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Original article

Vol. 144 No. 3132 (2014)

Impact of Body Mass Index on mortality in Swiss hospital patients with ST-elevation myocardial infarction: does an obesity paradox exist?

  • Fabienne Witassek
  • Matthias Schwenkglenks
  • Paul Erne
  • Dragana Radovanovic
Cite this as:
Swiss Med Wkly. 2014;144:w13986


BACKGROUND: The obesity paradox refers to the phenomenon that obese patients seem to have a better outcome than normal weight patients in a variety of disease conditions. The aim of this study was to investigate the impact of Body Mass Index (BMI) on mortality in patients with ST-elevation myocardial infarction (STEMI) who underwent percutaneous coronary intervention (PCI).

METHODS: Between January 2005 and July 2012, the Swiss AMIS Plus registry enrolled 6,938 patients with acute STEMI who underwent PCI. These patients were stratified into 5 BMI groups according to the classification system of the World Health Organisation. The odds for in-hospital mortality according to BMI groups were analysed using logistic regression with normal weight patients as the reference.

RESULTS: Crude in-hospital mortality rates showed a U-shaped distribution between BMI groups, with the lowest mortality in obese class I patients (2.0%) and the highest mortality in underweight patients (9.0%). The odds for in-hospital mortality were significantly lower for obese class I (OR 0.56; 95% CI 0.35–0.91) and significantly higher for underweight patients (OR 2.72; 95% CI 1.14–6.48) compared to the normal weight group and odds ratios showed a U-shaped distribution. After adjustment for covariates, the odds ratios maintained a U-shape distribution albeit the differences between BMI groups were no longer significant.

CONCLUSION: This study showed that the lower crude in-hospital mortality of obese class I patients can be partly explained by lower age and lower co-morbidity rates. However, further studies are needed to investigate favourable factors associated with class I obesity.


