National Institute of Mental Health
Major depressive disorder is one of the most common mental disorders in the United States. Each year about 6.7% of U.S adults experience major depressive disorder. Women are 70 % more likely than men to experience depression during their lifetime. Non-Hispanic blacks are 40% less likely than non-Hispanic whites to experience depression during their lifetime. The average age of onset is 32 years old. Additionally, 3.3% of 13 to 18 year olds have experienced a seriously debilitating depressive disorder.
“I started missing days from work, and a friend noticed that something wasn’t right. She talked to me about the time she had been really depressed and had gotten help from her doctor.”
Depression, even the most severe cases, can be effectively treated. The earlier that treatment can begin, the more effective it is.
The first step to getting appropriate treatment is to visit a doctor or mental health specialist. Certain medications, and some medical conditions such as viruses or a thyroid disorder, can cause the same symptoms as depression. A doctor can rule out these possibilities by doing a physical exam, interview, and lab tests. If the doctor can find no medical condition that may be causing the depression, the next step is a psychological evaluation.
The doctor may refer you to a mental health professional, who should discuss with you any family history of depression or other mental disorder, and get a complete history of your symptoms. You should discuss when your symptoms started, how long they have lasted, how severe they are, and whether they have occurred before and if so, how they were treated. The mental health professional may also ask if you are using alcohol or drugs, and if you are thinking about death or suicide.
Other illnesses may come on before depression, cause it, or be a consequence of it. But depression and other illnesses interact differently in different people. In any case, co-occurring illnesses need to be diagnosed and treated.
Anxiety disorders, such as post-traumatic stress disorder (PTSD), obsessive-compulsive disorder, panic disorder, social phobia, and generalized anxiety disorder, often accompany depression. PTSD can occur after a person experiences a terrifying event or ordeal, such as a violent assault, a natural disaster, an accident, terrorism or military combat. People experiencing PTSD are especially prone to having co-existing depression.
Alcohol and other substance abuse or dependence may also co-exist with depression. Research shows that mood disorders and substance abuse commonly occur together.
Depression also may occur with other serious medical illnesses such as heart disease, stroke, cancer, HIV/AIDS, diabetes, and Parkinson’s disease. People who have depression along with another medical illness tend to have more severe symptoms of both depression and the medical illness, more difficulty adapting to their medical condition, and more medical costs than those who do not have co-existing depression. Treating the depression can also help improve the outcome of treating the co-occurring illness.