What is depression?

Depressionis colloquially defined as an affective disorder, i.e., a mood disorder that manifests itself primarily in a long-term depression of mood, which manifests itself as an overwhelming feeling of sadness and depression, loss of the ability to feel pleasure from activities that have brought it so far, and often a reduction in energy, which is reflected in increased fatigue and experiencing difficulties in taking up even the simplest activities. Longevity means that the condition must last a minimum of 2 weeks and that the person has symptoms most of the time. Additionally, in the course of depression, sleep disorders can be observed, mainly in the form of insomnia, appetite disorders (most often characterized by weakness), impaired concentration, and persistent guilt. In addition, the person affected by this disease often has a significantly lowered self-esteem, looks pessimistic about the future, and in the most severe episodes, they are accompanied by thoughts and suicidal tendencies. Depression tends to be recurrent, meaning that after one episode, which usually lasts for several months, there is a long period of so-called remission, i.e., lack of symptoms and good functioning, followed by another depressive episode.

What is seasonal depression?

Seasonal affective disorder (SAD) is a subtype of depressive disorder, a type of depression. What distinguishes this type of depression is its cyclical, seasonal-recurrent course, which means that depressive episodes most often appear in the patient in late fall or early winter and last until spring, when the mood improves. It happens, albeit much less frequently, that the symptoms of the disease are observed in spring and summer, and in the fall and winter it goes into remission.

How common is it?

SAD is believed to be a relatively common disease. The incidence varies in different populations, depending primarily on latitude. A greater prevalence of SAD is observed at higher latitudes. It is estimated that in the temperate zone about 4% of the population is affected by seasonal depression, while in areas where there is a shortage of sunlight, this percentage can be as high as 10%. It has also been noticed that the risk of the disease increases in people who migrate from lower to higher altitudes. SAD is 4 times more common in women than in men, and its incidence seems to decrease with age.

What causes seasonal depression?

Seasonal changes in the length of the day and night as well as the intensity of sunlight are considered a key factor in the development of SAD, which is why relapses are observed cyclically at specific seasons of the year. Genetic issues may also play a role, but so far, no specific gene has been shown to be mutated in disease progression. As in the case of a typical course of depression, SAD shows a decrease in the level of serotonin in the brain and disorders of other neurotransmitters, includingnoradrenaline,dopamine and melatonin. Both serotonin and melatonin help maintain the body’s daily rhythm associated with the seasonal night-day cycle. In people with seasonal depression, changes in serotonin and melatonin levels disrupt the normal sleep-wake rhythm. As a result, people with SAD have difficulty adjusting to seasonal changes in day length, resulting in disturbed sleep, mood, and behavior. It is also worth emphasizing the role of vitamin D, the deficiency of which, although not a key factor in the development of seasonal depression, may worsen its course and the response to the implemented treatment. Vitamin D is believed to promote the activity of serotonin. In addition to dietary vitamin D, the body produces vitamin D when exposed to sunlight on the skin. With less daylight in winter, people with SAD may have lower levels of vitamin D,

What symptoms might indicate seasonal depression?

The symptoms of seasonal depression are, in fact, not different from those of the typical course of depression mentioned above. However, it has been noticed that in the case of SAD with episodes in the fall-winter period, social withdrawal, a kind of “social hibernation” and atypical symptoms in the form of increased sleepiness and increased appetite, especially for sweet and high-carbohydrate foods, which lead to weight gain, are more common. . On the other hand, in less frequent episodes occurring in the spring and summer period, more characteristic are insomnia, decreased appetite resulting in weight loss, anxiety, restlessness and agitation, and a tendency to aggressive behavior.

How is seasonal depression diagnosed?

There is no specific test for seasonal depression. In order to make such a diagnosis, it is necessary that a given person meets the criteria for recurrent depressive disorders and, at the same time, that depressive episodes occur periodically, either in the fall / winter or spring / summer season. Importantly, the deterioration of the mood does not have to happen every year, although this is most often the case.

A doctor, not necessarily a psychiatrist, wanting to answer the question whether his patient suffers from depression may ask the following 2 questions, serving as the so-called screening test:

1. In the last month, have you felt / have any decreased interest or decreased pleasure?
2. In the last month, have you felt sad / sad, depressed / depressed, did you feel hopeless?

