Patients with heart failure (HF) and diabetes mellitus often face complex treatment demands, but social factors may influence their outcomes. A prospective multicenter cohort analysis from the National Heart Failure Registry published in Open Heart assessed whether educational attainment modified the association between diabetes and 1-year mortality.

The study included 10,850 consecutively enrolled patients with HF from 53 hospitals across 21 states in India, with a 1-year follow-up for all participants. Multivariable Cox proportional hazards models assessed mortality risk after adjustment for demographic, clinical, and treatment-related variables. Analyses were stratified by education level and included an interaction term between diabetes and education.

At 1 year, cumulative all-cause mortality was 22.1%. Diabetes mellitus was independently associated with 10% higher mortality risk compared with no diabetes (HR 1.10, 95% CI 1.01 to 1.19). Higher educational attainment was independently associated with lower mortality risk.

Compared with individuals without diabetes and low education, those with diabetes and low education had 25% higher mortality risk (HR 1.25, 95% CI 1.08 to 1.44). In contrast, individuals with diabetes and higher education had 22% lower mortality risk (HR 0.78, 95% CI 0.65 to 0.94). A significant interaction between diabetes and education (P for interaction <0.05) suggested that educational attainment modified the association between diabetes and mortality.

These findings suggest lower educational attainment may amplify diabetes-associated mortality risk in HF, highlighting the importance of health literacy and equitable access to care.