Clinical Descriptions and Epidemiology of Mood Disorders

  • 2 broad types of mood disorders according to DSM-5: 1) Depressive, 2) Manic (bipolar)

Depressive Disorders

  • Cardinal symptoms: profound sadness, and/or inability to experience pleasure
  • Physical symptoms: fatigue, low energy, physical aches/pains *convince individual they are suffering from serious medical conditions o Difficulty falling asleep, bland taste, change in appetite, disappearance in sexual interest, limbs feel heavy
    • Psychomotor retardation = thoughts and movements slow
    • Psychomotor agitation = inability to sit still (pace, fidget, wring their hands)  Major Depressive Disorder (MDD):
    • MDD – diagnosis requires 5 depressive symptoms to be present for at least 2 weeks, must include either depressed mood or loss of interest and pleasure
    • Additional symptoms must also be present: changes in sleep, appetite, concentration/decision making, feelings of worthlessness, suicidality, psychomotor retardation/agitation
    • Episodic disorder = symptoms tend to be present for a period of time and then clear o Untreated episode may stretch for 5 months+
    • Episodes tend to reoccur, 2/3 who experience 1 episode, will experience at least 1 more o Average: 4 episodes (with each new episode, chance of reoccurrence goes up 16%)  DSM-5 Criteria:
      • 1) Sad mood or loss of pleasure in usual activities
      • 2) At least 5 symptoms (counting sad mood and loss of pleasure)
    • Sleeping too much/too little
    • Psychomotor retardation/agitation
    • Weight loss/change in appetite
    • Loss of energy
    • Feelings of worthlessness/excessive guilt
    • Difficulty concentrating, thinking or making decisions
    • Recurrent thoughts of death/suicide
    • 3) Symptoms are present nearly every day, most of the day for at least 2 weeks
    • 4) Symptoms are distinct & more severe than a normative response to significant loss o Sub-clinical depression = sadness plus 3 other symptoms for 10 days
    • Significant impairments in functioning even though full diagnostic criteria are not met  Persistent Depressive Disorder (PDD):
    • PDD –chronically depressed, more than half of the time for at least 2 years, have at least 2 of the other symptoms of depression
    • Central feature: chronicity of symptoms o Similar to a DSM-IV-TR diagnosis of dysthymia
      • DSM-5 Criteria:

1) Depressed mood for most of the day more than half of the time for 2 years (1 for children/adolescents)

2) At least 2 of the following during that time:

 Poor appetite/overeating, Sleeping too much/too little, Low energy, Poor SE, Trouble concentrating/making decisions, Feelings of hopelessness

3) The symptoms do not clear for more than 2 months at a time

4) Bipolar disorders are not present  Other DSM-5 Depressive Disorders:

  • Disruptive mood dysregulation disorder = newly defined depressive disorder, a diagnosis specific to children and adolescents
  • Premenstrual dysphoric disorder = moved from DSM-IV appendix to main diagnostic section  Epidemiology and Consequences of Depressive Disorders:
  • MDD – one of the most common psyc disorders (16.2% US will meet criteria at some point)
  • Chronic forms are rarer (PDD), about 2.5% US meet criteria for dysthymia (DSM-IV-TR) o Twice as common among women as among men o MDD is 3x as common among impoverished o Prevalence varies considerably across cultures
  • Rates of winter depression (SAD) higher farther from the equator, days are shorter o Countries with more fish consumption have lower MDD/bipolar rates o Child symptoms: stomach/headache, Adult: distracted, forgetfulness o Adolescent males: irritability, anger
  • Korea – less likely to describe sad mood/suicidal thoughts o Latino culture – complaints of nerves/headaches
  • Asian culture – reports of weakness, fatigue, and poor concentration
  • Smaller distance from equator and higher fish consumption associated w/lower rates o Age of onset has become lower for each recent generation of people in US o Age of onset: late teens, early 20s
  • 60% who meet criteria for MDD will also meet criteria for anxiety o Other comorbidities: substance use, sexual dysfunction, personality disorders o MDD is a leading cause of disability in the world o 2/3 will also meet criteria for anxiety disorder

