Week 13

• 20% of people complaining of depression to their doctor actually have bipolar disorder
• About half of people with bipolar disorder see 3 professionals before being correctly diagnosed
• It takes an average of 10 years for people to enter treatment for bipolar disorder after symptoms begin
• The delay in treatment for bipolar disorder is caused in part by delays in diagnosis
• Most people with bipolar disorder have additional psychiatric conditions that can make overall diagnosis more challenging
• Manic and depressive episodes may occur in sequence, with or without a return to normal mood
• Patients may experience only one mood disorder episode, or the episodes can continue for months, or there may be periods of time without any mood disorder
• Bipolar disorder


  • Has developmental, genetic, neurobiological and physiological factors affecting its presentation
• It is likely that many genes are involved in genetically acquired mood disorders
• Medications that may lead to mania

  • Alcohol intoxication
  • Drug withdrawal
  • Antidepressants
  • Drugs that enhance dopamine activity
  • Non-prescription weight loss drugs
  • St johns wort
  • Others
• Medical conditions that may lead to mania

  • Endocrine or hormonal dysregulation
  • Infections
  • CNS disorders
  • Others
• Environmental factors that may lead to mania

  • Sleep deprivation
  • Bright light therapy
  • Deep-brain stimulation
• Bipolar type 1


  Patients likely experience a full manic episode and may or may not have a major depressive episode
• Bipolar type 2


  Patients likely experience hypomania and will have a major depressive episode
• Manic episode


  Times of exceptional energy, extreme happiness, poor or little sleep, restlessness, and risk-taking behaviour
• Someone with a manic episode is likely to be diagnosed with bipolar type 1 disorder
• Type 2 bipolar presentation


  Expected patient will have a major depressive episode lasting at least 2 weeks and at least one hypomanic episode, which likely does not require hospitalisation
• These patients may be initially misdiagnosed as having depression, as depressive symptoms may be the major symptom at the time the person seeks medical attention
• If the hypomania is not observed, recognised or reported initially, bipolar disorder diagnosis may be missed as the depressive symptoms become the focus
• Medications used to treat bipolar disorder

  • Lithium (mood stabiliser)
  • Atypical antipsychotics (e.g. aripiprazole, risperidone, clozapine)
  • Anticonvulsants (e.g. sodium valproate, carbamazepine)
  • Benzodiazepines (to assist with sleep)
• Antidepressants may provoke mania in people with bipolar disorder so antidepressant monotherapy is not recommended
• Stages of sleep


  1. NREM stage 1

  2. NREM stage 2

  3. NREM Stage 3

  4. REM sleep
• Lithium


  • Has been shown to have macro and micro effects which are generally neuroprotective
  • Works as a mood stabiliser and has very complex mechanisms of action
  • Thought to increase inhibitory neurotransmission via glutamate and dopamine
  • Has antioxidant and anti-apoptotic benefits
• Lithium's effects at the neuron level

  • Inhibits voltage-sensitive sodium channels as it mimics sodium, but it is not a substrates for sodium-potassium-ATPase, so lithium may accumulate in cells
  • Inhibits inositol monophosphate which blocks the phosphoinositide pathway, which is thought to modulate GPCR second messenger systems
• NREM stage 1


  Transition period between wakefulness and sleep, lasts about 5 to 10 minutes
• NREM stage 2


  Body temperature drops and heart rate slows. The body begins to produce sleep spindles. Lasts for approximately 20 minutes
• NREM Stage 3


  Muscles relax, blood pressure and breathing rate drop. Deepest sleep occurs
• REM sleep


  Brain becomes more active, body becomes relaxed and immobilized. Dreams occur and there are rapid eye movements
• Lithium's effects at the synaptic level


  • Inhibits excitatory neurotransmission
  • Promotes inhibitory neurotransmission
  • The combination of these two actions stabilises function between mania and depressive episodes
• Most adults experience about 90 minutes of REM sleep each night, which is roughly 25% total sleep time
• REM occurs mostly at the end of the night and it is when the brain is most active
• Lithium's effects at the dopaminergic synaptic level


  Interferes with the release of dopamine and reduces the involvement if inositol phosphate cycle, which reduces intracellular increases in calcium ions
• Increase in REM sleep

  Can improve symptoms of anxiety, depression, and cognitive brain function, as well as decreasing blood pressure
• Loss of REM sleep is not ideal
• Following sleep restriction or deprivation

  An individual might experience REM sleep rebound
• REM sleep rebound


  An increase above normal levels for a period of time
• NREM sleep


  Brain is undergoing metabolic rejuvenation, such as by restoring adenosine triphosphate (ATP) levels
• NREM stage 3


  Time of recovery from toxins in the brain and may only last for a total of forty minutes
• Causes of insomnia


  • Stress
  • Lifestyle
  • Physical pain
  • Neurological disorders
  • Other sleep disorders
  • Irregular sleep schedules
  • Mental health disorders
  • Medications
  • Age
  • Pregnancy
• Poor sleeping habits can be linked to our diet and metabolic health