Seasonal affective disorder (SAD), also known as seasonal depression, is a condition triggered by the changing seasons. It is more commonly experienced during fall and winter but can also occur in the summer. Many people go through periods of mood changes, feeling sad and not quite like themselves. Sometimes, these mood shifts align with the changing seasons and may be a sign of major depressive disorder (MDD) with a seasonal pattern, commonly referred to as seasonal affective disorder or seasonal depression.
Prevalence and Factors
Seasonal affective disorder is particularly prevalent in more northern regions where days are shorter and nights are longer. The condition affects between 1% and 10% of individuals, varying by country. Women are four times more likely to experience seasonal affective disorder than men, and it usually starts between ages 18 and 30. While winter depression is more common, some people experience mood changes during the onset of summer, known as summer-pattern or summer-type seasonal affective disorder.
Symptoms of Seasonal Depression
The symptoms of seasonal depression include feelings of sadness and depression that coincide with changing seasons, most commonly in fall or winter when temperatures drop and days shorten. These symptoms naturally subside as the affected season transitions. Winter depression is often referred to as “winter blues” when symptoms are milder. Symptoms may include oversleeping, overeating, carb cravings, weight gain, social withdrawal, and a desire to “hibernate.” Summer depression, on the other hand, may cause trouble sleeping and lack of appetite, leading to weight loss, restlessness, and anxiety.
Causes and Treatment Options
The exact cause of seasonal affective disorder is not fully understood, but several factors may contribute to its development. One theory suggests that individuals with seasonal affective disorder have lower levels of serotonin, the hormone responsible for regulating mood. Lack of sunlight exposure during winter months can impact serotonin levels. On the contrary, summer depression may be triggered by heat, humidity, and excessive light exposure, leading to an overproduction of melatonin, which promotes sleepiness.
Treatment options for seasonal depression include various strategies that individuals can try on their own. For winter depression, increasing exposure to natural light, utilizing light therapy with specialized lamps or full spectrum light bulbs, maintaining a regular sleep schedule, exercising regularly, and eating a balanced diet may be helpful. For summer depression, spending time in darkened rooms and staying cool are recommended. Regular exercise indoors can also be beneficial.
Cognitive Behavioral Therapy for Insomnia (CBT-i)
In addition to the aforementioned strategies, Cognitive Behavioral Therapy for Insomnia (CBT-i) can be an effective treatment option for individuals with seasonal affective disorder. CBT-i focuses on addressing sleep problems that may contribute to depressive symptoms. It involves identifying and challenging negative thought patterns and behaviours related to sleep. Techniques such as sleep restriction therapy and stimulus control therapy are commonly used in CBT-i to improve sleep quality and establish a healthier sleep routine.
When coping strategies alone are not sufficient, it is essential to seek professional help. Healthcare professionals may recommend psychotherapy and medications for more severe cases. Ultimately, a combination of therapy, medication, self-care strategies, and CBT-i provides the most effective treatment approach for seasonal affective disorder.