A simple blood test measuring a single heart hormone (N-Terminal pro-B-type natriuretic peptide) may be all that's needed to determine the risk of heart failure in patients older than 65 years. The societal burden of heart failure (HF) in the United States is staggering. In 2006 there were 1.1 million HF hospitalizations and 3.4 million office visits, translating into more than $37 billion in direct and indirect healthcare costs. Most patients with heart failure are older, with likelihood of developing the condition rising steadily as patients age. Despite the large number of patients affected, it is still challenging to predict the onset of heart failure in the elderly based on traditional risk factors such as cholesterol levels, blood pressure and smoking history. For good reason, much of the current research attempts to look for better ways to identify at-risk patients early.
Studies
A new study aimed to assess whether measuring a hormone secreted by the heart (N-Terminal pro-B-type natriuretic peptide or NT-proBNP) can be an effective way to determine the likelihood of developing heart failure in elderly patients. Investigators administered blood tests to measure NT-proBNP levels in nearly 3000 older Canadians initially free of HF, and then followed them for almost 12 years.
They discovered that patients with the highest initial levels of NT-proBNP (greater than 190 pg/ml) had a 2.5 fold increase in risk of death or heart failure during follow-up as opposed to those with the lowest levels. In addition, changes in NT-proBNP over time were also important. Those with initially low levels who had a 25% increase in their NT-proBNP reading after 2-3 years were significantly more likely to experience heart failure or death; while those with initially high levels which declined by more than 25% on repeat testing had a more favorable outcome. The worst combination was a level of over 190 pg/ml which increased by over 25%.
"We found that NT-proBNP levels are effective in predicting the onset of heart failure and death in elderly people," says Dr. Christopher deFilippi of the Division of Cardiology at the University of Maryland.
In an accompanying editorial, co-author Dr. Richard Troughton of the University of Otago in New Zealand, agrees with the study findings.
"Serial blood testing to measure BNP or NT-proBNP levels could provide additional help in predicting the likelihood of developing heart failure," says Troughton. "Early identification of patients at high risk could allow their physician to optimize their treatment in an effort to prevent heart failure."
More studies are needed to solidify this hypothesis, but these findings are certainly a good step in the continuous effort to help identify predictors of heart failure in an aging population.
"Much like the way younger patients monitor cholesterol to determine if life style changes should be implemented to help improve heart health, we hope consistently measuring NT-proBNP levels will prove as useful for elderly patients."
The study results are published in the February 2, 2010 issue of the Journal of the American College of Cardiology.
Sources:
deFilippi RC et al. Dynamic Cardiovascular Risk Assessment in Elderly Patients. Journal of the American College of Cardiology, 2009.
Vascular Surgery and Laser Vein Center
Please contact us at 877.WMC.VEIN or 877.962.8346.