About Depression

Depression is a common illness that causes feelings of sadness, hopelessness, or loss. Depression is a medical illness and is treatable. When depression is severe and lasts longer than 2 weeks, it is referred to as major depression. While everyone feels sad or low from time to time, a person suffering from major depression experiences symptoms that interfere with their ability to work, sleep, study, eat, and enjoy life. An episode can occur only once in a person’s lifetime, but more often, a person has several episodes.
It's estimated that about 350 million people worldwide live with depression. Many often do not want to admit it. Shame and a sense of personal inadequacy are still attached to it. Many cases of depression can be traced to specific life events and are successfully treated through a combination of medication and psychotherapy.

What Causes Depression?

Although it's the subject of much research, the medical cause of depression continues to remain uncertain. Depressive illnesses are disorders of the brain. Brain-imaging technologies, such as magnetic resonance imaging (MRI), have shown that the brains of people who have depression look different than those of people without depression. The parts of the brain involved in mood, thinking, sleep, appetite, and behavior appear different. But these images do not reveal why the depression has occurred. They also cannot be used to diagnose depression. Researchers believe a combination of factors most likely cause a person to suffer from depression. These include:

• Life stressors (loss of a loved one, unemployment and job stress, difficulty with school)
• Biological differences in the brain
• Neurotransmitters and hormonal effects
• Inheritance (genetics)
• Early childhood trauma or loss

Signs and Symptoms

People with depressive illnesses do not all experience the same symptoms. The severity, frequency, and duration of symptoms vary depending on the individual and their particular illness.
Signs and symptoms include:

• Persistent sad, anxious, or "empty" feelings
• Feelings of guilt, worthlessness, or helplessness
• Irritability, restlessness
• Loss of interest in activities or hobbies once pleasurable, including sex
• Fatigue and decreased energy
• Difficulty concentrating, remembering details, and making decisions
• Insomnia, early-morning wakefulness, or excessive sleeping
• Overeating, or appetite loss
• Thoughts of suicide, suicide attempts
• Aches or pains, headaches, cramps, or digestive problems that do not ease even with treatment.

Diagnosing Depression

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.
There isn't a single lab or imaging test that identifies someone as suffering from depression. Brain scans have shown changes that occur in a depressed person's brain, but they are not used as a diagnostic tool. The diagnosis is based primarily on patients' descriptions of their symptoms. Sometimes depression is so readily apparent that the diagnosis is relatively straightforward and unambiguous. However, in many cases people complain about general feelings of sadness or fatigue for no specific reason, yet may have clinically-significant depression and need treatment.