- Email: [email protected]
Natriuretic Peptides for Assessing the Prognosis of Acute Pulmonary Embolism
We agree with the comments that the statistical analysis in a sample of 50 control subjects and 125 case patients for 20% minor allele frequency was underpowered. In the statistical analysis, we did not calculate the odds ratio because the p value was > 0.05. We did not calculate the statistical power because the results were all negative and the Fisher exact test was used when a cell value was < 5. The leptin gene has been proposed as a candidate gene for states of energy deficiency, including obesity and OSAS2; however, genetic diversity in different racial populations causes inconsistent results in studies regarding the assockitions of the leptin and LEPR polymorphisms with OSAS.2 In this study, we analyzed the associations of the polymorphisms of leptin and LEPR genes not only with OSAS patients, but also with obese OSAS patients (ie, OSAS patients with a body mass index of 5 27 kp/m2)and the severity of OSAS in a Japanese population. Our results were consistent with previously reported studies4 regarding the association of the leptin gene with obesity in a Japanese population. We believe that the current leptin and LEPR genetic information provides a reference for future replications as well as recommends a method for the specific analysis of obese OSAS patients and the seventy of OSAS. We completely agree that the study should be replicated when enough samples are collected at our institute and the study can be powered appropriately. Masayuki Hanaoka, MD, PhD Keishi Kubo, MD, PhD, FCCP Shinshu University School of Medidne Matsumto, Japan
The authors have reported to the ACCP that no significant conflicts of interest exist with any com aniedorganizationswhose roducts or services ma be discusselin this article. gepmduction of this a r d e is rohibited without written permission from the American Colleee orchest Phvsicians ~www.chestiournal. org/misdre rintsshtml): Corresp(& to: Masa ki H a w k , MD, PhD, First Department of Medidne, Shinsc Unioersity School of Merllcne, 3-1-1 Asahi, Matsumoto 390-8621, lapan; e-mail: [email protected]. shinshu-u.ac DO1 10.13~Wchest.08-0620
REFERENCES 1 Hanaoka M, Yu X, Urushihata K, et al. Leptin and leptin rece tor gene polymorphisms in obstructive sleep apnea synbrlome. Chest 2008; 133:79-85 2 Brennan AM, Mantzoros CS. Drug insight: the role of leptin in human physiology and pathophysiology-emergin clinical applications. Nat Clin Pract Endocrinol Metak 2006; 2:318327 3 Moffett S , Martinson J, Shriver MD, et d. Genetic diversity and evolution of the human leptin locus tetranucleotide repeat. Hum Genet 2002; 110:412417 4 Matsuoka N, Ogawa Y, Hosoda K, et al. Human leptin receptor gene in obese Japanese subjects: evidence against either obesity-causing mutations or association of sequence variants with obesity. Diabetologia 1997; 40:1204-1210
Natriuretic Peptides for Assessing the Prognosis of Acute Pulmonary Embolism To the Editor:
We read with interest the recent article by Samuel Goldhaber in CHEST (February 2008),' who concluded that the www.chestjournal.org
incorporation of cardiac biomarkers such as troponin and the rapid assessment of right ventricular (RV) size into the routine workup of patients with acute puhnonary embolism (APE) would he4 to predict the likelihood of adverse outcomes. We definitely agree with this conclusion, and we would like to make further Ob~rvations.
Elevated levels of natriuretic peptides, especially the N-terminalpm-brain n a t r i h c peptide (NT-proBNP), are frequently observed in the setting of APE, reflecting right heart strain? Their measurement is helpful and highly accurate in idenidjmg low-risk APE patients, displaying a negative preclictive value (NW) for in-hospital death close to 9996.2 Because of the short half-life of natriureticpeptides, particularly NT-proBNP, these biomarkers may also be helpful in serial monitoring and in gauging the success of Merent APE treatment regimens.3 In fact, a treatment-induced drop in wedge pressure in patients with decompensated heart failure due to volume overload is often accompanied by a rapid drop in the levels of natriuretic peptides? Tulmki et alJ recently showed that cardiac tmponin T (cTnT) and NT-proBNP levels measured on hospital admission predicted all-caw mortality and APE-related deaths, whereas RV overload predicted only APE-related mortality. Interestingly, although RV overload showed a N W of 100% for APE-related mortality, its predictive vahe was only 13%.In cuntrast, the positive predictive value of NT-proBNP and cTnT (in micrograms per liter) was 338,without a marked decrease of the N W (97%).s The acknowledged limitations of echocardiography include its restricted availabilityon a 24-h basis every day of the year and the relatively high cost. Although further prospective studies are needed to establish whether a combination of the measurement of cTnT and NT-proBNP levels might provide faster and equally reliable prognostic information as that provided by echocardiography alone, preliminary data indicate that this possibility should be considered. Giuseppe Lippi, MD Ciovanni Targher, MD Universita degli Studi di Verona Verona, Italy
The authors have reported to the ACCP that no significant conflicts of interest exist with any corn aniedorgmizations whose products or services may be discusse in this article. Reproduction of this article is rohibited without written permission h m the American College o Chest Physicians (www.chestjournal. org/misdre xintsshtml). Correqxn&nce to: Gius e Li i, MD, S a h e di Chimica Clinica, Di artimento di genzePRmfologico-Bimdiche, Universitd de& Studi 03 Verona, Ospedale Policlinico C. B. Rossi, Piazzale Scum, 10, 37134 Verona, Italy; e-mail: [email protected] DOI: 10.1378/chest.08-MM
