Depression

According to the DSM-IV, a manual used to diagnose mental disorders, depression occurs when you have at least five of the following nine symptoms at the same time:

a depressed mood during most of the day, particularly in the morning
fatigue or loss of energy almost every day
feelings of worthlessness or guilt almost every day
impaired concentration, indecisiveness
insomnia or hypersomnia (excessive sleeping) almost every day
markedly diminished interest or pleasure in almost all activities nearly every day
recurring thoughts of death or suicide (not just fearing death)
a sense of restlessness — known as psychomotor agitation — or being slowed down — retardation
significant weight loss or gain (a change of more than 5% of body weight in a month)

With major or clinical depression, one of the key signs is either depressed mood or loss of interest. For a diagnosis of depression, these signs should be present most of the day either daily or nearly daily for at least two weeks. In addition, the depressive symptoms need to cause clinically significant distress or impairment. They cannot be due to the direct effects of a substance, for example, a drug or medication. Nor can they be the result of a medical condition such as hypothyroidism. Finally, if the symptoms occur within two months of the loss of a loved one, they will not be diagnosed as depression.

According to the National Institute of Mental Health, people with depressive illnesses do not all experience the same symptoms. How severe they are, how frequent, and how long they last will vary. It depends on the individual and his or her particular illness.

Here are common symptoms people with depression experience:

difficulty concentrating, remembering details, and making decisions
fatigue and decreased energy
feelings of guilt, worthlessness, and/or helplessness
feelings of hopelessness and/or pessimism
insomnia, early morning wakefulness, or excessive sleeping
irritability, restlessness
loss of interest in activities or hobbies once pleasurable, including sex
no pleasure left in life any more
overeating or appetite loss
persistent aches or pains, headaches, cramps, or digestive problems that do not ease even with treatment
persistent sad, anxious, or “empty” feelings
thoughts of suicide, suicide attempts

It is estimated that, by the year 2020, major depression will be second only to ischemic heart disease in terms of the leading causes of illness in the world. But patients with depression sometimes fail to realize (or accept) that there is a physical cause to their depressed moods. As a result, they may search endlessly for external causes.

In the U.S., about 14.8 million adults suffer from major depression, according to the National Institute of Mental Health. Unfortunately, most people with clinical depression never seek treatment. Left undiagnosed and untreated, depression can worsen, lasting for years and causing untold suffering, and possibly suicide.