Mood Disorders - Depressive Disorders Flashcards
depressive disorders types
- disruptive mood dysregulation disorder
- major depressive disorder (MDD)
- persistent depressive disorder - dysthymia (PDD)
- premenstrual dysphoric disorder
- substance/medication-induced depressive disorder
- depressive disorder due to another medical condition
bipolar and related disorders types
- bipolar 1disorder
- bipolar 2 disorder
-cyclothymic disorder - substance/medication-induced bipolar and related disorder
- bipolar and related disorder due to another medical condition
emotion continuum distinguishing
- duration
- impaired ability to function
- often occurs for no apparent reason
- involves extreme reactions not easily explained by what is happening in person’s life
- cluster of additional signs and symptoms
types of symptoms of depression
- behavioural
- cognitive
- emotional
- physiological
DSM5 criteria for MDD
A
- at least one major depressive episode
- never experienced a hypomanic or manic episode
- symptoms last for at least 2 weeks (for the majority of the time)
- change from baseline
- symptoms are not substance/medically-induced
DSM criteria for MDD episode
B
at least 1 of these:
1. depressed mood
2. anhedonia
at least 4 of these:
1. significant change in weight/appetite
2. insomnia or hypersomnia
3. psychomotor agitation/retardation
4. fatigue, loss of energy
5. feelings of worthlessness or inappropriate guilt
6. difficulty thinking and concentrating
7. recurrent thoughts of death, suicidal ideation (with or without plan), suicide attempt
DSM criteria for MDD with seasonal pattern
A
- at least 2 weeks
B
- same symptoms as the MDD episode
- associated with changes in daily as seasons change
- occurs more often in Northern latitudes
- previously termed seasonal affective disorder
recurrence of depressive episodes
- each major depressive episode increases risk of subsequent episode
- 1 episode = 50-60% will have another
- 2 episodes = 70% will have another
- 3 episodes = 90% will have another - with each subsequent episode, the length of time to recurrence is shortened
DSM5 criteria for PDD
A
- at least 2 years
B
-at least 2 of these:
1. poor appetite or overeating
2. insomnia or hypersomnia
3. low energy and fatigue
4. low self-esteem
5. poor concentration or difficulty making decisions
6. feelings of helplessness
at least 1 of these:
1. depressed mood
2. anhedonia
depressive reactions to grief
- important to distinguish from from normal grief-related reactions
grief
-often involves feelings of emptiness associated with the loss
- may last several years
- need to be carefully consider cultural, religious and age-appropriate norms
- frequency and intensity diminish over time
persistent complex bereavement disorder
condition undergoing study as a diagnostic category in DSM5
burden of depressive disorders - MDD
- lifetime prevalence 11.3% in Canada (2012)
- typical onset = late 20s
- 72% of individuals with MDD has comorbidity
1. anxiety disorder = 59%
2. substance use disorder = 24%
3. impulse control disorder = 30%
burden of depressive disorders - PDD
- lifetime prevalence 3-6% in Canada
- typical onset late childhood and adolescence
culture and depression prevalence
- individualistic cultures more likely to be diagnosed with depression than collectivist cultures
- why?
etiology of depressive disorders
- biological dimension
- psychological dimension
- social dimension
- sociocultural dimension
etiology - biological
- low levels of neurotransmitters
- heritability
- neuroendocrine systems(cortisol, stress, depression)
- anatomical and functional brain differences
- circadian rhythm disturbances
neurotransmitter dysfunction
- low levels of norepinephrine, dopamine, serotonin
- refer to functions of neurotransmitters in chapter 2 “perspectives”
- antidepressants medications
antidepressant medications in relation to neurotransmitter dysfunction
- increase the availability of neurotransmitters
- actual mechanism of how this works is not concrete
heritability
- genetic component with depression
- same types of disorders in families
- concordance rate of MDD (DZ=10%, MZ=40%)
- 35% variability in risk of developing MDD due to heritability (moderate genetic influence)
neuroendocrine dysregulation
- dyregulation and overactivity of HPA axis
- overpopulation of stress-related hormones (depressed people have higher levels of cortisol in their blood)
- influences mood, energy, appetite
- directionality is not concrete (no causal explanation)
brain changes with depression - have decreased brain activity and other brain changes
- decrease in neuroplasticity and neurogenesis in the hippocampus
- structural differences in hippocampus
- functional differences…
decrease of neuroplasticity and neurogenesis
reduced amount of neuro production
brain changes with depression - functional differences
- less activation in the prefrontal cortex
- more reactivity in amygdala
- increase for negative stimuli, decrease for positive stimuli
circadian rhythm disturbance
- internal biological rhythms maintained by melatonin
- sleep disturbances strongly linked with depression
- depression linked to disruptions (w/ and w/out seasonal patterns)
- irregularities in rapid eye movement
etiology: psychological
- behavioural
- cognitive
behavioural: Lewinson’s theory
depression occurs when people receive insufficient social reinforcements