52 Brain natriuretic peptide predicts all cause mortality in patients with type 2 diabetes and normal ejection fractions
Introduction The use of brain naturetic peptide (BNP) to predict outcome in patients with normal ejection fractions (EF) and type 2 diabetes (T2DM) is understudied. Only three previous studies have specifically addressed the question as to whether BNP adds prognostic information in T2DM. There appears to be a link between survival and BNP in T2DM, however these studies included small numbers of patients and did not fully exclude left ventricular systolic dysfunction (LVSD). We therefore studied the 5-year survival in a cohort of 500 T2DM patients prospectively phenotyped with echocardiography.
Methods 500 patients with T2DM where studied with echocardiography between April 2002 and October 2003. Patients were recruited from the diabetes clinics at Ninewells Hospital, Dundee. Transthoracic echocardiography was performed by one trained operator and left ventricular (LV) assessment was performed using modified biplane Simpson's method over three cycles. We excluded individuals with EF of <55%. Follow-up data was linked via the Health Informatics Centre (HIC), to mortality data, laboratory test data, hospitalisation, and prescribing via the community health index (CHI) number. Cox proportional hazards model was used to examine the effects of BNP (bedside stick measurement) measure on all-cause mortality using age, sex, smoking status, hypertension, IHD, duration of diabetes, and diabetic drug prescription as co-variants. Outcome was all cause mortality.
Results In total we followed 316 patients over 8 years. 56 patients died over this time. After adjusting for confounding factors we have shown that for every 10-unit increase in BNP there is a 6% increased risk of death. HR 1.06 (95% CI 1.02 to 1.10) (p=<0.01).
Conclusions In patients with normal EF, BNP is an independent predictor of death in a cohort of T2DM patients. Although more research is needed, BNP may become an important tool in risk stratifying T2DM patients in the future.