Bipolar Disorder Flashcards
What is mood?
a pervasive and sustained emotion or feeling tone that influences a person’s behavior and colors his/her perception of the world
-can be labile, fluctuating, or alternating rapidly between extremes
Differentiate cyclothymia and dysthymia.
cyclothymia: mood swings between short periods of mild depression and hypomania
dysthymia: persistent depressive disorder
What is bipolar disorder?
a chronic mood disorder subcategorized into bipolar I disorder and bipolar II disorder
Differentiate BDI and BDII.
BDI: a distinct period of at least ONE week of a full manic episode (abnormally & persistently elevated mood and increased energy)
BDII: a current and/or past hypomanic episode AND a current and/or past major depressive episode
Describe the epidemiology of bipolar disorder.
men=women
-men have more manic episodes, women more depressive or mixed
lifelong illness with variable course
True or false: there is a cure for bipolar disorder
false
however, recovery/maintenance is possible
What is the etiology of bipolar disorder?
multifactorial and many interrelated risk factors at play
-genetics
-neurobiological
-developmental
-psychologic
What is the pathophysiology of bipolar disorder?
the exact cause of bipolar disorder is unknown
-several theories involving neurotransmitters and signal transduction have been proposed
What are the risk factors for bipolar disorder?
drug or alcohol abuse
1st degree relative
period of high stress
major life changes
medical conditions (hyperthyroid, CVD, endocrine, CNS, hormonal)
What are some secondary causes of mania that are medication/drug related?
antidepressants
-SNRI > TCA > SSRI > mirtazapine
-may need to abruptly d/c if severe mania and push through FINISH sx
DA-augmenting agents
-stimulants (caffeine, decongestants, amphet, cocaine)
-sympathomimetics
-DA agonists/releasers/reuptake inhibitors
NE-augmenting agents
alcohol and cannabis
thyroid preps
steroids (anabolic, corticosteroids)
What is the average age of onset for bipolar disorder?
20-25
-2/3 people with BD have sx before age of 18
What is the risk with those who develop bipolar disorder before the age of 19?
longer delay to treatment
greater depressive symptom severity
higher levels of anxiety/substance use and comorbidity
Describe the prognosis for bipolar disorder.
with tx, illness usually includes periods of remission with risk of full or sub-syndromal relapses
Kindling Theory
-abnormalities lead to more abnormalities
-syndromal episodes increase vulnerability to more episodes
neurodegeneration (because of kindling)
-delayed functional recovery, increasing impairment, neurocognitive deficits
profound morbidity and mortality
-impairment, hospitalization, increased mortality
What is the best predictor of functioning for someone with bipolar disorder?
medication adherence
-50% of patients d/c their meds due to AE’s
What are some medical conditions that can worsen and/or make bipolar disorder difficult to treat?
anxiety (50-60%)
substance use disorder (60%)
-alcohol=most common
ADHD
PTSD
DM, dyslipidemia, CVD, obesity
What is one of the leading causes of death in patients with bipolar disorder?
suicide
-20x higher risk than general population
-men at increased risk
-worldwide 43% of BD pts report suicidal ideation
What should occur during any patient interaction regarding bipolar disorder?
suicide risk assessment
What is the diagnostic criteria for mania?
abnormally and persistently elevated mood and energy with at least 3 of the following changes from usual behavior: DIGFAST
sx present nearly every day for at least one week
leads to significant functional impairment OR requires hospitalization OR includes psychotic features
episode not due to physiologic effects of a substance or medical condition
What is the mnemonic to help remember the symptoms of mania?
DIGFAST
distractibility
irritability
grandiosity
flight of thoughts
activity/energy increased
sleep decreased
talkability
What is the diagnostic criteria for a hypomanic episode?
same sx criteria as manic episode but only lasting up to 4 days
unequivocal change in functioning or mood that is uncharacteristic of the individual and/or observable by others
impairment in social/occupational functioning is not severe, no hospitalization, no psychosis
episode not attributable to physiological effects of a substance or medical condition
shorter time period, less severe
Differentiate the diagnostic criteria for BDI and BDII.
duration of manic sx:
-BDI: > 7 days
-BDII: < 4 days
functional impairment:
-BDI: yes
-BDII: no
psychotic features:
-BDI: yes
-BDII: no
requires hospitalization:
-BDI: yes
-BDII: no
history of depression:
-BDI: no
-BDII: yes
What is the diagnostic criteria for a major depressive episode?
