(Reuters Health) - People who have trouble reading and understanding health information may also be worse off when it comes to their actual health, a new research review finds.

The study, reported in the Annals of Internal Medicine, reviewed past research on people's health literacy.
The term refers to a person's ability to read and understand information about a health condition or to deal with health-related numbers. Someone with diabetes, for example, has to regularly deal with various numbers -- from tracking blood sugar levels to counting carbohydrates.
"I think there's a lot of research attention now being focused on how well people understand the health information they're given," said Nancy D. Berkman, a researcher at RTI International, a non-profit institute based in Research Triangle Park, North Carolina.

And, probably not surprisingly, studies are showing that a poor understanding of health information may translate into poorer health.
In its research review, Berkman's team found that across 96 studies, people with low health literacy -- usually measured with short tests of reading and number skills -- tended to be hospitalized more often than people with greater literacy.
They also had more visits to the emergency room and were less likely to get certain preventive services -- including flu shots and mammograms to detect breast cancer.

Many factors go along with health literacy. Older adults tend to have greater difficulty with the jargon and numbers than younger people do. The same is true for less-educated people versus those with more education.
But Berkman said that even when studies control for those factors, there is still a link between health literacy, itself, and poorer health.
Among elderly people, the evidence suggests that those with low health literacy have generally poorer health and die sooner.
In one study Berkman's team examined, nearly 3,300 older U.S. adults were followed for about seven years. Of those with poor health literacy, 38 percent died during the study period, compared with 19 percent of those with "adequate" literacy.
Even when the researchers accounted for income, education, race and medical conditions at the study's start, poor literacy remained linked to a higher death risk.

Neither that study, nor any single study in the review, prove that low health literacy, itself, is the culprit.
But overall, the review supports the idea that health literacy matters, according to an editorial published with the report.
The study "reinforces the conventional wisdom that improving health literacy will help to improve outcomes," write Cynthia Baur, of the U.S. Centers for Disease Control and Prevention, and Nancy Ostrove, of the U.S. Food and Drug Administration.
Berkman said that researchers are studying a number of ways to address the problem -- from the "big-picture" issues, like making written health information more consumer-friendly, to helping doctors improve their communication with patients.

Last year, the U.S. Department of Health launched the "National Action Plan to Improve Health Literacy." It said one goal is to work with industry and other groups to cut jargon from patient handouts, medical forms, official health recommendations and health Web sites, among other places.
Other aims were to improve doctor-patient communication and support local communities in starting health education programs.
People can also take steps to help themselves, Berkman said. If you don't understand something your doctor tells you or gives you to read, she said, don't assume you are the problem.

"Don't be afraid to ask questions about your medical condition, or about something you've read," Berkman said.
Bringing your spouse or other family member to your doctor visit can also be a good idea, she noted -- especially if you have a complicated medical condition, or multiple health problems.