LETTER TO THE EDITOR
Reply
Tomas Jernberg, MD, PhD,
Bertil Lindahl, MD, PhD,
Agneta Siegbahn, MD, PhD,
Bertil Andren, MD, PhD,
Gunnar Frostfeldt, MD, PhD,
Bo Lagerqvist, MD, PhD,
Mats Stridsberg, MD, PhD,
Per Venge, MD, PhD and
Lars Wallentin, MD, PhD
Department of Medical Sciences, CardiologyUppsala Clinical Research Institute, University Hospital, 751 85 Uppsala, Sweden
(Email: tomas.jernberg{at}medsci.uu.se).
We appreciate the interest by Jarai and colleagues in our recent paper (1). Unfortunately, from the FRISC-II data we cannot answer the questions raised. Further subgrouping of the data makes the groups small and estimates unreliable.
A number of problems arise when trying to define optimal decision limits in patients with non–ST-segment elevation acute coronary syndrome.One problem is that the level of N-terminal pro-brain natriuretic peptide (NT-proBNP) changes over time after presentation. Previous studies have shown that the level of NT-proBNP increases during the first 14 to 48 h after a myocardial infarction (2), and thereby gradually decreases at least for six months (3). Therefore, the timing in relation to the acute event will be important when defining optimal decision limits for NT-proBNP in patients with non–ST-segment elevation acute coronary syndromes.Thus, NT-proBNP levels measured after a median time of 9 h from the last episode of symptoms in the GUSTO-IV trial (4) does not correspond to levels measured after a median time of 39 h in the FRISC-II trial (1).
Another important issue is whether decision limits should be related to gender. It is well known that NT-proBNP levels are higher in women (5). The reason for this gender-related difference is still unclear. The fact that the age-related mortality is lower in women than in men suggests that the reason for this gender difference does not cause increased mortality. Therefore, we believe gender differences should be considered when determining suitable decision limits. Evidently, further studies regarding the best time point for analysis and the most appropriate decision limit are needed.
 |
References
|
|---|
- Jernberg T, Lindahl B, Siegbahn A, et al. N-terminal pro-brain natriuretic peptide in relation to inflammation, myocardial necrosis, and the effect of an invasive strategy in unstable coronary artery disease J Am Coll Cardiol 2003;42:1909-1916.[Abstract/Free Full Text]
- Talwar S, Squire IB, Downie PF, et al. Profile of plasma N-terminal proBNP following acute myocardial infarction; correlation with left ventricular systolic dysfunction Eur Heart J 2000;21:1514-1521.[Abstract/Free Full Text]
- Lindahl B, Johnston N, Jernberg T, Stridsberg M, Venge P, Wallentin L. Cardiac dysfunction in non–ST-elevation ACS is partly reversible: analysis of serial measurement of NT-pro B-type natriuretic peptide (abstr) J Am Coll Cardiol 2004;43(Suppl A):306A.
- James SK, Lindahl B, Siegbahn A, et al. N-terminal pro-brain natriuretic peptide and other risk markers for the separate prediction of mortality and subsequent myocardial infarction in patients with unstable coronary artery disease: a Global Utilization of Strategies To Open occluded arteries (GUSTO)-IV substudy Circulation 2003;108:275-281.[Abstract/Free Full Text]
- Johnston N, Jernberg T, Lindahl B, et al. Biochemical indicators of cardiac and renal function in a healthy elderly population Clin Biochem 2004;37:210-216.[CrossRef][Medline]
|
Top
References