31/07/2023
psychiatric and mental health 3,2
Clinical_medicine
Major Depressive Disorder
🩺 definition
• history of one or more Major Depressive Episodes
🩺 epidemiology
• prevalence: male 2-4%, female 5-9% (M:F = 1:2)
• mean age of onset: ~ 30 years
🩺 etiology
• genetic
65-75% MZ twins
14-19% DZ twins
• neurotransmitter dysfunction at level of synapse (decreased activity of serotonin,
norepinephrine, dopamine)
• psychodynamic (e.g. low self-esteem)
• cognitive (e.g. negative thinking)
🩺 risk factors
• s*x: female
• age: onset in 25-50 age group
• family history: depression, alcohol abuse, sociopathy
• childhood experiences: loss of parent before 11 years old, negative home environment (abuse, neglect)
• personality: insecure, dependent, obsessional
• recent stressors (illness, financial, legal)
• postpartum
• lack of intimate, confiding relationships (social isolation)
🩺 diagnosis
• history of one or more MDE
• absence of a previous manic, hypomanic, or mixed episode
🩺 classification
• MDD, with psychotic features (with hallucinations or delusions; these may be mood congruent)
• MDD, chronic (lasting 2 years or more)
• MDD, with melancholic features (quality of mood is distinctly depressed, mood is worse in the
morning, early morning wakening, severe weight loss, excessive guilt, psychomotor retardation)
• MDD, with atypical features (increased sleep, weight gain, leaden paralysis, chronic
rejection sensitivity)
• MDD, with postpartum onset (see Postpartum Mood Disorders section)
• MDD, with seasonal pattern (pattern of onset at same time each year)
🩺 depression in the elderly
• accounts for about 50% of acute psychiatric admissions in the elderly
• affects about 15% of community residents > 65 years old
• high su***de risk due to increased lethality and decreased
communication of su***de attempt due to social isolation
• su***de peak: males aged 80-90; females aged 50-65
• often present with somatic complaints (e.g. changes in weight, sleep,
energy) or anxiety symptoms rather than classic depression
🩺 treatment
• biological: antidepressants, lithium, electroconvulsive therapy (ECT)
• psychological: psychodynamic, cognitive, behavioural, family, and group therapy
• social: vocational rehabilitation, social skills training
🩺 differential diagnosis for MDE
• adjustment disorder with depressed mood
• bereavement
• dementia
• mood disorder due to GMC
• substance induced mood disorder
• anxiety disorder