5+ sx present nearly every day in the same 2 week period that result in change in functioning
-one or both of: depressed mood, anhedonia
SIG E CAPS
What is an example of a patient rated scale for BDI/II?
mood disorder questionnaire (MDQ)
-used to screen for possible BD
-most specific for identifying BDI
-positive if “yes” to 7/13 items in Q2, “yes” to Q2, and “moderate or severe problem” to Q3
What are the challenges in bipolar disorder diagnosis and treatment?
delay to diagnosis
-avg delay 8-12 yrs
-often pts do not recally hypomanic sx
-more likely to seek help for depression vs mania
misdiagnosis
-most common: depression
limited clinical trials
What are the goals of therapy for bipolar disorder?
- eliminate mood episode with complete remission of symptoms, ongoing (acute treatment)
- prevent recurrences or relapses of mood episodes, ongoing (maintenance treatment)
- improve quality of life and optimize psychosocial functioning, ongoing
- minimize harm to self and others (including prevent suicide), ongoing
- maximize adherence and minimize adverse effects of pharmacotherapy, ongoing
- identify and minimize risk factors for mood episode, ongoing
- provide care for comorbid psychiatric, substance use, or medical conditions, ongoing
- provide education to patient and family members, ongoing
Describe the timeline for improvement once medication is initiated for mania and depression.
mania:
-response 1-2 weeks
-full clinical benefit 3-4 weeks
depression:
-response 2-4 weeks
-full clinical benefit 6-12 weeks
List some of the non-pharm strategies for bipolar disorder.
exercise, healthy diet, adequate sleep
decrease substance use/alcohol/nicotine/caffeine
psychoeducation, psychotherapy, counselling
ECT
bright light therapy (more for depression)
relapse prevention plan
What are the most commonly used mood stabilizers?
lithium
valproic acid/divalproex
lamotrigine
Which mood stabilizers see limited use due to their adverse reactions and drug interactions?
carbamazepine
oxcarbazepine
Which mood stabilizers are rarely used due to lack of efficacy and poor tolerability?
topiramate
gabapentin
What are the indications for lithium?
bipolar disorder (acute mania tx, maintenance tx)
schizoaffective disorder
unipolar depression (antidepressant augmentation)
What is the MOA of lithium?
exact MOA not fully understood
has multiple effects on cellular function
Describe some important points about the absorption of lithium.
completely dissociates to lithium cation
-almost completely absorbed from small intestine
-small amount actively exchanged for sodium
F of liquid and regular release > extended release
Describe some important points about the volume of distribution of lithium.
initially distributes in extracellular space
then accumulates in various organs
distributes evenly in total body water space
What is the half-life of lithium?
normal renal function: 12-27 hours
elderly: 30-36 hours
Describe some important points about the elimination of lithium.
95% renal, 4% perspiration
not metabolized, primarily excreted renally as free cation
not protein bound –> freely filtered by glomerulus like Na and K = 80% reabsorbed in proximal tubule
What are some scenarios that can lead to decreased clearance of lithium?
hyponatremia
dehydration
renal failure/dysfunction
decreased renal blood flow
What kind of PK does lithium show?
linear, dose-proportional PK
When should a lithium sample level be taken?
12 hour post dose level
-in AM after evening dose (allows complete absorption and distribution)
STAT if toxicity or non-adherence is suspected
How frequent should lithium sample levels be taken?
