The most prevalent psychiatric disorders.

Lifetime prevalence of any anxiety: 25%.

Lifetime prevalence of social phobia and simple phobia is higher than that of panic disorder, agoraphobia, and generalized anxiety disorder.

More likely to have anxiety disorders: Women; first-degree relatives of patients with anxiety disorders.

Less likely to have anxiety disorders: Men; higher socioeconomic status.

Abnormalities in one carbon cycle metabolism are associated with clinical depression, presumably due to deficiency in monoamine neurotransmitters.

SAMe is the major donor of methyl groups in the synthesis of monoamine neurotransmitters, including serotonin, norepinephrine, and dopamine.

Methylfolate is an important element in replenishing SAMe.

Folic acid is the precursor of methylfolate.

The conversion of folic acid to methylfolate relies on an enzyme, 5,10-methylene tetrahydrofolate reductase (MTHFR).

MTHFR polymorphism may decrease the availability of methylfolate.

Oral methylfolate and SAMe may help replenish SAMe, and have been suggested as supplements for treatment of depression.

Symptoms that indicate complication of major depression:

Guilt;

Psychomotor retardation;

Hallucination;

Preoccupation with worthlessness;

Symptoms lasting longer than 2 months.

Uncomplicated bereavement may present with extreme sadness, crying spells, and anger toward God; however, it does not present with the symptoms mentioned above.

Mood symptoms must appear after the onset of substance use;

Mood symptoms may appear during intoxication or withdrawal.

Mood symptoms must exceed those usually associated with intoxication or withdrawal, and must be severe enough to warrant clinical attention for a separate diagnosis.

Onset after age 40.

Lack of familial history.

Lack of triggering events.

Lack of avoidance behavior.

Poor response to anxiolytic agents.

Anxiety neurosis is a term coined by Sigmund Freud.

According to Freud, an escalation in sexual tension leads to an increase in libido and desire for intercourse. When a sexual outlet is unavailable, the unreleased tension produces neurosis.

The symptoms described by Freud are similar to those for panic disorder as defined in DSM-IV-TR.

Mitral valve prolapse was believed to be associated with panic disorder, and historically has raised great research interest.

However, extensive research has found mitral valve prolapse to be unrelated to panic disorder.