NEW YORK (Reuters Health) - The more educated you are, the less likely you are to become chronically ill or disabled, but the amount of money you make plays a bigger role in whether your illness progresses, a new study shows.

Based on the findings, the most effective single policy strategy for improving health might be to make higher education more accessible, Dr. Pamela Herd of the University of Wisconsin-Madison, the study's lead author, told Reuters Health.

Instead of focusing exclusively on getting people to lose weight and exercise, she explains, "you can do something earlier in the causal chain to improve people's health outcomes," noting that the more educated people are, the more likely they are to exercise, maintain a healthy weight, and eat a healthy diet.

Most studies of socioeconomic status and health have looked at status, and health, as single dimensions, Herd and her colleagues note. To get a better sense of how socioeconomic status affects health, the researchers looked at the separate effects of educational attainment and income in 8,287 men and women who were followed from 1986 to 2000-2001. Rather than evaluate health as a "unitary construct," they looked at the onset of functional limitations and chronic illness, the progression of both, and mortality.

When the researchers adjusted for income, they found that level of education independently determined a person's likelihood of becoming ill or disabled. People who hadn't finished high school were twice as likely as college graduates to develop functional limitations, while high school graduates who hadn't finished college were at 61 percent greater risk of becoming disabled than their college-educated peers. There was a similar relationship between the risk of becoming chronically ill and educational attainment.

"It is clearly not just the economic resources that come from higher educational attainment that drive the postponement of ill health, in some cases until very late in life," Herd and her colleagues write the Journal of Health and Social Behavior.

But level of education didn't play a role in whether people's health would further decline, or in mortality. Instead, the researchers found, income predicted whether people would become chronically ill, whether their illness would progress, and whether they would die during the course of the study. For example, ill or disabled people with incomes below $10,000 a year were nearly three times as likely as those who made $30,000 or more annually to have their health condition worsen.

The findings are "really about the way that poverty has negative ramifications for health," Herd said, noting that poor people may live in worse housing, have a more difficult time obtaining healthy foods, and have a tougher time getting health care. And poverty can increase stress levels, she adds, which in itself can worsen health.

"We already know what people need to do" to be healthier," the researcher said. "What we talk about a lot less is what kind of structural changes need to be made for people's health to improve."

SOURCE: Journal of Health and Social Behavior, September 2007.

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