In a study involving 3,260 people age 65 and older, researchers found that those who can't read well enough to understand basic health care information were more likely to die within 6 years than those who can. Twenty-five percent of those studied were considered to have "inadequate" health literacy as determined by their ability to read and understand prescription labels, appointment slips, and basic instructions about how to prepare for an X-ray.
During the study period, 40% of those with "inadequate" literacy and 29% of those with "marginal" literacy died. In contrast, only 19% of those whose literacy was deemed "adequate" died.
After controlling for health status at the start of the study and other variables, researchers concluded that patients whose health literacy is inadequate are 50% more likely to die than patients who can understand health care material. They say that reading fluency independently predicted mortality and cardiovascular death among older adults living in the community.
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