Major depressive disorder, also known as clinical depression, is a common mental health disorder that impacts a person’s mood, cognition and behavior. Major depressive disorder impacts normal, daily functioning in academic, occupational and social realms.

Sadness is a normal human emotion, especially when it pertains to challenging life events. Occurrences like the death of a loved one, the end of a relationship or the loss of a job can cause considerable distress and unhappiness. Normal bouts of sadness are fleeting and do not persist for long periods of time. However, when feelings of sadness become pervasive and unrelenting, it may be indicative of a more significant problem. Major depressive disorder, also known as clinical depression, is a common mental health disorder that impacts a person’s mood, cognition and behavior. Major depressive disorder impacts normal, daily functioning in academic, occupational and social realms.

What is Major Depressive Disorder?

Major depressive disorder is a serious mental health disorder categorized by sad feelings and depressed mood, lack of motivation and decreased interest in once enjoyable activities. Some individuals experience clinical depression at one point in their life, while other people have multiple experiences. Furthermore, some people have short bouts of depression, while others have symptoms that are always present. Major depressive disorder can greatly impact familial, social and personal relationships. Individuals tend to continually grapple with feelings of hopelessness, guilt and low self-esteem, which ultimately can lead to thoughts of self-harm or suicide. Individuals with major depressive disorder may feel like they are in a bottomless pit with no escape and have no hope or optimism that they will ever get out.

Types of Major Depressive Disorder

There are several different types of major depressive disorder, also termed as specifiers, which clarify the length and essential characteristics of depression:

  • Seasonal affective disorder (SAD) occurs mostly in the winter months when there is decreased sunlight.
  • Psychotic depression arises if an individual is experiencing hallucinations or delusions, which may emerge from past trauma.
  • Postpartum depression is present in new mothers experiencing hormonal fluctuations after childbirth that can be exacerbated by stressors relating to raising a child.
  • Melancholic depression encompasses the most common signs of depression, including weight fluctuation, diminished interest in activities and lack of motivation.
  • Catatonic depression occurs in individuals experiencing motor difficulties, such as immobilization or involuntary movements and behavioral problems

Symptoms of Major Depressive Disorder 

Symptoms of major depressive disorder include:

  • Low mood and anhedonia, or loss of interest in activities and things that were once enjoyable
  • Preoccupation with feelings of worthlessness and hopelessness
  • Impaired concentration and memory
  • Isolation from socialization
  • Diminished sexual libido
  • Irritability and agitation
  • Suicidal or self-harming thoughts
  • Disrupted sleeping patterns, such as trouble falling or staying asleep.
  • Fatigue or loss of energy
  • Headaches
  • Changes in eating habits and weight fluctuations
  • Lethargy and fatigue

Depression manifests differently in children, as they may appear more irritable and agitated than sad. Children tend to lose interest in academics and illustrate a decline in their academics.  Children can be needy, reliant, timid and apprehensive.

Causes of Major Depressive Disorder 

The precise cause of depression is unknown; however, depression is believed to be caused by an amalgam of genetic, environmental and psychological factors. Genetic factors include biology, a family history of mood disorders and hormones. Environmental factors relate to childhood events, abuse, socioeconomic conditions or exposure to stress. Psychological and emotional factors are related to self-esteem, personality and coping mechanisms. These factors cause alteration to brain functioning and neural pathways.

Major depressive disorder may also develop from alcohol or drug abuse, various medical conditions or certain medications.

How is Major Depressive Disorder Diagnosed?

A licensed mental health practitioner or psychiatrist needs to conduct a clinical assessment to diagnose an individual with major depressive disorder. The licensed mental health practitioner or psychiatrist will collect information regarding developmental and family history, psychiatric history, past symptoms and presenting problems. The assessment will also include a mental status examination, which evaluates mood and thought content.

An individual must meet diagnostic criteria outlined in the Diagnostic and Statistical Manual of Mental Disorders (DSM 5) and portray at least five or more symptoms daily for at least a two-week period to obtain a major depressive disorder diagnosis. Some of these symptoms may include:

  • Feelings of sadness or petulance for most of the day, almost every day
  • Loss of interest in activities that were previously pleasurable
  • Disrupted eating habits, such as alterations in appetite and fluctuations in weight
  • Disturbed sleeping habits, such as sleeping excessively or difficulty falling asleep
  • Feelings of agitation and impatience
  • Loss of energy and increase in fatigue
  • Low self-worth or feelings of guilt
  • Trouble concentrating, contemplating or rendering decisions
  • Thoughts of self-harm or suicide

Before going to a mental health practitioner, a general physician may perform major depressive disorder test. Additionally, a physician may run a battery of blood tests to eliminate medical causes that could potentially account for depressive symptoms.

Who is at Risk for Major Depressive Disorder?

Individuals with a childhood history of abuse, neglect or trauma are at increased risk for developing major depressive disorder. Physical, sexual and emotional abuse are all correlated with the severity, span and response to treatment. A serotonin transporter gene links to an elevated risk of depression. An individual is at increased risk of having another major depressive episode if they have already had at least one incident. Co-occurring sickness and medical circumstances also dictate risk in having a major depressive episode.

Major Depressive Disorder Statistics 

Researchers have conducted several studies to better understand major depressive disorder, some statistics that have been revealed in research include:

  • Depression impacts 16 million people in the United States per year
  • Lifetime frequency of depression in the United States is more than 20-26 percent for women and 8-12 percent for men
  • The mean age of onset of major depression is 32 years old
  • Major depression impacts about 6.7 percent of the United States population over 18 years of age
  • Between 20 and 25 percent of adults suffer an episode of major depression at some point in their lifetime
  • Roughly twice as many women have major depression compared to men
  • Between 2-8 percent of adults with major depression die by suicide and about 50 percent who die by suicide had depression or another mood disorder
  • Approximately 40 percent of the risk for depression links to genetics

Spells of sadness are normal and an integral part of the human condition. Feelings of sadness can be in response to negative life events, specific challenges or certain losses and often dissipate over time. Additionally, these feelings of sadness do not profoundly impact overall functioning in several life domains. When an individual cannot ease depression, when sadness interferes with daily performance and when grief mixes with feelings of hopelessness, it can be indicative of a more serious disorder. Major depressive disorder is common but can be dangerous, especially when an individual experiences self-harming or suicidal thoughts.

If you or someone you know has symptoms of depression, trained therapists are available that specialize in topics associated with depression and mood disorders. A qualified mental health practitioner can assist in treating symptoms of major depression and developing coping strategies.

If you are simultaneously experiencing depression with a co-occurring substance use disorder, treatment is available. At The Recovery Village, a staff of professionals provides a number of treatment programs for substance use and co-occurring disorders. Call and speak with a representative to learn more about which treatment program could work for you.

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Editor – Jennifer Kopf
Jennifer Kopf is a Florida-based writer who likes to balance creative writing with helpful and informative pieces. Her passion for helping people has translated into writing about the importance of treatment for substance use and mental health disorders. Read more
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Medically Reviewed By – Tracy Smith, LPC, NCC, ACS
Tracy Smith is a Licensed Professional Counselor, a Nationally Certified Counselor, an Approved Clinical Supervisor, and a mental health freelance and ghostwriter. Read more
Medical Disclaimer

The Recovery Village aims to improve the quality of life for people struggling with substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare providers.