Limited efficiency with the English language increases the risk of adverse medication reactions

Limited efficiency with the English language is a barrier to medical comprehension and increases the risk of adverse medication reactions, according to a recent study led by researchers at the University of California, San Francisco.

The UCSF study, which appears in the online version of the Journal of General Internal Medicine on August 1, is the first multilingual, population-based study to focus on the impact of English proficiency and physician language on medical comprehension.

"Looking at a broad population of respondents with various native languages, we found English proficiency is an independent risk factor for difficulty in understanding medical situations and reporting problems with medications," said lead author Elisabeth Wilson, MD, MPH, research fellow and clinical instructor of medicine at UCSF.

According to the study, respondents who were limited in their English proficiency were significantly more likely to report problems understanding a medical situation, experience confusion about how to use medication, have trouble understanding labels on medications, and suffer a bad reaction to medication due to problems understanding instructions.

Researchers conducted a telephone survey with 1200 Californians in 11 different languages – Russian, Spanish, Cambodian, Vietnamese, Farsi, Armenian, Chinese (Cantonese and Mandarin), Korean, Tagalog (Philippines) and Mien (Hmong). Of the respondents, 49 percent were defined as being limited English-proficient (LEP). Respondents were defined as LEP if they responded "not well" or "not at all" to the question, "How well do you understand English?" The comprehensive survey included 48 questions ranging from health care access to satisfaction to comprehension.

Data also revealed more than two-thirds (69 percent) of LEP respondents reported that their physicians spoke their native language, yet they were still significantly more likely to report problems understanding a medical situation than English-proficient respondents.

Overall, LEP respondents who had access to a language concordant physician had a much improved understanding of their medical situation. Fifty-seven percent of LEP respondents with a language discordant physician reported comprehension problems compared with only 44 percent of those with language concordant physicians.

"This study highlights the difficulties persons with limited English skills face when navigating the complex U.S. health care system," Wilson said. "Our health care systems should do more to improve cultural and linguistic competence between patient and physician."

In addition to poorer comprehension, LEP respondents were significantly more likely than English proficient respondents to be elderly, female, less educated, uninsured and have lower income. "In past studies, these factors also have shown to increase the risk for health disparities in population groups," added Wilson. "The combination of these factors and limited English proficiency help explain the high prevalence of comprehension problems in this country."