Bipolar Disorders

  • 3 forms (DSM-5): bipolar-I, bipolar-II, cyclothymic disorder
  • Manic symptoms are the defining feature (most also experience depression)
  • Episode of depression is not required for bipolar-I, it is required for bipolar-II
  • Mania = a state of intense elation, irritability, or activation accompanied by other symptoms
  • Flight of ideas = difficult to interrupt, shifting rapidly from topic to topic
  • Stop sleeping, extremely self-confident, incredibly energetic
  • Risky sexual activities, overspending, reckless driving
  • Hypomania = less extreme than mania (under mania), does not involve significant impairment, involves a change in functioning that does not cause serious problems  Bipolar I Disorder:
    • Formerly known as manic-depressive disorder
    • Diagnosis: includes a single episode of mania during the course of a person’s life o Bipolar episodes tend to recur
    • More than 50% experience 4+ episodes during their life time o Toughest to diagnose
  • Bipolar II Disorder:
    • Midler form
    • Must experience at least one major depressive episode and at least one episode of hypomania (and no lifetime episode of mania)  Cyclothymic Disorder:
    • Aka cyclothymia – a second chronic mood disorder (like PDD)
    • Symptoms must be present of at least 2 years among adults (1 year in children) o Frequent, but mild symptoms of depression, alternating with mild symptoms of mania o Symptoms don’t clear for more than 2 months at a time  Epidemiology and Consequences of Bipolar Disorders:
    • 1% prevalence in USA, 0.6% worldwide (Bipolar I), 0.4% Bipolar II, 4% cyclothymia o Bipolar I is much rarer than MDD o More than 50% report onset prior to age 25
    • Being seen with increased frequency among adolescents and children o Occurs equally often in women and men o Women diagnosed experience more depression than men o 2/3 diagnosed meet diagnosis for comorbid anxiety o Many report a history of substance abuse o Bipolar I is one of the most severe psyc disorders o Suicide rates high for bipolar I and II
    • People hospitalized for bipolar I 2x as likely to die from medical illnesses in a given year compared to people without mood disorders DSM-5 Criteria for Manic and Hypomanic Episodes:  Distinctly elevated or irritable mood
  • Abnormally increased activity or energy
  • At least 3 of the following are noticeably changed from baseline (4 if irritable mood):
    • Increase in goal-directed activity or psychomotor agitation o Unusual talkativeness – rapid speech
    • Flight of ideas or subjective impression that thoughts are racing o Decreased need for sleep
    • Increased SE, belief that one has special talents, powers, or abilities o Distractibility, attention easily diverted
    • Excessive involvement in activities that are likely to have painful consequences, such as reckless spending, sexual indiscretions, or unwise business investments
    • Symptoms are present most of the day, nearly everyday  For a manic episode:
    • Symptoms last 1 week, require hospitalization, or include psychosis o Symptoms cause significant distress or functional impairment  For a hypomanic episode:
    • Symptoms last at least 4 days
    • Clear changes in functioning are observable to others, but impairment is not marked o No psychotic symptoms are present

Subtypes of Depressive Disorders and Bipolar Disorders

  • Mood disorders are highly heterogeneous – people diagnosed with the same disorder may show very different symptoms
  • Rapid cycling = pattern of episodes over time (aka seasonal specifier) *for bipolar only
  • Melancholic = episode specifier specific to depression

Etiology of Mood Disorders

  • Etiology studies tend to focus on MDD and bipolar-I

Genetic Factors

  • Heritability estimate of 37% for MDD (twin studies) *higher estimate when studying more severe samples
  • Bipolar is among the most heritable disorders – heritability estimate of 93%
  • Unlikely that there is a single gene that explains mood disorders – due to high heterogeneity
  • GWAS studies for responsible genes have been inconclusive o DRD 4.2 gene influences dopamine function, related to MDD
  • Have identified several genetic polymorphisms related to bipolar disorder
  • Polymorphism of serotonin transporter gene is related to MDD o Greater risk for depression after a stressful life event with this polymorphism o Having at least one short allele associated with elevated reactivity to stress  Neurotransmitters:
    • Norepinephrine, dopamine and serotonin are related to mood disorders
    • People with depression are less responsive than others to drugs that increase dopamine levels
    • It is thought that the functioning of dopamine might be lowered in depression o Dopamine is involved in the reward system of the brain = guides pleasure, motivation, and energy in the context of opportunities to obtain rewards
    • Drugs that increase dopamine levels are found to trigger manic symptoms in bipolar individuals *overly sensitive dopamine receptors
    • To lower serotonin levels, deplete levels of tryptophan *major precursor or serotonin
      • Causes temporary depressive symptoms in those with family history for depression or depressive symptoms
    • Bipolar disorder may be related to diminished sensitivity of serotonin receptors o Medication alters levels immediately but takes 2-3 weeks for relief o New modes focus on sensitivity of post-synaptic receptors

