Health Literacy Matters More Than Experience for Advance Care Planning Knowledge Among Older Adults

Abstract

Advance care planning (ACP) engagement is low among vulnerable populations, including those with limited health literacy (LHL). Limited knowledge about ACP may be a modifiable mediator of the relationship between LHL and ACP. Our goal was to determine whether health literacy is associated with ACP knowledge. Cross-sectional. A public health delivery system and Veterans Affairs Medical Center in San Francisco. English- and Spanish-speaking patients (N=1400). ACP knowledge was assessed with seven validated multiple-choice questions. Health literacy was measured using a validated scale. Sociodemographic measures included age, gender, language, education, race, health status, and social support. Prior ACP experience was defined as having documented legal forms and/or goals of care discussions in the medical record. We used Kruskall-Wallis tests and linear regression to examine associations of ACP knowledge with LHL, prior ACP experience, and sociodemographic factors. Mean age of participants was 65 (±10) years, 48% were women, 34% had LHL, 32% were Spanish-speaking, 47% had ≤ high school education, and 70% were non-white. Mean 7-point knowledge scores were lower for those with limited versus adequate health literacy (3.8 (SD 1.9) vs 5.5 (SD 1.7), p<0.001). In multivariable analysis, ACP knowledge scores were 1.0 point lower among those with LHL; 0.6 points lower among Spanish-speakers and ≤ high school education; and 0.5 points lower among individuals of non-white race (p<0.001 for all). Knowledge scores were 0.02 points lower per year of older age (p=0.007) and 0.01 points higher per point of greater social support (p=0.005). Prior ACP experience was not associated with knowledge after adjustment (p=0.7). Health literacy and sociodemographics are stronger predictors than prior ACP experience of ACP knowledge. This study suggests that providing easy-to-understand ACP materials is paramount and should be offered even if patients have previous experience with the ACP process.