Depressive disorders Home A-Z Health Information Health Library A-Z Depressive Disorders Overview Depressive disorders, commonly referred to as depression are among the most prevalent psychiatric disorder. Usually, they co-exists in individuals suffering from chronic (long term) illnesses such as diabetes mellitus, cardiac illnesses, stroke, thyroid disorders and cancers. Causes Depressive disorders can be caused by a variety of factors. These include the following:Genetics PsychologicalEnvironmentalUnderlying illness Types There are several types of depressive disorders:MajorRecurrentPersistent (dysthymia)BipolarDepressive disorder due to medical conditionPremenstrual dysphoric disorder. Symptoms Symptoms of major depressive disorder are (any 5 of the following, persisting for more than 2 weeks): Persistent depressed moodLoss of interest or loss of pleasure in previously pleasurable activitiesReduced or excessive sleepReduced or excessive appetiteWeight loss or gainLoss of energyRestlessness or slowing downDifficulty maintaining concentration or indecisivenessRecurrent thoughts of death or suicidal ideas/plan/attempt. Diagnosis Diagnosis methods include:Physical examinationPsychiatric evaluationBlood tests to rule out other conditions Treatment Care for depression includesMedicationsPsychological treatments.