Portable lamps tested to treat SAD

Fri, 18 Feb 2005 08:57:07 EST
CBC News
MONTREAL - Canadians are prone to Seasonal Affective Disorder or SAD, but new light therapies can help ward off the dark doldrums.
About three per cent of people living in northern countries get SAD every winter. The mood disorder is brought on by lack of sunlight.
It's hard to get enough light during a winter day in Winnipeg.
In people with SAD, the grey days of winter can be hard to take. Symptoms include:
-Low energy.
-Feelings of sadness.
-Poor concentration.
-Listlessness.
Light affects the production of melatonin in the body, a hormone that helps regulate our internal clocks, letting us know when to sleep or wake.
"Melatonin in the morning goes down and at night it goes up," said Dr. Hani Iskandar, director of psychiatric intensive care at Montreal's Douglas Hospital.
It's thought that people with SAD produce too much melatonin because the dark disrupts their melatonin cycles.
Patients are often treated using specially-designed lights that mimic sunlight. The intensity of phototherapy lamps is equivalent to light exposure on a sunny, spring day.
Kathy Lauer has SAD, which she said makes her feel lethargic, irritable and less sociable than normal. Lauer uses a lamp daily for at least 30 minutes, often as she sits in front of a computer checking her e-mail.
"I'm feeling better," said Lauer, who is looking forward to spring. "Not 100 per cent, but definitely feeling better."
The problem is, Lauer's job sometimes requires her to travel, and it's impractical to take the lamp on the road.
FROM DEC. 28, 2001: Light therapy comes in book form
A portable model of the lamp is now on the market, but it offers half the light intensity.
Iskandar is testing the portable version in clinical trials with his patients, to see how effective it is and for how long.
Other studies will test the lamp on night-shift workers and travellers who hope to avoid jet lag.