Brain Function: Regions Involved in Emotion

  • 5 primary brain structures most studied in depression: amygdala, anterior cingulate, dorsolateral prefrontal cortex, hippocampus, and the striatum
  • Amygdala – helps assess how salient/emotionally important a stimulus is o People with MDD have more intense reactions to stimuli with emotion
  • MDD associated with greater activation of anterior cingulate and diminished activation of the hippocampus & dorsolateral prefrontal cortex when viewing negative stimuli
  • MDD – diminished activation of striatum – specifically when receiving positive feedback o Nucleus accumbens – central component of rewards system, plays a key role in motivation to pursue rewards
  • Bipolar I – elevated responsiveness in the amygdala, increased activity of anterior cingulate, diminished activity of hippocampus and dorsolateral prefrontal cortex o High activation of striatum***

The Neuroendocrine System: Cortisol Dysregulation

  • HPA axis overactive during MDD *stress reactivity **overactive amygdala
  • Overactive amygdala sends signals to HPA axis, triggers release of cortisol (stress hormone)
  • Cortisol increases immune system activity to help body prepare for threats
  • Cushing’s syndrome = causes over-secretion of cortisol, frequent depressive symptoms
  • 80% of people hospitalized for depression show poor regulation of HPA system

Social Factors in Depression: Childhood Adversity, Life Events, and Interpersonal Difficulties

  • Often interpersonal factors precede onset of depression
  • Childhood adversity: parental death, physical abuse, sexual abuse increases risk that later the individual will develop depression *depressive symptoms likely will be chronic
  • Child abuse linked to anxiety even more strongly than to depression
  • Common stressful life events for triggering depressive symptoms include: losing a job, a key friendship or a romantic relationship
  • Lack of social support is common amongst depressed individuals *lessens ability to handle stress
  • Expressed emotion = a family member’s critical or hostile comments toward or emotional overinvolvement with the person with depression o High EE strongly predicts relapse in depression
  • Excessive need for reassurance has been found to be predictive of depression
  • Low social competence among elementary school children is a predictor of depression, poorinterpersonal problem solving skills among adolescents
  • Marital conflict can predict depression

Psychological Factors in Depression  Neuroticism:

  • Neuroticism = a personality trait that involves the tendency to experience frequent and intense negative affect *predicts the onset of depression
  • Explains part of genetic vulnerability to depression o Also associated with anxiety  Cognitive Theories:
  • Pessimistic and self-critical thoughts are major causes of depression o Beck’s Theory:
    • Depression is associated with a negative triad = negative views of the self, their world, and the future (hopelessness)
    • In childhood, people with depression acquired negative schemas through experiences
    • Negative schema is activated whenever the person encounters situations similar to those that originally caused the schema to form
    • Cause cognitive biases = tendencies to process info in certain negative ways
    • Depression associated with a tendency to stay focused on negative info once it is initially noticed
  • Hopelessness Theory:
    • Hopelessness theory = most important trigger of depression is hopelessness *the belief that desirable outcomes will not occur and that there is nothing a person can do to change this
    • Attributions = the explanations a person forms about why a stressor has occurred:
  • 1) Stable (permanent) vs. unstable (temporary) causes
  • 2) Global vs. specific causes
  • Stable and global Attributional style more likely linked to depression
    • Rumination Theory:
      • Rumination = tendency to repetitively dwell on sad experiences and thoughts, or to chew on material again and again
      • Most detrimental form: to brood regretfully about why a sad event happened
      • Tendencies to ruminate have been found to predict onset of MD episodes
      • Women tend to ruminate more than men
      • Rumination increases negative moods, particularly when people focus on negative aspects of their mood and their self
      • Evolutionarily adaptive to focus on negative events in order to solve problems

Social and Psychological Factors in Bipolar Disorder

  • Most people who experience a manic episode will also experience a major depressive episode  Depression in Bipolar Disorders:
    • Triggers of depression in bipolar disorder are similar to those of MDD
    • Negative life events are important triggers, neuroticism, negative cognitive styles, expressed emotion, lack of social support  Predictors of Mania:
    • Reward sensitivity:
      • Disturbance in reward system of the brain
      • Highly responsive to rewards
      • Life events involving success may trigger cognitive changes in confidence
      • Then spirals into excessive goal pursuit, which helps trigger manic symptoms o Sleep deprivation:
      • Sleep deprivation can precede onset of manic episodes
      • Protecting sleep can help reduce symptoms of bipolar disorder

