Problem 3
PART 1 LEARNING GOALS
What are the symptoms of bipolar disorders (BD) I and II as well as of cyclothymia?
How is the epidemiology of these disorders?
Which are the risk factors and the time course of these mental diseases?
CARVALHO – BIPOLAR DISORDER
- main characteristic bipolar disorders:
o the presence of recurring manic or hypomanic episodes that alternate with
depressive episodes
- Bipolar I:
o has to meet criteria of a manic episode at least once (manifestations of
overconfidence, grandiosity, talkativeness, extreme disinhibition, irritability,
decreased need for sleep and highly elevated mood)
o the manic episode may be followed by hypomanic or depressive episodes
(common but not required for diagnosis)
o psychotic symptoms such as delusions and hallucinations occur in up to 75%
of manic episodes
- Bipolar II is defined by:
o has to meet criteria for at least one hypomanic episode (hypomania is a
milder form of mania), and at least an episode of major depression
o there has never been a manic episode
- Cyclothymic disorder defined by:
o recurring depressive and hypomanic states, lasting for at least 2 years (for
adults), that do not meet the diagnostic threshold for a major affective
episode
,
, - onset of bipolar disorder typically occurs around age 20, earlier onset is associated
with poorer diagnosis
- the first episode of bipolar is usually depressive episodes, last longer than manic or
hypomanic episodes
- bipolar is often misclassified as major depressive disorder
Epidemiology and burden of illness
- lifetime prevalence of 2.4% and 12-month prevalence of 1.5%
- prevalence for bipolar I is similar for men and women, but bipolar II occurs more
frequently in women (MDD is also more prevalent in women)
- bipolar disorder first arises during formative years so developmental, educational
and occupational achievements are adversely affected
- around 6-7% of people with bipolar commit suicide, many sociodemographic and
clinical factors contribute to this
- people with bipolar have high rates of coexisting psychiatric conditions, including
anxiety, substance use, personality disorders, ADHD
- chronic medical conditions such as metabolic syndrome, obesity, and type 2 diabetes
are prevalent among bipolar patient
Genetic and neurobiological features
- heritability is 70-90%
- common genetic variants interact with environmental risk factors too
- a kindling hypothesis: explains gradual stress sensitization that leads to recurring
affective episodes sounds similar to diathesis-stress model
o the first episode of bipolar occurs after exposure to stressor
o subsequent episodes can occur without exposure
o mechanism underlying the hypothesis get stronger if it’s not treated or
person has lifestyle risks (substance use, smoking etc.)
o poorly characterized epigenetic mechanisms contribute as well
- neuroprogression (progressive changes in brain structure and cellular function) is
observed
o it may account for worsening of cognitive and functional impairments
o may contribute to other coexisting medical conditions
o long duration of illness, epigenetic mechanisms, mitochondrial functions,
neuroplasticity, inflammation, increase in oxidative and nitrosative stress may
be factors that promote neuroprogression
- abnormalities in the HPA axis plays a role in the progression of bipolar
- evidence indicates that as bipolar progresses response to mood-stabilizing
medications may decrease
Management
- most people go to their primary care clinician
- several factors influence initial treatment: patient’s preference, co-existing medical
and psychiatric conditions, previous responses to treatment etc.
- it should be determined whether the patient is at risk of suicide or aggression