At some point, everyone will go through a period of sadness, grief, or loneliness. Unhappiness in a normal reaction to loss, namely life events like the death of a loved one, the breakup of a relationship, or other stressors such as poor health or financial difficulties.
Normal grief isn't pleasant, but people continue to function and know they'll get through it. Generally, the most intense feelings of grief fade within 6 to 8 weeks, although the entire process can take up to 4 years.
Normal grief can involve many of the same symptoms seen in depression. There may be difficulty concentrating, trouble sleeping, changes in appetite, loss of interest in pleasurable activities, a sense of fatigue, and feelings of guilt, anger, or loneliness.
However, normal grief improves over time, with an increasing number of "good days" versus "bad days." Depression stagnates and soaks into the psyche, becoming a fixed state of mood. In some cases, normal grief can tip over into depression.
Depression isn't just a passing mood. It involves changes in the brain that can be seen on functional magnetic imaging (fMRI) and positron emission tomography (PET) scans. The amygdala, the thalamus, and the hippocampus are regions of the brain thought to play a role in depression. In one study, the hippocampus was 9% to 13% smaller in depressed women. Likewise, activity in the amygdala is higher in clinically depressed people than in normal control groups. Other studies have linked depression to low levels of neurotransmitters. Antidepressants trigger the growth and branching of nerve cells in the hippocampus over a period of weeks, which is why patients often do not feel better until they have taken an antidepressant for several weeks or longer. Many different kinds of neurotransmitters play a role in depression, including serotonin, norepinephrine, dopamine, acetylcholine, glutamate, and gamma-aminobutyric acid (GABA).
There is no blood test for depression. Diagnosis relies on reported symptoms. A person with major depression (clinical depression) has at least 5 of the 9 signs of depression for 2 weeks or longer:
If you or someone you know has signs of clinical depression, you should immediately seek medical help at a behavioral health crisis unit or with a psychiatrist.
A 2000 study of 100 suicides by the Mayo Clinic found that the risk of suicide in people diagnosed with depression is nearly one in ten. The risk is highest in people who have thoughts of death or suicide. Many people do not verbalize these thoughts, so it is imperative to obtain psychiatric help for a loved one who seems withdrawn, blue, and shows changes in eating or sleep patterns.
The risk of depression is higher for some people than others. Depression has a genetic component, so it runs in families. People with low self-esteem, who have a pessimistic outlook, or who are overwhelmed easily by stress tend to be more at risk for depression. The incidence of depression is also higher in those who have endured ongoing childhood neglect and abuse, exposure to violence, or poverty.
There are many subtypes of depression, which are based on one's primary symptoms.
People with atypical depression react strongly to life circumstances. Their mood may lift briefly when something good happens, only to plummet when they experience rejection or other negative situations. They generally experience increased appetite, weight gain, excessive need for sleep, and pronounced fatigue. It is important to rule out hypothyroidism (low levels of thyroid hormone), because it can mimic atypical depression. Despite its name, atypical depression is extremely common.
People with melancholic depression display loss of appetite, problems with insomnia, and a diminished ability to enjoy once pleasurable hobbies and activities. Unlike atypical depression, melancholic depression is marked by a lack of mood reactiveness to outside circumstances. The individual's mood stays depressed, even when good things happen.
The most common form of depression is a single depressive episode that can start quickly over a few days or slowly over a period of weeks or months. While the individual experience the signs of clinical depression, the majority of these patients will have no further episodes of depression in their lifetimes.
Treatment of single episode depression reduces the risk that it will develop into recurrent depression. Recurrent depression is, as its name implies, is marked by episodes of depression with intervals of normal mood. These symptom-free intervals can last for weeks or for many years.
Dysthymia is diagnosed when an individual experiences depressed mood and related symptoms for at least 2 years. Although the symptoms are usually milder than in major depressive disorder, dysthymia robs life of enjoyment. It usually starts in adolescence and can last for decades. People with dysthymia can also experience episodes of major depression.
People with SAD usually experience atypical depression during certain seasons, notably fall and winter when sunshine is limited. When the seasons end, the person's mood returns to normal.
Bipolar I patients suffer from severe manic episodes that disrupt functioning alternating with depressive episodes. This change is mood can occur over a period of months or years of being in a healthy state, or it can occur very rapidly with fast cycles of mania and depression. Bipolar II patient exhibit less intense mania (hypomania) alternating with depression. In both instances, patients exhibit changes at both ends of the mood spectrum: the elevated mood of mania/hypomania and the down mood of depression. The treatment of depression in these individuals is an exacting science, because many antidepressants can trigger a manic episode.
Depression is one of the most common mental disorders and it is also one of the most treatable. Between 80% and 90% of depressed patients respond well to medication. These medications work by adjusting and "normalizing" brain chemistry. It can take several weeks for improvement to be seen, but if a patient feels little to no change, the dose may be altered or another medication may be used.
Cognitive behavioral therapy (CBT) is used with antidepressant medications to help patients recognize the distorted thinking that results from depression. CBT is generally not effective on its own, except for very mild cases of depression. However, it can help people with moderate to severe depression reframe their perspective and develop better coping strategies for dealing with stress and triggers.
If you have experienced any of the following symptoms for several or more days over the past 2 weeks, you should seek professional attention. If these issues have made it difficult for you to get along with other people or at work or home, you should seek help even if you do not experience them often. And, regardless of any other answers, if you have had thoughts of harming yourself or that you would be better off dead, you should seek immediate psychiatric help.