Treatment of Mood Disorders

  • About 50% of people who meet diagnostic criteria for major depression do not receive care

Psychological Treatment of Depression

  • Interpersonal Psychotherapy (IPT):
    • Builds on the idea that depression is closely tied to interpersonal problems o Examine major interpersonal problems
    • Focus on 1 or 2 issues with the goal of helping the person identify his feelings about these issues, make important decisions and effect changes to resolve problems related to these issues
    • Typically brief treatment (16 sessions)
    • Techniques: discussing interpersonal problems, exploring negative feelings and encouraging their expression, improving verbal/nonverbal communications/problem solving
    • Effective in relieving MDD and prevents relapse when continued after recovery o 1) Short-term psychodynamic theory 2) Focus on current relationships  Cognitive Therapy (CT):
    • Depression is caused by negative schema and cognitive biases o Aims to alter maladaptive thought patterns o Client taught to understand how powerfully our thoughts can influence our moods o Help client change his opinions of himself
    • Teaches client to challenge negative beliefs and to learn strategies that promote making realistic/positive assumptions
    • Thought-monitoring homework ***emphasis on cognitive restructuring
    • Behavioural activation (BA) – people are encouraged to engage in pleasant activities that might bolster positive thoughts about one’s self and life
    • Mindfulness-based cognitive therapy (MBCT) = focuses on preventing relapse after successful treatment
      • Based on the assumption that a person becomes vulnerable to relapse because of repeated associations between sad mood and patterns of self-devaluing, hopeless thinking during MD episodes
      • Goal: teach people to reorganize when they start to become depressed and to try adopting a decentered perspective
    • = Viewing their thoughts as mental events rather than as core aspects of the self or accurate reflections of reality

 Detached relationship to depression-related thoughts/feelings o Monitor and identify automatic thoughts, replace negative with neutral/positive  Behavioural Activation Therapy (BA):

  • Originally developed as a standalone treatment
  • Based on idea that many risk factors for depression interfere with receiving positive reinforcement
  • Goal: to increase participation in positively reinforcing activities to disrupt depression  Behavioural Couples Therapy:
  • Depression is often tied to relationship problems
  • Researchers work with both members of a couple to improve communication and relationship satisfaction

Psychological Treatment of Bipolar Disorder

  • Medication is a necessary component, can have psychological treatment as a supplement
  • Psychotherapy can also help reduce bipolar’s depressive symptoms
  • Psychoeducational approaches = help people learn about the symptoms of the disorder, expected time course of symptoms, biological/psychological triggers for symptoms, and treatment strategies
  • Can help people adhere to treatment with medications (e.g. lithium)
  • Half of patients on medication for bipolar do not take medication consistently
  • Psycho-ed helps patients understand rationale for taking medication
  • CT and family-focused therapy (FFT) have received strong support
  • FFT educates the family about the illness, enhances family communication and develop problemsolving skills

