Clinical depression is more than just feeling down. It’s characterized by persistent feelings of sadness, hopelessness, and worthlessness that don't go away on their own. Feeling down on occasion is a normal and important part of life. Sad and distressful events occur in everyone's life, and responding to them emotionally is healthy. However, feeling miserable consistently and without any sense of hope isn’t normal. This symptom can indicate depression, which is a serious medical condition.
People experience this mood disorder in different ways. There are also different types of depression. The type of depression you have helps determine the kind of medical treatment you should receive. According to the Diagnostic and Statistical Manual of Mental Disorders, the two most common types of depression are major depressive disorder (MDD) and persistent depressive disorder (PDD).
Major depressive disorder
People with major depression experience an almost constant state of sadness, emptiness, and despair for at least two weeks. MDD is a debilitating disease that can seriously affect your health and well-being. If you have MDD, you may be unable to enjoy activities that you once found pleasurable, and you may have a hard time:
Many people use the word "depression" to describe this mood disorder. However, medical professionals prefer to use the term "major depressive disorder" or "major depression." Both of these terms describe a specific medical condition rather than a general group of behaviors that don’t meet the criteria for an MDD diagnosis. When people refer to "clinical depression," they’re typically referring to MDD.
In some cases, the symptoms and the course of this disorder are significantly different than usual. This can be due to certain behaviors or other factors. MDD can be a single episode, it can be ongoing, or it can recur.
There following are different subtypes of MDD:
Major depressive disorder with atypical features
People with MDD are uniformly depressed, but people who have MDD with atypical features have what's called mood reactivity. That is, you experience temporary emotional highs from good news and lows from bad news. Some mental health experts believe that this type of depression may be a milder form of bipolar disorder known as “cyclothymia.” Atypical depression often first appears in the teenage years, and it can continue into adult life.
People with atypical depression can also have:
- significant weight gain
- an increase in appetite
- excessive sleep
- leaden paralysis, or a sense of heaviness in the arms or legs
- sensitivities to rejection
Major depressive disorder with peripartum onset
This condition was once called postpartum depression. This form of MDD is diagnosed if MDD occurs during pregnancy or within four weeks after you’ve delivered your baby.
It’s estimated that 3 to 6 percent of women will experience this type of MDD during pregnancy or in the postpartum period. New research shows that about 50 percent of these episodes begin before delivery. The cause of this isn’t known, but medical experts changed the name from postpartum depression to peripartum depression because of this statistic. Women with this disorder often have:
- panic attacks
- a loss of appetite
- problems sleeping
- feelings of worthlessness
In rare cases, this type of depression can have psychotic features.
Major depressive disorder with seasonal patterns
MDD with seasonal patterns was formally called seasonal affective disorder. This diagnosis only applies to recurring episodes of MDD. If you have this condition, you experience depression symptoms during a certain time of the year.
Most commonly, people will experience depression symptoms in the fall or winter, and the symptoms will go away in the spring and summer. However, it’s possible to experience depression in the spring and summer. These depressive symptoms cannot be the cause of a seasonal stressor, such as the winter holiday season or completing seasonal work.
Major depressive disorder with melancholic features
Some common symptoms of this condition include:
- a loss of pleasure in all or most activities
- no reaction to something good happening
- psychomotor agitation, such as pacing or hand wringing
- increased depression in the morning
MDD has melancholic features if the symptoms mentioned above develop in the most severe stage of a depressive episode.
Major depressive disorder with psychotic features
MDD can occur with psychotic symptoms, such as delusions or hallucinations. The content of the psychotic delusions tends to be consistent with feelings of depression. For example, someone who has MDD with psychotic features may hear voices telling them that they’re worthless and don’t deserve to live.
Major depressive disorder with catatonia
Along with the symptoms of MDD, people with cationic depression experience severe psychomotor disturbances. The symptoms involve either the sudden inability to move or an excessive amount of movement that seems to have no purpose.
Persistent depressive disorder
Formerly called dysthymia, PDD often has fewer or milder symptoms than major depression. PDD differs from MDD in symptom severity, and it lasts longer than MDD. The condition is characterized by a depressed mood most of the time for at least two years, along with at least two of these symptoms:
- low self-esteem
- poor concentration
- a poor appetite
- excessive sleep
- a lack of energy
Other depressive disorders
You may have a depressive disorder that’s characterized by depressive symptoms but that doesn’t fit into the category of MDD, PDD, or another mood disorder. This is called “depressive disorder not otherwise specified.” Examples of this type of disorder include the following:
Unspecified depressive disorder
A person with this disorder may have multiple characteristics of other forms of depression.
Recurrent brief depression
This classification of depression indicates symptoms that last from two to 13 days. It occurs at least once per month for twelve months. It’s a milder form of depression that’s usually treated with therapy.
Adjustment disorder with depressive features
Occasionally, some single event or stressor can cause a psychological response so intense that it results in a mood low enough that it can be considered a type of depression. This condition is referred to as adjustment disorder with depressive features. Usually, this condition is temporary.
Other mood disorders that cause depression symptoms
Some mood disorders cause the symptoms of depression, but they aren’t depression. It’s essential to recognize that these disorders aren’t depression. Treatment for these other mood disorders may be very different than treatment for depression.
MDD is often considered the most serious form of depression in terms of symptom severity and how long it can last. Depression can also occur due to other conditions, such as:
- a disruptive mood dysregulation disorder, which is often diagnosed in children and is characterized by frequent and severe outbursts of anger
- premenstrual dysphoric disorder, which is a more severe type of premenstrual syndrome
- a substance or medication-induced depressive disorder, which is depression caused by the use of an illegal drug or the side effects of a prescribed drug
- certain chronic illnesses, such as Parkinson’s disease
Depression means more than just feeling down. It can often interfere with your daily responsibilities and relationships. It may last for months or years and often becomes worse without treatment. However, depression is a treatable medical condition. Those who seek treatment often see improvements in their symptoms.