Seasonal affective disorder* is a form of depression also known as SAD, seasonal depression or winter depression. In the Diagnostic Manual of Mental Disorders (DSM-5), this disorder is identified as a type of depression – Major Depressive Disorder with Seasonal Pattern. Show People with SAD experience mood changes and symptoms similar to depression. The symptoms usually occur during the fall and winter months when there is less sunlight and usually improve with the arrival of spring. The most difficult months for people with SAD in the United States tend to be January and February. While it is much less common, some people experience SAD in the summer. SAD is more than just “winter blues.” The symptoms can be distressing and overwhelming and can interfere with daily functioning. However, it can be treated. About 5 percent of adults in the U.S. experience SAD and it typically lasts about 40 percent of the year. It is more common among women than men. SAD has been linked to a biochemical imbalance in the brain prompted by shorter daylight hours and less sunlight in winter. As seasons change, people experience a shift in their biological internal clock or circadian rhythm that can cause them to be out of step with their daily schedule. SAD is more common in people living far from the equator where there are fewer daylight hours in the winter. Symptoms and DiagnosisCommon symptoms of SAD include fatigue, even with too much sleep, and weight gain associated with overeating and carbohydrate cravings. SAD symptoms can vary from mild to severe and can include many symptoms similar to major depression, such as:
SAD may begin at any age, but it typically starts when a person is between ages 18 and 30. TreatmentSAD can be effectively treated in several ways, including light therapy, antidepressant medications, talk therapy or some combination of these. While symptoms will generally improve on their own with the change of season, symptoms can improve more quickly with treatment. Light therapy involves sitting in front of a light therapy box that emits a very bright light (and filters out harmful ultraviolet (UV) rays). It usually requires 20 minutes or more per day, typically first thing in the morning, during the winter months. Most people see some improvements from light therapy within one or two weeks of beginning treatment. To maintain the benefits and prevent relapse, treatment is usually continued through the winter. Because of the anticipated return of symptoms in late fall, some people may begin light therapy in early fall to prevent symptoms. Talk therapy, particularly cognitive behavior therapy (CBT), can effectively treat SAD. Selective serotonin reuptake inhibitors (SSRIs) are the type of antidepressant most commonly used to treat SAD. For some people, increased exposure to sunlight can help improve symptoms of SAD. For example, spending time outside or arranging your home or office so that you are exposed to a window during the day. (However, exposure to UV light from the sun can increase your risk of skin cancer.and you should talk with your doctor about risks and benefits.) Taking care of your general health and wellness can also help—regular exercise, healthy eating, getting enough sleep, and staying active and connected (such as volunteering, participating in group activities and getting together with friends and family) can help. If you feel you have symptoms of SAD, seek the help of a trained medical professional. Just as with other forms of depression, it is important to make sure there is no other medical condition causing symptoms. SAD can be misdiagnosed in the presence of hypothyroidism, hypoglycemia, infectious mononucleosis, and other viral infections, so proper evaluation is key. A mental health professional can diagnose the condition and discuss therapy options. With the right treatment, SAD can be a manageable condition. If you feel your depression is severe or if you are experiencing suicidal thoughts, consult a doctor immediately or seek help at the closest emergency room. National Suicide Prevention Lifeline – 800-273-TALK (8255). Autumn brings about many things: leaves on the ground, cooler temperatures, and of course Halloween. But while many look forward to a reprieve from the summer months, the start of the season can introduce new challenges. Seasonal depression—commonly known as seasonal affective disorder (SAD)—is a temporary condition estimated to affect 10 million Americans each year. Mariana Figueiro, PhD, Professor of Population Health Science and Policy at the Icahn School of Medicine at Mount Sinai, and Director of the Light and Health Research Center at Mount Sinai, explains the effects of SAD and how those who experience it can manage the disorder. What are the symptoms of seasonal affective disorder, and what causes it?Symptoms of seasonal affective disorder vary, but in general it includes feeling down or depressed as well as a lack of interest and energy. People tend to be sleepier and tend to overeat, especially carbohydrates. And, as with any depressive episode, there could be suicidal thoughts. These depressive symptoms occur at specific times of the year, typically the fall and winter, and there is a full remission at other times of the year, such