[Stitcher]

New Light on Light Therapy
You Don't Have to be SAD to Benefit

By Syd Baumel
from The Aquarian, Winter 1998
http://www.aquarianonline.com/Wellness/Newlight.html

Daniel Kripke believes bright white light may be at least as effective an antidepressant as Prozac, Paxil, or any other drug.

That may not sound like an earthshaking revelation, but Kripke, a psychiatrist at the University of California at San Diego, is not just talking about treating the kind of depression that strikes millions every fall and winter. The veteran light researcher is talking about treating everyday, ordinary, nonseasonal depression.

Bright light therapy for the fall/winter variety of seasonal affective disorder, commonly known as SAD, was one of the most glowing success stories of the eighties and nineties. Many dozens of studies showed that it usually takes just a few days of brief exposure (typically, 20 or 30 minutes a day near a very powerful light box) to relieve most cases of this medievally dark syndrome of sloth, gluttony, and melancholy. As one expert recently editorialized in Archives of General Psychiatry, when it comes to SAD, "light is as effective as drugs, perhaps moreso." It even outshone Prozac in the latest showdown.

But even as the seeds of SAD's light cure were being sown in the eighties, Kripke and other researchers were beginning to explore other behavioural benefits of the potent biological force on such conditions as jet lag, shift work, sleep disorders, and "sundowning" in demented seniors. We now know there is a lot more to bright light therapy than just relieving SAD.

Any Seasonal Dysfunction may do

When U.S. National Institute of Mental Health psychiatrist Norman Rosenthal coined the term seasonal affective disorder in the early eighties, he had observed just one form of fall/winter dysfunction, the "affective" (mood disorder) form. But research soon revealed that not everybody who isn't themselves in the winter is off-kilter depressively.

In 1991, psychiatrists from the Albert Einstein College of Medicine in New York described a young lady who had suffered from panic attacks for seven years. "Whereas most of the year she had about one severe panic attack per week, in December and January she would have three to five such attacks daily," they wrote. A few years later, the woman also became SAD - until she received light therapy for five mornings. Her severe panic attacks dwindled to just one and her depression all but vanished in a day.

Noting a previous report of winter worsening of panic disorder in nine out of 22 patients, the New York doctors concluded in The Lancet that "seasonal panic disorder may be a variant of SAD."

"There seems to be every indication that bright light should be combined with standard therapy, except where a depressed patient might be unwilling or unable to utilize the standard treatments."~~Daniel Kripke, M.D.

Among many other variants. Research shows that other people are undermined by the fall-winter season in other ways. Some suffer just a few symptoms, typically SAD-type ones, like compulsive overeating and weight gain, difficulty getting up in the morning, or chronic fatigue. When these SAD-like symptoms are nearly "clinical," some researchers label the condition subsyndromal SAD and treat it (successfully) with bright light therapy.

For other people, the problem is a fall-winter flareup of a chronic condition like premenstrual syndrome, bulimia, obsessive/compulsive disorder, fibromyalgia, or recurrent brief depression. In a recent survey of 110 people with chronic fatigue syndrome (CFS), over a third experienced a marked deterioration during the winter months. They also scored high in SAD-like symptoms of overeating and oversleeping, and half became severely depressed, unlike the other CFSers who experienced little or no winter worsening. "Light therapy," the investigators speculated in the American Journal of Medicine, "may provide patients with CFS an effective treatment alternative or adjunct to antidepressant drugs."

Some studies - and much common sense - suggest the same could be said for any variation of the "dark season dysfunction syndrome," to coin a term. At a major Viennese SAD clinic, a patient who had endured all the "vegetative" symptoms of SAD for twenty years - but not the depression - benefited dramatically from bright light therapy. Just two weeks of morning and afternoon exposure shrank her SAD score from 17 to 1.

In Boston, a 17-year-old girl with an anorexic condition that worsened every winter enjoyed a major improvement in her depression within days of commencing light therapy. After a month, her food intake and medical status had also improved enough for the Boston University researchers to speculate that "light therapy may be a useful adjunct" for any young person whose eating disorder flares in the winter.

You Don't Have to be Seasonal

Daniel Kripke's faith in bright light as a treatment for any kind of depression is based on a substantial body of controlled clinical trials. "Light's value for nonseasonal and seasonal depression are comparable," the psychiatrist concluded at an American Psychiatric Association symposium in May, 1997. Light's net effect (the light group response minus the control group response) for the average patient had proven modest, ranging from a 12 to 35 percent symptom reduction. But this had usually taken just one week; and it was no worse than the usual net response to antidepressant drugs after two or three months, Kripke noted.

Kripke hadn't come to praise light by damning drugs. Much of the research he reviewed had combined light therapy with antidepressant drugs and/or with late-night sleep deprivation. By itself, this latter technique, which consists of getting up in the morning a few hours early, usually makes severe depressives feel much better, but only for the rest of the day. However, combined with a drug or other slow-acting antidepressant - like the amino acid tryptophan or (in theory) the herb St. John's Wort - a synergy often occurs. Improvement then is both rapid and sustained, unlike the usual lag of several weeks with drugs alone and most supplements.

