Abstract 12587: Glycaemic Control and the Development of Heart Failure in Diabetic Patients with Left Ventricular Systolic Dysfunction on Echocardiography.
Background: There is controversy regarding the importance of glycaemic control in patients with type 2 diabetes mellitus (T2DM) and chronic heart failure (CHF) . Recent evidence suggests that tight glycaemic control may be associated with worse survival. The aim of this study was to examine the relationship between HBA1c and the risk of incident CHF and to examine the relationship between HbA1c and outcome in T2DM with established CHF.
Methods: This study was carried out in the population (∼ 400000) of Tayside, Scotland, using data from the Go-DARTS study, the echocardiography dataset (∼ 120000 scans) and the dispensed prescribing database maintained by the Health Informatics Centre (HIC) of the University of Dundee. The incidence date of new CHF was determined during the study period (Jan 1991 to June 2008). CHF was defined as impaired left ventricular systolic function on echocardiography together with prescription of loop diuretic and / or the presence of a hospital discharge code for CHF. A prospective case control study was performed with each case of CHF matched with up to 5 controls for gender and age at date of diagnosis with diabetes. Development of CHF was modeled using conditional logistic regression using mean HBA1c during the study period, number of HbA1c measures, standard deviation and thiazolidinediones prescribing as covariates. Subsequently a proportional hazards model was used to consider the impact of HbA1c on survival of the cases.
Results: Out of 9172 diabetic individuals there were 1135 incident cases of CHF (mean age at diagnosis 60.3±13.8 yrs, 61.9%; males). The adjusted HR of developing CHF for each 1%; increase in HbA1c was 1.31 (95%; CI 1.20,1.44) p=1.43x10-9. In the cases there were 726 deaths. Death occurred in 38%; of patients in Q1 (HBA1c ≤6.5%;), 28%; in Q2 (6.5<HBA1c≤7.2), 34%; in Q3 (7.2<HBA1c≤7.9 ), 36%; in Q4 (7.9<HBA1c<8.6) and 38%; in Q5 (HBA1c<183>8.6). Using Q1 as the reference group, Q4 and Q5 had increased mortality (risk adjusted HR 1.287 (95%; CI 1.0.980 – 1.690, p=0.07) and HR 1.628 (95%; CI 1.216 – 2.179, p=0.001) respectively.
Conclusions: These data suggest that glycaemic control is an independent risk factor for incident CHF in persons with T2DM. In diabetic patients with established CHF, a tight glycaemic control is associated with a better outcome.
- © 2010 by American Heart Association, Inc.