Fasting blood glucose at admission and survival in patients with dilated cardiomyopathy: a single-center cohort study

Abstract

Background: Recent data have suggested that impaired fasting glucose (IFG) is an independent risk factor for mortality in patients with heart failure. However, the prognostic indicator of elevated fasting blood glucose (FBG) such as IFG in dilated cardiomyopathy (DCM) was not well understood. The purpose of this study was to examine the association between IFG at admission and survival in hospitalized patients with DCM.

Methods: A retrospective cohort study was undertaken in 1 089 hospitalized patients with DCM in Fuwai Hospital from November 2003 to September 2 011 (female 26.5%, 51.4±14.6 years old). Standard demographics, echocardiography and routine blood samples were obtained shortly after admission. The outcomes were assessed using all-cause mortality at a mean follow-up of 3.5±2.3 years and were analyzed using Kaplan-Meier survival curve (log-rank test) and Cox regression.

Results: The cohort consisted of 1 089 patients with DCM, 835 patients with normal fasting glucose (NFG, FBG<6.1 mmol/L, 76.7%), 113 patients with IFG (FBG 6.1-6.9 mmol/L, 10.4%), and 141 patients with FBG≥7.0 mmol/L (12.9%). Among the 1 089 patients studied, 252 (23.1%) died over a mean follow-up period of 3.5±2.3 years. All-cause mortality rates were highest in patients with FBG≥7.0 mmol/L (31.2%), intermediate in those with IFG (24.8%), and lowest in those with NFG (21.6%); a significant difference in all-cause mortality rate was found among the 3 groups (log-rank χ(2)=6.715, P=0.035). After adjustment for baseline variables, New York Heart Association (NYHA) functional class, QRS duration, left atrium diameter, systolic blood pressure, FBG≥7.0 mmol/L, not IFG, and circulating creatinine levels were the variables that remained as predictors of all-cause mortality.

Conclusion: In the present study, all-cause mortality was higher in patients with FBG≥7.0 mmol/L compared to the patients with NFG, and FBG≥ 7.0 mmol/L, not IFG, was one of predictors of all-cause mortality in DCM patients.