Major Depressive Disorder

A mental health disorder characterized by persistently depressed mood or loss of interest in activities, causing significant impairment in daily life.
Possible causes include a combination of biological, psychological, and social sources of distress. Increasingly, research suggests these factors may cause changes in brain function, including altered activity of certain neural circuits in the brain.
The persistent feeling of sadness or loss of interest that characterizes major depression can lead to a range of behavioral and physical symptoms. These may include changes in sleep, appetite, energy level, concentration, daily behavior, or self-esteem. Depression can also be associated with thoughts of suicide.
The mainstay of treatment is usually medication, talk therapy, or a combination of the two. Increasingly, research suggests these treatments may normalize brain changes associated with depression.


Cluster Number:
Wiki Number: PW115
Diagnosis: Major Depressive Disorder
US Patients:
World Patients: 163 Mil; 2% of world population
Sex Ratio: M;W2
Age Onset: 20s-30s; The average duration is 23 weeks, with three more during lifetime. ½ of patients will not have another episode.
Brain Area: 102 variations in the genome linked to depression; There is an extensive description of possible brain affects on depression.
Symptoms: Has at least two weeks of depressive mood; inability to enjoy pleasure; rumination; reduced sex drive, insomnia and hypersomnia
Progression: weight and appetite may be low; fatigue, social withdrawal, suicidal thoughts; delusions or sometimes hallucinations
Causes: 40%-hereditary; response to stressors, childhood abuse. The article claims general physicians miss 2/3 of depression diagnoses.
Medications: Antidepressants-for the deeply depressed; electroconvulsive therapy
Therapies: Counseling; transcranial magnetic stimulation, light therapy, exercise, light therapy,


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