Insulin use increases mortality risk in diabetic patients with heart failure: Study

Korea: In a study conducted by Se Yong Jang and his team, it was found that insulin treatment is associated with greater mortality risk in heart failure patients with diabetes mellitus than oral hypoglycemic agents (OHAs). The risk was not dependent on the patients' LVEF and HF etiology.

Insulin therapy was found to be associated with increased mortality compared to OHAs. The insulin therapy was harmful especially in patients with low HbA1c levels which may suggest the necessity of specific management strategies and blood sugar targets when using insulin in patients with HF.

According to the study, insulin treatment is detrimental, particularly in individuals with low HbA1c levels or more severe types of heart failure. The finding of this study was published in the Cardiovascular Diabetology journal on 8th September 2021.

Diabetes mellitus (DM) patients have a greater prevalence of HF than those who do not have it. Approximately 40% of HF patients have diabetes, and they have inferior outcomes than those who do not have diabetes. The purpose of this study was to assess the effect of insulin treatment on mortality in individuals with acute heart failure.

This study included 1740 diabetic individuals from the Korean Acute Heart Failure registry. To equalize the clinical features (pre-treatment variables) across the groups, the risk of all-cause mortality was evaluated using Cox proportional hazard models with inverse probability of treatment weighting.

Key Findings:

 This study discovered that insulin treatment was linked with higher mortality in HF patients with DM, and this was true independent of LVEF or cause of the HF (ischemic or non-ischemic).

 This increase in mortality was seen mostly in individuals with adequate glycemic control or severe degrees of HF as determined by the NYHA class and natriuretic peptide levels.

 Insulin's negative prognostic impact exhibited a comparable trend in both the insulin-only and all-insulin groups, indicating that the effect may be attributable to insulin alone, rather than the combination of insulin and other OHA.

 Among our investigations, the negative effect of increased mortality linked with insulin treatment was most prevalent in individuals with low HbA1c levels (7.0 percent).

In conclusion, due to the negative impact of insulin therapy on patients with DM, specialized management techniques and blood sugar goals may be required when administering insulin in HF patients.

Reference:

Jang, S.Y., Jang, J., Yang, D.H. et al. Impact of insulin therapy on the mortality of acute heart failure patients with diabetes mellitus. Cardiovascular Diabetology 20, 180 (2021). https://doi.org/10.1186/s12933-021-01370-y