Re: Relation of Body Mass Index to Outcome in Patients With Known or Suspected Coronary Artery Disease

European Heart Journal 2007 28(17):2087-2093; doi:10.1093/eurheartj/
ehm243

Diagnostic performance of body mass index to detect obesity in
patients with coronary artery disease

Abel Romero-Corral1, Virend K. Somers1, Justo Sierra-Johnson3, Michael
D. Jensen2, Randal J. Thomas1, Ray W. Squires1, Thomas G. Allison1,
Josef Korinek1 and Francisco Lopez-Jimenez1,*
1 Division of Cardiovascular Diseases, Department of Internal
Medicine, Gonda 5-368, 200 First Street SW, Rochester, MN 55905, USA
2 Endocrine Research Unit, Mayo Clinic College of Medicine, Mayo
Foundation, Rochester, MN, USA
3 Department of Medicine, Atherosclerosis Research Unit, Karolinska
Insititutet, Stockholm, Sweden

* Corresponding author. Tel: +1 507 284 8087; fax: +1 507 266 7929. E-
mail address: lopez@xxxxxxxx

See page 2047 for the editorial comment on this article (doi:10.1093/
eurheartj/ehm321)

Background: Emerging evidence suggests that a mildly elevated body
mass index (BMI), is related to improved survival and fewer
cardiovascular events in patients with coronary artery disease (CAD).
We hypothesize that these results are related to the poor diagnostic
performance of BMI to detect adiposity, especially in the intermediate
BMI ranges.

Methods and Results: A cross-sectional study of 95 patients with CAD
referred to phase II cardiac rehabilitation. Body fat (BF)% was
estimated by air displacement plethysmography. Height, weight, BMI and
waist circumference were measured the same day. We calculated the
correlation between BMI and both, BF% and lean mass and assessed the
diagnostic performance of BMI to detect obesity defined as a BF% > 25%
in men and > 35% in women. Although BMI had a good correlation with BF
% ( = 0.66, P < 0.0001), it also had a good correlation with lean mass
( = 0.41, P < 0.0001), and BMI failed to discriminate between both (P-
value = 0.72). A BMI 30 kg/m2 had a good specificity (95%; 95% CI, 83-
100) but a poor sensitivity (43%; 95% CI, 32-54) while a BMI 25 kg/m2
had a good sensitivity (91%; 95% CI, 84-97) but a poor specificity
(65%; 95% CI, 42-88) to detect BF%-obesity.

Conclusions: In patients with CAD, BMI does not discriminate between BF
% and lean mass, and a BMI < 30 kg/m2 is a poor index to diagnose
obesity. These findings may explain the controversial findings that
link mild elevations of BMI to better survival and fewer
cardiovascular events in patients with CAD. Body composition
techniques to accurately diagnose obesity in patients with CAD might
be necessary.




.

Relevant Pages