LETTER TO THE EDITOR
Heart, Lung and Circulation (2015) 24, 940 1443-9506/04/$36.00 http://dx.doi.org/10.1016/j.hlc.2015.03.022
Frailty Plays a Key Role after Cardiac Surgery We have read with great interest and admiration the article by Crudeli E et al. [1] on the influence of age as a prognostic factor in patients with acute coronary syndrome (ACS) undergoing cardiac surgery. They suggest that age is not an independent predictor of short-term mortality after cardiac surgery in patients with ACS. This finding contradicts some rigorous risk prediction systems as EuroSCORE II [2]. However, we think that there are two reasons that could explain these findings. First, to evaluate the association between an outcome (30-day mortality) and a potential predictor (age) a multivariate analysis must be performed introducing all the variables potentially associated with both (the outcome and the predictor) such as arterial hypertension, diabetes mellitus, left ventricular ejection fraction etc. This is the only way to control all confounding factors in observational studies and be able to draw conclusions [3]. So, the purpose of a univariate analysis is only descriptive. Crudeli et al. [1] only performed a univariate analysis and then, variable ‘‘age’’ was only controlled for one confounding factor, in this case ‘‘admission diagnosis’’ in a bivariate logistic model. Second, ‘‘biological age’’, more than ‘‘chronological age’’, has become a high-priority theme in cardiovascular medicine. Frailty, from the French freˆle meaning of little resistance, is a biological syndrome that reflects a state of decreased physiological reserve and vulnerability to stressors. After a big iatrogenic stressor, such as as cardiac surgery, frail patients are at high risk for decompensation, adverse events, procedural complications, and mortality [4]. These authors [1] only took into account the ‘‘chronological age’’ but not the more important ‘‘biological age’’. Underestimating the importance of frailty may lead us to consider that ‘‘biological age’’ is not a prognostic factor of mortality and complications after cardiac surgery.
Rocio Diaz, MD a,* Daniel Hernandez-Vaquero, MD, PhD a Ruben Alvarez, MD a Cesar Moris, MD, PhD b Jacobo Silva, MD, PhD a a Cardiac Surgery Department, Central University Hospital of Asturias, Asturias, Spain b Department of Cardiology, Central University Hospital of Asturias, Asturias, Spain * Corresponding author at: Cardiac Surgery Department, Hospital Universitario Central de Asturias, Avenida del Hospital Universitario Central de Asturias, 33011, Oviedo, Espan˜a, 985108000. EXT: 36262 Email: [email protected] (R. Diaz). Received 22 March 2015; accepted 25 March 2015; online published-ahead-of-print 17 April 2015
References [1] Crudeli E, Lazzeri C, Stefa`no P, Chiostri M, Blanzola C, Rossi A, et al. Age as a Prognostic Factor in Patients with Acute Coronary Syndrome undergoing Urgent/Emergency Cardiac Surgery. Heart Lung Circ 2015;(Feb 20). pii: S1443-9506(15)00081-5. http://dx.doi.org/10.1016/j.hlc.2015.02.007. [Epub ahead of print]. [2] Nashef SA, Roques F, Sharples LD, Nilsson J, Smith C, Goldstone AR, et al. EuroSCORE II. Eur J Cardiothorac Surg 2012;41:734–44. [3] D’Ascenzo F, Cavallero E, Biondi-Zoccai G, Moretti C, Omede` P, Bollati M, et al. Use and misuse of multivariable approaches in interventional cardiology studies on drug-eluting stents: a systematic review. J Interv Cardiol 2012;25:611–21. [4] Afilalo J, Alexander KP, Mack MJ, Maurer MS, Green P, Allen LA, et al. Frailty assessment in the cardiovascular care of older adults. J Am Coll Cardiol 2014;63:747–62.
© 2015 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier Inc. All rights reserved.
Heart, Lung and Circulation (2015) 24, 940 1443-9506/04/$36.00 http://dx.doi.org/10.1016/j.hlc.2015.03.022
Frailty Plays a Key Role after Cardiac Surgery We have read with great interest and admiration the article by Crudeli E et al. [1] on the influence of age as a prognostic factor in patients with acute coronary syndrome (ACS) undergoing cardiac surgery. They suggest that age is not an independent predictor of short-term mortality after cardiac surgery in patients with ACS. This finding contradicts some rigorous risk prediction systems as EuroSCORE II [2]. However, we think that there are two reasons that could explain these findings. First, to evaluate the association between an outcome (30-day mortality) and a potential predictor (age) a multivariate analysis must be performed introducing all the variables potentially associated with both (the outcome and the predictor) such as arterial hypertension, diabetes mellitus, left ventricular ejection fraction etc. This is the only way to control all confounding factors in observational studies and be able to draw conclusions [3]. So, the purpose of a univariate analysis is only descriptive. Crudeli et al. [1] only performed a univariate analysis and then, variable ‘‘age’’ was only controlled for one confounding factor, in this case ‘‘admission diagnosis’’ in a bivariate logistic model. Second, ‘‘biological age’’, more than ‘‘chronological age’’, has become a high-priority theme in cardiovascular medicine. Frailty, from the French freˆle meaning of little resistance, is a biological syndrome that reflects a state of decreased physiological reserve and vulnerability to stressors. After a big iatrogenic stressor, such as as cardiac surgery, frail patients are at high risk for decompensation, adverse events, procedural complications, and mortality [4]. These authors [1] only took into account the ‘‘chronological age’’ but not the more important ‘‘biological age’’. Underestimating the importance of frailty may lead us to consider that ‘‘biological age’’ is not a prognostic factor of mortality and complications after cardiac surgery.
Rocio Diaz, MD a,* Daniel Hernandez-Vaquero, MD, PhD a Ruben Alvarez, MD a Cesar Moris, MD, PhD b Jacobo Silva, MD, PhD a a Cardiac Surgery Department, Central University Hospital of Asturias, Asturias, Spain b Department of Cardiology, Central University Hospital of Asturias, Asturias, Spain * Corresponding author at: Cardiac Surgery Department, Hospital Universitario Central de Asturias, Avenida del Hospital Universitario Central de Asturias, 33011, Oviedo, Espan˜a, 985108000. EXT: 36262 Email: [email protected] (R. Diaz). Received 22 March 2015; accepted 25 March 2015; online published-ahead-of-print 17 April 2015
References [1] Crudeli E, Lazzeri C, Stefa`no P, Chiostri M, Blanzola C, Rossi A, et al. Age as a Prognostic Factor in Patients with Acute Coronary Syndrome undergoing Urgent/Emergency Cardiac Surgery. Heart Lung Circ 2015;(Feb 20). pii: S1443-9506(15)00081-5. http://dx.doi.org/10.1016/j.hlc.2015.02.007. [Epub ahead of print]. [2] Nashef SA, Roques F, Sharples LD, Nilsson J, Smith C, Goldstone AR, et al. EuroSCORE II. Eur J Cardiothorac Surg 2012;41:734–44. [3] D’Ascenzo F, Cavallero E, Biondi-Zoccai G, Moretti C, Omede` P, Bollati M, et al. Use and misuse of multivariable approaches in interventional cardiology studies on drug-eluting stents: a systematic review. J Interv Cardiol 2012;25:611–21. [4] Afilalo J, Alexander KP, Mack MJ, Maurer MS, Green P, Allen LA, et al. Frailty assessment in the cardiovascular care of older adults. J Am Coll Cardiol 2014;63:747–62.
© 2015 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier Inc. All rights reserved.
