Mood Disorders

When you think of mood disorders, depression and bipolar disorder likely come to mind first. That's because these are common, severe illnesses and leading causes of disability. Depression and bipolar disorder can be emotionally crippling, making it difficult to live life to its fullest. Persistent Depressive Disorder, a newer diagnosis that consolidates chronic major depressive disorder and dysthymic disorder, is a condition where a person is depressed for at least 2 years.


Mood Disorders: What Is Persistent Depressive Disorder?

This mood disorder is a less severe form of depression. Although less extreme, Persistent Depressive Disorder causes chronic or long-lasting moodiness that ranges in severity. It is marked by a depressed mood for most of the day, for more days than not, for at least 2 years. In children and teens, moods can be irritable for at least 1 year to be called Persistent Depressive Disorder. 

Persistent Depressive Disorder can occur alone or with other psychiatric or mood disorders, although not with mania or hypomania. As with depression, PDD is more common in women than in men. A family history of mood disorders is not uncommon. This mood disorder tends to appear earlier than major depression, although it can begin anytime from childhood to later in life.

About 1.5% of U.S. adults have experienced PDD in the previous year. Its cause is not well understood. A combination of factors likely conspires to create this mood disorder. These factors may include:

  • Genetics
  • Abnormalities in the functioning of brain circuits involve in emotional processing
  • Chronic stress or medical illness
  • Isolation
  • Poor coping strategies and problems adjusting to life stresses

These factors can feed off each other. For example, if you always see "the glass as half empty," you may reinforce the symptoms of depression. And a chronic mood disorder can sensitize you to stress, further feeding your risk for depression.

Symptoms of Persistent Depressive Disorder

In addition to chronic low moods, common symptoms of this mood disorder include:

  • Feelings of hopelessness or helplessness
  • Trouble sleeping or daytime sleepiness
  • Poor appetite or eating too much
  • Poor concentration
  • Fatigue or low energy
  • Low self-esteem
  • Trouble concentrating or making decisions

A diagnosis of PDD in adults requires at least a two-year history of depressed mood for most of the day on most days, along with at least two of the symptoms noted above. Although some symptoms may overlap, you may be less likely to have weight or sleep changes with PDD than with depression. You may also tend to withdraw more and have stronger feelings of pessimism and inadequacy than with major depression.


Treatment for Persistent Depressive Disorder

Staying in a constant state of moodiness is no way to live. That's one reason to seek treatment. Another is that Persistent Depressive Disorder can also increase your risk for physical diseases. Yet another reason to pursue treatment? If left untreated, this mood disorder can develop into more severe depression. It can also increase your risk for attempting suicide.

Antidepressants , such as selective-serotonin reuptake inhibitors (SSRIs), serotonin norepinephrine reuptake inhibitors (SNRIs), or tricyclic antidepressants, are often used to treat PDD. Because you may need to continue treatment for a lengthy period, it's important to consider which medications not only work well but also ideally have few side effects. You may need to try more than one medication to find the one that works best. But know that it may take several weeks or longer to take effect. Successful treatment for chronic depression often takes longer than for acute (non-chronic) depression.

Take your medications as your doctor instructs. If they're causing side effects or still not working after several weeks, discuss this with your doctor. Don't suddenly stop taking your medications.

Doctors believe treatment for PDD is effective with a combination of antidepressants and psychotherapy. 

Specific kinds of talk therapy, such as cognitive behavioral therapy (CBT), psychodynamic psychotherapy, or interpersonal therapy (IPT), are known to be effective forms of psychotherapy that treat Persistent Depressive Disorder. A structured treatment lasting for a certain period of time, CBT involves recognizing and restructuring thoughts. It can help you change your distorted thinking. IPT is also a time-limited, structured treatment. Its focus is on addressing current problems and solving interpersonal conflicts. Psychodynamic psychotherapy involves exploring unhealthy or unsatisfying patterns of behavior and motivations that you may not be consciously aware of which could lead to feelings of depression and negative expectations and life experiences.

Some studies also suggest that aerobic exercise can help with mood disorders. This is most effective when done four to six times a week. But some exercise is better than none at all. Other changes may also help, including seeking social support and finding an interesting occupation. Used for patients with seasonal affective disorder, bright-light therapy may also help some people with Persistent Depressive Disorder.


Mood Disorders: What Is Cyclothymic Disorder?

Bipolar disorder causes severe, unusual shifts in mood and energy that affect your ability to do normal tasks at home, school, or work. Cyclothymic disorder is often thought of as a mild form of bipolar disorder.

With cyclothymic disorder, you have low-grade high periods (hypomanias) as well as brief, fleeting periods of depression that don't last as long (less than 2 weeks at a time) as in a major depressive episode. The hypomanias in cyclothymic disorder are similar to those seen in bipolar II disorder, and do not progress to full-blown manias. For example, you may feel an exaggerated sense of productivity or power, but you don't lose connection with reality. In fact, some people feel the "highs" of cyclothymic disorder are even enjoyable. They tend to not be as disabling as they are with bipolar disorder.

Up to 1% of the U.S. population -- equal numbers of men and women -- has cyclothymia. Its cause is unknown, but genetics may play a role; cyclothymia is more common in people with relatives who have bipolar disorder. Symptoms usually appear in adolescence or young adulthood. But because symptoms are mild, it is often difficult to tell when cyclothymia begins.

Symptoms of Cyclothymic Disorder

A diagnosis of cyclothymic disorder may result from simply describing symptoms like these:

  • Episodes that involve brief, recurrent periods of depression and, at other times, episodes of hypomania; this pattern of episodes must be present for at least 2 years.
  • Symptoms that persist, creating fewer than 2 symptom-free months in a row.

The episodes of cyclothymic disorder are often somewhat unpredictable. Either depression or hypomania can last for days or weeks, interspersed with a month or two of normal moods. Or, you may have no "normal" periods in between. In some cases, cyclothymic disorder progresses to full-blown bipolar disease.

Treatment for Cyclothymic Disorder

Some people with mild symptoms of cyclothymia are able to live successful, fulfilling lives. Others find their relationships troubled by depression, impulsive actions, and strong emotions. For these people, short-term medications may bring relief. However, cyclothymic disorder may not respond as well to medications as does bipolar disorder. A combination of mood stabilizers and psychotherapy is most effective. Mood stabilizers include antiseizure drugs such as lithium, Depakote, Tegretol, or Lamictal.

WebMD Medical Reference Reviewed by Smitha Bhandari, MD on February 21, 2018



MedlinePlus: "Dysthymia" and "Cyclothymia." 

American Academy of Family Physicians: "Dysthymic Disorder: When Depression Lingers." 

EMedicine: "Dysthymic Disorder." 

Depression and Bipolar Support Alliance: "Types of Depression."

WebMD Medical Reference: "Cyclothymia (Cyclothymic Disorder)." 

World Health Organization: "What Is Depression?"

National Institute of Mental Health: "Persistent Depressive Disorder."

American Academy of Family Physicians: "Persistent Depressive Disorder (PDD)."

BASC 3: "Persistent Depressive Disorder (Dysthymia)."

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