Cyclothymic disorder
Cyclothymic disorder is a chronic bipolar-spectrum illness with numerous hypomanic-range and depressive-range periods that never meet full episode criteria for at least 2 years (1 year in children). Diagnosis is clinical; first-line treatment is cognitive behavioral therapy (CBT), with divalproex sodium started when functioning is impaired.
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What this article covers
- Overview
Definition: cyclothymic disorder is a chronic bipolar-spectrum illness with numerous periods of hypomanic-range symptoms that never meet full hypomanic episode criteria, alternating with numerous…
- Epidemiology
Category-level risk: family history is described as a risk factor across bipolar and related disorders, the category that includes cyclothymic disorder along with bipolar I and bipolar II disorder.
- Risk factors
Family history of bipolar spectrum illness: the strongest recognized risk association for bipolar and related disorders as a category, applying to cyclothymic disorder as one of its three subtypes.
- Pathophysiology
Dimensional, not categorical: cyclothymic disorder is defined descriptively as chronic subthreshold mood instability rather than by a distinct mechanism; the hypomanic-range and depressive-range…
- Clinical features
Diagnostic criteria (the core of the diagnosis): numerous periods of hypomanic-range symptoms not meeting full hypomanic episode criteria and numerous periods of depressive-range symptoms not meeting…
- Differential diagnosis
Bipolar I disorder: requires a full manic episode, elevated or irritable mood for at least 1 week (or any duration if hospitalization is required) with the DIG FAST features and possible psychotic…
- Diagnosis
What confirms the diagnosis: cyclothymic disorder is a clinical diagnosis, established from a longitudinal history showing numerous hypomanic-range periods and numerous depressive-range periods…
- Management
First, assess and address safety: if there is any suicidal ideation or danger to self or others, hospitalize on a psychiatric ward before addressing maintenance therapy.
- Complications
Reclassification to bipolar I or bipolar II disorder: a later full manic, hypomanic, or major depressive episode changes the diagnosis, since cyclothymic disorder is defined by symptoms that never reach those thresholds.
- Prognosis
Chronic course: the illness is defined by symptoms persisting at least half the time over a minimum 2-year span, and mood episode frequency tends to increase with age across the bipolar and related disorders spectrum.
- Prevention
Screen before prescribing antidepressants: administer the Mood Disorder Questionnaire in any patient presenting with depressive symptoms before starting an antidepressant, to avoid precipitating a…
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Related articles
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