Biological Treatment of Mood Disorders

  • Electroconvulsive Therapy for Depression (ECT):
    • Only used to treat MDD that has not responded to medication o Induces a momentary seizure
    • Bilateral ECT = electrodes placed on each side of the forehead
    • Unilateral ECT = currents passes only through the non-dominant (typically right) cerebral hemisphere *less pronounced side effects
    • Patient is now given a muscle relaxant prior to ECT so they sleep through it o Receive 6-12 treatments typically
    • More powerful than antidepressant medication especially when there are psychotic features o Associated deficiencies in cognitive functioning  Medications for Depressive Disorders:
    • Most commonly used and best-researched treatments for depression o 75% of treated depression patients are prescribed antidepressants o 3 categories of antidepressants:
      • Monoamine oxidase inhibitors (MAOIs)
      • Tricyclic antidepressants
      • Selective serotonin reuptake inhibitors (SSRIs) o Recommended treatment for at least 6 months after an episode ends o Concern: may not be more affective than placebos for mild/moderate symptoms of MDD o 40% of patients on antidepressants stop taking them after the 1st month *tough side effects o MAOIs have possible life threatening side effects if combined with certain foods o SSRIs are most common
    • Transcranial Magnetic Stimulation (TMS) for Depression:
      • Allowed for patients who have failed to respond to a first antidepressant but not yet tried a second
      • Electromagnetic coil placed against scalp, pulses of magnetic energy used to increase activity in dorsolateral prefrontal cortex (30 mins, for 5-10 days)
      • Can help relieve treatment resistant depression
      • Star-D sequenced treatment alternatives to relieve depression  Comparing Treatments for Major Depressive Disorder:
      • Combining psychotherapy and antidepressant use raises odds of recovery by 10-20% o Antidepressants work more quickly than psychotherapy  Medications for Bipolar Disorder:
      • Mood-stabilizing medications = medications that reduce manic symptoms o Lithium = naturally occurring chemical element, first mood stabilizer identified o Most medicated patients still experience mild manic/depressive symptoms o 40% of people relapsed while taking lithium, 60% while taking a placebo o Lithium levels are toxic if too high *ingestions requires regular blood tests o 2 other types of medications for acute mania: *also help relieve depression
        • Anticonvulsant (antiseizure) medication (divalproex sodium)
        • Antipsychotic medication (olanzapine)
        • Recommended for those who don’t respond to lithium o Patients often begin with lithium alongside psychotherapy (lithium takes a long time to start working)
      • A final note on treatment:
        • Deep brain stimulation = involves implanting electrodes into the brain, applying small current to the electrodes, can manipulate activity to those brain regions
        • Studies done with patients who have not responded to other forms of treatment o 10-20% better chance at recovery when combining medication w/therapy o Medication takes 2-3 weeks to kick in
        • CT can be as effective as medications for severe depression, more effective than medication at preventing relapse Suicide
      • Suicidal ideation = thoughts of killing oneself, more common than attempted/completed suicide
      • Most suicide attempts do not result in death
      • Suicide attempt = behaviour intended to kill oneself
      • Suicide = involves behaviours that are intended to cause death and actually do so
      • Non-suicidal self injury = involves behaviours meant to cause immediate bodily harm but are not intended to cause death

Epidemiology of Suicide and Suicide Attempts

  • 9% report ideation (worldwide), 2.5% have made at least 1 attempt
  • Suicide rates are underestimated – often circumstances of some deaths are ambiguous
  • Every 20 minutes someone in the US dies from suicide
  • Men (adolescent males especially) are 4 times more likely to kill themselves than women
  • Women are more likely to make suicidal attempts that do not result in death
  • Men choose to shoot/hang themselves, women are more likely to use pills
  • Suicide rate increases in old age *white males over 50 have highest rate in US
  • Being divorced or widowed increased risk 4 or 5 fold
  • 6% of undergrads, 4% grad students seriously contemplate attempting o 1 in 12 make a plan, ½ don’t tell anyone

Risk Factors for Suicide

  • Psychological Disorders:
    • Many individuals with mood disorders have suicidal thoughts o More than 50% of those who attempt, are depressed at the time o 15% of those hospitalized with depression end up killing themselves o 90% of attempts are suffering from some psyc disorder
      • 5-7% bipolar, 5% schizophrenia, impulse control disorders, substance use disorders,

PTSD, borderline personality disorder, panic disorders, eating disorders

  • Most likely when a person is experiencing comorbid depression o Most people with psyc disorders do not die from suicide  Neurobiological Factors:
  • Heritability accounts for 48% of suicide attempts o Serotonin (violent suicide) and cortisol are important factors
  • Social Factors:
    • Suicide rates have increased over the past 100 years (economic recession) o Major effect from media reports on suicide (e.g. after Marilyn Monroe’s suicide) o Social isolation and lack of social belonging are powerful predictors  Psychological Factors:
    • Related to poor problem solving skills
    • Difficulty solving problems leads to increased vulnerability to hopelessness *strongly tied to suicidality
    • Many think about suicide, only few act on those thoughts **impulsivity

Preventing Suicide

  • Talking about suicide might help relieve a sense of isolation  Treating the Associated Psychological Disorder:
    • Most people who kill themselves are suffering from a psyc disorder o Decrease in psyc disorder symptoms also decreases risk of suicide
    • Many antidepressants and other medications for mood disorders reduce risk of suicide  Treating Suicidality Directly:
    • Cognitive behavioural approaches are most promising
    • Reduce risk of future attempt by 50% in those who have already attempted/failed o Also reduce suicidal ideation
  • Broader Approaches to Suicide Prevention:
    • Rates of suicide are much higher in the military *use this setting to conduct research on prevention methods
    • Public health prevention tries to make it more difficult to access means used for suicide