Obesity and Cardiovascular Diseases - Implications Regarding Fitness, Fatness, and Severity in the Obesity Paradox

Lavie CJ, McAuley PA, Church TS, et al.
J Am Coll Cardiol 2014;63:1345–54

Background

Obesity has been increasing in epidemic proportions in both adults and children over many decades, with a disproportionately higher increase in morbid or class III obesity. Recently, the proportion of the population with more severe, or morbid, obesity has increased to a greater extent than has overweight and mild obesity [1–3]. Nearly 70% of adults are currently classified as either overweight or obese as compared with fewer than 40% just 40 years ago [3].
Recent data have suggested obesity may account for nearly 20% of overall mortality [4].
Obesity adversely affects cardiovascular (CV) hemodynamics, structure, and function, as well as increases the prevalence of most CV diseases [3,5,6]. Progressive declines in physical activity over 5 decades have occurred and have primarily caused the obesity epidemic. Despite the potential adverse impact of overweight and obesity, recent epidemiological data have demonstrated an association of mild obesity and, particularly, overweight on improved survival (the “obesity paradox”, where overweight and at least mildly obese patients with most CV diseases seem to have a better prognosis than do their leaner counterparts) [3,5].
This state-of-the-art paper reviews the obesity paradox in CV diseases. The implications of cardiorespiratory fitness with prognosis are discussed, along with the joint impact of fitness and adiposity on the obesity paradox. Finally, in light of the obesity paradox, the potential value of purposeful weight loss and increased physical activity to affect levels of fitness is reviewed.

Main outcomes

• Overweight and obesity have many adverse effects on hemodynamics and CV structure and function [5].
• Reductions in occupation-related activity and energy expenditure largely explain the marked increased prevalence in obesity noted during recent decades [7].
• In a large meta-analysis [8], the optimal survival occurred at the overweight BMI (25 to 30 kg/m²); these patients had a statistically significant 6% lower mortality than did the normal BMI cohort.
• Several studies demonstrate an obesity paradox in hypertensive subjects [9], CHD [10-13], HF [5, 14-16] and AF [17] – overweight and obese patients with the condition have a considerably better prognosis than patients with normal BMI.
• An obesity paradox does not apply to more morbid obesity, where prognosis is adversely affected [18-23]. This level of severe obesity is a major risk factor for development of CV diseases and is associated with poor prognosis when CV diseases become manifest. Efforts to prevent and treat morbid obesity are therefore urgently needed.
• Fitness remains very predictive and largely negates the adverse effects of body fatness, as well as other traditional CV risk factors, including overweight/obesity, metabolic syndrome/type II diabetes mellitus, and hypertension [24-29]. Although ideal prevention of both age-associated loss in fitness and increase in adiposity may be useful, maintaining or improving fitness is more important than preventing increased adiposity with regard to long-term health outcomes.
• Although better large-scale weight loss intervention trials are needed, the constellation of data still supports purposeful weight reduction in patients with CV diseases, especially in the more severely obesity (probably BMI >35 kg/m² and especially BMI >40 kg/m²). Because fitness is important to improve prognosis, incorporating exercise training and efforts to improve fitness into weight loss programs appears to be particularly beneficial [30,31].

Conclusion

Overweight and obese patients with CV diseases have a better prognosis than do their leaner counterparts. This obesity paradox seems largely apparent in patients with low fitness, whereas those with better fitness have a good prognosis, and no clear obesity paradox is apparent. Although better long-term intervention studies are needed, purposeful weight reduction, and especially incorporating exercise training and improvements in fitness, seems to be beneficial.

