NEW YORK - Worrying about the looming threat of unemployment can be more damaging to a person's health than actually being jobless, according to a U.S. study.

With the United States suffering its worst recession since the depression, researchers set out to look at how job insecurity impacted the health of workers.

This study provides the strongest evidence to date that persistent job insecurity has a negative impact on worker health, said sociologist Sarah Burgard of the University of Michigan Institute of Social Research.

It may seem surprising that chronically high job insecurity is more strongly linked with health declines than actual job loss or unemployment.

Burgard and her colleagues James House and Jennie Brand, of the University of California, Los Angeles, assessed the impact of job insecurity by analyzing data on 1,700 adults and studies conducted between 1986 and 1989 and from 1995 and 2005.

In one group included in the research published in the journal Social Science and Medicine, they found that chronic job insecurity was a stronger predictor of poor health than either smoking or high blood pressure.

UNRELENTING NATURE OF UNCERTAINTY

The researchers questioned people about the likelihood of losing their main job in the next couple of years and the chances of holding on to the position.

They also asked people to rate their overall health and used a scale of depressive symptoms to gauge their mood and psychological health.

The research included people who had lost their jobs and those who had managed to get back into the labor force.

We definitely found that persistent job insecurity had a stronger impact on health decline than those job losses. This is among people who managed to get back in, Burgard told Reuters.

Persistent stress is a strain on people. It is the unrelenting nature of the uncertainty that really gets you.

She added that the long-term nature of job insecurity can raise blood pressure and change levels of stress hormones that over-time can lead to health problems.

Anything that employers can do to provide more information for workers about what is likely to happen is probably a good thing, said Burgard.

One of the most stressful aspects of job loss is losing the benefits that go with it. Unlike many European countries which have nationalized health systems, health coverage in the United States is tied to employment.

I think that is part of the reason we are finding the large effects of persistent insecurity. There are real consequences if you lose your job in the U.S., Burgard explained.

This is one of the big issues that we think make it a particularly salient stressor for people.

She suggested people facing potential unemployment should try to exert as much control as possible and to make a plan. If they have health coverage through their job they should use it while they still can.