More on Body Fat Cutoff Points–Reply–I
2011; Elsevier BV; Volume: 86; Issue: 6 Linguagem: Inglês
10.4065/mcp.2011.0156
ISSN1942-5546
AutoresAntigone Oreopoulos, Carl J. Lavie, Søren Snitker, Abel Romero‐Corral,
Tópico(s)Thermoregulation and physiological responses
ResumoWe greatly appreciate the interest of Ho-Pham et al in our article1Oreopoulos A Ezekowitz JA McAlister FA et al.Association between direct measures of body composition and prognostic factors in chronic heart failure.Mayo Clin Proc. 2010; 85: 609-617Abstract Full Text Full Text PDF PubMed Scopus (118) Google Scholar and in percentage of body fat (PBF) cutoff points in general. To provide as detailed a response as possible, Oreopoulos has allied herself with Lavie and Romero-Corral, who cowrote the accompanying editorial,2Lavie CJ Milani RV Ventura HO Romero-Corral A Body composition and heart failure prevalence and prognosis: getting to the fat of the matter in the "obesity paradox" [editorial].Mayo Clin Proc. 2010; 85: 605-608Abstract Full Text Full Text PDF PubMed Scopus (86) Google Scholar and Snitker, the author of a recent letter on a related topic3Snitker S Use of body fatness cutoff points [letter to the editor].Mayo Clin Proc. 2010; 85: 1057Abstract Full Text Full Text PDF PubMed Scopus (30) Google Scholar and an unpublished correspondence with Mayo Clinic Proceedings criticizing the use of the World Health Organization (WHO) 1995 Technical Report4World Health Organization (WHO) Physical status: the use and interpretation of anthropometry: report of a WHO expert committee.World Health Organ Tech Rep Ser. 1995; 854: 1-452PubMed Google Scholar to support specific cutoff points for PBF. We enjoyed reading the historical account of the misattribution of the WHO 1995 Technical Report4World Health Organization (WHO) Physical status: the use and interpretation of anthropometry: report of a WHO expert committee.World Health Organ Tech Rep Ser. 1995; 854: 1-452PubMed Google Scholar as recommending specific PBF cutoff points, which 3 of us (A.O., C.J.L., A.R.-C.) have inadvertently used as well.1Oreopoulos A Ezekowitz JA McAlister FA et al.Association between direct measures of body composition and prognostic factors in chronic heart failure.Mayo Clin Proc. 2010; 85: 609-617Abstract Full Text Full Text PDF PubMed Scopus (118) Google Scholar, 5Lavie CJ Milani RV Artham SM Dharmendrakumar PA Ventura HO The obesity paradox, weight loss, and coronary disease.Am J Med. 2009; 122: 1106-1114Abstract Full Text Full Text PDF PubMed Scopus (202) Google Scholar, 6Lavie CJ Milani RV Ventura HO De Schutter A Romero-Corral A Use of body fatness cutoff points [letter reply].Mayo Clin Proc. 2010; 85: 1057-1058Abstract Full Text Full Text PDF PubMed Scopus (6) Google Scholar, 7Romero-Corral A Somers VK Sierra-Johnson J et al.Accuracy of body mass index in diagnosing obesity in the adult general population.Int J Obes (Lond). 2008; 32: 959-966Crossref PubMed Scopus (921) Google Scholar, 8Romero-Corral A Somers VK Sierra-Johnson J et al.Diagnostic performance of body mass index to detect obesity in patients with coronary artery disease.Eur Heart J. 2007; 28: 2087-2093Crossref PubMed Scopus (176) Google Scholar We note that a guideline statement of the American Association of Clinical Endocrinology/American College of Endocrinology9AACE/ACE Obesity Task Force AACE/ACE position statement on the prevention, diagnosis, and treatment of obesity.Endocr Pract. 1998; 4: 297-350Google Scholar and an article by a recognized expert10Grundy SM Obesity, metabolic syndrome, and cardiovascular disease.J Clin Endocrinol Metab. 2004; 89: 2595-2600Crossref PubMed Scopus (942) Google Scholar both define PBF cutoff points of 25% in men and 35% in women for obesity. One of these would probably be a better reference to use, although we admit that neither publication provides any rationale. Incidentally, these cutoff points are close to the means for PBF in the 13,601 adult participants in the Third National Health and Nutrition Examination Survey (NHANES III), which are 24.8% for men and 36.7% for women.7Romero-Corral A Somers VK Sierra-Johnson J et al.Accuracy of body mass index in diagnosing obesity in the adult general population.Int J Obes (Lond). 