8 - Depression and Schizophrenia

Question 1

What is the lifetime prevalence of major depression? What gender is it more common in? What is the mean age?

Answer 1

15% prevalence

2x more common for women

More common is there’s a family history.

Mean age is 40 but it can occur at any age.

Question 2

What can increase the risk of major depression?

Answer 2

Losing a close relationship.

Question 3

How long doe major depression last if untreated? What about when treated?

Answer 3

Untreated: 6-12 mo
Treated: can often resolve in 2 mo

Question 4

What is the risk of recurrence of MDD?

Answer 4

40% recur within 2 yrs after resolution, up to 85% recur at some point.

Question 5

What are symptoms of major depressive disorder? What makes someone “qualified” for the diagnosis of MDD?

Answer 5

5 of more symptoms for 2 wk duration:

Change in sleep and appetite 
Decreased energy
Suicidal ideation 
Anhedonia 
Decreased concentration and memory 
Depressed mood 
Feeling worthless/helpless/ excessive guilt 
Psychosis can occur

Question 6

What is the suicide risk for someone with MDD in their life? What about during an episode?

Answer 6

10-15% lifetime risk

During single episode of MDD, 66% consider suicide.

Question 7

What would a differential for MDD look like (ie what are other pathologies that could look like MDD)?

Answer 7

• Bipolar depression
• Dysthymia (low grade chronic depression)
• Grief
• Adjustment Disorder (symptoms less than 2wks)
• Hypothyroidism
• Substance induced (depressants or withdrawl from stimulants)
• Chronic heart failure/hypoxia
• Parkinsons
• HIV

Question 8

What is the etiology of MDD?

Answer 8

Genetic: first degree relatives re 2-4x more likely to develop major depression

Functional polymorphism region of 5-hydroxytryptamine transporter - increase risk of depression in response to stressful events.

Question 9

What nts are involved in MDD?

Answer 9

Catecholamines and serotonin

Question 10

How is serotonin made?

Answer 10

1. Trp gets OH removed by trp hydroxylase to become 5-hydroxytryptophan
2. Amino acid decarboxylase removes COOH to become serotonin (5HT)

Question 11

What are things that can metabolize serotonin? Why are these important?

Answer 11

Monoamine axidases
Aldehyde dehydrogenases
5-Hydroxyindole acetic acid

Blocking these will cause an increase in serotonin.

Question 12

What are some treatments for MDD?

Answer 12

SSRIs, SNRIs (norepi and serotonin) , Tricyclics (increase levels of norepi and epi) , MAOI’s (serotonin and catecholamines), psychotherapy, ECT, rTMS (magnetic pulses to increase flow and impact nts)

Question 13

What is the prevalence of schizophrenia? What is the age of onset?

Answer 13

Lifetime prevalence of 1-2%, equal prevalence in males and females .

Male age of onset is late teens. Female is early twenties.

Question 14

What are the positive symptoms associated with schizophrenia?

Answer 14

Delusions (falsely based beliefs), paranoia, hallucinations (auditory or visual), and disorganized through process.

Question 15

What are the negative symptoms associated with schizophrenia?

Answer 15

Blunted affect
Alogia - lack of spontaneity of speech 
Lack of motivation
Anhedonia 
Poor hygiene

Question 16

What is the suicide risk for people with schizophrenia? Why is life expectancy shortened when people have schizophrenia?

Answer 16

10% lifetime risk

Shortened life expectancy due to social isolation and because their psychosis can cause a them to not get the healthcare they need. They also have a higher risk for nicotine addiction.

Question 17

What is the DSM’s criteria for schizophrenia?

Answer 17

2 or more of the following symptoms persisting for at least 1 month with continuing signs of disturbances for 6 mos:

• delusions
• hallucinations
• disorganized speech
• disorganized behavior or catatonia, negative symptoms.

Question 18

Describe the course of schizophrenia?

Answer 18

Lifeling illness with psychotic exacerbations.

Negative symptoms tend to be chronic and longstanding.

Question 19

What are schizoidal PD and schizotypal PD?

Answer 19

Schizoidal: people tend to have negative symptoms

Schizotypal: tend to have lover grade positive symptoms

Question 20

What is the genetics etiology of schizophrenia?

Answer 20

108 loci implicated with increased risk: major histocompatibility complex on chrom 6, TF factor 4, neurogranin, and zinc factor 4.

micro RNAs implicated

These only account for a small fraction of the heritability.

Question 21

What are some environmental factors that play a role in the development of schizophrenia?

Answer 21

Chronic psychostimulant use. 
Migrant status 
Advanced paternal age 
Having a cat 
Prenatal nutrition deprivation
Cannabus use 
Urban residence 
Winter or spring birth

Question 22

What is the popular working model of schizophrenia?

Answer 22

That it’s a neurodevelopmental disease that emerges when environmental stress is imposed on a genetically susceptible background.

Question 23

What can alter epigenetic markers associated with schizophrenia?

Answer 23

Environmental factors.

Question 24

What structural abnormalities in the brain are associated with schizophrenia?

Answer 24

Decrease in brain volume size, increased size of ventricles.

Question 25

What is the dopamine theory for schizophrenia?

Answer 25

Hyperfunction of the mesolimbic system causes + symptoms and hypofunction in the mesocortical region causes - symptoms.

Question 26

What is the GABA theory for schizophrenia?

Answer 26

Hypofunction of the presynaptic GABAnergic neurons, but genes related to GABA function do not figure into schizophrenia so it could be a downstream effect.

Question 27

What is the glutamate theory about schizophrenia? What supports this theory?

Answer 27

There is a hypofunction of NMDA receptors found.

PCP is a dissociative drug that blocks NMDA and causes psychotic symptoms.

Question 28

What are the two current treatment options for those with schizophrenia?

Answer 28

1. Typical antipsychotics - D2 blockers (helps + symptom but worsens - symptoms)
2. Atypical antipsychotics - D2/4 blockers with 5HT2 blockers

Question 29

How do atypical antipsychotics work? What is the down side to these medications?

Answer 29

They decrease dopamine in the mesolimbic region and stimulate dopamine in the mesocortical area. Sometimes allows decreased - symptoms.

More likely to cause weight gain and adult onset diabetes with long-term use.