June 6, 2005 -- Move over, BMI; another test may do a better job of showing heart disease risk.
People's heart risk could be better shown by their waist-to-tallness ratio (WTR) than by their body mass index (BMI), say German and Austrian researchers. They presented their findings in San Diego at the Endocrine Society's annual meeting.
Research has shown that abdominal fat may be more hazardous than fat in other areas, such as around the hips. But simply checking girth doesn't take proportion into account. That's why the researchers considered height, as well as waistline. The study's heart-risk math works out like this: A man who is 5-feet-10-inches tall should shoot for a waistline that's 38 inches or less. For a 5-foot-5-inch tall woman, the waistline guideline is 34 inches or less.
The researchers found that men should have a WTR of 0.55 or less and women 0.53 or less.
To figure out what your waist should be for your height, take your height in inches and multiply it by 0.55 for men and 0.53 for women. That will give you a fairly good idea of the upper limit of a healthy waistline (in inches) for you.
Crunching the Numbers
The study included more than 48,000 patients of nearly 3,800 primary care offices. Each person's BMI, WTR, waist circumference, hip circumference, and waist-to-hip ratios were noted. A smaller group (about 7,500 people) also got in-depth testing and was followed for a year.
The goal: See which measurement synched up best with a list of 18 single or combined heart risk factors. The answer: WTR, followed by waist circumference, and then BMI.
The waist-to-tallness ratio was "most strongly associated with most risk factors in males and females," write the researchers, who included Harald Schneider of the Max Planck Institute of Psychiatry in Munich, Germany.
"As a consequence, the measurement of the WTS as a simple and the most reliable predictor of cardiovascular risk in primary care is suggested," say Schneider and colleagues.