Depression can affect anyone—even a person who appears to live in relatively ideal circumstances.
Several factors can play a role in depression:
- Biochemistry: Differences in certain chemicals in the brain may contribute to symptoms of depression.
- Genetics: Depression can run in families. For example, if one identical twin has depression, the other has a 70 percent chance of having the illness sometime in life.
- Personality: People with low self-esteem, who are easily overwhelmed by stress, or who are generally pessimistic appear to be more likely to experience depression.
- Environmental factors: Continuous exposure to violence, neglect, abuse or poverty may make some people more vulnerable to depression.