What is depression?

Depression (major depressive disorder) is a common and serious medical illness that negatively affects how you feel, think, and behave.

Fortunately, it can also be treated. Depression causes feelings of sadness and/or a loss of interest in activities you once enjoyed. This can lead to various emotional and physical problems and can decrease your ability to function at work and at home.

Symptoms of depression can vary from mild to severe and may include the following conditions:

• Feeling sad or having a depressed mood
• Loss of interest or pleasure in activities once enjoyed
• Changes in appetite – weight loss or gain unrelated to dieting
• Trouble sleeping or sleeping too much
• Loss of energy or increased fatigue
• Increase in purposeless physical activity (e.g., inability to sit still, pacing, handwringing) or slowed movements or speech (these actions must be severe enough to be observable by others)
• Feeling worthless or guilty
• Difficulty thinking, concentrating, or making decisions
• Thoughts of death or suicide

Symptoms must last at least two weeks and must represent a change in your previous level of functioning to diagnose depression.

Additionally, medical conditions (e.g., thyroid problems, brain tumors, or vitamin deficiency) can mimic depression symptoms, so it’s important to rule out general medical causes.

Depression affects one out of 15 adults (6.7%) in any given year. And about one in six people (16.6%) will experience depression at some point in their lifetime. Depression can occur at any age, but on average, it first appears during the late teens to mid-20s.

Women are more likely than men to experience depression. Some studies suggest that one-third of women will experience a major depressive episode during their lifetime. There is a high degree of heritability (about 40%) when first-degree relatives (parents/children/siblings) have depression.

Depression differs from sadness or grief

The death of a loved one, job loss, or the end of a relationship are difficult experiences that a person can endure. It’s normal for feelings of sadness to develop in response to such situations. Those who are experiencing loss often describe themselves as “depressed.”

However, being sad is not the same as having depression. The grieving process is natural and unique to each individual and shares some of the same features of depression. Both grief and depression may involve intense sadness and withdrawal from usual activities. They also differ in important ways:

• In grief, painful feelings come in waves, often mixed with positive memories of the deceased.

In major depression, mood and/or interest (pleasure) are decreased for most of two weeks.

• In grief, self-esteem is usually maintained. In major depression, feelings of worthlessness and self-loathing are common.
• In grief, thoughts of death may surface when you think or fantasize about “joining” the deceased loved one. In major depression, thoughts are focused on ending one’s life due to feelings of worthlessness or unworthiness of life or inability to cope with the pain of depression.

Sadness and depression can coexist. For some individuals, the death of a loved one, job loss, or being a victim of a physical attack or major disaster can lead to depression. When sadness and depression occur simultaneously, the sadness is more intense and lasts longer than sadness without depression.

Distinguishing between sadness and depression is important and can help people get the help, support, or treatment they need.

Risk factors for depression

Depression can affect anyone – even someone who appears to be living in relatively ideal circumstances.

Several factors may play a role in depression:

• Biochemistry: Differences in certain chemicals in the brain may contribute to depression symptoms.
• Genetics: Depression can run in families. For example, if one identical twin has depression, the other has a 70 percent chance of developing the illness sometime in life.
• Personality: People with low self-esteem, who are easily overwhelmed by stress, or who are generally pessimistic seem to be more likely to experience depression.
• Environmental factors: Continuous exposure to violence, neglect, abuse, or poverty may make some people more vulnerable to depression.

How is depression treated?

Depression is among the most treatable of mental disorders. Between 80% and 90% percent of people with depression eventually respond well to treatment. Almost all patients gain some relief from their symptoms.

Before a diagnosis or treatment, a health professional should conduct a thorough diagnostic evaluation, including an interview and a physical examination. In some cases, a blood test may be done to make sure depression is not due to a medical condition like a thyroid problem or vitamin deficiency (medical causes reverse the symptoms that mimic depression).

The evaluation will identify specific symptoms and explore medical and family history, as well as cultural and environmental factors, to arrive at a diagnosis and plan the course of action.

Medications

Brain chemistry may contribute to an individual’s depression and may impact their treatment. For this reason, antidepressant medications may be prescribed to help modify brain chemistry. These medications are not sedatives.

They do not create dependence. Generally, antidepressants do not have a stimulant effect on people who do not have depression.

Antidepressants may lead to some improvement within the first week or two of use, but the full benefit may not be seen for two to three months. If a patient feels little or no improvement after several weeks, their psychiatrist may change the dose of the medication or add or switch to another antidepressant. In some cases, other psychotropic medications can be helpful. It’s important to inform your doctor if a medication is not working or if you experience side effects.

Psychiatrists usually recommend patients continue taking medications for six or more months after symptoms improve. Long-term maintenance treatment may be suggested to decrease the risk of future episodes for certain people with high risk.