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Flashcards in Lec 72 Mood Disorders Deck (28)
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1

What are DSM diagnostic criteria for major depressive disorder?

must have depressed mood OR anhedonia
must cause significant distress or impairment and there has never been manic episode
5 or more of the following for > 2 wks
- depressed mood
- anhedonia = lack of interest
- sleep disturbance = in/hypersomnia
- change in appetite
- low energy
- psychomotor agitation or retardation
- impaired concentration
- guilty feeling/self blame
- suicidal/thoughts of death

2

What is prevalence of major depressive disorder [MDD]?

~15% across different populations
more in women [1 in 4] than men [1 in 8]
pre-pubertal = equal men to women

3

What is course of MDD?

- may be triggered by event or may have no trigger
- untreated episode lasts 6-13 mo
- treated lasts 3 mo
- chronic with relapses

4

What percent of untreated MDD attempt suicide?

30%

5

What are the 4 theories of depression etiology?

- psychodynamic
- cognitive
- neurobiological
- genetics

6

What is the psychodynamic theory of MDD?

by freud
- depression linked to real or imagined loss of a loved object and resulting damaged self esteem and unresolved conflict
- can be seen as anger turned inward

goal of treatment = promote symptom relief and personality change through understanding of unconscious conlifcts

7

What is the cognitive theory of depression?

by Aaron beck
- depression from specific cognitive distortions
- cognitive triad
---- negative views of self
---- negative views of environment
---- negative views of future

8

What are the neurobiological theories of MDD?

many theories from molecular and cellular level to whole brain imaging/neuro circuitry level

- MOA [DA/5HT/NE] deficiency
- glutamate dysregulation [excess glu]
- neuroendocrine [HPA] dysregulation
- structural and functional brain changes
- neuropathological changes
- impairments in neuroplasticity

9

What is the MOA deficiency hypothesis of depression?

depression is result of deficiecny of MOAs [5HT, DA, NE]

proof: early antidepressants blocked reuptake or degradation 5HT/NE
reality: its a more complicated picture

10

What is the AA NT system dysregulation theory of depression?

- chronic stress --> excess glutamate
- hyperactivation of NMDA glu receptors --> atrophy and death of neurons/glial cells

treat by ketamine = NMDA antagonist

11

What is the neuroendocrine dysregulation theory of depression?

- increased cortisol, CRF
- lack of normal cortisol suppression when given dexamethasone suppression test [DST]
- less negative feedback sensitivity
- less glucocorticoid receptor sensitivity
- hippocampus damaged

problem with this theory = no evidence of HPA dysfunction in many pts

hypercholesterolemia may be associated with very severe depression only

12

What are structural and functional brain changes thought to cause depression?

reduced volume in all the following areas plus:
reduced activity in:
- dlPFC = decision making, judgement
- ACC = motivation, reward, empathy

increased activity in:
- OFC = socially appropriate behavior
- amygdala = memory of emotional events

dlPFC + hippo = cognitive aspects of depression

lack of cortical regulation of limbic system

13

What neuropathological changes associated with depression?

- reduction glial cell density + number [maybe due to glu toxicity from stress]

14

What impairments in neuroplasticity associated with depression?

- decrease neurotropic factors
- subsequent failure of neuronal plasticity

decreased BDNF in depressive; inverse correlation level of BDNF and sensitivity to stress in healthy people

15

What is role of brain derived neurotrophic factor [BDNF]?

imp for axonal growth, neuronal survival, allowing changes in synapses between neurons throughout life

levels of BDNF affected by stress and cortical

16

What is the final common path for all effective therapies?

enhancement in neural plasticity and cellular resilience

17

What are genetics of depression?

- heritability
- no single depression gene = multiple genes combined with environmental causes

18

What is the gene/environment interaction of 5HT transporter gene in depression?

carriers of short allele of 5HT transporter gene can make vulnerable to depression under stress

19

What is treatment for MDD?

medications like SSRIs, tricyclic antidepressants, MOA inhibitors
psychotherapy
ECT therapy
vagal nerve stimulation

20

What are diagnostic criteria for manic episode?

- at least 1 wk abnormally and persistently elevated mood PLUS
3-4 of:
- inflated self esteem/grandiosity
- decreased need for sleep
- more talkative
- flighty ideas
- distractibility
- psychomotr agitation
- psychotic/impaired functioning
- excessive involvement in pleasurable activities with high potential for painful consequence

21

What are diagnostic criteria bipolar 1 disorder?

- at least 1 manic episode

typically have recurrent episodes both mania/hypomania and depression but not required for diagnosis

22

What is the prevalence of bipolar 1 disorder?

0.5-1%
equal in men/women
mean age onset = 18-21 yrs

23

What is course of bipolar disorder?

most have manias + depressions --> 10-20% ONLY manias
long term --> 15% well; 45% well but multiple relapses

more than 90% of individuals who have a single manic episode go on the have recurrent episodes

24

What is the neurobiology of bipolar disorder?

- dysregulation in limbic and prefrontal cortical circuitry
- HPA axis dysregulation
- decreased neuronal size and density

25

What are genetics of bipolar disorder?

8-10x increased risk in 1st degree relatives of bipolar; also 2-10x increase of MDD in 1st degree relatives of bipolar

65% heritability [compared to MDD 30%]
no one gene identified

26

What is epidemiology fo suicide?

10th leading cause of death in americans
highest in men older than 75
3rd leading cause of death age 15-24

almost all who kil themselves have diagnosable mental disorder; approx 2/3 of those who complete have seen a physician within a month of death

27

What are risk factors of suicide?

- family history
- demographics [older white male]
- previous suicide attempt
- psych disorders [esp MDD]
- substance abuse
- hopelessness
- impulsive or aggressive tendencies
- isolation [divorced, few friends]
- barriers to accessing treatment

28

What are protective factors for suicide?

- good clinical care
- easy access to clinical interventions
- connectedness
- skills in problem solving
- children