Mild Depression Can Damage Immune System

Mild Depression Can Damage Immune System

THURSDAY, Oct. 16 (HealthDayNews) -- Even a bout of mild depression can throw off a person's immune system, a change that can set up older adults for development of serious age-related diseases.

That's what Ohio State University researchers found. Their report appears in the current issue of the Archives of General Psychiatry.

The study shows the impact a person's mental health can have on their physical health and provides a picture of the body's response to mild depression.

The researchers studied 47 people who were either current or former caregivers taking care of spouses with Alzheimer's disease or some other form of dementia. They were matched with a control group of people who weren't caregivers.

Blood samples were collected from people in both groups just before they received their annual influenza vaccination and again two weeks after their vaccination. The study participants also completed a form designed to gauge their level of depression.

The survey revealed the current and present caregivers had modest levels of depression but were not clinically depressed.

When their blood samples were analyzed, the depressed caregivers' levels of the immune system component Interleukin-6 (IL-6) were 30 percent higher two weeks after they received their influenza vaccination. IL-6 levels in the control group were essentially unchanged.

The increase in IL-6 levels in the depressed caregivers after vaccination was unexpected and important, researcher Ronald Glaser, professor of molecular virology, immunology and genetics, says in a prepared statement.

It suggests low levels of depression are associated with an increased IL-6 response to an antigen, Glaser says.

Sustained higher-than-normal levels of IL-6 have been linked to long-term inflammation which, in turn, is implicated in a number of age-related health problems such as diabetes, cardiovascular disease, osteoporosis, arthritis, cancers, Alzheimer's and periodontal disease.

Here's where you can learn more about the immune system