OT: Seasonal Affective Disorder

Seasonal Affective Disorder

If you notice periods of depression that seem to accompany seasonal changes during the year, you may suffer from seasonal affective disorder (SAD). This condition is characterized by recurrent episodes of depression – usually in late fall and winter – alternating with periods of normal or high mood the rest of the year.

Most people with SAD are women whose illness typically begins in their twenties, although men also report SAD of similar severity and have increasingly sought treatment. SAD can also occur in children and adolescents, in which case the syndrome is first suspected by parents and teachers. Many people with SAD report at least one close relative with a psychiatric condition, most frequently a severe depressive disorder (55 percent) or alcohol abuse (34 percent).

What are the patterns of SAD?

Symptoms of winter SAD usually begin in October or November and subside in March or April. Some patients begin to slump as early as August, while others remain well until January. Regardless of the time of onset, most patients don’t feel fully back to normal until early May. Depressions are usually mild to moderate, but they can be severe. Very few patients with SAD have required hospitalization, and even fewer have been treated with electroconvulsive therapy.

The usual characteristics of recurrent winter depression include oversleeping, daytime fatigue, carbohydrate craving and weight gain, although a patient does not necessarily show these symptoms. Additionally, there are the usual features of depression, especially decreased sexual interest, lethargy, hopelessness, suicidal thoughts, lack of interest in normal activities, and social withdrawal.

Light therapy, described below, is now considered the first-line treatment intervention, and if properly dosed can produce relief within days. Antidepressants may also help, and if necessary can be used in conjunction with light.

In about 1/10^th of cases, annual relapse occurs in the summer rather than winter, possibly in response to high heat and humidity. During that period, the depression is more likely to be characterized by insomnia, decreased appetite, weight loss, and agitation or anxiety. Patients with such "reverse SAD" often find relief with summer trips to cooler climates in the north. Generally, normal air conditioning is not sufficient to relieve this depression, and an antidepressant may be needed.

In still fewer cases, a patient may experience both winter and summer depressions, while feeling fine each fall and spring, around the equinoxes.

The most common characteristic of people with winter SAD is their reaction to changes in environmental light. Patients living at different latitudes note that their winter depressions are longer and more profound the farther north they live. Patients with SAD also report that their depression worsens or reappears whenever the weather is overcast at any time of the year, or if their indoor lighting is decreased.

SAD is often misdiagnosed as hypothyroidism, hypoglycemia, infectious mononucleosis, and other viral infections.

How is winter SAD treated with light?

Bright white fluorescent light has been shown to reverse the winter depressive symptoms of SAD. Early studies used expensive "full-spectrum" bulbs, but these are not especially advantageous. Bulbs with color temperatures between 3000 and 6500 degrees Kelvin all have been shown to be effective. The lower color temperatures produce "softer" white light with less visual glare, while the higher color temperatures produce a "colder" skylight hue. The lamps are encased in a box with a diffusing lens, which also filters out ultraviolet radiation. The box sits on a tabletop, preferably on a stand that raises it to eye level and above. Such an arrangement further reduces glare sensations at high intensity, and preferentially illuminates the lower half of the retina, which is rich in photoreceptors that are thought to mediate the antidepressant response. Studies show between 50% and 80% of users showing essentially complete remission of symptoms, although the treatment needs to continue throughout the difficult season in order to maintain this benefit.

There are three major dosing dimensions of light therapy, and optimum effect requires that the dose be individualized, just as for medications.

• Light intensity. The treatment uses an artificial equivalent of early morning full daylight (2500 to 10,000 lux), higher than projected by normal home light fixtures (50 to 300 lux). A light box should be capable of delivering 10,000 lux at eye level, which allows downward adjustments if necessary.
• Light duration. Daily sessions of 20 to 60 minutes may be needed. Since light intensity and duration interact, longer sessions will be needed at lower intensities. At 10,000 lux – the current standard – 30-minute sessions are most typical.
• Time of Day of exposure. The antidepressant effect, many investigators think, is mediated by light’s action on the internal circadian rhythm clock. Most patients with winter depression benefit by resetting this clock earlier, which is achieved specifically with morning light exposure. Since different people have different clock phases (early types, neutral types, late types), the optimum time of light exposure can differ greatly. The Center for Environmental Therapeutics, a professional nonprofit agency, offers an on-line questionnaire on its website, www.cet.org, which can be used to calculate a recommended treatment time individually, which is then adjusted depending on response. Long sleepers may need to wake up earlier for best effect, while short sleepers can maintain their habitual sleep-wake schedule.

