Central obesity doubles the risk for death in CAD patients
MedWire News: Central obesity, but not body mass index (BMI), is directly associated with increased mortality in coronary artery disease (CAD) patients, US researchers report.
The effect is even observed in patients with a normal BMI, adds the team in the Journal of the American College of Cardiology.
"Our data suggests waist circumference (WC) and waist-hip-ratio (WHR) to be more reliable than BMI in stratifying mortality risk in CAD patients, explain Francisco Lopez-Jimenez (Mayo Clinic, Rochester, Minnesota) and colleagues.
The researchers analyzed data from five studies involving 15,923 individuals with CAD, for whom measures of WC or WHR were available.
After a median follow-up period of 2.3 years there were 5696 reported deaths.
The team found that individuals who were in the highest tertile of central obesity (WC>99 cm and/or WHR>0.98 for men and WC>96 cm and/or WHR>0.93 for women) were at a 70% increased risk for mortality than those in the lowest tertile (WC≤89 and/or WHR≤0.94 for men and WC≤84 cm and/or WHR≤0.86 women).
In contrast, BMI was inversely associated with mortality; patients in the highest BMI tertile (>27.1 or 27.9 kg/m2 for men and women, respectively) were at a 36% lower risk for death than those in the lowest BMI tertile (≤24.1 or 23.7 kg/m2, respectively).
Further analysis revealed that the association between central obesity and increased mortality was even observed in individuals with a normal BMI (18.5-24.9 kg/m2).
Indeed, compared with normal-weight individuals in the lowest tertile of central obesity, risk for death increased 70% among those in the highest tertile.
"These findings might have significant implications for clinical practice, because it is generally accepted that, if BMI is normal, no further measures of obesity are necessary, and no lifestyle modifications to induce weight loss might be recommended," explain the researchers.
In addition, the team found that central obesity was associated with a 93% increased risk for death among individuals with a BMI in the obese category (≥30 kg/m2), suggesting that measures of central obesity are "stronger prognostic markers than BMI in CAD patients, irrespective of BMI."
Lopez-Jimenez et al conclude: "In light of these results, we suggest that WC and/or WHR should be documented in patients with CAD, regardless of their BMI, to improve risk stratification and foster therapeutic recommendations for fat loss."
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By Nikki Withers