Seasonal Affective Disorder

The days are growing shorter naturally, and now accelerated by the end of daylight savings time, wherein the sun goes down an hour earlier. For many people this is the signal to their brains that it is time for Seasonal Affective Disorder, ironically dubbed “SAD”. Though most of us associate SAD with low mood, the disorder also encompasses episodes of abnormally high mood known as hypomania or mania. In the interest of being completely accurate, the following quote from UpToDate may be useful, “The term seasonal affective disorder (SAD) describes episodes of major depression, mania, or hypomania that regularly occur during particular seasons. The most prevalent form of SAD is winter depression, marked by recurrent episodes of unipolar depression that begin in the fall or winter and if left untreated, generally remit in the following spring or summer. Recognizing the disorder is important because SAD is common and associated with psychosocial impairment [1,2]. In addition, acute treatment is often effective and maintenance treatment can prevent future episodes.” In plain English, SAD is common, should be recognized and is usually treatable.

 Fall-winter onset SAD is also known as winter depression. Of interest, symptoms can also occur, but less frequently in the Spring, and this is known as summer depression. It is essential to recognize that all of our emotions, feelings and symptoms fall along a spectrum from very mild to quite severe. Probably the majority of people have the milder form of SAD. The DSM V attempts to characterize symptoms in a framework, but every person is unique and different. 

If you think you have SAD, I suggest taking the following basic steps or interacting with a professional counselor to assist in making the diagnosis and working out a good treatment plan. In general, the approaches to SAD can include therapy, medications, and light therapy in conjunction with attention to good sleeping, healthy eating, avoidance of excess caffeine or alcohol, and exercise.

 According to UpToDate, “sleep hygiene (table 6), including a regular sleep-wake cycle, is important for treating SAD because hypersomnia and insomnia are common in SAD. As part of sleep hygiene, creating a regular light-dark cycle may be important. Minimizing light exposure, especially blue light from computer monitors and televisions, in the late evening (e.g., during the two hours prior to the desired time of sleep onset) may facilitate sleep onset.”

 Bright light therapy – 6,000-10,000 lux (a measure of light intensity) – for 30-60 minutes a day helped 60% of patients. Evidently, morning is the best time to use the lights, but any time of day is better than not at all.

 Just for information:

 Bright midday sun – 50,000 to 100,000 lux

Cloudy day – 1000 to 5000 lux

Indoor office lighting – 500 lux

Indoor home lighting – 250 lux

Here is some information about light boxes from UpToDate. “The standard and best studied devices for administering bright light therapy are 10,000 lux light boxes that use fluorescent bulbs emitting white light. (Incandescent light poses risks to the cornea and retina.) Although light boxes emitting less than 10,000 lux can be used, longer exposures are required. Commercially available fixtures are recommended over homemade devices, due to difficulty in measuring light intensity, and to reduce electrical hazards and other risks (eg, corneal and eyelid burns) associated with poor-quality construction. In addition, patients are advised to seek light boxes designed to protect the eyes with features such as light dispersion and screens that filter out ultraviolet rays. Ultraviolet light is not necessary for the therapeutic effect of bright light therapy and should be avoided to reduce potential risks to the skin or eyes.”

Dawn simulation is an interesting twist on bright light therapy. The concept is that artificial light begins at a low level around dawn and increases in intensity (250 lux) as the person is waking up. Trials of dawn simulation showed similar positive results as bright light therapy. Termination of light exposure is timed to coincide with the patient’s habitual wakeup time.

 Of interest, of patients who benefited from taking an anti-depressant medication, some chose to take it starting 4 weeks before the usual onset of SAD and continued it for several more weeks after the return of longer days in the Spring. Other patients found it advantageous to stay on the medication year-round. These are individual decisions best made with a provider.

Seasonal affective disorder is a common and treatable malady. Recognition of this pattern is step one. If symptoms are pretty mild, I think people can try light boxes, exercise and other lifestyle interventions on their own. If the symptoms are more troublesome or the individual is not making the progress they would like to make, working with a therapist is the next step.