List of mood disorders
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Comprehensive Overview of Mood Disorders
Introduction to Mood Disorders
Mood disorders, also known as affective disorders, are a category of mental health conditions primarily characterized by significant disturbances in a person's mood. These disorders can manifest as episodes of depression, mania, or a combination of both, significantly impacting an individual's daily functioning and quality of life .
Classification of Mood Disorders
Major Depressive Disorder (MDD)
Major Depressive Disorder is characterized by persistent and intense feelings of sadness and despair. Individuals with MDD experience a range of symptoms including loss of interest in activities, changes in appetite and sleep patterns, and difficulty concentrating. These symptoms must be present for at least two weeks to meet the diagnostic criteria 47.
Bipolar Disorders
Bipolar disorders are marked by alternating periods of depression and mania. There are two main types:
- Bipolar I Disorder: Defined by manic episodes that last at least one week, often accompanied by depressive episodes.
- Bipolar II Disorder: Characterized by hypomanic episodes (less severe than manic episodes) and major depressive episodes 45.
Cyclothymic Disorder
Cyclothymic disorder involves chronic fluctuating moods involving periods of hypomanic symptoms and periods of depressive symptoms that are not severe enough to qualify as major depressive episodes or manic episodes .
Dysthymic Disorder (Persistent Depressive Disorder)
Dysthymic disorder is a chronic form of depression with symptoms that are less severe than those of major depression but last for a longer period, typically at least two years 110.
Subtypes and Specifiers
Melancholic Features
This specifier is used when a person experiences a loss of pleasure in almost all activities or a lack of reactivity to usually pleasurable stimuli, along with other symptoms such as early morning awakening, significant weight loss, or excessive guilt .
Atypical Features
Atypical depression includes mood reactivity (mood brightens in response to positive events) and significant weight gain or increase in appetite, among other symptoms .
Seasonal Pattern
This specifier applies to mood disorders that have a seasonal pattern, typically worsening in the winter months and improving in the summer .
Rapid Cycling
In bipolar disorder, rapid cycling is defined as having four or more mood episodes (mania, hypomania, or depression) within a year .
Comorbidity with Personality Disorders
Mood disorders often co-occur with personality disorders. For instance, individuals with bipolar disorder frequently exhibit comorbid Cluster B (dramatic, emotional, or erratic) and Cluster C (anxious or fearful) personality disorders. Major depressive disorder and dysthymic disorder are commonly associated with Cluster C personality disorders .
Genetic and Biological Factors
Research indicates a significant genetic overlap between major depressive disorder and bipolar disorder, suggesting shared molecular genetic bases. Genome-wide association studies have identified several loci associated with these mood disorders, highlighting both shared and distinct genetic factors .
Conclusion
Mood disorders encompass a range of conditions characterized by significant mood disturbances, including major depressive disorder, bipolar disorders, cyclothymic disorder, and dysthymic disorder. These disorders can present with various specifiers and often co-occur with personality disorders. Understanding the genetic and biological underpinnings of mood disorders can aid in developing more effective treatments and interventions.
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