Hyperglycemia, Chronicity of Diabetes, and Their Relationship With Heart Failure

Increased levels of glycosylated hemoglobin (HbA1c), fluctuations in HbA1c, and a history of severe hypoglycemia are all significant risk factors for heart failure in patients with type 2 diabetes, suggests a study published Sept. 13, 2024 in the journal Diabetes, Obesity and Metabolism.

This study from Australia systematically reviewed longitudinal studies investigating the association of glycemic risk factors such as glycosylated hemoglobin (HbA1c), HbA1c variability, hypoglycemia, and diabetes duration with HF in patients with type 2 diabetes. The objective was to explore the link between these factors and the risk of HF in these patients.

The final analysis included 40 studies involving 4,102,589 participants. Analysis showed a 15% increased risk of heart failure for each 1% increase in HbA1c, a 2% increased risk for each additional year of diabetes and a 43% increased risk for individuals with a history of severe hypoglycaemia. A 20%-26% increased risk of HF was observed for each unit increase in the metrics of HbA1c variability (HbA1c standard deviation, coefficient of variation, and average successive variability). All included studies scored high in the risk of bias assessment indicating that issues such as selection bias, confounding factors, and reporting bias might have influenced the results. Results from Egger’s test showed the presence of publication bias suggesting that studies reporting strong associations between HbA1c levels and heart failure risk were more likely to be published, while those with negative or weaker findings might have been underreported or not reported. After adjusting for publication bias, a 14% increased risk of HF per percentage point increase in HbA1c was observed on trim-and-fill analyses.

This study has highlighted the contribution of glycemic risk factors and duration of diabetes to the increased risk of HF in patients with type 2 diabetes. Early intervention and proactive management of these risk factors to achieve stable glycemic levels, reducing HbA1c variability and avoiding severe hypoglycemic episodes may minimize the risk and improve patient outcomes.

Reference

1. Mahtab Tabesh, et al. The association of glycaemic risk factors and diabetes duration with risk of heart failure in people with type 2 diabetes: A systematic review and meta-analysis. Diabetes Obes Metab. 2024 Sep 13. doi: 10.1111/dom.15938.