An affirmative answer to one of them means that the diagnosis should be deepened in this direction and the patient should be referred to a psychiatrist. Psychiatrists, on the other hand, have at their disposal various scales and tests that they can use to make an appropriate diagnosis or exclude depressive disorders. The Beck Depression Rating Scale is the most commonly used. However, no test can replace an in-depth psychiatric examination, which largely consists in talking to the patient and observing their behavior during the visit. Ultimately, the diagnosis can be made if at least 2 of the following 3 symptoms are present for at least 2 weeks: depressed mood, anhedonia, i.e. the previously mentioned inability to enjoy what has been the source of joy, and decreased energy. In addition, at least 2 of the symptoms should be found, such as difficulty concentrating and paying attention, decreased self-esteem, guilt, seeing the future in black colors, suicidal thoughts and behavior, various sleep disorders and appetite disorders, also of a different nature. It is important for the diagnosis of recurrent depression that between consecutive depressive episodes there should be at least 2 months free from mood disorders, which in the case of seasonal depression is automatically fulfilled, taking into account the fact that symptoms appear at a specific time of the year.

What is the treatment like?

Due to the fact that the most likely cause of the occurrence of seasonal depressive disorders is the reduction in the amount of sunlight in the autumn and winter months, phototherapy is the recognized and recommended method of treating seasonal depression. It has been used since the 1980s in the diagnosis of SAD. It consists in performing daily or every other day light irradiation treatments with an intensity of 2,500 to 10,000 lux in the morning. Their duration for the lowest intensity values ​​is approx. 2 hours, while for the highest values ​​it is approx. Half an hour. The phototherapy lamp should be positioned at the patient’s eye level. The entire course of therapy usually lasts from 2 to 3 weeks. As a result, the concentration of melatonin in the body, which is considered a depressant substance, is reduced. Phototherapy is considered a safe method, but it is important that people with diagnosed eye diseases should undergo an ophthalmological consultation to determine whether there are contraindications for using such strong light directly on the eyes. Additionally, people taking medications that make you more sensitive to sunlight may only need alternative treatments or light therapy under medical supervision. It is possible to purchase a phototherapy lamp individually to perform treatments at home. that make you more sensitive to sunlight may need alternative treatments or light therapy only under medical supervision. It is possible to purchase a phototherapy lamp individually to perform treatments at home. that make you more sensitive to sunlight may need alternative treatments or light therapy only under medical supervision. It is possible to purchase a phototherapy lamp individually to perform treatments at home.

Another method that can be used to treat seasonal depression is psychotherapy. Psychotherapy is considered to be the most effective in thecognitive behavioral therapy– CBT). Its aim is to help patients learn to cope with difficult situations. There is a form of CBT that is tailored specifically to people diagnosed with seasonal depression (CBT-SAD). Usually sessions are held twice a week for 6 weeks in the form of group meetings. In working with patients, the therapist focuses on replacing negative thoughts related to the winter season with more positive ones. CBT-SAD also uses a process called behavioral activation, which helps patients schedule enjoyable, engaging activities throughout the day to avoid the diminished activity they usually experience in winter. Research shows that both phototherapy and CBT-SAD are equally effective in relieving the symptoms of seasonal depression, while a faster effect is observed with phototherapy, and more long-term benefits come from psychotherapy. Both forms of treatment can be combined.

Since SAD, like other types of depression, is associated with impaired serotonin activity, antidepressants called selective serotonin reuptake inhibitors (selective serotonin reuptake inhibitors ) are– SSRIs) can also be used to treat SAD. Commonly used SSRIs include fluoxetine, citalopram, sertraline, paroxetine, and escitalopram. However, among the drugs classified as antidepressants, bupropion is considered the most effective and recommended in the treatment of SAD, which, in addition to treatment, can be used to prevent recurrence of seasonal depressive episodes. Bupropion is an inhibitor of norepinephrine and dopamine reuptake in the central nervous system, so thanks to its intake, the level of these neurotransmitters in the brain increases. It is considered a safe substance, but as with any drug, side effects should be taken into account. The most common are insomnia (therefore it is best to use the drug in the morning), headaches, a feeling of dry mouth, nausea and vomiting.

Considering the aforementioned role of vitamin D, it is recommended to supplement it in the dose of 800–2000 IU / day from October to April, depending on body weight and vitamin D supply in the diet. Its sources in the diet include yeast and fungi as well as animal products – mainly fatty sea fish (e.g. salmon, sardine, mackerel), fish oils (fish oil), eggs and liver.

Is it possible to cure seasonal depression completely?

Given that seasonal depression is a subtype of recurrent depressive disorder that has a chronic, relapsing course, complete recovery is rare. On the other hand, well-chosen therapy, compliance with medical recommendations, and care for a hygienic lifestyle can contribute to achieving a fairly good level of functioning in all areas of life. It should be emphasized that by taking advantage of the specific, seasonal course of SAD, thanks to which it is possible to predict when the disease will recur, preventive measures can be taken in the form of radiation or the use of antidepressants before symptoms appear. These steps are not always effective, but may result in a reduction in the severity of the episode and its shortening.