2008; 32: 959-966Crossref PubMed Scopus (921) Google Scholar The major contribution of the 1995 WHO Technical Report4World Health Organization (WHO) Physical status: the use and interpretation of anthropometry: report of a WHO expert committee.World Health Organ Tech Rep Ser. 1995; 854: 1-452PubMed Google Scholar was to define the normal range of body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) in adults as between 18.5 and 24.9 (with additional thresholds at 30 and 40), later elevated to official standards of both the WHO11World Health Organization (WHO) Obesity: preventing and managing the global epidemic: report of a WHO consultation.World Health Organ Tech Rep Ser. 2000; 894 (1-253.): i-xiiPubMed Google Scholar and the National Institutes of Health.12National Heart, Lung, and Blood Institute Clinical guidelines on the identification, evaluation and treatment of overweight and obesity in adults.http://www.nhlbi.nih.gov/guidelines/obesity/obesity2/index.htmGoogle Scholar The consensus on these numbers provided a foundation for Gallagher et al13Gallagher D Heymsfield SB Heco M Jebb SA Murgatroyd PR Sakamoto Y Healthy percentage body fat ranges: an approach for developing guidelines based on body mass index.Am J Clin Nutr. 2000; 72: 694-701PubMed Google Scholar to propose PBF cutoffs as the empirical age-, sex-, and race-specific PBF correlates of the now canonical BMI thresholds. According to Gallagher et al, a BMI between 25 and 29.9 corresponds to a PBF of 20% to 25% in men and of 32% to 38% in women, generally allowing for a higher PBF with advancing age and in Asians compared with others13Gallagher D Heymsfield SB Heco M Jebb SA Murgatroyd PR Sakamoto Y Healthy percentage body fat ranges: an approach for developing guidelines based on body mass index.Am J Clin Nutr. 2000; 72: 694-701PubMed Google Scholar; the studies of Romero-Corral et al7Romero-Corral A Somers VK Sierra-Johnson J et al.Accuracy of body mass index in diagnosing obesity in the adult general population.Int J Obes (Lond). 2008; 32: 959-966Crossref PubMed Scopus (921) Google Scholar and of Jackson et al14Jackson AS Stanforth PR Gagnon J et al.The effect of sex, age and race on estimating percentage body fat from body mass index: The Heritage Family Study.Int J Obes Relat Metab Disord. 2002; 26: 789-796Crossref PubMed Scopus (448) Google Scholar provide PBF correlates of a BMI of 25 in the same range as Gallagher et al. We used the thresholds of Gallagher et al in our study of patients with chronic heart failure1Oreopoulos A Ezekowitz JA McAlister FA et al.Association between direct measures of body composition and prognostic factors in chronic heart failure.Mayo Clin Proc. 2010; 85: 609-617Abstract Full Text Full Text PDF PubMed Scopus (118) Google Scholar as an example of the obesity paradox, ie, the observation that in some chronic conditions, a high BMI is associated with improved survival. We found that when body composition was quantified as its individual components, a high lean body mass and a low fat mass percentage were independently associated with advantageous prognostic factors; body fat thresholds are important because BMI misclassified body fatness status (in either direction) in a large proportion of our patients,1Oreopoulos A Ezekowitz JA McAlister FA et al.Association between direct measures of body composition and prognostic factors in chronic heart failure.Mayo Clin Proc. 2010; 85: 609-617Abstract Full Text Full Text PDF PubMed Scopus (118) Google Scholar as also shown by Romero-Corral et al in the general population7Romero-Corral A Somers VK Sierra-Johnson J et al.Accuracy of body mass index in diagnosing obesity in the adult general population.Int J Obes (Lond). 