There's still a stigma surrounding depression, says neuropsychologist Marsha Lucas, PhD. In this WisePatient video, she explains how social taboos prevent many people from seeking treatment for depression.
Depression affects 7% of the population, including 10% of the population over the age of 18, during a single year. In the U.S., 19 million people will suffer from mood disorders this year.
Major depression is a major cause of disability in the U.S. and worldwide. Unipolar major depression is second only to coronary heart disease as the major illness contributing to disability in major market economies, and unipolar major depression accounts for 7% of disability adjusted life years, an international standard measure of disability.
Each year, 12% of American women and 7% of American men will experience depression. Over their lifetimes, approximately 20% of women and 10% of men will experience major depression. Whether examined for one year or for the entire life span, approximately twice as many women as men will be affected. Women between the ages of 18 and 45 compose the largest proportion of people with major depression.
People who are depressed, by definition, do not feel good. They experience low energy, sleep poorly and feel helpless, hopeless and often unwilling to interact with others. As a first line of self-medication, many people turn to drinking alcohol or taking either legal or illegal stimulant drugs. This is actually the worst possible strategy for dealing with depression. Alcohol and some drugs are depressants. Depressed mood can be a direct outcome of substance abuse. Conversely, use of alcohol or of some drugs by people with a depressive disorder may increase the severity of their depressive symptoms.
Studies have shown that genetic makeup plays a role in the etiology of depression, but no study has indicated that depression is solely based on a person's genes. Family, twin and adoption studies have indicated that genetic factors are involved in the development of mood disorders (affective disorders). Potential genetic markers (that is, specific traits present on the genes) have been identified on specific chromosomes. Some of these markers are directly linked to neurobiological processes, believed to be related to the occurrence of major depression.
The neurotransmitters involved in these neurobiological processes are chemical substances that transmit or block impulses among the nerve cells (neurons) in the brain. Norepinephrine and serotonin have been the most widely studied neurotransmitters in depression research. These may be thought of as up, or excitatory, neurotransmitters. Studies of the effects of antidepressant medications used to treat depression suggest that depression is characterized by low levels of both serotonin and norepinephrine. Depletion of up neurotransmitters is associated with feeling down and depressed.