What Is Depression?
Depression is a common illness worldwide, with more than 264 million people affected(1). Depression is different from usual mood fluctuations and short-lived emotional responses to challenges in everyday life. Especially when long-lasting and with moderate or severe intensity, depression may become a serious health condition. It can cause the affected person to suffer greatly and function poorly at work, at school and in the family. At its worst, depression can lead to suicide. Close to 800 000 people die due to suicide every year. Suicide is the second leading cause of death in 15-29-year-olds.
Depression is a serious medical illness that negatively affects how you feel, the way you think and how you act. Fortunately, it is also treatable. Depression causes feelings of sadness and/or a loss of interest in activities once enjoyed. It can lead to a variety of emotional and physical problems and can decrease a person’s ability to function at work and at home.
They can include:
- Trouble concentrating, remembering details, and making decisions
- Feelings of guilt, worthlessness, and helplessness
- Pessimism and hopelessness
- Insomnia, early-morning wakefulness, or sleeping too much
- Loss of interest in things once pleasurable, including sex
- Overeating, or appetite loss
- Aches, pains, headaches, or cramps that won’t go away
- Digestive problems that don’t get better, even with treatment
- Persistent sad, anxious, or “empty” feelings
- Suicidal thoughts or attempts
What Are the Main Causes of Depression?
There are a number of factors that may increase the chance of depression, including the following:
- Abuse. Past physical, sexual, or emotional abuse can increase the vulnerability to clinical depression later in life.
- Certain medications. Some drugs, such as isotretinoin (used to treat acne), the antiviral drug interferon-alpha, and corticosteroids, can increase your risk of depression.
- Conflict. Depression in someone who has the biological vulnerability to develop depression may result from personal conflicts or disputes with family members or friends.
- Death or a loss. Sadness or grief from the death or loss of a loved one, though natural, may increase the risk of depression.
- Genetics. A family history of depression may increase the risk. It’s thought that depression is a complex trait, meaning that there are probably many different genes that each exert small effects, rather than a single gene that contributes to disease risk. The genetics of depression, like most psychiatric disorders, are not as simple or straightforward as in purely genetic diseases such as Huntington’s chorea or cystic fibrosis.
- Major events. Even good events such as starting a new job, graduating, or getting married can lead to depression. So can moving, losing a job or income, getting divorced, or retiring. However, the syndrome of clinical depression is never just a “normal” response to stressful life events.
- Other personal problems. Problems such as social isolation due to other mental illnesses or being cast out of a family or social group can contribute to the risk of developing clinical depression.
- Serious illnesses. Sometimes depression co-exists with a major illness or may be triggered by another medical condition.
- Substance abuse. Nearly 30% of people with substance abuse problems also have major or clinical depression. Even if drugs or alcohol temporarily make you feel better, they ultimately will aggravate depression.
There isn’t a “depression test” a doctor can use to see if you have it. So figuring that out often starts with a thorough history and physical exam.
Your doctor will want to know:
- When your symptoms started
- How long they’ve lasted
- How severe they are
- If depression or other mental illnesses run in your family
- If you have a history of drug or alcohol abuse
You’ll also be asked if you’ve had similar symptoms of depression before, and if so, how it was treated.