Limit your waist size to half of your height.

Sir,

The article entitled “Anthropometric variables to coronary artery disease risk factors” by Patil, is interesting, though I would like to highlight a few limitations. The study has been done seven years before its publication and that might affect a few crucial findings of the study. The waist circumference (WC) and Body Mass Index (BMI) cutoffs used in the study are different from those currently advocated. The cutoffs suggested for waist to height ratio (WHtR) seem to be empiric as no reference has been cited for the same. It is worthwhile noting that by having lower cutoffs, the sensitivity of a parameter can be enhanced significantly.

Though with these limitations, the paper has strengthened the claim of Index of Central Obesity (ICO – Waist to height ratio) as a better parameter. ICO was proposed as early as 2007[1] by our own group as a better parameter of central obesity. During the conceptualization of ICO, WC cutoffs suggested for various races and both genders were compared with their average heights. The interesting finding was that the need for different gender and race-specific cutoffs can be largely attributable to the differences in their heights. Moreover, by virtue of taking height into consideration, ICO has the potential to come out as a useful tool for defining central obesity among children. ICO has been shown to strongly correlate with insulin resistance among children[2] as well as adults.[3]

ICO has been validated as a better alternative to WC in defining metabolic syndrome (MS) among the diabetic as well as non-diabetic population.[4] In addition to being applicable across races and genders it has been shown to be more sensitive and specific in identifying people with MS and people at high risk of cardiovascular disease. Several other researchers have endorsed ICO as a better predictor of cardiovascular risk,[56] obesity[7] and MS,[8] though there was a concern raised regarding the diverse terminologies being used.[9]

A paper proposing the use of ICO in the definition of MS has been recently accepted[10] and is in press. It would be of great academic interest to look at the cutoffs suggested for ICO in different studies, a few already published and others ongoing. In addition to the academic value ICO is very much useful in spreading a health awareness message among the community – “If your waist size is more than half of your height, please consult your doctor.” For those at risk I would prefer a message – “Limit your waist size to half of your height.”