Clinical depression, also known as major depression, is an illness that involves the body, mood, and thoughts. Clinical depression affects the way you eat and sleep. It affects the way you feel about yourself and those around you. It even affects your thoughts.

How does untreated clinical depression affect physical health?

There is mounting evidence that clinical depression takes a serious toll on physical health. The most recent studies exploring health and major depression have looked at patients with stroke or coronary artery disease. Results have shown that people with major depression who are recovering from strokes or heart attacks have a more difficult time making health care choices. They also find it more difficult to follow their doctor's instructions and to cope with the challenges their illness presents. Another study found that patients with major depression have a higher risk of death in the first few months after a heart attack.

How is sleep disrupted by untreated depression?

One of the most telling symptoms of clinical depression is a change in sleep patterns. Though the most common problem is insomnia (difficulty getting adequate sleep), people sometimes feel an increased need for sleep and experience excessive energy loss. Lack of sleep can cause some of the same symptoms as depression -- extreme tiredness, loss of energy, and difficulty concentrating or making decisions.

In addition, untreated depression may result in weight gain or loss, feelings of hopelessness and helplessness, and irritability. Treating the depression helps the person get control over all of these depression symptoms.

What are common signs of insomnia with untreated depression?

Common signs of insomnia include:

• Daytime fatigue
• Irritability and difficulty concentrating
• Sleep that never feels like "enough"
• Trouble falling asleep
• Trouble going back to sleep after waking up during the night
• Waking up at all hours of the night
• Waking up before the alarm clock goes off

What are signs of drug and alcohol abuse with untreated depression?

Alcohol and drug abuse are common among people with clinical depression. They’re especially common among teens and among young and middle-age males. It is very important to encourage these people to get help, because they are more likely to attempt suicide.

Signs of drug and alcohol abuse include:

• Inability to maintain personal relationships
• Secretive alcohol use
• Self-pity
• Tremors
• Unexplained memory loss
• Unwillingness to talk about drugs or alcohol

Those who suffer depression and abuse drugs or alcohol may need very specialized treatment.