5-7 days after starting therapy or changing dose
then once weekly until stabilized dose x 2 weeks, then monthly for up to 3 months, then at least every 6 months
How is lithium typically initiated during acute mania?
higher initial doses
-increases likelihood of GI side effects
subsequent doses guided by plasma level and clinical response
How can we help minimize the GI side effects experienced when initiating lithium?
take with food and/or divide dose BID
How is lithium typically given once the patient is stabilized?
once daily
-usually given at night to improve compliance
What are some benefits that some trials have shown with the once daily evening dosing of lithium?
decrease in urine volume and decreased renal toxicity
What could a potential solution be for a patient experiencing peak related side effects to lithium?
change to extended release formulation
What should be done when toxic levels of lithium are suspected?
hold dose
repeat plasma level the next day
restart therapy once within target range
What are some factors that might decrease lithium levels?
caffeine
pregnancy
sodium supplement
burns
hemo/peritoneal dialysis
theophylline
acetazolamide
sodium bicarb
What are some factors that might increase lithium levels?
ACEI/ARBs
NSAIDs
thiazide diuretics
dehydration
strenuous exercise
SSRI/SNRI
chronic lithium use
renal impairment
increased age
sodium loss
cirrhosis
What are the drug interactions with lithium?
diuretics
-may have mixed effects
NSAIDs
-decreased lithium clearance=increased lithium levels
ACEI/ARBs
antipsychotics
-additive risk of neurotoxicity
antidepressants
-theoretical risk of serotonin syndrome (monitor)
What are the common side effects of lithium?
increased thirst and urinary frequency
-dose related
fine tremors in hands/arm
-dose related
-usually symmetrical
headache, sedation, weakness
-dose related
GI upset
-dose related
-usually one of first signs of toxicity
skin changes
-acne, psoriasis
-dose related
alopecia
weight gain
-avg 4-6kg in first 2y
What are the serious side effects of lithium?
hypothyroidism
renal injury
-interstitial nephritis, renal failure, ESRD
blood dyscrasias
bradycardia or conduction abnormalities
nephrogenic diabetes insipidus
In addition to typical counselling pieces, what else should be discussed with lithium?
may take several weeks to see benefit
maintain adequate hydration and consistent salt/caffeine intake
avoid NSAIDs; talk to pharmacist before starting new med
consider contraception if child-bearing age
will require regular blood level monitoring
regularly check elytes, renal, thyroid, serum level
if tolerated + stabilized, consider OD dosing hs (less AE and less renal risk)
How can the common side effects of lithium be managed?
thirst: drink water, hard candies (should subside)
sedation: take hs, dont drive
nausea: take with food; consider ER if doesnt subside
acne: talk to pharmacist or MD for tx
tremor: talk to MD if it doesnt subside
What is the difference between valproic acid and divalproex?
divalproex is the prodrug of valproic acid
What are the indications of valproic acid?
seizures: generalized tonic-clonic, partial onset, absence
-broad spectrum antiepileptic activity
bipolar disorder: acute mania tx, maintenance tx
What is the MOA of valproic acid?
exact MOA is unknown
possible mechanisms:
1. inhibition of voltage-gated Na+ channels
2. increasing action of GABA
3. modulates signal transduction cascades and gene expression
4. may effect neuronal excitation mediated by NMDA subtype of glutamate receptors
5. also effects 5HT, DA, aspartate, and T-type Ca2+ channels
Is valproic acid well absorbed or poorly absorbed?
well absorbed from all oral dosage forms but rate of absorption varies
-F: 0.9-1.0
Describe the protein binding of valproic acid.
85-90% bound to serum albumin
saturable protein binding occurs within therapeutic range
-at 500umol/L VA is 90% bound to albumin
- >500umol/L binding saturates and there is increased free
Describe the elimination of valproic acid.
> 95% hepatic metabolism
-majority by glucuronidation and oxidation
-minority by CYP
-4-ene-VA metabolite can cause liver toxicity
True or false: valproic acid is a low extraction drug
true
Cl is independent of hepatic blood flow but directly dependent on free fraction
What is the half-life of valproic acid?
12-18 hours
-closer to 12 hours if taking enzyme inducing drugs
What is the therapeutic range of valproic acid?
total 350-700umol/L (50-150mcg/ml)
TR is a guideline only and must be individualized