Persistent Depressive Disorder

Persistent Depressive Disorder

If you’ve heard the term “persistent depressive disorder,” you may’ve wondered whether it is a phenomenon from pop psychology or a real diagnosable condition. While persistent depressive disorder (PDD) may not be as debilitating as major depressive disorder, it is a legitimate psychological disorder and one that is highly treatable.

Defining Persistent Depressive Disorder (PDD)

PDD is a form of major depression, but it isn’t short-lived. It is, therefore, less severe but more chronic than major depression. Those diagnosed (or undiagnosed) with PDD experience it continuously and for long periods.

Some of the features and characteristics that describe PDD include that:

  • It can be a severe and disabling disorder.
  • Mostly, it is depression that is mild to moderate.
  • It shares many symptoms with other types of clinical depression.
  • It is also called “dysthymia.”

The Definition of Persistent Depressive Disorder and Its Origins

Where did the definition of PDD originate? Robert Spitzer, a New York psychiatrist, coined the term in the 1970s as replacement terminology for “depressive personality.” Other sources say that the persistent depressive disorder definition combines earlier diagnoses: chronic major depressive disorder and dysthymia (or dysthymic disorder).

Symptoms of PDD: Characteristics and Duration

Symptoms of PDD are varied. They also tend to vary by individual. This is influenced by many factors, including the presence of other medical or mental health conditions, prior depression history, and how long the individual has been experiencing PDD.

Most Common Symptoms of PDD

While the list is lengthy, the most common symptoms of PDD include:

  • Individuals with PDD experience a profoundly dark, low, and sad mood most days for the entire day.
  • Even if there are lapses between the deep, dark sadness, it occurs more days than the individual feels free of the bleakness.
  • The symptoms of PDD can sometimes disappear, only to recur.
  • This mild depression can last for two years or longer.
  • Individuals experiencing symptoms of PDD may lose interest in daily activities, especially those they once enjoyed.
  • Furthermore, they avoid participating in social activities.

Other common symptoms of PDD include:

  • Frequent irritability
  • Sleep disruptions and problems staying asleep through the night
  • Feeling guilt and worry about the past
  • Lowered self-esteem
  • Lack of energy with no readily explainable cause
  • Feeling tired all the time
  • Poor concentration
  • Difficulty with decision-making
  • Eating difficulties: overeating or having a poor appetite

Risk Factors and Causes of Persistent Depressive Disorder

What are the causes of persistent depressive disorder? Any discussion of persistent depressive disorder definition typically includes the statement that, currently, there is no known exact cause for this mental health disorder. Research into the psychiatric disorder’s causes is ongoing. Yet, like major depressive disorder, the root causes may be a combination of several causes, including:

  • Genetic or inherited traits. Those whose blood relatives have PDD are more likely also to have the disorder. Generally, this includes blood relatives of the first degree, such as a sibling or parent. Research continues to identify the particular genes causing depression.
  • Brain chemistry changes. According to research, changes in the brain’s neurotransmitters (naturally occurring chemicals in the brain) may play a significant role in developing depression and treating the disorder. Neurotransmitters control the brain’s activities.
  • Serotonin Imbalance. Some researchers believe that a serotonin imbalance in the brain (serotonin is a neurotransmitter) may be among the causes of depression, including PDD. Serotonin imbalance influences mood, and low mood is one of the common PDD symptoms.

There are several possible serotonin problems:

  • Low serotonin brain cell production
  • Few or no receptor sites to receive the serotonin
  • Serotonin’s inability to reach receptor sites
  • Tryptophan shortage (serotonin is made from this chemical)
  • Differences in biology. There may be physical changes in the brains of those with persistent depressive disorder. While it is not known how such brain changes affect PDD, they may one day prove helpful in identifying the causes of the disorder.
  • Significant or traumatic life events. Similar to major depression, highly traumatic life events may trigger the onset of persistent depressive disorder in some individuals. These life events may include a loved one’s death, mounting or disastrous financial difficulties, or a constant elevated stress level.

Treatment Approaches for Persistent Depressive Disorder

For those experiencing this disabling disorder, which typically begins in childhood, there are effective treatment options for PDD. As with major depressive disorder, PDD treatment is a challenge. Treatment usually combines psychotherapy and medication.

