during the winter and the summer. However, there is a seasonal variability in severity and number of episodes of major depression, as well as manic-depressive disorder, during the fall and spring. The most severe episodes occur during the spring; that is when the rate of suicide is the highest.

Are people in upstate New York more depressed than those living in the Sun Belt?

The prevalence of MDD is similar all over the world. Epidemiological studies performed in the U.S. showed a uniform geographical spread of that disease. People in the Northeast have no more severe depression-or clinical depression-than people in the Sun Belt. So Buffalonians probably are no more depressed than their cousins in Miami.

What is SAD?

SAD appears during fall and spring and, as opposed to MDD or bipolar disorder, appears only during these periods of change.

What are the symptoms?

People with SAD have low energy, sleep more, eat more, are anxious, become irritated more easily, are very sensitive to minor negative stimuli. They usually want to be alone but once they are dragged out for entertainment, they enjoy it. The capacity to enjoy distinguishes people with SAD from many people with MDD, in which one of the characteristics is anhedonia, or the inability to enjoy. MDD also is associated with guilt feelings, less sleep, decreased appetite, somatic complaints and diurnal variability in severity of symptoms, as well as cognitive impairment-all symptoms that usually are not experienced by people with SAD.

What causes SAD?

SAD probably is caused by the change in the light-dark ratio; it is more apparent when the change is the most rapid-during fall and spring-though probably because of other factors, it is more prevalent during the fall. Temperature fluctuations contribute to severity. Constant darkness or cold weather do not necessarily cause SAD.

Why are many people more interested in SAD during January and February?

During the holidays, people with good social support are busy and happy, and mildly severe depressions are more tolerable. Lonely people are acutely aware of their problems, but do not necessarily become more clinically depressed. Following the holidays, the "happy rush" is over and we face reality. If you add to it the gloomy weather and the credit-card bills, there are many reasons to complain. And "cabin fever?" Do you really believe that people in Buffalo are trapped in their "cabins" for the winter? I am not so sure that even before the modern era, when farmers stayed inside their cabins more during the winter, that depression was more prevalent. Drinking, irritability, family intolerance and violence? Probably yes? Depression? Probably not!

Do we have to go to the Caribbean to treat SAD?

That would be nice, but medical-insurance companies would not reimburse for it! There are two main treatment modalities for SAD. One is light therapy, which consists of being exposed to bright sun-like light early in the morning and sometimes also during the evening hours. The idea is bi-fold: to counteract the change in light-dark patterns and to synchronize the light period to light-dark rhythm of the individual's own internal diurnal rhythm. Another treatment modality is the prescription of serotonergic agonists antidepressants, whose spectrum of efficacy is broader.

Is there anything else you'd like to add?