Abstract
BACKGROUND: 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. DESIGN: Cross-sectional design. SETTING: A public health delivery system and Veterans Affairs Medical Center in San Francisco, CA. PARTICIPANTS: English- and Spanish-speaking patients (N = 1400). MEASUREMENTS: ACP knowledge was assessed with seven validated multiple-choice questions. Health literacy was measured using a validated scale. Sociodemographic measures included age, sex, 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 Kruskal-Wallis tests and linear regression to examine associations of ACP knowledge with LHL, prior ACP experience, and sociodemographic factors. RESULTS: Mean age of participants was 65 (±10) years, 48% were women, 34% had LHL, 32% were Spanish speaking, 47% had high school education or less, and 70% were nonwhite. Mean 7-point knowledge scores were lower for those with limited vs adequate health literacy (3.8 [SD = 1.9 vs 5.5 (SD = 1.7); P < .001). In multivariable analysis, ACP knowledge scores were 1.0 point lower among those with LHL; 0.6 points lower among Spanish speakers and those with high school education or less; and 0.5 points lower among individuals of nonwhite race (P < .001 for all). Knowledge scores were 0.02 points lower per year of older age (P = .007) and 0.01 points higher per point of greater social support (P = .005). Prior ACP experience was not associated with knowledge after adjustment (P = .7). CONCLUSIONS: 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. J Am Geriatr Soc 67:2151-2156, 2019.