Mood Disorder

Mood is defined as a pervasive and sustained feeling tone that is endured internally, and that impacts nearly all aspects of a person’s behavior in the external world. Mood disorders or affective disorders are described by marked disruptions in emotions (severe lows called depression or highs called hypomania or mania). These are common psychiatric disorders leading to an increase in morbidity and mortality.

According to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), mood disorders have been broadly categorized as bipolar disorders and depressive disorders. Bipolar disorders are further categorized as bipolar I, bipolar II, cyclothymic disorder, bipolar and related disorder to another medical condition, substance/medication-induced bipolar and related disorder, other specified bipolar and related disorder, and unspecified bipolar and related disorder.

1. Bipolar I disorder is defined as a syndrome in which a complete set of mania symptoms (elevated mood with three or more of the following symptoms- increased goal-directed activity, grandiosity, a diminished need for sleep, distractibility, racing thoughts, increased/pressured speech, and reckless behaviors) has occurred lasting for at least one week or required hospitalization. If the mood is irritable instead of elevated, four or more of the aforementioned symptoms are needed to meet the criteria for a manic episode.

1. Bipolar II disorder consists of current or past major depressive episodes interspersed with current or past hypomanic periods of at least four days duration.

1. Cyclothymia is defined as a subthreshold bipolar trait or temperament with low-grade affective manifestations of the sub-threshold major depression and mild hypomania. It is diagnosed in adults who experience at least 2 years of both hypomanic and depressive periods without ever meeting the criteria for mania, hypomania, or major depression. For a child or an adolescent to be diagnosed with cyclothymia, these episodes should last over 1 year.

1. Hypomania is defined as a non-psychotic, milder, or subthreshold manic state of short duration lasting for at least four consecutive days and without marked social and occupational impairment. It requires elevated mood with (three or more symptoms) or irritable mood (with four or more of the following symptoms) - increased goal-directed activity, grandiosity, a diminished need for sleep, distractibility, racing thoughts, increased/pressured speech, and reckless behaviors. According to the International Classification of Diseases 11th Revision (ICD-11), cyclothymia and hypomania are considered as a prodrome of bipolar disorders, and per DSM 5, hypomania is a component of bipolar II disorder.

Major depressive disorder is diagnosed by the presence of 5 out of the 9 symptoms of sad mood, insomnia, feelings of guilt, decreased energy levels, decreased concentration, decreased appetite, decrease in pleasurable activities (anhedonia), increased or decreased psychomotor activity, and recurrent suicidal ideation/acts of self-harm/suicide attempt existing over a period of 2 weeks.

Three new depressive disorders have been incorporated under mood disorders in DSM-5:

1. Disruptive mood dysregulation disorder (DMDD) is seen in children and adolescents with frequent anger outbursts and irritability out of proportion to the situation

2. Persistent depressive disorder (PDD) or dysthymia, which means a depressed mood that is not severe enough to meet the criteria for major depression. PDD is defined as the depressed mood for at least two years in adults and one year in children and adolescents

3. The premenstrual dysphoric disorder (PMDD) is characterized by irritability, anxiety, depression, and emotional lability occurring in a week before the onset of menses followed by resolution of the symptoms after onset.

Major depression episodes may precede or occur concurrently with persistent depressive disorder, and this is known as double depression.

Other depressive disorders include depressive disorder due to another medical condition, substance or medication-induced depressive disorder, other specified depressive disorder, and unspecified depressive disorder.