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REFERENCES 1 Goldhaber SZ. Assessing the prognosis of acute pulmonary embolism: tricks of the trade. Chest 2008; 133:334336 2 Kucher N, Goldhaber SZ. Risk stratification of acute pulmonary embolism. Semin Thromb Hemost 2006; 32:838-847 3 Kucher N, Goldhaber SZ. Cardiac biomarkers for risk stratification of patients with acute pulmonary embolism. Circulation 2003; 108:2191-2194 4 Daniels LB, Maisel AS. Natriuretic peptides. J Am Coll Cardiol2007; 502357-2368 5 Tulevski 11, ten Wolde M, van Veldhuisen DJ, et al. Combined utility of brain natriuretic eptide and cardiac troponin T may improve rapid tria e an risk stratification in normotensive patients with pumonary embolism. Int J Cardiol 2007; 116~161-166
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CHEST I 133 16 / JUNE, 2008
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The authors have reported to the ACCP that no significant conflicts of interest exist with any com aniedorganizationswhose roducts or services ma be discusselin this article. gepmduction of this a r d e is rohibited without written permission from the American Colleee orchest Phvsicians ~www.chestiournal. org/misdre rintsshtml): Corresp(& to: Masa ki H a w k , MD, PhD, First Department of Medidne, Shinsc Unioersity School of Merllcne, 3-1-1 Asahi, Matsumoto 390-8621, lapan; e-mail: [email protected]. shinshu-u.ac DO1 10.13~Wchest.08-0620
REFERENCES 1 Hanaoka M, Yu X, Urushihata K, et al. Leptin and leptin rece tor gene polymorphisms in obstructive sleep apnea synbrlome. Chest 2008; 133:79-85 2 Brennan AM, Mantzoros CS. Drug insight: the role of leptin in human physiology and pathophysiology-emergin clinical applications. Nat Clin Pract Endocrinol Metak 2006; 2:318327 3 Moffett S , Martinson J, Shriver MD, et d. Genetic diversity and evolution of the human leptin locus tetranucleotide repeat. Hum Genet 2002; 110:412417 4 Matsuoka N, Ogawa Y, Hosoda K, et al. Human leptin receptor gene in obese Japanese subjects: evidence against either obesity-causing mutations or association of sequence variants with obesity. Diabetologia 1997; 40:1204-1210
Natriuretic Peptides for Assessing the Prognosis of Acute Pulmonary Embolism To the Editor:
We read with interest the recent article by Samuel Goldhaber in CHEST (February 2008),' who concluded that the www.chestjournal.org
incorporation of cardiac biomarkers such as troponin and the rapid assessment of right ventricular (RV) size into the routine workup of patients with acute puhnonary embolism (APE) would he4 to predict the likelihood of adverse outcomes. We definitely agree with this conclusion, and we would like to make further Ob~rvations.
Elevated levels of natriuretic peptides, especially the N-terminalpm-brain n a t r i h c peptide (NT-proBNP), are frequently observed in the setting of APE, reflecting right heart strain? Their measurement is helpful and highly accurate in idenidjmg low-risk APE patients, displaying a negative preclictive value (NW) for in-hospital death close to 9996.2 Because of the short half-life of natriureticpeptides, particularly NT-proBNP, these biomarkers may also be helpful in serial monitoring and in gauging the success of Merent APE treatment regimens.3 In fact, a treatment-induced drop in wedge pressure in patients with decompensated heart failure due to volume overload is often accompanied by a rapid drop in the levels of natriuretic peptides? Tulmki et alJ recently showed that cardiac tmponin T (cTnT) and NT-proBNP levels measured on hospital admission predicted all-caw mortality and APE-related deaths, whereas RV overload predicted only APE-related mortality. Interestingly, although RV overload showed a N W of 100% for APE-related mortality, its predictive vahe was only 13%.In cuntrast, the positive predictive value of NT-proBNP and cTnT (in micrograms per liter) was 338,without a marked decrease of the N W (97%).s The acknowledged limitations of echocardiography include its restricted availabilityon a 24-h basis every day of the year and the relatively high cost. Although further prospective studies are needed to establish whether a combination of the measurement of cTnT and NT-proBNP levels might provide faster and equally reliable prognostic information as that provided by echocardiography alone, preliminary data indicate that this possibility should be considered. Giuseppe Lippi, MD Ciovanni Targher, MD Universita degli Studi di Verona Verona, Italy
The authors have reported to the ACCP that no significant conflicts of interest exist with any corn aniedorgmizations whose products or services may be discusse in this article. Reproduction of this article is rohibited without written permission h m the American College o Chest Physicians (www.chestjournal. org/misdre xintsshtml). Correqxn&nce to: Gius e Li i, MD, S a h e di Chimica Clinica, Di artimento di genzePRmfologico-Bimdiche, Universitd de& Studi 03 Verona, Ospedale Policlinico C. B. Rossi, Piazzale Scum, 10, 37134 Verona, Italy; e-mail: [email protected] DOI: 10.1378/chest.08-MM
B
P
REFERENCES 1 Goldhaber SZ. Assessing the prognosis of acute pulmonary embolism: tricks of the trade. Chest 2008; 133:334336 2 Kucher N, Goldhaber SZ. Risk stratification of acute pulmonary embolism. Semin Thromb Hemost 2006; 32:838-847 3 Kucher N, Goldhaber SZ. Cardiac biomarkers for risk stratification of patients with acute pulmonary embolism. Circulation 2003; 108:2191-2194 4 Daniels LB, Maisel AS. Natriuretic peptides. J Am Coll Cardiol2007; 502357-2368 5 Tulevski 11, ten Wolde M, van Veldhuisen DJ, et al. Combined utility of brain natriuretic eptide and cardiac troponin T may improve rapid tria e an risk stratification in normotensive patients with pumonary embolism. Int J Cardiol 2007; 116~161-166
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CHEST I 133 16 / JUNE, 2008
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