Find this article on Pubmed

References

1. Sturm R. Increases in clinically severe obesity in the United States, 1986–2000. Arch Intern Med 2003;163:2146–8.
2. Sturm R. Increases in morbid obesity in the USA: 2000–05. Public Health 2007;121:492–6.
3. Lavie CJ, Milani RV, Ventura HO. Obesity and cardiovascular disease: risk factor, paradox, and impact of weight loss. J Am Coll Cardiol 2009; 53:1925–32.
4. Masters RK, Reither EN, Powers DA, et al. The impact of obesity on US mortality levels: the importance of age and cohort factors in population estimates. Am J Public Health 2013;103:1895–901.
5. Lavie CJ, Alpert MA, Arena R, et al. Impact of obesity and the obesity paradox on prevalence and prognosis in heart failure. J Am Coll Cardiol HF 2013;1:93–102.
6. Bastien M, Poirier P, Lemieux I, Després J-P. Overview of epidemiology and contribution of obesity to cardiovascular disease. Prog Cardiovasc Dis 2014;56:369–81.
7. Church TS, Thomas DM, Tudor-Locke C, et al. Trends over 5 decades in U.S. occupation-related physical activity and their associations with obesity. PLoS One 2011;6:e19657.
8. Flegal KM, Kit BK, Orpana H, Graubard BL. Association of all-cause mortality with overweight and obesity using standard body mass index categories: a systematic review and meta-analysis. JAMA 2013;309: 71–82.
9. Uretsky S, Messerli FH, Bangalore S, et al. Obesity paradox in patients with hypertension and coronary artery disease. Am J Med 2007;120: 863–70.
10. Lavie CJ, De Schutter A, Patel D, et al. Body composition and coronary heart disease mortality: an obesity or a lean paradox? Mayo Clin Proc 2011;86:857–64.
11. Lavie CJ, De Schutter A, Patel DA, et al. 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;60:1374–80.
12. Azimi A, Charlot MG, Torp-Pedersen C, et al. Moderate overweight is beneficial and severe obesity detrimental for patients with documented atherosclerotic heart disease. Heart 2013;99:655–60.
13. Lavie CJ, De Schutter A, Milani RV. Is there an obesity, overweight or lean paradox in coronary heart disease? Getting to the ‘fat’ of the matter. Heart 2013;99:596–8.
14. Lavie CJ, Osman AF, Milani RV, Mehra MR. Body composition and prognosis in chronic systolic heart failure: the obesity paradox. Am J Cardiol 2003;91:891–4.
15. Clark AL, Chyu J, Horwich TB. The obesity paradox in men versus women with systolic heart failure. Am J Cardiol 2012;110: 77–82.
16. Clark AL, Fonarow GC, Horwich TB. Obesity and obesity paradox in heart failure. Prog Cardiovasc Dis 2014;56:409–14.
17. Wanahita N, Messerli FH, Bangalore S, et al. Atrial fibrillation and obesitydresults of a meta-analysis. Am Heart J 2008;155:310–5.
18. Das SR, Alexander KP, Chen AY, 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;58:2642–50.
19. Lavie CJ, Milani RV, Ventura HO. Impact of obesity on outcomes in myocardial infarction: combating the “obesity paradox”. J Am Coll Cardiol 2011;58:2651–3.
20. Payvar S, Kim S, Rao SV, et al. In-hospital outcomes of percutaneous coronary interventions in extremely obese and normal-weight patients: findings from the NCDR (National Cardiovascular Data Registry). J Am Coll Cardiol 2013;62:692–6.
21. Buschur ME, Smith D, Share D, et al. The burgeoning epidemic of morbid obesity in patients undergoing percutaneous coronary intervention: insight from the Blue Cross Blue Shield of Michigan Cardiovascular Consortium. J Am Coll Cardiol 2013;62:685–91.
22. Nagarajan V, Cauthen CA, Starling RC, Tang WH. Prognosis of morbid obesity patients with advanced heart failure. Congest Heart Fail 2013;19:160–4.
23. Lavie CJ, Ventura HO. Analyzing the weight of evidence on the obesity paradox and heart failure: is there a limit to the madness? Congest Heart Fail 2013;19:158–9.
24. Wessel TR, Arant CB, Olson MB, et al. Relationship of physical fitness vs body mass index with coronary artery disease and cardiovascular events in women. JAMA 2004;292:1179–87.
25. Artero EG, Lee DC, Ruiz JR, et al. A prospective study of muscular strength and all-cause mortality in men with hypertension. J Am Coll Cardiol 2011;57:1831–7.
26. Blair SN, Kampert JB, Kohl HW. 3rd Influences of cardiorespiratory fitness and other precursors on cardiovascular disease and all-cause mortality in men and women. JAMA 1996;276:205–10.
27. Lyerly GW, Sui X, Lavie CJ, et al. The association between cardiorespiratory fitness and risk of all-cause mortality among women with impaired fasting glucose or undiagnosed diabetes mellitus. Mayo Clinic Proc 2009;84:780–6.
28. Church TS, LaMonte MJ, Barlow CE, Blair SN. Cardiorespiratory fitness and body mass index as predictors of cardiovascular disease mortality among men with diabetes. Arch Intern Med 2005;165:2114–20.
29. Barry VW, Baruth M, Beets MW, et al. Fitness vs fatness on all-cause mortality: a meta-analysis. Prog Cardiovasc Dis 2014;56:382–90.
30. Balady GJ, Arena R, Siestema K, et al., American Heart Association Exercise, Cardiac Rehabilitation, and Prevention Committee of the Council on Clinical Cardiology, Council on Epidemiology and Prevention, Council on Peripheral Vascular Disease, and Interdisciplinary Council on Quality of Care and Outcomes Research. Clinician’s Guide to cardiopulmonary exercise testing in adults: a scientific statement from the American Heart Association. Circulation 2010;122:191–225.
31. Ades PA, Savage PD, Toth MJ, et al. High-calorie-expenditure exercise: a new approach to cardiac rehabilitation for overweight coronary patients. Circulation 2009;119:2671–8.