He kept it from family members, friends and employers. Some of Walter Washington's children still don't know their father struggles to read and write.
But his doctors knew. The 64-year-old Dallas man told them because he didn't want to risk taking the wrong dose of his diabetes or blood pressure medications.
"I had common sense and mother wit," said Washington, who also has congestive heart failure and an enlarged heart. "I survived."
Washington is among 30 million American adults who can't read instructions on a pill bottle, properly fill out a deposit slip or complete other tasks using basic reading and writing skills, according to the National Center for Education Statistics. The negative health consequences of low literacy are wide ranging, experts say.
Dr. Elizabeth Jacobs, a general internist and health disparities professor at Dell Medical School at the University of Texas at Austin, said it was critical for doctors to learn more about patients' literacy and to help those who struggle.
"Slow down. Don't use medical jargon. Show or draw pictures," Jacobs advises.
Studies dating back at least three decades suggest literacy may be linked to heart disease, stroke and their risk factors.
For example, one study showed adults with low literacy levels had a higher risk of hospitalization for heart failure. Another study found lower reading scores among adults were linked to heart disease and diabetes.
Literacy problems can make it difficult to understand the nature of chronic conditions, keep up with doctor appointments or take medication correctly, experts said.
Many health materials are written above the reading skills of a high school graduate, studies show. Studies published in the past decade suggest health education programs designed for people with poor reading skills help improve self-care habits.
"I don't think people [who can read] can relate to what that means in their everyday lives," said Pam Wall, the executive director of The Literacy Center in Hilton Head, South Carolina, a nonprofit offering basic reading classes.
Many adults with literacy problems grew up in households where there were few resources to make education a priority, Wall said. Others have dealt with dyslexia diagnosed late in life, making it hard to go grocery shopping, apply for jobs or fill out forms at a doctor's office, she said.
The most effective way policymakers can lower the number of illiterate Americans is to increase funding for K-12 education, said Susan Neuman, an early literacy expert at New York University in Manhattan.
Neuman, U.S. assistant secretary of elementary and secondary education between 2001 and 2003, cautioned that "getting a high school diploma is certainly not evidence that [the students] are good readers." But other social factors are usually the underlying reasons, she said.
As for Washington, he continues to take basic reading classes at an adult learning center.
He said he was motivated to learn after he was made deacon of his church, and now he's relying less on his wife to keep up with his medications.
Washington said doctors should always take the time to ask patients whether they can read. He also encourages others who can't read, including his younger sister, to seek help to learn.
"I know more now than I ever have," he said.
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