Long-Term Glycemic Variability Predicts Adverse Outcomes in Diabetic Heart Failure With Preserved Ejection Fraction

Previous studies have shown associations between glycemic variability (GV) and cardiovascular outcomes in patients with type 2 diabetes. However, the effect of GV on outcomes in diabetic patients with heart failure with preserved ejection fraction (HFpEF) has not been investigated.

To investigate the association between increased GV and cardiovascular outcomes in diabetic patients with HFpEF.

Between 2014 and 2019, we conducted a retrospective cohort analysis using the electronic medical records of a tertiary medical center in Taiwan. Diabetic patients with HFpEF were enrolled. Each individual's coefficient of variability of fasting glucose (FGCV) was determined and the FGCVs were categorized into tertiles. Multivariable Cox regression models and the Kaplan-Meier with log-rank test were used to assess the association between the FGCV and the risk of hospitalization for heart failure (HHF), atrial fibrillation (AF), cardiovascular mortality, and overall mortality.

In a cohort comprising 74 835 individuals diagnosed with diabetes, a subset of 753 patients was identified with HFpEF and measurement of FGCV. The median follow-up duration was 38.1 months. In the model of full adjustment, the third FGCV tertile was statistically significantly associated with an increased risk of HHF compared to the first tertile (hazard ratio [HR] = 1.32; 95% CI, 1.04-1.69; P = .025). Likewise, the highest FGCV tertile was associated with an increased risk of death (HR 1.65; 95% CI, 1.16-2.35; P = .005), whereas it was not associated with increased of AF and cardiovascular mortality. Kaplan-Meier analyses revealed a statistically significant association between FGCV and both HHF and overall mortality (log-rank P = .022 and <.001, respectively).

Our study highlights a significant association between increased GV and a higher incidence of HHF as well as an elevated overall mortality rate in individuals with diabetes and HFpEF.