What Is Major Depressive Disorder? 6 Types, Causes & Symptoms

What is depression?

Depression causes sadness and/or a loss of interest in activities once enjoyed. It can also decrease a person’s ability to function at work and home.

The American Psychiatric Association defines major depressive disorder (depression) as a common, but serious, medical illness that negatively affects how one feels, thinks and acts.

Depression causes sadness and/or a loss of interest in activities once enjoyed. It can lead to a variety of emotional and physical problems and decrease a person’s ability to function at work and home.

What is a nervous breakdown?

A nervous or mental breakdown is a common term used to describe a period of intense mental distress during which one is unable to function in everyday life. This term is used to refer to a wide variety of mental illnesses, including depression, anxiety and acute stress disorder.

What are the causes of depression?

Genetic causes of depression

First-degree relatives of depressed individuals are about three times as likely to develop depression

External stressors causing depression

Stressors can be personal, familial, social and environmental, such as:

Chronic pain
Medical illness
Psychosocial stress
Lack of sleep
Impaired social supports
Caregiver burden
Loneliness
Bereavement
Negative life events
Loss of a loved one
Harassment
Bullying
Alcohol and drug abuse
Certain medications
Domestic abuse
Poor parent-child relationship
Traumatic life events
Major life changes – divorce, loss of employment, etc.

Risk-factor interactions that cause depression

The relationship between genetic vulnerability, environmental stressors and brain structural abnormalities are risk factor interactions in the development of depression.

Neuroendocrine abnormalities and neurodegenerative diseases

Abnormalities of the neurotransmitter systems may cause depression.
Neurodegenerative diseases (especially Alzheimer and Parkinson), stroke, multiple sclerosis, seizure disorders, cancer and chronic pain have been associated with higher rates of depression

Vascular depression

Medical problems that affect blood flow to the brain may also trigger depression:

Patients experience a higher incidence of depression following a stroke
Higher prevalence of ischemic (loss of oxygenation) brain changes exist in older adults with depression
A strong association exists between depression and heart disease as well as depression and diabetes
Higher rates of depression exist among patients with vascular dementia

What are the signs and symptoms of major depressive disorder?

At least five of the following symptoms must have been present during the same two-week period (and at least one of the symptoms must be diminished interest/pleasure or depressed mood):

Depressed mood: For children and adolescents, this can also be irritability.
Diminished interest or loss of pleasure in almost all activities (anhedonia)
Significant weight change or appetite disturbance: In children, this can be a failure to gain weight and weight gain in adults
Sleep disturbance (insomnia or hypersomnia)
Fatigue
Feelings of worthlessness
Diminished ability to think or concentrate and indecisiveness
Recurrent thoughts of death, recurrent suicidal ideation or a suicide attempt

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What is depression with anxious distress?

Anxious distress may be added to a depression diagnosis if at least two of the following symptoms are present:

Feeling tense
Unusually restless
Difficulty concentrating
Fear that something awful may happen
Feeling of potential loss of control

Severity is further specified as:

Mild: two symptoms
Moderate: three symptoms
Moderate-severe: four or five symptoms
Severe: four or five symptoms with shaking or other movement symptoms (motor agitation)

What is depression with melancholic features?

At least three of the following are required for this specific diagnosis:

A depressed mood that is distinctly different from the kind that is felt when a loved one is lost
Depression that is worse in the morning
Waking up 2 hours earlier than usual
Observable psychomotor retardation or agitation
Significant weight loss or anorexia
Excessive or inappropriate guilt

QUESTION

Depression is a(n) __________ .
See Answer

What is depression with catatonia (abnormal movement and behavior)?

Stupor (near state of unconsciousness)
Catalepsy (trance/seizure with unconsciousness, rigidity, loss of sensation)
“Waxy flexibility” of skeletal muscles, meaning limbs stay in a position the doctor puts them in with only mild initial resistance, like bending soft wax
Mutism
Negativism
Stereotypy (purposeless persistent repetition of an act)
Agitation without provocation
Grimacing
Echolalia (meaningless repetition of another person’s words)
Echopraxia (meaningless repetition of movements of others)

What is postpartum depression (postpartum blues)?

Depression in the postpartum period is common and potentially serious. Up to 85% of women can develop mood disturbances during the period after childbirth. Postpartum depression is characterized by fluctuating mood, tearfulness, irritability and anxiety.

What is seasonal affective disorder (SAD)?

Depression symptoms worsen during the winter and improve during the summer.

Major Depressive Disorder with Psychotic Features

This type of depression with psychotic features like:

Delusions
Hallucination
Mood instability

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What is metabolic depression?

Individuals with depression who have metabolic syndrome may be more likely to have persistent or recurrent depression.

What are the risks and complications of depression?

Depression may cause one to act on suicidal thoughts or promote substance abuse, disrupt interpersonal relationships and make it difficult to work.

What are the risk factors for suicide?

Major depression
Older age
Male sex
Previous history of suicide attempts
Burden of medical disease and presence of a current serious medical condition
Recent stressful life events
Lack of social support
Family discord, being widowed or divorced
Presence of a gun in the home
Unexplained weight loss
Severe anxiety
Real or perceived lack of meaningful life pursuits
Presence of a specific suicide plan and its rehearsal

What is the prognosis for major depressive disorder?

Major depressive disorder causes significant distress and makes it difficult for people to form relationships, enjoy leisure or be functional at work. With appropriate medical treatment, therapy and emotional support, 70-80% of patients may be cured or at least drastically reduce their symptoms.