What’s the Difference Between Cyclothymia and Dysthymia?

Cyclothymia is characterized by frequent fluctuations in mood, with periods of hypomanic symptoms (elevated or irritable mood, increased energy) alternating with periods of depressive symptoms (sadness, hopelessness).

These changes in mood are less severe than those seen in bipolar disorder but last for extended periods, often lasting for at least 2 years.

Cyclothymia is estimated to affect 0.4%–1% of the population and has an equal male-to-female ratio. But, in certain clinical settings, the prevalence rates may be higher, with some surveys reporting rates as high as 5%.

Cyclothymia symptoms

The specific symptoms of cyclothymia can vary among individuals but typically include:

• hypomanic symptoms:
  • elevated or irritable mood
  • increased energy and activity levels
  • racing thoughts and rapid speech
  • decreased need for sleep
  • engaging in risky behaviors or impulsivity
  • feeling excessively confident or grandiose
• depressive symptoms:
  • persistent sadness or feelings of emptiness
  • loss of interest or pleasure in activities
  • changes in appetite and weight (increase or decrease)
  • sleep disturbances (insomnia or excessive sleep)
  • fatigue or loss of energy
  • feelings of worthlessness or guilt
  • difficulty concentrating or making decisions
  • recurrent thoughts of death or suicidal ideation

Dysthymia, or persistent depressive disorder (PDD), is a chronic form of depression characterized by persistent low mood and a lack of interest or pleasure in daily activities.

Symptoms are generally less severe than those of major depression but are more enduring, typically lasting for at least 2 years.

Dysthymia isn’t fully understood, and its diagnostic criteria are still subject to ongoing development. It was previously regarded as a personality disorder, but it’s now more accurately seen as a fluctuating state that can potentially change over time.

An estimated 1.5% of adults (more than 3 million) in the United States live with dysthymia. It affects more females (1.9%) than males (1%).

Dysthymia symptoms

The symptoms of dysthymia may include:

• persistent depressed mood
• lack of interest or pleasure
• changes in appetite
• sleep disturbances
• fatigue or lack of energy
• low self-esteem
• poor concentration or difficulty making decisions
• hopelessness

Cyclothymia is characterized by alternating periods of hypomanic symptoms and depressive symptoms, while dysthymia is marked by a chronic, persistent low mood without distinct episodes of elevated mood.

How to tell cyclothymia and dysthymia apart

While the depressive symptoms in cyclothymia and dysthymia may look similar, only cyclothymia features periods of elevated mood.

Cyclothymia is classified under bipolar mood disorders in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition, text revision (DSM-5-TR).

The criteria for cyclothymia include:

• Numerous periods of hypomanic symptoms and depressive symptoms must be present for at least 2 years (1 year for children and adolescents).
• During this period, the symptoms must not meet the criteria for a major depressive episode, manic episode, or hypomanic episode.
• The symptoms of hypomania and depression should persist for most of the time, with brief periods of normal mood lasting no longer than two months.
• The symptoms cause significant distress or impairment in social, occupational, or other important areas of functioning.

The diagnostic criteria for dysthymia (PDD) include:

• A depressed mood must be present most of the day, for more days than not, for at least 2 years (1 year for children and adolescents).
• During this period, the individual must experience at least two of the following symptoms: poor appetite or overeating, insomnia or hypersomnia, low energy or fatigue, low self-esteem, poor concentration or difficulty making decisions, and feelings of hopelessness.
• The symptoms don’t disappear for more than 2 months at a time.
• The symptoms cause significant distress or impairment in social, occupational, or other important areas of functioning.

Research suggests that bipolar disorders, including cyclothymia, may involve a combination of the following:

• Genetic factors: Cyclothymia has a genetic component, with a higher likelihood of developing the disorder if there’s a family history of mood disorders or bipolar disorder. There’s a high concordance rate of 57% among identical twins.
• Neurotransmitter dysregulation: Imbalances in neurotransmitters, particularly serotonin, dopamine, and norepinephrine, are thought to contribute to the development of cyclothymia.
• Environmental factors: Stressful life events, childhood trauma, and chronic stress can increase the risk of developing cyclothymia.
• Personality factors: A tendency toward negative thinking may contribute to the development of emotional dysregulation and instability in bipolar disorders.

Risk factors for dysthymia include the following:

• Genetic factors: Dysthymia may have a genetic component, with a higher risk when there’s a family history of mood disorders or depression.
• Early life experiences: Adverse childhood experiences, such as trauma, neglect, or unstable family environments, may increase the likelihood of developing dysthymia.
• Neurochemical imbalances: Imbalances in neurotransmitters, particularly serotonin, have been implicated in dysthymia.
• Chronic stress: Prolonged exposure to chronic stressors can contribute to the development of dysthymia.
• Personality factors: Certain personality traits, such as low self-esteem, negative thinking patterns, and pessimism, may increase the risk of dysthymia.
• Brain differences: Evidence suggests that people with dysthymia, or PDD, have significant volume reductions in certain brain areas associated with depression, including the frontal regions (such as the anterior cingulate and orbitofrontal cortex) and the hippocampus.

Cyclothymia treatment:

• Psychoeducation: A mental healthcare professional will provide information about the disorder, its symptoms, and the importance of treatment compliance.
• Medication: Mood stabilizers like valproate, lamotrigine, and lithium are often used as first-line treatments. Atypical antipsychotics can be used as monotherapy or in combination with mood stabilizers.
• Cognitive behavioral therapy (CBT): CBT has shown effectiveness in managing cyclothymia symptoms and addressing maladaptive thoughts and behaviors.
• Individualized approach: Treatment plans should be tailored to your specific needs, adjusting interventions as necessary.

Dysthymia treatment:

• Psychoeducation: It’s important you’re informed about dysthymia, its symptoms, and the importance of seeking treatment.
• Medication: Antidepressant medications, such as selective serotonin reuptake inhibitors (SSRIs), are commonly prescribed to alleviate depressive symptoms. Other classes of antidepressants may also be considered.
• Psychotherapy: Various forms of therapy, including CBT, interpersonal therapy, and psychodynamic therapy, have been found effective in treating dysthymia.

Cyclothymia and dysthymia are subthreshold mood disorders, which means that the symptoms experienced don’t fully meet the diagnostic criteria for major mood disorders such as bipolar disorder or MDD.

Despite not meeting the full criteria, these conditions can have a significant impact on daily living, causing impaired functioning and a decreased quality of life.

If you’re experiencing symptoms associated with cyclothymia or dysthymia, consider reaching out to a healthcare professional for a comprehensive evaluation and to discuss appropriate treatment options.