Depression
Depression is a prevalent and serious mood disorder that affects around 280 million people worldwide, making it the leading cause of illness and disability around the globe. Depression is characterized by feelings of sadness, but more than just a feeling of being down in the dumps. This disorder affects one’s thoughts, feelings and actions, impacting the ability to function in day to day life, from enjoying one’s passions to succeeding in the workplace. If you think you may suffer from depression, it’s best to get help from a health professional, as this disorder isn’t one that you can simply snap out of.
Who is Most Affected by Depression?
The term “depression” is typically used to describe major depressive disorder, which could be seen as its most basic form. Aproximently 5% of adults experience depression around the world. This mood disorder affects about 1 in 15 adults in any given year, and 1 in 6 adults will experience it at some point throughout their life. Although anyone can get major depressive disorder, certain risk factors make some members of the population more susceptible than others.
Women are diagnosed with depression more often than men. However, men are also less likely to share about their feelings and seek help for emotional issues, making it difficult to accurately compare rates of depression between women and men. People in the LGBTQIA+ community have also been shown to have higher rates of depression compared to some other populations. One of the biggest risk factors is hereditary, so having a first-degree relative like a parent or sibling with depression makes you much likelier to experience it yourself. Although one can suffer from depression at any age, those between 18 and 29 years old have the highest rates.
Symptoms of Depression
Although depression, or major depressive disorder, has made its way into our everyday vocabulary as a feeling of sadness and disinterest in activities, there are a range of symptoms that can be used to diagnose it. Symptoms of depression can include:
● Feelings of sadness, pessimism or hopelessness
● Feelings of irritability, anxiety or frustration
● A loss of interest or enjoyment in activities and hobbies
● Insomnia or oversleeping
● Lack of appetite or overeating
● Feelings of fatigue or low energy
● Feelings of worthlessness or guilt
● Becoming withdrawn or detached
● Slowed movements or speech
● Increase in aimless physical activity like pacing
● Difficulty concentrating, remembering or making decisions
● Physical pains or digestive problems that have no clear physical cause or treatment
● Thoughts of death or suicide
● Engaging in high-risk activities
● Inability to meet everyday life responsibilities
Most people who are depressed experience a number of symptoms, which can range from mild to severe. Not everyone who suffers from depression has every symptom, and some affected people may only have a few. Because of this, depression looks different depending on the person.
Causes of Major Depressive Disorder
The exact cause of depression is unclear, but researchers know that there are a number of factors. Some potential causes are:
● Brain chemistry- Changes or imbalances in brain chemicals like serotonin, norepinephrine and dopamine may cause depression.
● Genetics- Major depressive disorder is more common in people with a close relative who has also suffered from the disorder, which means that genetics play a role.
● Life events- Difficult life events may cause depression, for instance the loss of a loved one, a breakup, financial struggles, isolation or the loss of a job.
● Childhood development- those who experienced adverse childhood experiences (ACEs) like abuse, neglect and trauma are more likely to suffer from clinical depression as adults.
Seasonal Affective Disorder
Seasonal affective disorder (SAD), or seasonal depression, is a kind of depression caused by a change in the seasons. Most commonly, seasonal affective disorder is triggered by the start of fall or winter and is alleviated by the beginning of spring or summer. Although many people experience feeling a bit sad during the dark days of winter, true seasonal affective disorder is more than just feeling low. This weather-based form of depression impacts your everyday life, changing how you feel and think.
A small subset of the population gets seasonal affective disorder in the summer, called summer depression. This begins in the late spring or early summer and ends in the fall. However, the majority of those affected by seasonal depression experience it in the winter.
Who is Most Affected by Seasonal Affective Disorder?
About 5% of adults in the U.S. experience seasonal depression, and 10-20% of the population in the U.S. experience a more mild “winter blues”. This form of depression is also more common in women than men, but it’s unclear how much of this is due to the fact that women are more likely to seek help for mood disorders. Seasonal affective disorder typically develops between the ages of 18 and 30. Those who have another mood disorder, for example: bipolar disorder, are more likely to get seasonal affective disorder, along with those who live in places with especially low sunlight in the winter. People who live in cloudy places and areas far from the equator are more susceptible to seasonal affective disorder compared to those living close to the equator and with more daily sunlight.
