Studies have highlighted the issue that non-significant association was found between admission glucose levels and mortality among patients hospitalized with acute heart failure (AHF), regardless of the presence or absence of diabetes, in contrast to an acute myocardial infarction. However, till date there are no studies that have defined whether a persistent hyperglycemia (PHG) during heart failure (HF) hospitalization had a better predictive value than admission glucose alone.
Addressing this issue, Dr. N Moreno and coworkers performed the present study that identified the association of PHG with mortality or rehospitalization for heart failure (RHF) and established whether this measurement had a prognostic value as opposed to admission hyperglycemia alone.
Study population consisted of 222 patients who were hospitalized with the diagnosis of AHF from January 2005 to December 2008. Mean patient age of enrollees was 74±11.3 years and 54.1% were men. Mean admission glucose was 180 mg/dL; 51.8% of patients were hyperglycemic, 41% had PHG during hospitalization and 36% of patients had recognized diabetes mellitus.
Hyperglycemia at admission was defined as glucose values ≥140 mg/dl, similar to the previously published thresholds and PHG was defined as mean first 72-hour glucose ≥140 mg/dl. RHF or death from all causes was the primary outcome. Multivariable Cox regression models were used to analyze the results in the entire cohort that also included diabetes and non diabetes patients. The primary etiology of heart failure was ischemic heart disease in 52.7% enrollees and the main clinical presentation was decompensated chronic HF in 61.3% enrollees.
All the enrolled patients were followed until October 2011 and the findings form this study showed 37.4% of patients were readmitted for heart failure and 26.1% died.
No significant association was found between persistent hyperglycemia and rehospitalization for heart failure (hazard ratio of 1.07; 95% confidence interval 0.50 to 2.28); similar results were also observed for the association between persistent hyperglycemia and all-cause mortality (hazard ratio 0.81; 95% confidence interval 0.33 to 2.02), after multivariable adjustment.
Similar results were found between patients with and without known diabetes mellitus (for diabetes x glucose interaction, p=0.36 and p=0.38 for RHF and all-cause mortality, respectively).
In conclusion this study demonstrated that there was no significant association between persistent hyperglycemia and mortality or rehospitalization for heart failure in patients hospitalized with acute heart failure, independently of the presence or absence of diabetes. This study supports the idea that the association between hyperglycemia and adverse outcomes observed in AMI cannot be automatically extrapolated to patients hospitalized with other cardiovascular conditions.