DSM-5 Criteria:<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n1) Depressed mood for most of the day more than half of the time for 2 years (1 for children\/adolescents)<\/p>\n
2) At least 2 of the following during that time:<\/p>\n
\uf0b7 Poor appetite\/overeating, Sleeping too much\/too little, Low energy, Poor SE, Trouble concentrating\/making decisions, Feelings of hopelessness<\/p>\n
3) The symptoms do not clear for more than 2 months at a time<\/p>\n
4) Bipolar disorders are not present \uf0b7 Other DSM-5 Depressive Disorders:<\/p>\n
\n- Disruptive mood dysregulation disorder<\/strong> = newly defined depressive disorder, a diagnosis specific to children and adolescents<\/li>\n
- Premenstrual dysphoric disorder<\/strong> = moved from DSM-IV appendix to main diagnostic section \uf0b7 Epidemiology and Consequences of Depressive Disorders:<\/li>\n
- MDD \u2013 one of the most common psyc disorders (16.2% US will meet criteria at some point)<\/li>\n
- 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<\/li>\n
- 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<\/li>\n
- Korea \u2013 less likely to describe sad mood\/suicidal thoughts o Latino culture \u2013 complaints of nerves\/headaches<\/li>\n
- Asian culture \u2013 reports of weakness, fatigue, and poor concentration<\/li>\n
- 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<\/li>\n
- 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<\/li>\n<\/ul>\n
Bipolar Disorders<\/p>\n
\n- 3 forms (DSM-5): bipolar-I, bipolar-II, cyclothymic disorder<\/li>\n
- Manic symptoms are the defining feature (most also experience depression)<\/li>\n
- Episode of depression is not required for bipolar-I, it is required for bipolar-II<\/li>\n
- Mania<\/strong> = a state of intense elation, irritability, or activation accompanied by other symptoms<\/li>\n
- Flight of ideas<\/strong> = difficult to interrupt, shifting rapidly from topic to topic<\/li>\n
- Stop sleeping, extremely self-confident, incredibly energetic<\/li>\n
- Risky sexual activities, overspending, reckless driving<\/li>\n
- Hypomania<\/strong> = less extreme than mania (under mania), does not involve significant impairment, involves a change in functioning that does not cause serious problems \uf0b7 Bipolar I Disorder:<\/strong>\n
\n- Formerly known as manic-depressive disorder<\/li>\n
- Diagnosis: includes a single episode of mania during the course of a person\u2019s life o Bipolar episodes tend to recur<\/li>\n
- More than 50% experience 4+ episodes during their life time o Toughest to diagnose<\/li>\n<\/ul>\n<\/li>\n
- Bipolar II Disorder:<\/strong>\n
\n- Midler form<\/li>\n
- Must experience at least one major depressive episode and at least one episode of hypomania (and no lifetime episode of mania) \uf0b7 Cyclothymic Disorder:<\/strong><\/li>\n
- Aka cyclothymia \u2013 a second chronic mood disorder (like PDD)<\/li>\n
- 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\u2019t clear for more than 2 months at a time \uf0b7 Epidemiology and Consequences of Bipolar Disorders:<\/li>\n
- 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<\/li>\n
- 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<\/li>\n
- 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<\/strong> for Manic and Hypomanic Episodes: \uf0b7 Distinctly elevated or irritable mood<\/li>\n<\/ul>\n<\/li>\n
- Abnormally increased activity or energy<\/li>\n
- At least 3 of the following are noticeably changed from baseline (4 if irritable mood):\n
\n- Increase in goal-directed activity or psychomotor agitation o Unusual talkativeness \u2013 rapid speech<\/li>\n
- Flight of ideas or subjective impression that thoughts are racing o Decreased need for sleep<\/li>\n
- Increased SE, belief that one has special talents, powers, or abilities o Distractibility, attention easily diverted<\/li>\n
- Excessive involvement in activities that are likely to have painful consequences, such as reckless spending, sexual indiscretions, or unwise business investments<\/li>\n
- Symptoms are present most of the day, nearly everyday \uf0b7 For a manic episode<\/strong>:<\/li>\n
- Symptoms last 1 week, require hospitalization, or include psychosis o Symptoms cause significant distress or functional impairment \uf0b7 For a hypomanic episode<\/strong>:<\/li>\n
- Symptoms last at least 4 days<\/li>\n
- Clear changes in functioning are observable to others, but impairment is not marked o No psychotic symptoms are present<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
Subtypes of Depressive Disorders and Bipolar Disorders<\/p>\n
\n- Mood disorders are highly heterogeneous \u2013 people diagnosed with the same disorder may show very different symptoms<\/li>\n
- Rapid cycling<\/strong> = pattern of episodes over time (aka seasonal specifier) *for bipolar only<\/li>\n
- Melancholic<\/strong> = episode specifier specific to depression<\/li>\n<\/ul>\n
Etiology of Mood Disorders <\/strong><\/p>\n
\n- Etiology studies tend to focus on MDD and bipolar-I<\/li>\n<\/ul>\n
Genetic Factors<\/p>\n
\n- Heritability estimate of 37% for MDD (twin studies) *higher estimate when studying more severe samples<\/li>\n
- Bipolar is among the most heritable disorders \u2013 heritability estimate of 93%<\/li>\n
- Unlikely that there is a single gene that explains mood disorders \u2013 due to high heterogeneity<\/li>\n
- GWAS studies for responsible genes have been inconclusive o DRD 4.2 gene influences dopamine function, related to MDD<\/li>\n
- Have identified several genetic polymorphisms related to bipolar disorder<\/li>\n
- 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 \uf0b7 Neurotransmitters:\n
\n- Norepinephrine, dopamine and serotonin are related to mood disorders<\/li>\n
- People with depression are less responsive than others to drugs that increase dopamine levels<\/li>\n
- It is thought that the functioning of dopamine might be lowered in depression o Dopamine is involved in the reward system<\/strong> of the brain = guides pleasure, motivation, and energy in the context of opportunities to obtain rewards<\/li>\n
- Drugs that increase dopamine levels are found to trigger manic symptoms in bipolar individuals *overly sensitive dopamine receptors<\/li>\n
- To lower serotonin levels, deplete levels of tryptophan<\/strong> *major precursor or serotonin\n