Symptoms of Seasonal Affective Disorder
Seasonal affective disorder has the same symptoms as major depressive disorder, but this form of depression is connected to the seasons. Symptoms of seasonal affective disorder can include:
● Feelings of sadness, pessimism or hopelessness
● Feelings of irritability, anxiety or frustration
● A loss of interest or enjoyment in activities and hobbies
● Insomnia or oversleeping
● Lack of appetite or overeating
● Feelings of fatigue or low energy
● Feelings of worthlessness or guilt
● Becoming withdrawn or detached
● Slowed movements or speech
● Increase in aimless physical activity like pacing
● Difficulty concentrating, remembering or making decisions
● Physical pains or digestive problems that have no clear physical cause or treatment
● Thoughts of death or suicide
● Engaging in high-risk activities
● Inability to meet everyday life responsibilities
If these symptoms happen throughout the year and seem unconnected to the seasons or weather, you may have major depressive disorder rather than seasonal affective disorder. However, if these symptoms arise in the late fall or early winter and go away by the late spring or early summer, they may point to seasonal affective disorder.
Causes of Seasonal Affective Disorder
The specific causes of seasonal depression are unknown, but researchers have a number of theories. While a lack of sunlight is the obvious cause, there are theories about why this leads to depression. Some potential causes of seasonal affective disorder are:
● Biological Clock- one potential source is the biological clock, which regulates your mood, sleep and hormones. When the sunlight decreases, your biological clock reacts, which can make it difficult to readjust to the shorter, darker days.
● Chemical imbalance in the brain- Serotonin is a brain chemical that causes feelings of happiness. Sunlight regulates serotonin, so a lack of sunlight can lead to lower serotonin activity. These lower serotonin levels can cause depression.
● Vitamin D deficiency- Serotonin is also affected by vitamin D, which is produced by sunshine. A lack of sun in the winter can cause vitamin D deficiency, which impacts serotonin levels and can cause changes in your mood.
● Melatonin Increase- Melatonin is a hormone that your brain produces as a response to darkness. This hormone causes drowsiness and helps you to sleep at night. The lack of sunlight may cause your brain to overproduce melatonin, causing sluggishness and low energy throughout the winter.
● Negative thoughts about winter- Those who suffer from seasonal affective disorder often feel anxiety, dread and negative thoughts about the winter. This can function as a self-fulfilling prophecy, and these negative thoughts can compound the symptoms that are already happening.
Persistent Depressive Disorder
Persistent depressive disorder is mild to moderate depression that persists, lasting for two years or more. Those with persisitant depressive disorder have a sad, dark mood that continues for the majority of the day on most days. Previously called dysthymia or dysthymic disorder, this mood disorder is common and can happen to anyone.
Persisitant depressive disorder, or chronic depression, is different from major depressive disorder because it involves less severe symptoms that last for a longer period of time. Those who suffer from chronic depression experience mild to moderate symptoms, but they’ll deal with these for a while; at least two years in adults and at least one year in children and teenagers.
Who Is Most Affected by Persistent Depressive Disorder?
Chronic depression is diagnosed more often in women. Like other forms of depression, those who have relatives with the disorder are more likely to experience it. Less common than the other forms of depression, 3% of the population in the United States suffers from persisitant depressive disorder at some point in their lives.
Symptoms of Persistent Depressive Disorder
The symptoms of persisitant depressive disorder are similar to those of major depressive disorder, but they happen with less intensity and for a longer period of time. Symptoms of persisitant depressive disorder can include:
● Low, dark mood
● Fatigue or low energy
● Loss of interest in activities or hobbies
● Feelings of hopelessness or worthlessness
● Lack of appetite or overeating
● Insomnia or oversleeping
● Difficulty concentrating
● Low self-esteem
● Difficulty meeting everyday responsibilities
● Feelings of irritability, anxiety or frustration
● A loss of interest or enjoyment in activities and hobbies
● Avoidance of social activities
People with persisitant depressive disorder can have any combination of these symptoms, and many will suffer from a bout of major depression at some point as well. When this occurs, it’s called “double depression.”
Causes of Persistent Depressive Disorder
The exact causes of persisitant depressive disorder are still unknown, but scientists can point to a number of possible roots. Some potential causes are:
● Brain chemistry- Changes or imbalances in brain chemicals like serotonin, norepinephrine and dopamine may cause chronic depression.
● Genetics- Persisitant depressive disorder is more common in people whose relatives have also suffered from the disorder. However, researchers haven’t yet found the genes linked to persistent depressive disorder.
● Life events- Difficult life events may cause persisitant depressive disorder, for instance a loss of a loved one, breakup, financial struggles or loss of a job. Those with chronic stress and trauma are also at higher risk of developing persisitant depressive disorder.