At Cornell University Medical College, researchers have developed a sophisticated computer program called "MidnightSun" to advise jet-lag leary travellers on how much light - and darkness - to expose themselves to, and when, based on the timing of their flight to any one of thousands of destinations.

Kripke's trump card was that studies suggest bright light can contribute even more to this synergy, "producing an extraordinarily rapid treatment response." And, he observed, bright light synergizes psychotherapy too.

"There seems to be every indication that bright light should be combined with standard therapy," Kripke concluded his presentation (later published in the Journal of Affective Disorders), "except where a depressed patient might be unwilling or unable to utilize the standard treatments."

Unfortunately, "there's a problem with that," says Winnipeg light box designer Murray Waldman, President of Sunnex Biotechnologies. "All antidepressants are photosensitizing, and so they make the eye more sensitive to bright light." Which theoretically could court eye damage, even in users of the photosensitizing herbal antidepressant, St. John's Wort. "This is why we think our box is so wonderful," says Waldman. The Sunnex unit (see sidebar: "Let There Be Light") packs a therapeutic punch without being bright.

The Circadian Clock Counts Too

A likely reason that bright light lifts depression is its effect on the circadian clock. Light is the most powerful signal received by this tiny nerve centre in our brains (anatomically, the suprachiasmatic nucleus) that regulates the ebb and flow of our 24-hour-a-day (circadian) functions.

Depressives are notorious for being circadianly out of sync - feeling sleepy or alert, warm or cold, hungry or without appetite, at the wrong times of day or night - as if they were jet lagged several hours. Research suggests that for many depressives, the timing of bright light therapy is key, as if it were pushing or pulling their circadian clocks into sync. Indeed, for other conditions, tweaking the circadian clock is the express purpose of light therapy. Take jet lag. (Please!)

Research on the effect of strategically timed bright light - and darkness - on jet lag dates back years. A 1995 consensus report concluded that "the few field studies conducted to date have had encouraging results." At Cornell University Medical College, researchers have developed a sophisticated computer program called "MidnightSun" to advise jet-lag leary travellers on how much light - and darkness - to expose themselves to, and when, based on the timing of their flight to any one of thousands of destinations. Other experts are using timed bright light to help people adjust to extreme shift work rotations. The evidence suggests that most people assigned, say, to the dreaded midnight shift will quickly adapt if exposed to plenty of bright light on the job and shielded from it during the day (often with the help of heavy blinds - and dark goggles outdoors). Within a few days, not only will they be perky at four in the morning, but their body temperatures, appetite, hormone levels, and other circadianly regulated functions will have all joined in the circadian shift. At least if they're young. One study suggests middle-aged shiftworkers are in for a harder time.

In a controlled trial at the Hebrew Home for the Aged in San Diego, Lovell's team exposed six demented residents to two hours of bright light each morning for two ten-day periods. The residents' late afternoon and evening agitation fell by roughly 50 percent.

The same tools are being applied to adjust circadian clocks that spontaneously drift out of whack with the clocks on peoples' walls (which happens easily because, oddly, the circadian clock naturally follows a 25-hour day), either keeping people up very late at night and groggy every morning or slack-eyed in the evening and wakeful before dawn. The results are variable. For some people, well-timed doses of melatonin (a clock-setting hormone) and/or megadoses of vitamin B12 (it also works, but for reasons unknown) are proving more effective, alone or combined with timed light and darkness.

Much of this research is going on in Japan. In one study there, doctors at the National Center of Neurology and Psychiatry successfully brought a man's late to bed, late to rise sleep-wake cycle (a condition known as delayed sleep phase syndrome) into line by prescribing melatonin in the evening to send his circadian clock a "lights out" message and bright light early every morning to give it a wake-up call. Although the man stopped rising early for light therapy after leaving the hospital, he remained in sync on melatonin alone. A 31-year-old Japanese woman with the same condition responded tepidly to vitamin B12. But when morning light was added, her body clock got the message bright and clear.

Fixing Old Clocks

Some of the most compelling chronotherapeutic (chronos = time) work is being done with the elderly. With advanced age, circadian clocks seem to falter or fail just like any other organ, including (and perhaps because of) failing eyesight. The demented elderly - those with Alzheimer's or similar syndromes - appear to be the most circadianly compromised of all. And they are a prime target for bright light therapy.

"Sundowning" is the most typical circadian upset in these seniors. Sleepy and unattentive during the day, at night - even in the middle of the night - the sundowners become wakeful, restless, even rambunctious. These "nightime disruptions, wandering, and yelling are frequent reasons cited for putting a family member into skilled nursing care," note geriatric sleep researchers Barbara Lovell and her associates. Reasoning that senile deterioration of the suprachiasmatic nucleus and/or failing eyesight could be part of the problem, Lovell and other researchers around the world are studying whether daytime light therapy could compensate. The results have usually been quite positive. In a controlled trial at the Hebrew Home for the Aged in San Diego, Lovell's team exposed six demented residents to two hours of bright light each morning for two ten-day periods. The residents' late afternoon and evening agitation fell by roughly 50 percent. The three most severely agitated seniors were especially responsive, though some of the mildly agitated residents actually worsened slightly.

