What were the causes of worldwide depression?

There is not just one cause of depression. It is a complex disease that can occur as a result of a multitude of factors. For some, depression occurs due to a loss of a loved one, a change in one's life, or after being diagnosed with a serious medical disease. For others, depression just happened, possibly due to their family history. Factors involved in causing depression, include: A history of depression in the family: It is believed that depression is passed genetically from generation to generation, although the exact way this occurs is not known. Grief from the death or loss of a loved one. Personal disputes, like conflict with a family member. Physical, sexual, or emotional abuse. Major events that occur in everyone's lives, such as moving, graduating, changing jobs, getting married or divorced, retiring, etc. Serious illness: depressed feelings are a common reaction to many medical illnesses. Certain medications Substance abuse: close to 30% of people with substance abuse problems also have major depression. Other personal problems: these may come in the forms of social isolation due to other mental illnesses, or being cast out of a family or social circle.