Does health literacy mediate the relationship between socioeconomic status and health outcomes?

BACKGROUND: Health literacy (HL) has been hypothesized as one of the mediators in the pathway through which socioeconomic status (SES) affects health outcomes. This study explores whether HL mediates the relation between SES and a selection of health(-related) outcomes. METHODS: Data from the participants of the Belgian health interview survey 2018 aged 15 years and over were individually linked with data from the Belgian compulsory health insurance (n = 6878). HL was assessed with the HLS-EU-Q6. Mediation analyses were performed using the SES as independent variables, health(-related) outcomes as dependent variables and HL as mediating variable. RESULTS: People with low SES were less likely to have preventive dental care (PDC), breast cancer screening (BCS), enough physical activity, good nutritional habits, good self-rated health (SRH). In contrast, they were more likely to use antibiotics and antidepressants. A positive correlation was found between HL and PDC, good nutritional habits, physical activity and SRH, but a negative correlation with use of antidepressants. HL partially mediated the association between SES and PDC, use of antidepressants, nutritional habits, physical activity and SRH. In the relationship between these outcomes and education, the mediation effect of HL accounted significantly for 4.4% to 15.4% of the total effect, while it accounted significantly for 4.2% to 12.0% of the total effect in the relationship with income. There was no significant mediating contribution of HL in the pathway by which SES affects influenza vaccination uptake and BCS. CONCLUSIONS: Although the influence of HL in the pathway is limited, the findings suggest that strategies for improving various health(-related) outcomes among low SES groups may benefit from attention to HL. The low percentage mediated for the use of antidepressants might suggest a shared decision between physician and patients. KEY MESSAGES: • HL partially mediates the association between SES and PDC, use of antidepressants, nutritional habits, physical activity and SRH. Improving HL might reduce SES disparities in these areas. • No mediating effects for influenza vaccination uptake and BCS, indicating a possible influence of the universal health coverage in place.