Adherence to HIV therapy linked to health literacy

NEW YORK (Reuters Health) - HIV infected patients with low literacy levels often don't understand the medication instructions offered by healthcare providers and are therefore much less likely to be compliant with treatment, study findings suggest.

The findings also indicate that African Americans with HIV infection are more than twice as likely to be nonadherent compared with their white counterparts. However, when the data were analyzed, lead investigator Dr. Chandra Y. Osborn, at Northwestern University, Chicago, and colleagues found that health literacy mediated the racial disparities.

The level of health literacy was determined by the subjects' overall literacy skills, the researchers explain. Past studies have shown that low health literacy is associated with poor health outcomes and is more common among African Americans than whites.

Osborn's group investigated the association between health literacy and racial differences in medication adherence over time among 204 HIV-infected patients attending outpatient clinics in Chicago and Shreveport, Louisiana. The patients, 80 percent male and 45 percent African American, were 40 years of age, on average.

Overall, more than 70 percent of the study participants were taking three or more HIV medications and more than half were being treated for other chronic illnesses, the investigators report in the American Journal of Preventive Medicine.

A health-related word recognition test identified 68.6 percent of the patients with adequate health literacy (reading at a ninth grade or higher level). Slightly more than 20 percent of the participants had marginal health literacy (7th to 8th grade reading level) and about 11 percent had low health literacy.

The researchers found that the African Americans were 2.4 times more likely to be non-adherent to their medication regimens compared with non-African Americans when the analysis factored in the effects of age, gender, income, number of medications, and non-HIV comorbidities, Osborn said.

Osborn told Reuters Health that when the effects of literacy were considered, "literacy was a significant predictor of non-adherence, such that patients with low literacy were 2.1 times more likely to be non-adherent to their medication regimen than patients with adequate literacy."

Limited health literacy is a potentially modifiable barrier to medication adherence, the investigators note. Those at risk for medication non-adherence may benefit from culturally relevant health education materials and medication labeling written for all literacy levels.

SOURCE: American Journal of Preventive Medicine, November 2007