TUESDAY, Feb. 14, 2006 (HealthDay News) -- Poverty may play a part in lower scores on the exercise stress tests doctors use to gauge heart health, a new study finds.
Researchers looked at data on more than 30,000 Ohio residents whose doctors had them take stress tests because they had symptoms of coronary disease.
After adjusting for such factors as smoking, other medical problems and insurance status, they found a strong correlation between socioeconomic status and poor performance on cardiac stress tests.
And those poor scores may translate into real danger. Strikingly, the people in the lowest 25 percent of socioeconomic status were nearly twice as likely to die in the following 12 years as the 25 percent who were best-off were.
There could be many reasons for the link, the researchers said. "One is that [poorer individuals] live in areas where they have less opportunity to get to recreational facilities," said study co-author Dr. Michael S. Lauer, a professor of medicine at the Cleveland Clinic. "Also, poorer neighborhoods have a higher crime rate, so they are less willing to be out."
The findings appear in the Feb. 15 issue of the Journal of the American Medical Association.
It's been clear for a long time that there's a link between being poor and having a higher risk of cardiovascular disease, Lauer said. "This gives us an understanding of what that link is," he said. "One theory has been that the link is related to physical activity, that people who are less well-off are less well fit. We sought to test that speculation."
Lack of physical fitness is one major risk factor for heart problems, Lauer said, and there are several possible explanations why poverty goes along with poor physical fitness.
Besides a lack of access to fitness facilities, poor diet can also play a role. "There are data showing that people who are less well off have a poor diet, and there is definitely a link between diet and risk," he said.
Wealth seems to act as a kind of buffer against death risk -- even when patients don't do well on a stress test, Lauer added. "We found that those who are physically unfit but relatively well-off have an increase in risk that is not as great as those who are not well-off," he said.
The findings have obvious implications for public policy, according to Lauer. He believes that money spent on recreational facilities in poorer neighborhoods could pay dividends in better health.
There is also a lesson for doctors. When physicians try to assess cardiovascular risk, they currently look at factors such as obesity, smoking, cholesterol level and diabetes as measures of potential problems, Lauer noted.
"They should consider a poor socioeconomic status as a marker of increased risk, like diabetes or smoking," he said. "That is especially true for people who are physically unfit."
For more on heart disease risk factors, head to the American Heart Association.