Health literacy disparities in Asian populations: Important variation by ethnicity, English proficiency, and US nativity

Low health literacy is an important determinant of health status and access to care that remains generally unexplored in Asian populations. This study quantified low health literacy prevalence in Asian sub-populations, and considered the correlates of low health literacy in Asians. Methods: Data were used from the 4,381 Asian adults completing the 2007 California Health Interview Survey. Low health literacy was defined as self-reporting that written information at the doctor's office is “somewhat” or “very difficult” to understand. Chinese, Filipino, South Asian, Japanese, Korean, Vietnamese, and Other Asian ethnicity were considered. Self-reported limited English proficiency (LEP) and US nativity were controlled, as were age, sex, education, and poverty in multivariate logistic models predicting low health literacy. Results: The sample had diverse Asian sub-groups: 30% Chinese, 25% Filipino, 11% South Asian, 8% Japanese, 9% Korean, 12% Vietnamese, and 6% Other. One in 5 reported LEP, but this varied by subpopulation from 40% Korean (highest) to 2% South Asian (lowest). Only 25% of the sample was born in the US, which also varied by subpopulation from 67% Japanese (highest) to 15% South Asian (lowest). Average age was 43; 53% were female. Overall, 15% of the sample reported low health literacy. Rates varied dramatically by subpopulation (Chi2(6)=188.97;p<.001): 25% Chinese, 7% Filipino, 9% South Asian, 11% Japanese, 19% Korean, 14% Vietnamese, and 15% Other. Among only those with LEP, rates of low health literacy averaged 39% and also varied significantly by subpopulation (Chi2(6)=76.33;p<.001): 53% Chinese, 18% Filipino, 38% South Asian, 34% Japanese, 30% Korean, 25% Vietnamese, and 30% Other. In multivariate models, being Chinese (OR 2.97; 95% CI: 1.65-5.33) or Japanese (OR 2.73; 95% CI: 1.24-6.03) remained significantly associated with higher rates of low health literacy, and Korean was marginally significant (OR: 1.72; p=.09). (Comparison group was Filipino which had the lowest prevalence). Not having LEP (0.28; 95% CI: 0.19-0.41) and being born in the US (0.33; 95% CI: 0.21-0.54) were also significantly negatively associated with low literacy. Conclusions: While 15% of Asians generally and only 9% of English proficient Asians reported low health literacy, very high rates were seen in certain Asian subpopulations, particularly those with LEP. For instance, 1 in 4 Chinese and 1 in 2 LEP Chinese reported low health literacy, representing a critical barrier to effective health communication. Further studies should consider the relationship and impact of low health literacy to health status and access to care in Asian populations.