Sharing my notes, hoping to spread valuable information using simple terms and practical examples.

Disclaimer: The information on this post is not intended to diagnose, treat or evaluate a condition. It is for informative purpose only, for individuals seeking general information.

Everyone feels down or euphoric from time to time, but this is different from having a mood disorder such as major depressive disorder or bipolar disorder.

Mood disorders are extended periods of depressed, euphoric, or irritable moods that in combination with other symptoms cause the person significant distress and interfere with his or her daily life, often resulting in social and work issues.

Mood Disorders

Major Depressive Episode (Depression)

A major depressive episode (MDE) refers to symptoms that co-occur for at least two weeks and cause significant distress or impairment in functioning, such as interfering with work, school, or relationships.

Core symptoms include feeling down or depressed or experiencing anhedonia—loss of interest or pleasure in things that one typically enjoys. According to the fifth edition of the Diagnostic and Statistical Manual (DSM-5; APA, 2013), the criteria for an MDE require five or more of the following nine symptoms, including one or both of the first two symptoms, for most of the day, nearly every day:

1. depressed mood
2. diminished interest or pleasure in almost all activities
3. significant weight loss or gain or an increase or decrease in appetite
4. insomnia or hypersomnia
5. psychomotor agitation or retardation
6. fatigue or loss of energy
7. feeling worthless or excessive or inappropriate guilt
8. diminished ability to concentrate or indecisiveness
9. recurrent thoughts of death, suicidal ideation, or a suicide attempt

These symptoms cannot be caused by physiological effects of a substance or a general medical condition (e.g., hypothyroidism).

One of the main differences from Bipolar Disorder is that in depression there is no manic or “up” episodes.

Types of Depression are major depressive disorder (MDD) and persistent depressive disorder (PDD; dysthymia). Criteria for PDD are feeling depressed most of the day for more days than not, for at least two years.

At least two of the following symptoms are also required to meet criteria for PDD:

1. poor appetite or overeating
2. insomnia or hypersomnia
3. low energy or fatigue
4. low self-esteem
5. poor concentration or difficulty making decisions
6. feelings of hopelessness

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Bipolar Mood Disorders

There are two episodes in Bipolar Disorder – hence the term bipolar.

1. Depressive Episode
2. Manic Episode

The criteria for manic episode is a distinct period of abnormally and persistently euphoric, expansive, or irritable mood and persistently increased goal-directed activity or energy.

Symptoms of mania include;

1. inflated self-esteem or grandiosity
2. increased goal-directed activity or psychomotor agitation
3. reduced need for sleep
4. racing thoughts or flight of ideas
5. distractibility
6. more talkative than usual
7. excessive involvement in risky or reckless behaviors (drugs, money, sex)

Three major types of BDs are described by the DSM-5 (APA, 2013). Bipolar I Disorder (BD I), which was previously known as manic-depression, is characterized by a single (or recurrent) manic episode. A depressive episode is not necessary but commonly present for the diagnosis of BD I. Bipolar II Disorder is characterized by single (or recurrent) hypomanic episodes and depressive episodes. Another type of BD is cyclothymic disorder, characterized by numerous and alternating periods of hypomania and depression, lasting at least two years. To qualify for cyclothymic disorder, the periods of depression cannot meet full diagnostic criteria for an MDE; the person must experience symptoms at least half the time with no more than two consecutive symptom-free months; and the symptoms must cause significant distress or impairment.

In simple terms – Bipolar is characterized by mood swings that fluctuate between depressing lows and manic highs.

It is important to note that the DSM-5 was was published in 2013, and findings based on the updated manual will be forthcoming. Consequently, the research presented below was largely based on a similar, but not identical, conceptualization of mood disorders drawn from the DSM-IV (APA, 2000).