Consider Body Height
In their large cohort study, the authors have shown unequivocally that abdominal obesity as measured by waist circumference predicts the risk of diabetes beyond the body mass index (BMI). From this they conclude that to determine the diabetes risk, waist circumference should always be included with fixed threshold values. I agree unreservedly that a measure of abdominal obesity is essential for preventing risk, but I think that waist circumference is problematic, for the following reason:
A man of 1.50 meters in height would have to accumulate much more abdominal/visceral fat than a man measuring 2 meters in order to reach the same threshold value of 102 cm in waist circumference. A set maximum value in short people therefore underestimates the risk associated with abdominal fat and overestimates it in tall people (1).
This potential problem can be circumvented by using a measure that includes height—for example, the waist to height ratio. Recent studies have shown that this ratio predicts cardiovascular risk to a small but statistically significant degree better than other measures of abdominal obesity (2, 3).
Feller et al have avoided height related distortions in using waist circumference because they adjusted their analyses for body height. It is thus not surprising that the results remain the same if, instead of waist circumference, the waist to height ratio is used. However, this adjustment will not happen in everyday clinical practice, unless the waist to height ratio is used.
PD Dr. med. Harald J. Schneider
Institut für Klinische Chemie und Laboratoriumsmedizin
der Ernst-Moritz-Arndt-Universität Greifswald
17475 Greifswald, Germany
|1.||Schneider HJ, Wittchen HU, Wallaschofski H: Correspondence: Obesity and risk of death. N Engl J Med. 2009; 360: 1043. MEDLINE|
|2.||Gelber RP, Gaziano JM, Orav EJ, Manson JE, Buring JE, Kurth T: Measures of obesity and cardiovascular risk among men and women. J Am Coll Cardiol 2008; 52: 605–15. MEDLINE|
|3.||Schneider HJ, Friedrich N, Klotsche J, et al.: The predictive value of different measures of obesity for incident cardiovascular events and mortality. J Clin Endocrinol Metab. 2010; 95: 1777–85. MEDLINE|
|4.||Feller S, Boeing H, Pischon T: Body Mass Index, Waist circumference, and the risk of type 2 diabetes mellitus—Implications for routine clinical practice. Dtsch Arztebl Int 2010; 107(26): 470–6. VOLLTEXT|