Facts about Clinical Depression

Depressed mood is a normal consequence of any disturbing event in life ranging in effect from losing a chess game to the death of a loved one. Such depression heals naturally without any treatment in some time, say from a few days to a few months. If the depression persists for as long as six month, or more, it is called clinic depression and needs professional treatment.

Types of Clinical Depression

There are three main types of clinical depression: unipolar, bipolar, and dysthymia. Unipolar depressive disorder is also called major depression. The patient suffers episodes of severe depression with no signs of a light mood for months. Bipolar depressive disorder is also called manic-depressive disorder. In these cases, patients experience severe depression alternating with episodes of mania (intensely happy mood). Dysthymia is the mild form of depression characterized by long periods of sadness and pessimism.

Symptoms of Clinical Depression

Whether of any type, depression has some common symptoms experienced by all patients. These include persistent feelings of sadness, worthlessness, and hopelessness; high degree of irritability and overreaction to irritable situations; lack of motivation toward life activities; failure in concentrating and poor memory; feeling of fatigue and restlessness; low self-esteem and guilt feelings; sleep disturbances; slow movements, thinking, and/or speech; asocial and antisocial behavior; suicidal thoughts or behavior; and reporting physical pain/ache without any signs of a physical cause.

Prevalence of Depression

Clinical depression prevails among an estimated 12 per cent of population. It is reported in all ages, races, and both genders. However, bipolar disorder is more common among women than among men.

Causes of Clinical Depression

There is no single cause or single type of causes responsible for depression. Each case of depression appears to be the result of a unique combination of physiological and environmental factors.

A major known physiological cause of depression is the insufficient quantity or inactivity of the neurotransmitter serotonin. Another neurotransmitter, norepinephrine, also plays an important part in relieving depression. Evidence reveals that depression can be inherited. Magnetic Resonance Imaging studies show the difference in the brain function of depressed people as opposed to normal people. The subgenual prefrontal cortex of brain has been found smaller in pateints having a family history of depression. Addiction to drugs and alcohol is also held responsible for depression. And all these causes are significantly influenced by social/environmental factors like painful childhood experiences, traumas, and one's belief system etc.

It should be noted that depression is sometimes an indicator of another disease like heart disease, cancer, or disruption of thyroid function. To properly diagnose the condition, one must consult a physician for relevant tests.