The mediating role of health literacy in the relationship between social support and glycemic control among rural patients with diabetes in Western China: a cross-sectional SEM study.

BACKGROUND

Social support and health literacy are important factors associated with glycemic control in patients with diabetes, but the mediating role of health literacy in rural populations remains unclear.

METHODS

We conducted a cross-sectional survey of 2,280 rural patients with diabetes across five regions in Guangxi using the Social Support Scale and Health Literacy Scale. Data were analyzed using Spearman correlation and structural equation modeling (SEM). A covariate-adjusted SEM was further estimated by including age, sex, education level, household income, disease duration, number of complications, BMI, and treatment type.

RESULTS

Among 2,178 valid questionnaires, the mean social support score was 26.70 ± 9.93, the mean health literacy score was 30.47 ± 9.36, and the mean HbA1c level was 8.60 ± 2.18%. Only 22.64% of participants had HbA1c levels below 7.0%, indicating generally poor glycemic control. Spearman correlation analysis showed that both social support and health literacy were significantly negatively correlated with HbA1c level (p < 0.01). The covariate-adjusted SEM showed acceptable to good model fit (CFI = 0.975, TLI = 0.940, RMSEA = 0.043, and SRMR = 0.018). In the adjusted model, social support remained positively associated with health literacy (β = 0.471, p < 0.001), and both social support (β= -0.308, p < 0.001) and health literacy (β= -0.353, p < 0.001) were negatively associated with HbA1c level. Bootstrap analysis indicated a significant indirect effect of social support on HbA1c through health literacy (estimate = -0.037, 95% CI: -0.042 to -0.031), accounting for 35.05% of the total effect.

CONCLUSION

Health literacy plays a significant mediating role in the relationship between social support and HbA1c level among rural patients with diabetes in western China. Strengthening social support and improving health literacy may help improve glycemic control in rural diabetes management.