  1. Chrysant SG, Chrysant GS. New insights into the true nature of the obesity paradox and the lower cardiovascular risk. J Am Soc Hypertens. 2013;7(1):85–94.
  2. McAuley PA, Blair SN. Obesity paradoxes. J Sports Sci. 2011;29(8):773–82.
  3. Amundson DE, Djurkovic S, Matwiyoff GN. The obesity paradox. Crit Care Clin. 2010;26(4):583–96.
  4. Buettner HJ, Mueller C, Gick M, Ferenc M, Allgeier J, Comberg T, et al. The impact of obesity on mortality in UA/non-ST-segment elevation myocardial infarction. Eur Heart J. 2007;28(14):1694–701.
  5. Kadakia MB, Fox CS, Scirica BM, Murphy SA, Bonaca MP, Morrow DA. Central obesity and cardiovascular outcomes in patients with acute coronary syndrome: observations from the MERLIN-TIMI 36 trial. Heart. 2011;97(21):1782–7.
  6. Sierra-Johnson J, Wright SR, Lopez-Jimenez F, Allison TG. Relation of body mass index to fatal and nonfatal cardiovascular events after cardiac rehabilitation. Am J Cardiol. 2005 Jul;96(2):211–4.
  7. Lavie CJ, Milani RV, Ventura HO. Obesity and cardiovascular disease: risk factor, paradox, and impact of weight loss. J Am Coll Cardiol. 2009;53(21):1925–32.
  8. Angeras O, Albertsson P, Karason K, Ramunddal T, Matejka G, James S, et al. Evidence for obesity paradox in patients with acute coronary syndromes: a report from the Swedish Coronary Angiography and Angioplasty Registry. Eur Heart J. 2012 Sep 4.
  9. World Health Organization. Global status report on noncommunicable diseases. Geneva, Switzerland: World Health Organization. p. v.
  10. Kosuge M, Kimura K, Kojima S, Sakamoto T, Ishihara M, Asada Y, et al. Impact of body mass index on in-hospital outcomes after percutaneous coronary intervention for ST segment elevation acute myocardial infarction. Circ J. 2008;72(4):521–5.
  11. Das SR, Alexander KP, Chen AY, Powell-Wiley TM, Diercks DB, Peterson ED, et al. Impact of body weight and extreme obesity on the presentation, treatment, and in-hospital outcomes of 50,149 patients with ST-Segment elevation myocardial infarction results from the NCDR (National Cardiovascular Data Registry). J Am Coll Cardiol. 2011;58(25):2642–50.
  12. Wienbergen H, Gitt AK, Juenger C, Schiele R, Heer T, Towae F, et al. Impact of the body mass index on occurrence and outcome of acute ST-elevation myocardial infarction. Clin Res Cardiol. 2008;97(2):83–8.
  13. Oreopoulos A, Padwal R, Norris CM, Mullen JC, Pretorius V, Kalantar-Zadeh K. Effect of obesity on short- and long-term mortality postcoronary revascularization: A meta-analysis. Obesity. 2008;16(2):442–50.
  14. Radovanovic D, Erne P. AMIS Plus: Swiss registry of acute coronary syndrome. Heart. 2010;96(12):917–21.
  15. Stauffer JC, Goy JJ, Duvoisin N, Radovanovic D, Rickli H, Erne P. Dramatic effect of early clopidogrel administration in reducing mortality and MACE rates in ACS patients. Data from the Swiss registry AMIS-Plus. Swiss Med Wkly. 2012;142:w13573.
  16. World Health Organization (2009) Global Database on Body Mass Index: BMI Classification. [database on the Internet] [cited 2014 Jan 20.]. Available from:
  17. Yusuf S, Hawken S, Ounpuu S, Dans T, Avezum A, Lanas F, et al. Effect of potentially modifiable risk factors associated with myocardial infarction in 52 countries (the INTERHEART study): case-control study. Lancet. 2004;364(9438):937–52.
  18. Charlson ME, Pompei P, Ales KL, MacKenzie CR. A new method of classifying prognostic comorbidity in longitudinal studies: development and validation. J Chronic Dis. 1987;40(5):373–83.
  19. Goldberg RJ, Cui J, Olendzki B, Spencer F, Yarzebski J, Lessard D, et al. Excess body weight, clinical profile, management practices, and hospital prognosis in men and women after acute myocardial infarction. Am Heart J. 2006;151(6):1297–304.
  20. Gurm HS, Whitlow PL, Kip KE. The impact of body mass index on short- and long-term outcomes inpatients undergoing coronary revascularization. Insights from the bypass angioplasty revascularization investigation (BARI). J Am Coll Cardiol. 2002;39(5):834–40.
  21. Nikolsky E, Stone GW, Grines CL, Cox DA, Garcia E, Tcheng JE, et al. Impact of body mass index on outcomes after primary angioplasty in acute myocardial infarction. Am Heart J. 2006;151(1):168–75.
  22. Romero-Corral A, Montori VM, Somers VK, Korinek J, Thomas RJ, Allison TG, et al. Association of bodyweight with total mortality and with cardiovascular events in coronary artery disease: a systematic review of cohort studies. Lancet. 2006;368(9536):666–78.
  23. Oreopoulos A, McAlister FA, Kalantar-Zadeh K, Padwal R, Ezekowitz JA, Sharma AM, et al. The relationship between body mass index, treatment, and mortality in patients with established coronary artery disease: a report from APPROACH. Eur Heart J. 2009;30(21):2584–92.
  24. Hastie CE, Padmanabhan S, Slack R, Pell AC, Oldroyd KG, Flapan AD, et al. Obesity paradox in a cohort of 4880 consecutive patients undergoing percutaneous coronary intervention. Eur Heart J. 2010;31(2):222–6.
  25. Lazzeri C, Valente S, Chiostri M, Attana P, Picariello C, Sorini Dini C, et al. Impact of age on the prognostic value of body mass index in ST-Elevation myocardial infarction. Nutr Metab Cardiovasc Dis. 2013;23(3):205–11.
  26. von Haehling S, Anker SD. Cachexia as major underestimated unmet medical need: Facts and numbers. Int J Cardiol. 2012;161(3):121–3.
  27. Heymsfield SB. Does Body Mass Index Adequately Convey a Patient’s Mortality Risk? (vol 309, pg 87, 2013). Jama – J Am Med Assoc. 2013;309(5):442–.
  28. Lavie CJ, De Schutter A, Patel DA, Romero-Corral A, Artham SM, Milani RV. Body composition and survival in stable coronary heart disease: impact of lean mass index and body fat in the “obesity paradox”. J Am Coll Cardiol. 2012;60(15):1374–80.
  29. Fischer-Posovszky P, Wabitsch M, Hochberg Z. Endocrinology of adipose tissue – an update. Horm Metab Res. 2007;39(5):314–21.

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