Diagnosing PDD is critical. It is the long duration of the symptoms, not their intensity. Specifically, this includes experiencing a low mood and other depressive symptoms for two years or more.

Furthermore, a full-blown major depression episode can result from symptoms of PDD. Also, if someone already has PDD, their chances of it developing into major depression are greater than average.

The goal of PDD treatment is a reduction in how long the low mood lasts and symptom intensity. Yet, someone who experiences a low mood but isn’t diagnosed with PDD can still seek treatment to cope with symptoms.


Treatment with antidepressants, specifically selective serotonin reuptake inhibitors (SSRIs), has been the first-line approach for treating major depression. As such, they are also used to treat PDD.

SSRIs include fluoxetine, paroxetine, citalopram, sertraline, fluvoxamine, and escitalopram. These medications have fewer adverse effects than tricyclic antidepressants (TCAs) and are as effective in treating major depression.

Other medications used to treat PDD include serotonin-norepinephrine reuptake inhibitors (SNRIs), such as venlafaxine, buproprion, and mirtazapine. Older antidepressants may be prescribed for individuals with PDD who do not respond well to the newer drugs. These include TCAs and monoamine oxidase inhibitors (MAOIs).


Psychological counseling, or psychotherapy, can help individuals better manage persistent depressive disorder. During counseling, individuals learn about PDD and how to cope with ongoing symptoms, while prescribed medications seek to reduce low mood duration and symptom intensity.

Cognitive-behavioral therapy (CBT) is a proven form of structured psychotherapy that may be used to treat PDD. CBT targets distorted cognitions and irrational beliefs that allow symptoms to continue. The therapist does this by challenging and then reversing those cognitions and beliefs. Other forms of CBT that may be effective in treating PDD include acceptance and commitment therapy (ACT), computerized CBT (CCBT), and schema therapy.

Problem-solving therapy is a combination of interpersonal and cognitive elements. The therapist focuses on negative situation assessment and strategies to overcome problems.

Psychodynamic therapy makes use of short- and long-term interventions. It focuses on conflicts around shame, early childhood difficulties and problems, and repressed impulses.

MBCT, while relatively recent, combines mindfulness-based stress reduction (MBSR) with CBT elements. The approach is often helpful as a possible alternative to taper down antidepressant medication use without increased risk of relapse.

Group therapy and marital and family therapy may also be beneficial to treat some of the aspects of PDD.

Other Psychological Interventions as Treatment Options for PDD

Psychoeducation and physical exercise are considered recommended approaches to treat PDD.

Psychoeducation seeks to inform individuals about PDD, its symptoms, triggers, and its management. They also learn about medication, treatment duration, and relapse risk. Numerous studies have shown psychoeducation improves treatment and functioning in those with PDD.
Exercise is considered an adjunct approach to treating PDD. Regular physical activity can calm or alleviate symptoms and reduce relapse while improving quality of life.

Somatic Therapies

Other potential PDD treatments may include somatic therapies, such as ECT, deep brain stimulation (DBS), magnetic seizure therapy, vagus nerve stimulation (VNS), transcranial direct current stimulation (tDCS), repetitive transcranial magnetic stimulation (rTMS), and luxtherapy (or phototherapy).

Lifestyle Strategies and Coping Mechanisms

What are some of the ways individuals can cope with the symptoms of PDD? Individuals challenged by PDD can improve their general well-being and quality of life by incorporating healthy lifestyle strategies and coping mechanisms:

  • Engage in good self-care. To cope with PDD, do things that are relaxing and boost well-being, such as yoga, deep breathing, meditation, and massage. Eat nutritious meals, get regular exercise, and good-quality sleep.
  • Develop and maintain a strong support network. You need people to talk with when things get tough. Regular check-ins with trusted friends or family or members of a depression support group can be invaluable to encourage and motivate you in difficult times.
  • Create and pursue realistic goals. You always want to keep moving forward, doing things you want for your future. This helps with feeling in control and improves self-esteem.
  • Do activities you love. If you enjoy outdoor sports or activities, do them as often as possible. The same holds for fun activities, like reading, gardening, exercise, dance, movies, music, and hobbies.
  • Keep up with treatment. To overcome and manage PDD, stick with your treatment. You can improve your quality of life and everyday functioning by combining therapy, medications, alternative and adjunct therapies, healthy lifestyle strategies, and coping mechanisms.