By Sol Inés Peca
The days may be getting longer and spring may have started, but it still looks and feels like winter and for many, SAD (Seasonal Affective Disorder) still lingers with every overcast, chilly morning and periodic wet snowfall. Being SAD is not just feeling blue though.
“Many people feel mildly depressed during winter, but some people have more severe bouts of feeling down all the time,” says Dr. Hani Iskandar, Medical Chief of the Intensive Care Unit, Emergency, Brief Intervention Unit and Electroconvulsive Therapy Unit at the Douglas Institute. “They experience low energy, problems with sleep and appetite, loss of interest and reduced concentration to the point where they have difficulty functioning at work or in the home.”
Other symptoms of SAD include oversleeping, extreme fatigue, increased appetite with carbohydrate cravings, overeating and weight gain. With more severe episodes, people may have suicidal thoughts.
At the Douglas Institute, Iskandar, who is also Associate Professor at the Department of Psychiatry at McGill University, leads a team treating patients with SAD using light therapy. “Research shows that light has a biological effect on brain chemical (neurotransmitters) and function,” says Iskandar. “Research has also shown that many patients with SAD improve with exposure to bright, artificial light, called light therapy, or phototherapy.”
Starting out as a psychiatry resident at McGill University in 1982, Iskandar has become a prominent expert in treatment-resistant mood disorders and seasonal depression. “I started to be more interested in light therapy and its use in affective disorders after my residency supervisor asked me to help with research on melatonin change during the winter months,” recalls Iskandar. “Because melatonin is a hormone affected by light, I started to treat patients suffering from seasonal affective disorder with light.”
The use of light to treat medical disorders is nothing new. During the dawn of Western medicine, its father Hippocrates is known to have encouraged the use of sunlight to treat various diseases, a practice known as heliotherapy. Currently, light therapy is studied and used beyond SAD in the treatment of a variety of disorders, including major depression, West-to-East jet lag, delayed sleep phase syndrome, shift work and premenstrual syndrome.
So how does light therapy work? “A fluorescent light box is the best studied light therapy treatment,” explains Iskandar. The light box radiates special bright fluorescent light, with filters to block the harmful ultraviolet rays. Lux is the measurement of light intensity and a cloudy day is about 3,000 lux; a sunny day is 50,000 lux or more. Regular indoor light is less than 400 lux.
“Patients usually purchase a light box and use it in their homes, with a dose of 10,000 lux,” adds Iskandar. “As little as 30 minutes a day of sitting under the light box results in significant improvement in 60% to 70% of SAD patients.”
Iskandar recommends that people with certain medical conditions, such as retinal disease or diabetes, or people taking certain medications should have a special eye exam before considering light therapy.
Iskandar himself uses the light box from December to March. “I am originally from Egypt – a very sunny country,” says Iskandar, who has now lived through over thirty long Canadian winters. “Montreal winters are hard, and even more so because of the lack of light,” he adds.
With snow still on the ground and cold temperatures prevailing, effects of SAD could extend well past March. But some respite might not be that far off. “The effect of light therapy is through the eyes, not through skin exposure,” explains Iskandar. “Improvement is usually noticed by the third day.”
By Sol Inés PecaThe days may be getting longer and spring may have started, but it still looks and feels like winter and for many, SAD (Seasonal Affective Disorder) still lingers with every overcast, chilly morning and periodic wet snowfall. Being SAD is not just feeling blue though.
Other symptoms of SAD include oversleeping, extreme fatigue, increased appetite with carbohydrate cravings, overeating and weight gain. With more severe episodes, people may have suicidal thoughts.
At the Douglas Institute, Iskandar, who is also Associate Professor at the Department of Psychiatry at McGill University, leads a team treating patients with SAD using light therapy. “Research shows that light has a biological effect on brain chemical (neurotransmitters) and function,” says Iskandar. “Research has also shown that many patients with SAD improve with exposure to bright, artificial light, called light therapy, or phototherapy.”
Starting out as a psychiatry resident at McGill University in 1982, Iskandar has become a prominent expert in treatment-resistant mood disorders and seasonal depression. “I started to be more interested in light therapy and its use in affective disorders after my residency supervisor asked me to help with research on melatonin change during the winter months,” recalls Iskandar. “Because melatonin is a hormone affected by light, I started to treat patients suffering from seasonal affective disorder with light.”
The use of light to treat medical disorders is nothing new. During the dawn of Western medicine, its father Hippocrates is known to have encouraged the use of sunlight to treat various diseases, a practice known as heliotherapy. Currently, light therapy is studied and used beyond SAD in the treatment of a variety of disorders, including major depression, West-to-East jet lag, delayed sleep phase syndrome, shift work and premenstrual syndrome.
So how does light therapy work? “A fluorescent light box is the best studied light therapy treatment,” explains Iskandar. The light box radiates special bright fluorescent light, with filters to block the harmful ultraviolet rays. Lux is the measurement of light intensity and a cloudy day is about 3,000 lux; a sunny day is 50,000 lux or more. Regular indoor light is less than 400 lux.
“Patients usually purchase a light box and use it in their homes, with a dose of 10,000 lux,” adds Iskandar. “As little as 30 minutes a day of sitting under the light box results in significant improvement in 60% to 70% of SAD patients.”
Iskandar recommends that people with certain medical conditions, such as retinal disease or diabetes, or people taking certain medications should have a special eye exam before considering light therapy.
Iskandar himself uses the light box from December to March. “I am originally from Egypt – a very sunny country,” says Iskandar, who has now lived through over thirty long Canadian winters. “Montreal winters are hard, and even more so because of the lack of light,” he adds.
With snow still on the ground and cold temperatures prevailing, effects of SAD could extend well past March. But some respite might not be that far off. “The effect of light therapy is through the eyes, not through skin exposure,” explains Iskandar. “Improvement is usually noticed by the third day.”