Flip side of 'winter depression.'

Flip side of 'winter depression'

Recent studies find that the symptoms of some depressed patients are linked to the shorter daylight and extended indoor periods of the fall and winter months. Treatment with artificial bright light often dampens this type of depression (SN:3/9/85, p. 152).

But according to two psychiatrists who have treated light-sensitive patients, the disorder is more than "winter depression"; it stretches into the summer, too. While such persons generally slow down, experience depressed feelings, oversleep and overeat in the fall and winter, they become agitated, impulsive and violent and even suffer short bouts of psychosis in the spring and summer. Summer symptoms, report Peter S. Mueller and Robert K. Davies of Fair Oaks Hospital in Summit, N.J., are often brought on or made worse by treatment with the "full-spectrum" lights that ease winter symptoms.

They add that the use of "rose-gradient" glasses in the fall and winter works as well as or better than the bright lights commonly employed with these patients. Both techniques increase exposure to red-spectrum light. Spring-summer symptoms, they say, are best relieved by blue-green polarized glasses that cut exposure to long-spectrum visible light.

In the February ARCHIVES OF GENERAL PSYCHIATRY, the researchers dub the year-round disorder "seasonal energy syndrome." Of 47 patients they have studied with seasonal mood swings, 17 have been hospitalized for a total of 71 admissions. Only 20 admissions occurred between September and February. Although the patients' behavior mimics a form of manic depression, say Mueller and Davies, their symptoms, which also include migraine headaches and minor neurological problems, encompass a separate disorder.

"Winter depression" does indeed show another face in the spring and summer, responds psychiatrist Norman E. Rosenthal in the same issue, but the seasonal swings can often be diagnosed as a type of manic depression. Of 156 patients with seasonal mood changes studied by Rosenthal and his colleagues at the National Institute of Mental Health in Bethesda, Md., 90 percent have been classified as manic depressive.

The effects of looking at the world through rose-colored or blue-green polarized glasses are far from clear, adds Rosenthal. Researchers need to examine how light of different wavelengths may alter behavior at different times of the year, he asserts, while controlling for the intensity of the light transmitted and avoiding the placebo effect (improvement not due to the specific treatment). Even after demonstrating the anti-depressant effects of bright light in a number of independent samples, observes Rosenthal, "we cannot exclude the placebo effect with certainty."