2008; 32: 959-966Crossref PubMed Scopus (921) Google Scholar and in a cohort with coronary heart disease.8Romero-Corral A Somers VK Sierra-Johnson J et al.Diagnostic performance of body mass index to detect obesity in patients with coronary artery disease.Eur Heart J. 2007; 28: 2087-2093Crossref PubMed Scopus (176) Google Scholar A debatable aspect of the approach by Gallagher et al is the fact that it allows for a higher degree of obesity in Asians and the elderly. Such group differences are to be expected when a uniform BMI threshold is applied to groups that differ in their relation between PBF and BMI. The finding that health risks are evident at a lower BMI in Asians than in other populations14Jackson AS Stanforth PR Gagnon J et al.The effect of sex, age and race on estimating percentage body fat from body mass index: The Heritage Family Study.Int J Obes Relat Metab Disord. 2002; 26: 789-796Crossref PubMed Scopus (448) Google Scholar begs the question of whether higher PBF cutoffs are indeed appropriate in this group. Only prospective studies of individuals in whom PBF has been measured can ascertain whether Asians and the elderly are particularly tolerant of a high PBF. Nevertheless, the Gallagher et al adjustments for demographics and age are small and do not detract from the soundness of the basic principle. Using universal PBF cutoffs points of 25% in men and 35% in women, we have found that the obesity paradox in patients with coronary heart disease extends not only to BMI but also to PBF,15WHO Expert Consultation Appropriate body-mass index for Asian populations and its implications for policy and intervention strategies.Lancet. 2004; 363: 157-163Abstract Full Text Full Text PDF PubMed Scopus (7944) Google Scholar thereby advancing the understanding of this phenomenon. In another study,16Romero-Corral A Somers VK Sierra-Johnson J et al.Normal weight obesity: a risk factor for cardiometabolic dysregulation and cardiovascular mortality.Eur Heart J. 2010; 31: 737-746Crossref PubMed Scopus (400) Google Scholar we have defined normal weight obesity among 6171 individuals whose BMI was in the normal range (18.5-24.9) as those whose PBF was in the highest tertile, ie, greater than 23.1% in men and greater than 33.3% in women. Normal weight obesity was associated with a high prevalence of metabolic syndrome, similar to that observed in overweight individuals. More importantly, normal-weight obese women had more than a 2-fold increased risk of cardiovascular mortality. In conclusion, our research has shown that PBF cutoffs in the 20% to 25% range in men and 30% to 38% in women are useful to identify individuals at risk of metabolic disease who are possibly "misclassified" by BMI and to provide insights into the obesity paradox as it applies to various conditions. It has not been within the scope of our research to determine whether a hypothetical "elbow" exists on the risk curve, to define actionable trigger points for clinical recommendations, or to examine how any of these might vary by age or ethnicity. We reiterate our call6Lavie CJ Milani RV Ventura HO De Schutter A Romero-Corral A Use of body fatness cutoff points [letter reply].Mayo Clin Proc. 2010; 85: 1057-1058Abstract Full Text Full Text PDF PubMed Scopus (6) Google Scholar for research and guidelines to establish evidence-based cutoff points for PBF, as was done years ago for BMI. More on Body Fat Cutoff PointsMayo Clinic ProceedingsVol. 86Issue 6PreviewTo the Editor: We read with interest the recent article by Oreopoulos et al1 that reported the association between body composition and chronic heart failure. In the article, the authors state that "…WHO [World Health Organization] has also proposed a definition of obesity as greater than 25% body fat in men and greater than 35% body fat in women," with the 1995 WHO Technical Report2 serving as the reference for this statement. As a matter of fact, the mentioned WHO Technical Report makes no recommendation regarding the criteria of percentage of body fat (PBF) for the diagnosis of obesity. Full-Text PDF
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