Shedding Light On SAD

Rain, snow, unrelenting gloom, Christmas shopping, entertaining. It all adds up to holiday blues, depression and even suicide…or so the story goes.

But that’s all it is: just a story, with little basis in fact. In reality, reports of increased depression over the holidays and higher suicide rates during the winter are largely false.

In actuality, the suicide rate is lower around the Christmas holidays. Surprisingly, the peak season for suicide is in May, when spring is in full flower.

But that’s not to say that winter gloom has no effect on the human psyche. In most cases, what people call “holiday blues” is actually seasonal affective disorder, or SAD.

Because SAD is a milder form of depression, it doesn’t contribute very much to suicide statistics, but it can still be uncomfortable or can impair a person’s functioning.

There are a number of typical symptoms of SAD, including:

* Mild to moderate depression that comes every year in mid-autumn

* Excessive sleepiness and appetite, social isolation and irritability

* Symptoms of depression that are most pronounced in mid-winter

* Depression that lifts by May

* Symptoms that are not better explained by some other cause

There can be a lot of causes for depression other than the darkness of winter. Rather than diagnose yourself as suffering from SAD, it may be best to consult either your primary care physician or a mental health care provider if you experience these symptoms, especially if they’re severe.

Why do some people experience SAD? Many researchers believe the amount of light we receive through the eyes is an important factor. During the autumn and winter, we tend to get less light for a shorter time during the day. Melatonin may play a role, because its production is suppressed by light. More research needs to be done to clarify these relationships.

Regardless of the underlying mechanism, SAD affects a lot of Americans. Estimates vary between 3 percent and 6 percent of the population, with one report showing rates as high as 9 percent in Alaska. The farther away from the equator, the more common SAD seems to be. Women outnumber men when it comes to SAD, perhaps because of their greater susceptibility to depression in general. Kids can get SAD, too, with studies indicating that 2 percent to 6 percent of children aged 9 to 19 have wintertime depression.

Given the possible link between seasonal depression and fewer hours of daylight, it should come as no surprise that the most effective therapy for SAD is exposure to light. If money were no object, you could pull up stakes and move to a state, such as Florida or Arizona, with more winter sunshine. But for most SAD sufferers, whose jobs and families will keep them in northern parts of the country, so-called phototherapy &$151; exposure to bright light — is usually very effective in banishing the winter blues. In fact, studies show that up to 80 percent of SAD sufferers will get relief from phototherapy alone.

Commercially available light boxes produce 10,000 lux (a standard measure of brightness), which is about 10 times the level of light found in typical office lighting. It’s bright, but not blinding. The light boxes may be as small as a briefcase. They contain fluorescent bulbs and a filter to screen out ultraviolet light. Other models come as desktop lamps.

Generally, the lights are most effective when used in the early morning for a half hour to two hours. Don’t overuse the lamps, though, because excessive exposure to bright light will overstimulate some people, making them overactive, anxious or irritable. Another device that many find effective is the dawn simulator, which is a bedside lamp with a built-in timer that slowly increases the light level in the bedroom. Even people with relatively mild symptoms of SAD — sometimes referred to as the “winter blahs” — may perk up with the help of bright-light therapy. However, antidepressants can also be used to treat SAD, particularly in cases that don’t respond to phototherapy.

About half of all insurance plans will cover the cost of a light box, but a qualified doctor must diagnose SAD and prescribe it — which is another reason to visit your health care provider rather than engaging in self-diagnosis of SAD.

A helpful book containing more information on SAD is “Winter Blues: Seasonal Affective Disorder, What It Is, and How To Overcome It,” by Norman Rosenthal, M.D., a pioneering SAD researcher with the National Institute of Mental Health. There are a number of manufacturers of light boxes and dawn simulators on the market. To locate a dealer, submit the terms “SAD” and “light boxes” or “dawn simulator” into any Internet search engine. Your health-care provider can also provide guidance on light selection and purchase.