Bipolar Disorder

For BIO 443: Drugs and Disease

Presented by: Abby Normal

Bipolar Disorder …

• Also known as Manic Depression

• Results in pathological mood swings from mania to depression

• These mood swings occur spontaneously

Manic Phase

• Characterized by– Hyperactivity– Over-involvement– Inflated self-esteem– Easily distracted– Little need for sleep

• Hypomania– Less severe– Does not cause

significant distress

Depressive Phase

• Characterized by – Sluggishness– Loss of self-esteem– Withdrawal– Sadness– Excess need for sleep– Risk of suicide

Epidemiology

• Overall affects men and women equally

• Affects about 1% of adults in the US

• Usually appears between 15-25 years

• No difference among racial groups

Types of Bipolar Disorder

• Bipolar I– More time in depressed state– Long periods of normality

• Bipolar II– Long episodes of depression, occasional

hypomania– Virtually no time of wellness

Types of Bipolar Disorder

• Cyclothymia– Many episodes of hypomania

– Occasional mild depression

• Mixed states– Signs of depression and mania at same time

• Rapid cycling– Many cycles of mania and depression each year

– Four or more episodes a year

Childhood Onset Bipolar Disorder

• Affects those younger than age 15

• Often involves mixed episodes

• Extreme amounts of cycling – many times a day

• Bipolar is more severe when present in children and harder to treat

Genetics

• Environment can trigger it and affect the severity of the disorder

• No single genetic basis• Most likely complex genetic disorder• One possibility … inherited variation in serotonin

transporter gene may play a role

Serotonin

• Low levels can set off impulsive and aggressive behaviors, depression

• Low levels can also lead to inability to handle powerful emotions

Pet Scan for serotonin

Person in depressive episode Healthy individual

Treatments

• Older Mood Stabilizers– Lithium

– Valproic Acid

• New Mood Stabilizers– Lamictal

– Neurotonin

– Topamax

Old Mood Stabilizers

• Have been shown to reduce mania and slow cycling

• Often require blood levels frequently for monitoring

• Many side effects– Nausea, vomiting– Weight gain or loss– Acne problems– Hair loss– Affects balance

Lithium and Valproic Acid

• Slow action suggest that they may regulate gene expression

• Thought to inhibit protein kinase C which regulates neurohormonal release

• Interferes with the reuptake of serotonin and norepinephrine

New Mood Stabilizers

• Have been shown to be effective in adults• Effects are not known in children yet• Mechanisms are unknown• Effects are quicker• Side effects appear less• May have long term side effects that are not

known of yet

Future?

• Researchers believe they are coming closer to finding a genetic link and mechanism of the disorder

• This could lead to better drugs that would act specifically for bipolar disorder

Questions?