Your Guide to Persistent Depressive Disorder (Dysthymia)

Medically Reviewed By Jeffrey Ditzell, DO
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Persistent depressive disorder (PDD), or dysthymia, is a type of chronic depression wherein a person experiences a low-level depressed mood over an extended period of time. A person with PDD may be able to carry out their daily activities, but they may also experience frequent episodes of irritability, stress, and difficulty sleeping.

Around 3–6% of people have PDD. However, some individuals may not realize that they have a health condition, as they may perceive their symptoms to be a part of their personality. Symptoms of PDD typically appear earlier in life.

Someone with PDD may experience low self-esteem or feelings of inadequacy. The condition can also result in difficulty thinking, social withdrawal, and a general loss of interest. PDD can also occur alongside periods of major depression.

Read on to learn more about the symptoms of PDD. This article also covers its causes and treatment options.

What is persistent depressive disorder?

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PDD is a long-term, chronic form of depression. A person with PDD may lose interest in their usual activities, and they may have low self-esteem or a general feeling of inadequacy. Symptoms can last years and interfere with work, relationships, and daily life.

An individual with PDD may come across as being unenthusiastic or downbeat. Some people may not recognize that they are experiencing depression, especially if their symptoms have been present since childhood or adolescence.

Visit our depression hub here.

Vs. major depressive disorder

Different types of depression have similar symptoms, including feeling low, struggling to concentrate, and experiencing feelings of hopelessness or low self-esteem. However, they may appear at different times or in different severities.

PDD can begin in childhood or early adulthood. As the symptoms can linger, the person may not realize that they are experiencing a form of depression. PDD tends to last at least 2 years.

Contrastingly, major depressive disorder symptoms may appear to be more severe, but they do not last as long. An episode of major depressive disorder typically lasts around 2 weeks or longer.

Around 75% of people with PDD will experience at least one episode of major depressive disorder. This is known as “double depression.”

Is persistent depressive disorder a disability?

Because the symptoms of PDD are chronic but usually not as severe as other types of depression, the condition may not be considered a disability.

However, PDD may be seen as a disability if you are able to show that it severely affects your ability to carry out your daily activities. It may also be seen as a disability if you have extended periods of severe symptoms.

What are the symptoms of persistent depressive disorder?

An individual with PDD tends to experience low moods and difficulties carrying out their daily tasks. Other examples of PDD symptoms include:

  • feeling inadequate
  • having low self-esteem
  • feeling irritable or angry
  • feeling guilty
  • losing interest in doing things
  • withdrawing from social interactions
  • having tiredness or chronic fatigue
  • having reduced productivity
  • having difficulty thinking or concentrating
  • having a poor memory
  • having difficulty making decisions

Symptoms of depression tend to be the same or very similar regardless of the type of depression. However, the severity and duration of the symptoms can help determine which type of depression someone has.

PDD symptoms last for a number of years, and they can begin in childhood or early adulthood. Although the symptoms may not be as severe as they are with other variations of depression, such as major depressive disorder, they do continue for extended periods of time.

Who can experience persistent depressive disorder?

Anybody of any age can experience symptoms of PDD. An adult may receive a PDD diagnosis if they have had symptoms for at least 2 years, with no longer than 2 months without symptoms during that period. For children and adolescents, symptoms need to be present for 1 year.

At least 3% of the population of the United States experiences PDD. There are typically twice as many cases among females than males.

What causes persistent depressive disorder?

There is no known cause of PDD. However, it is possible that issues with chemicals in the brain, including serotonin, may play a role. As serotonin influences positive mood and emotion, having a lack of serotonin may cause low moods.

There are risk factors that make an individual more likely to develop PDD. These include:

  • experiencing loss or grief
  • having feelings of stress
  • having a long-term illness
  • experiencing child abuse or abuse from a partner
  • having a family history of depression
  • having a history of substance misuse
  • sustaining a brain injury

When should I contact a doctor?

Contact a doctor as soon as you begin to experience symptoms of depression or as soon as you think that you might be feeling depressed. They will be able to rule out any underlying conditions that may be contributing to your symptoms and refer you to a mental health specialist.

Get tips on talking with your doctor about depression treatments here.

Diagnosing persistent depressive disorder

In order for a doctor to diagnose PDD, a depressed mood needs to be present for 2 years for an adult or 1 year for a child or adolescent. A child or adolescent may present irritability instead of depression. During that time, there must not be a symptom-free period that lasts longer than 2 months.

The person must also experience at least two of the following symptoms:

  • feelings of hopelessness
  • low self-esteem
  • fatigue or low energy
  • an inability to concentrate or make decisions
  • poor appetite or overeating
  • insomnia or falling asleep during the day

Following a diagnosis of PDD, your doctor will be able to refer you to a mental health specialist.

Treatment options for persistent depressive disorder

Treatments may differ depending on your individual circumstances, but treatment will generally include therapy, medication, or both. Most people respond better to treatment when they take a suitable medication and undergo therapy.

Antidepressant medications include selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs). Both can help increase serotonin levels in the brain. Serotonin helps with positive mood and emotion.

Therapy for depression can include cognitive behavioral therapy (CBT) and interpersonal therapy. CBT is a talking therapy that helps you understand your feelings and change the way you respond to them. Interpersonal therapy connects your depression to relationships with other people and helps you work through those emotions.

Learn more about these treatment options with our guides to CBT and understanding antidepressants.


PDD is a form of chronic depression wherein a person experiences a low-level depressed mood over an extended period of time. It is also known as dysthymia.

Symptoms include feelings of inadequacy, a loss of interest, an inability to make decisions, and difficulty sleeping. Many people can go about their day while experiencing these symptoms. People who have had the condition since adolescence may not know that they are experiencing mental ill-health.

A doctor can diagnose PDD once an adult has had a depressed mood for at least 2 years or a child or adolescent has had similar symptoms for at least 1 year. Following diagnosis, treatments such as CBT and antidepressants can help with managing the condition.

Contact your doctor if you experience any symptoms of depression or feel that you may be experiencing PDD.

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Medical Reviewer: Jeffrey Ditzell, DO
Last Review Date: 2022 Mar 16
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