The utility of routine natriuretic peptide screening and correlation with echocardiographic evidence of Stage B heart failure in a community based diabetic population

Introduction

Heart Failure remains a major threat to patients living with diabetes. The ADA and AHA/ACC guidelines have now proposed NP-based screening in asymptomatic patients with T2DM(10) to help define risk for HF and for the presence pre-clinical HF(10). We investigate its impact in a routine population with T2DM.

Methods

The patient population was drawn from the STOP-HF patient data base (2). From this population we extracted all patients with DM who has a baseline NP and echocardiographic study within 6 months and a follow up NP and corresponding echo at least one year following the baseline.

Results

A total of 650 patients met the inclusion criteria. Echocardiographic evidence of Stage B is present in 190/650 (29.2%) of the study population. Overall baseline echocardiographic evidence of Stage B HF was significantly more common in the elevated BNP group ((82/163 (50.3%) vs 103/474 (21.7%) p < 0.001)) Reduced baseline (EF < 50%) was only seen in 2.1% of patients in the normal BNP group, compared to 7.4% in the elevated group (p= 0.004). In addition, we found a significant difference across all parameters of diastolic dysfunction between the normal and elevated BNP groups.

False negative values occurred in 103/474 (21.7%). False positive occurred in 81/163 (50.3%). Of this group with an elevated NP and normal baseline echocardiograph, 21/81 (25.9%) developed Stage B HF at follow up of 1.8 years. A baseline elevated BNP was likely to predict future abnormal echocardiographic indices of Stage B HF at follow up. Overall we found the optimal cut off threshold for NP screening was 23.3, which has a sensitivity and specificity of 64.2% and 68.1% respectively for echocardiographic evidence of Stage B HF.

Discussion

The data demonstrates a link between elevated NP and Stage B HF and in particular identifies a significantly increased risk of left ventricular systolic dysfunction. Higher concentrations of NT-proBNP are linked to deterioration of doppler- echocardiographic indices of cardiac function in the general population(11), however the same large, real world data is lacking in DM specific populations. Additionally, longitudinal data on how trends in BNP predict echocardiographic evidence of Stage B HF in the community, remains lacking in a DM specific population. We address this gap in evidencein our study.

The study underlines the importance of the ADA position statement(12). In particular our data link NP elevation to the presence of, or risk of developing Stage B HF a group at high risk for developing HF.

Conclusion

We conclude, the strategy advocated by the ADA proves to be very effective in a community population and identifies high-risk individuals who may benefit from a more timely initiation of effective preventative strategies and ongoing doppler- echocardiographic surveillance.For image description, please refer to the figure legend and surrounding text.For image description, please refer to the figure legend and surrounding text.