as the spring and summer. Unfortunately, the cause of the disorder is still unclear, but there are some competing theories. One is that the start of autumn causes circadian rhythm disruption. Another is that the photoreceptors in the eye are not as sensitive to bright and dim light, and yet another is serotonin reuptake dysfunction, which is an imbalance in serotonin levels. But the most prominent theory is that the biological clock in the brain is out of phase with your natural light-dark patterns, affecting the timing of the sleep cycle. So, your biological clock is telling you that it is 6:30 in the morning, but your watch is telling you differently. That mismatch can be the cause of seasonal depression. Does the disorder only affect people who live in cities with long winters or are people in warmer climates affected as well?It tends to mostly affect people who live at higher latitudes, as these areas have less daylight availability in the winter months. In the United States, higher latitude areas will be the northernmost states such as Alaska, Washington, Michigan, New York, and Maine. In the New York metropolitan area, we have about 15 hours of daylight at the height of summer but only about nine hours in the dead of winter. This contrast is starker in areas that are farther north. Barrow, Alaska—the northernmost city in our northernmost state—has 67 straight days of darkness in the winter. Within high latitude populations, the prevalence of SAD varies between one and 10 percent. But it can happen at lower latitudes, it’s just less prevalent. How can I recognize and manage SAD?If you go to a physician, there are standardized questionnaires—such as the seasonal pattern assessment questionnaire—that you can take. But, in general, if year after year you begin to crave carbohydrates, lose energy, lose interest in things, overeat, and over sleep around October; that’s a good sign that you should seek a formal SAD diagnosis. Once you consult a physician, they will discuss how you can manage the disorder. There are two common ways to treat SAD. One would be medication—typically an antidepressant or a selective serotonin reuptake inhibitor—that would be prescribed by a physician. The other is non-pharmacological: light therapy. Exposing yourself to light—be it natural, morning light, or electric indoor light—will help resynchronize your biological clock so that it matches your local time. You can do this by adding more lights in the home, opening up your windows, and trying to be outside during daybreak. And if you work from home, try to sit facing a window. Making your environment brighter during the day will help get more light to the back of the eye, which is what you want in order to be an effective treatment for seasonal depression. Has light therapy been used to treat other illnesses?Yes it has. The Light and Health Research Center at Mount Sinai has done a number of studies showing that—outside of treating seasonal depression—there is a definite benefit to exposing people to bright days and dim nights. For instance, in a study with Alzheimer’s disease patients, the lighting was changed in their nursing homes and assisted living facilities to simulate bright days and dim nights. The results were a very robust, positive impact on their sleep, mood, and behavior. In other applications, we worked with persons with mild cognitive impairment and sleep disturbance from mild traumatic brain injury to see how light therapy can help. And we have been working with breast cancer and myeloma transplant patients to see if delivering light therapy during a transplant or during chemotherapy will help to minimize fatigue and improve their sleep. There are various applications. You can even use it to try to get your teenager to go to bed and wake up earlier. The addition of light can have many positive effects on life. Why does morning light help with seasonal affective disorder?It's thought that this type of light may cause a chemical change in the brain that lifts your mood and eases other symptoms of SAD , such as being tired most of the time and sleeping too much. Generally, the light box should: Provide an exposure to 10,000 lux of light.
How does light treat seasonal affective disorder?The light produced by the light box simulates the sunlight that's missing during the darker winter months. It's thought the light may improve SAD by encouraging your brain to reduce the production of melatonin (a hormone that makes you sleepy) and increase the production of serotonin (a hormone that affects your mood).
How effective is light therapy for SAD?By helping your circadian rhythm and balancing serotonin levels, research shows that light therapy may improve depression. A study shows that whether light therapy was used alone or with fluoxetine, an antidepressant medication, it was effective in improving symptoms of depression.
Does sunlight through window help with seasonal affective disorder?While exposure to sunlight doesn't completely eliminate the risk of developing seasonal depression, it can go a long way in preventing and minimizing the impact it has. In fact, besides exposure to sunlight, one of the most commonly recommended treatments for seasonal depression is the use of a light therapy box.
|
