Bipolar disorder is a mental disorder characterised by intense highs (mania) and intense lows (depression).
Whart is mania and what is depression
| Mood | Behaviour | Thoughts | |
|---|---|---|---|
| Mania | Expansive, euphoric, elevated, irritable | Increase in energy, decrease in sleep, extravagant recklassness | Racing, grandiose, unable to concentrate |
| Euthymia | Normal | Normal | Normal |
| Depression | Low, empty, depressed, hopelessness | decrease in appetite, decrease in energy, insomnia | Loss of interest/pleasure, suicidal thoughts, negative rumination. |
Diagnosis
General mood spectrum disorders
If you plot the magnitude of peaks found in ones disorder you get something like this:
This is a good idea of how unipolar depression and bipolar disorder relate. Note there is difference between BP-II, and BP-I
The criteria for diagnosis of BP is to have depressive episodes and at least 1 manic episode. If no manic episode it will be termed unipolar depression
This chart lists the diagnostic criteria for BP depression/MDD and mania
Epidemiology Precitipating factors and possible pathophysiology (not much given)
Epidemiology
The onset is around 18 for BP-II and 22y for BP-I. it is relatively equal between M and F sexes and when unmedicated it has a recurrence of 4 episodes a decade.
There is cycle acceleration as the interval between episodes decrease with age. A lifelong recurrence study done found there as a 2x higher recurrence compared to MDD
The lifetime prevelance is around 1-2%
Precipitating factors and Possible pathophysiology
BP is a highly genetic disorder with 75% chance of having it if your identical twin does. 60% chance if both your parents have it, and 20% with 1 BP parent or sibling.
The pathophysiology is not definitively understood. It is polygenic with each gene having a modest effect side. We also see white matter abnormalities in most major tracts in a study comparing BD vs controls. This is often used as a marker for tissue integrety
As per the diathesis stress model There is likely to be many environmental, psychological and medical conditions (and treatments) associated with development.
Resulting adverse health associations
Having BP means severe reductions in lifespan and “quality”. These patients die 8-9yrs earlier compared to non-bp population, have an 8-10x higher suicide risk, and have high rates of incarceration unemployment and poverty
Treatments
There are nondrug interventions and drug interventions.
Nondrug interventions
This can be a number of things, like psychological and social management, as well as possible hospitalisation when needed.
Education is important, about the disorder and treatments, as well as the important of stable lifestyle routines and when to tell when there could be a coming episode.
Case management is important, with careful review of symptoms and side effects with each clinical visit, as well as life charting of previous episodes, like a daily mood diary
Social/psychological support/Therapy is also useful, with specific psychological therapies and psychoeducation being important.
IN acute mania, hospitalization may be necessary. Possibly requires low stimulus environment, boundary setting, supervised medication, and prevention of suicide possibly involving the use of the mental health act may be invoked
And drug therapy too:
Drug interventions
The drugs used are often mood stabilisers (LI or valproate) and antipsychotics (risperidone, olanzapine) and even possibly benzos.
These exist on a spectrum with some being more antidepressant, and some being more antimanic. 
All drug options are better than placebo in acute mania and antipsychotics with mood stabilisers are most effective.
Management of Bipolar depression
Mood stabilisers tend to have good antidepressant effects, with 80% of bp patients showing a good or partial response to lithium
Onset of activity may not be seen for 6-8 weeks, and other mood stabilisers arent as studied as lithium.
Antidepressants should be used cautiously in BP depression, Use along with a mood stabiliser and it is difficult to demonstrate antidepressant beenfit in RCTs. There is a risk of the antidepressants leading to mania or inducing rapid cycling. Ketamine may be useful
Bipolar mantainance therapy
Prophylaxis is needed if there are 2 or more episodes in 5 yrs. Lithium is first choice and despite efficacy recurrence can occur. its important to maintain adequate blood levels, and check body characteristic which could effect this. Poor tolerability may reduce compliance. Other mood stabilisers (Valproate/Carbamazepine/Lamotrigine) can work but there is no obvious advantages ove lithium. Antipsychotic monotherapy is quetiapine.