The Impact of Changes in Fasting Plasma Glucose before and after Heart Failure Diagnosis on All-Cause Mortality

INTRODUCTION: Fasting plasma glucose (FPG) fluctuations are increasingly recognized as potential prognostic markers in cardiovascular diseases. However, the association between changes in FPG before and after heart failure (HF) diagnosis and long-term mortality remains unclear. This study aimed to evaluate the impact of FPG changes surrounding HF diagnosis on all-cause mortality to inform individualized HF management strategies. METHODS: This prospective cohort study was conducted using data from the Kailuan study. A total of 3,533 patients newly diagnosed with HF were included after excluding individuals with a history of HF, malignancies, or missing FPG data. FPG levels measured before and after HF diagnosis were used to classify participants into five groups: significant decrease (Q1), mild decrease (Q2), stable (Q3), mild increase (Q4), and significant increase (Q5). The primary outcome was all-cause mortality, with follow-up through December 31, 2021. Survival outcomes were evaluated using Kaplan-Meier curves and multivariate Cox regression models. RESULTS: During a mean follow-up of 5.63 ± 3.80 years, 1,446 all-cause deaths were recorded. Kaplan-Meier analysis demonstrated a significantly higher mortality risk associated with greater changes in FPG levels (log-rank p < 0.0001). In multivariable Cox models, both the Q1 (significant decrease) and Q5 (significant increase) groups exhibited elevated mortality risks compared to the Q3 (stable) group, with adjusted hazard ratios of 1.37 (95% CI: 1.12-1.67) and 1.35 (95% CI: 1.12-1.62), respectively. CONCLUSION: Significant changes in FPG before and after HF diagnosis are independently associated with increased all-cause mortality. These findings highlight the importance of maintaining glycemic stability and support the need for personalized glucose management strategies in patients with HF.