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Affective and Anxiety Disorders
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Affective and Anxiety Disorders. What are affective disorders? Disorders of mood found throughout history unipolar or major depression bipolar or manic.

Jan 11, 2016

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  • Affective and Anxiety Disorders

  • What are affective disorders?Disorders of moodfound throughout history

    unipolar or major depression

    bipolar or manic depression

  • DepressionDepressionover 10% with ~ 5% (11,000,000) suffering from a depressive episode in any given yearuntreated - 25 - 30% will attempt or commit suicide2X greater prevalence in women than menestimated only ~ 50% receive specific treatment

  • Characteristics of Depression

  • Biological Factors Influencing liklihood of depressionGeneticsconcordance rates:fraternal twins - 20% concordancemonozygotic or identical twins - 50% concordance

  • Neurochemical Theorymonoamine theory:

    supportive data

    1. Reserpine makes synaptic vesicles leak NT

    2. Drugs used to treat depression increase activity of NE and/or 5HT neurons

  • How do we treat depression?Pharmacologicallydrugs have been available for ~ 40+ years

    two categories of drugs emerged about the same time; tricyclic antidepressants and MAO inhibitors

    more recently SSRIs have taken over the market

  • So how do these antidepressants work?

  • Tricyclic antidepressantsBlocks reuptake of NE and 5HTvery widely usedfairly significant side effectsmainly because they block ACh receptorsblurred vision, dry mouth, urinary retention, irregular heart rate, constipation, sexual dysfunction, effects on other NTsedation, weight gain

  • SSRIsFluoxetine (Prozac) - first introduced in US in 1988SSRIs have a more favorable side effect profile than earlier antidepressantsrelatively safe (esp in OD situations)some controversy... increased risk of suicide especially in kids

  • (Celexa)

  • How do SSRIs work?Block reuptake of 5HTselective serotonin reuptake inhibitor

  • MAO inhibitorsdefinitely not first line for treatment

    MAO- enzyme that breaks down excess DA, NE, 5HT so MAO inhibitors result in increased DA, NE and 5HT

  • Limitations of MAO inhibitors

    can cause significant interaction when people consume certain foods

    consequence potentially hypertensive crisis could be stroke

    Alters the metabolism of an amino acid that fools sympathetic nervous system into getting overstimulated

  • Limitations of MAO inhibitors

    Alters the metabolism of amino acid tyraminefoods high in tyramine include: aged cheeses, wine, smoked fish, yeast products

  • Limitations of MAO inhibitors

    consumption of these can result in a hypertensive crisis:severe headaches, heart palpitations. Flushing, nausea, vomiting, strokevery long life (drugs stay in body for at least a couple of weeks)There are now some MAO inhibitors that clear the body more quickly but still these are never the first drugs considered

  • Current problems that still exist with pharmacotherapy of depressionSome patients do not respond well to first treatment

    most take 3 - 4 weeks to exert significant therapeutic effects

  • How is this explained in terms of NT activity?

    NT activity is changed very quickly with psychotropics

    Most believe it is more related to change in number or sensitivity of postsynaptic receptors (down or up regulation)

  • Current problems that still exist with pharmacotherapy of depressionAmount of time needed to see therapeutic effect (already discussed)

    Some patients do not respond well to first treatment

  • Three alternatives to drug treatment1. ECT - electroconvulsive therapymay cause the most rapid change in receptor density2. Sleep deprivationmany sleep abnormalities associated with endogenous depressionreduced SWS, increased stage 1, increased REM

  • 3. Phototherapy - Seasonal Affective Disorder92% survey responders noticed seasonal change in mood27% claim it causes them problems4% diagnosed with SAD

  • Bipolar1% incidence (lower than depression)symptoms usually emerge during adolescence or early adulthoodno sex differences in incidencewithout effective treatment - ~ 20% result in suicide

  • Bipolar disorderTreatmentsoldest - lithiumodd history-lithium metal isolated in early 1800s1940s - replaced sodium chloride with lithium chloride for hypertensive patientsreintroduced to treat bipolar in 1970

  • Bipolar disorderTreatmentsoldest - lithiumodd history-lithium metal isolated in early 1800s1940s - replaced sodium chloride with lithium chloride for hypertensive patientsreintroduced to treat bipolar in 1970limitations of lithiumeffective dose and toxic dose are TOO closeregular blood monitoring

  • Newer treatmentsnewer anticonvulsants Anticonvulsants MUCH SAFER THAN LITHIUM!!!carbamazepine (Tegretol) or valproic acid (Divalproex)

    Potential issue recent study showed that the anticonvulsants may improve symptoms but are not as effective as lithium at reducing suicides and suicide attempts