Side effects of light therapy are uncommon. Some patients complain of irritability, eyestrain, headaches, or nausea. Those who have histories of hypomania in spring or summer are at risk for switching states under light therapy, in which case light dose needs to be reduced. There is no evidence for long-term adverse effects, however, and disturbances experienced during the first few exposures often disappear spontaneously. As an important precaution, patients with Bipolar I disorder – who are at risk for switching into full-blown manic episodes – need to be on a mood-stabilizing drug while using light therapy.

What should I do if I think I have SAD?

If your symptoms are mild – that is, if they don't interfere too much with your daily living, you may want to try light therapy as described above or experiment with adjusting the light in your surroundings with bright lamps and scheduling more time outdoors in winter.

If your depressive symptoms are severe enough to significantly affect your daily living, consult a mental health professional qualified to treat SAD. He or she can help you find the most appropriate treatment for you. To help you decide whether a clinical consultation is necessary, you can use the feedback on the Personalized Inventory for Depression and SAD at www.cet.org.

Reviewed by Michael Terman, Ph.D., Director, Winter Depression Program, New York State Psychiatric Institute at Columbia University Medical Center. New York City (February, 2004).

Permission is granted for this fact sheet to be reproduced, but it must include the NAMI name, logo, and contact information.

Hi Tina,
I have a condition that is remarkably similar to SAD.

My condition is called Shift workers syndrome. I used to work the midnight shift for 9 years and then afternoon shift for another 9. The result is that my circadian rhythm was thrown off horrendously. From February to October I am totally normal but from November til February I catch hell on wheels. I am currently experiencing the WORST case EVA, gettin my ass kicked and will go to the Dr. on tomorrow for HELP.

In my case, bright lights help. I also found that when I lived in a very well lit home the effects were mild. Last year I was fine but now that I live in a darkened home it is the worst ever. I've read that Alaska is by far the worst state to live in with circadian rhythm disorders and Florida is the best.

There is a medication called Nuvigil that is used to help treat circidian rythm disturbances. Some of my friends told me that it has worked wonders with them so on tomorrow I will be asking for a script. I also use sun simulating lights. They can be found at Home depot.

Teena I just bought a light on ebay. I was researching and those thangs are expensive, even some of the lights on ebay were over my budget but here is what I found for $15.00's. There are many left if you want to check them out under sunrise alarm clocks.

Here's the description:  Source Ebay

	Sunrise Alarm Light: No more ‘rude awakenings’ ever thanks to the alarm clock that wakes you with light!
	Product Highlights The first alarm clock that wakes you with light! Gently wakes you like a natural sunrise! Plus, four ‘Nature’ alarm sounds! Light intensity divided into ten levels for authentic sunrise or sunset effect! Inspired by Beijing’s famous “Water Cube," home of the 2008 world games! First ‘light’ alarm clock inspired by Beijing’s famous “Water Cube" where US Swimmer Michael Phelps won an astounding eight gold medals! You’ll wake up on the right side of bed every morning with the Sunrise Alarm Light as it gently rouses you from slumber so you can start your day feeling refreshed, alert and energized. Before your wake-up time, the light can be set to brighten up at the exact time the clock starts to ring or ahead of the alarm time by 15, 30, 45, 60, 75, or 90 minutes. You have your choice of alarms, too, with four Nature alarms: bubbling brook, lapping waves, crickets or singing birds; a standard alarm ring, or you can wake to your favorite FM radio station. In Sun Set mode, the light can be set to begin to dim anywhere from 15 to 90 minutes. The intensity of light, which is divided into ten levels, begins to dim softly and evenly at the pre-set time until it goes off. [Maximum output: 60W, life expectancy of light bulb: 1000 hours, cord length, 6-ft.]