A possibility that seems not yet to have been explored is that bright light may be an appetite supressant for carbohydrate cravers, bingers, or bulimics who are light deprived any time of year.

In Japan, early morning bright light helped a demented nursing home resident sleep more soundly for six months. Withdrawing the therapy re-upset her peaceful slumber; resuming it restored the benefits. In an instructive study from Amsterdam, researchers spiked daytime living room light levels for four weeks in the homes of 22 demented subjects. Only those subjects with intact vision enjoyed a stabilisation of their rest/activity cycles.

In the healthy elderly, a pattern roughly opposite to sundowning is more typical: fighting to stay awake and alert through the evening, then tossing and turning early in the morning. But, as experts from the Laboratory of Human Chronobiology at New York Hospital caution, the usual prescription - sleeping pills - also puts these fragile insomniacs at increased risk for nightime falls. In contrast, timed bright light exposure, these experts conclude in a consensus report, shows strong, if so far limited, evidence of being a safe and effective alternative.

For elderly (or young) people who get sleepy too early in the evening, evening light is the circadian prescription (but see the cautions in the sidebar, "Let There Be Dark"). People with a more sundowning-like circadian disturbance respond better to morning light. In general, it would seem that the brighter the day, the sounder the night's sleep. Thus, in a controlled three and a half month study, brightening the day made sixteen elderly insomniacs act "brighter" during the day - and sleep more soundly at night. Similarly, in a nongeriatric study from Vienna, a strong dose of daytime bright light relieved the insomnia of withdrawing alcoholics. And in Russia, bright light therapy improved the sleep of patients with fibromyalgia.

From PMS to Parkinson's

More uses for light therapy surely await discovery.

• In preliminary studies, bright light has relieved premenstrual syndrome, though very dim red light has worked just as well for this highly placebo-responsive condition.
• In other preliminary work from Russia, the light cure was deemed extremely helpful for people with Parkinson's disease. This makes sense, because bright light stimulates two neurotransmitters that Parkinson's sufferers lack: serotonin and dopamine.
• One of the most tantalizing possibilities is that, just as bright light usually slays the cookie monster for people with winter depression, it might also help nonseasonal carbohydrate cravers, bingers, and bulimics. But so far, the research has been less than enlightening. In a study from the Department of Psychiatry at the University of British Columbia, bright light therapy during the winter relieved the symptoms of both seasonal and nonseasonal bulimics significantly more than the dim light placebo. However, the seasonal bulimics responded much better. In a subsequent, evidently non-winter study from Ottawa Civic Hospital, while bright light lowered depression more than normal indoor light in bulimics, it had no significant effect on their eating.
• A possibility that seems not yet to have been explored is that bright light may be an appetite supressant for carbohydrate cravers, bingers, or bulimics who are light deprived any time of year. Perhaps the same could be said for any symptoms associated with a low light lifestyle.

One thing seems certain: The shiniest force in nature has more than just a few medical applications up its sleeve.

[wendy s]

Light certainly makes a difference for me. If I get enough exercise in the daylight, preferably sunshine, then I sleep a lot better. And of course, if I get enough exercise and sleep, I generally feel a lot better. I have daylight light bulbs in my bathroom to try to help with short winter days

I've tried melatonin lately, and with 9 mg. at bedtime at 10:00, I have a less restless sleep. I started with one 3 mg. tablet at 8:00 as my naturopath advised, but 9 mg. at bedtime works better for me. I'm going to try taking another 3 mg. tablet the first time I wake up at night - it used to be 11:30, and now it's closer to 1:30 or 2:00 - and see if that lets me sleep past 5:00.

I'm glad you're feeling well enough to post all this interesting information again, Carolyn. Hope things are going well.

[sunflower4u]

Wendy,
I take 3 mg of melatonin but it is '6-8 hour time release' and even if I wake during the night have no problem going back to sleep. I usually take it about 1/2 hr. before bedtime. Works well and sleep was a problem for me as well. I feel rested in the morning and usually get 8 hr. of sleep a night.
Also use a light in the winter.
Sunflower

[reverett123]

Get it? "sleeper?" Get it?

OK, so they can't all be great ones. But circadian rhythms run the whole show. It has recently been discovered that every cell in the body has a clock just vibrating away and each of those clocks is synchronized by a master clock in the brain. The master clock, in turn, is set by light.

I notice that if I get up at 2:00 AM my functioning is a lot worse than if I get up at 4:00 AM. I really don't think that it is just a matter of dopamine production but also a matter of receptor sensitivity and also cortisol rhythms.