Association between health literacy and chronic diseases in Anhui Province: findings from a province-wide cross-sectional survey of 16,067 individuals

Chronic diseases represent a major global health burden. Health literacy is a modifiable factor in their prevention and control, yet evidence on its association with multimorbidity remains limited. This study investigated the association between health literacy and chronic diseases, focusing on multimorbidity, among residents of Anhui Province, China. A province-wide cross-sectional survey (July-October 2023) included 16,067 residents aged 15–69 years, selected via multistage stratified probability proportional to size (PPS) sampling. Health literacy was assessed using the Chinese Health Literacy Scale (CHLS). Chronic disease status (none, single, multimorbidity) was self-reported. Multivariate logistic regression analysis was employed to examine the association between health literacy and chronic diseases, adjusting for confounders. The overall adequate health literacy rate was 31.90%. Health literacy levels decreased significantly with increasing chronic disease burden: 35.07% (none), 21.13% (single), 11.61% (multimorbidity; Ptrend < 0.001). After adjustment, individuals with multimorbidity had 24% lower odds of adequate health literacy versus those without chronic diseases (aOR = 0.76; 95% CI 0.60–0.96; P = 0.021). Domain-specific analyses revealed significantly reduced odds of adequate basic knowledge and attitudes (aOR = 0.81; 95% CI 0.67–0.97; P = 0.026) and health-related skills literacy (aOR = 0.77; 95% CI 0.63–0.95; P = 0.014) among individuals with multimorbidity. Multimorbidity was also associated with lower health information literacy (aOR = 0.82; 95% CI 0.69–0.97; P = 0.019). This study observed a significant inverse association between health literacy and chronic diseases, particularly multimorbidity. Targeted health literacy improvement interventions focusing on knowledge, skills, and health information access may represent a crucial, cost-effective strategy for chronic disease prevention and control.