Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Waist-hip ratio should replace body mass index as indicator of mortality risk in older people

Older people with high waist-hip ratios (WHRs) have a higher mortality risk than those with a high body mass index, or BMI, a new study reveals.

Whereas justifiable attention is given to the increasing problem of obesity in the general population, far less is known about the relationship between obesity and mortality in older people, or how mortality risk should be estimated. The excess health risks associated with having a high BMI are known to decline with age, yet expert bodies such as the National Institutes of Health and the World Health Organisation have continued to use in older people the same BMI criteria as for other age groups.

Today’s study, published in the American Journal of Clinical Nutrition, was carried out by a team based at the London School of Hygiene & Tropical Medicine. It sought to investigate the association of BMI, waist circumference (WC) and WHR with mortality and cause-specific mortality. The researchers studied 14,833 patients aged over 75 from 53 family practices in the UK; the subjects underwent a health assessment that included taking body measurements and a follow-up (with a median of 5.9 years) for mortality.

The findings confirmed that the current guidelines for BMI-based risk categories overestimate the risks of excess weight in people aged over 75 and are inappropriate for older men and women. This concurs with a previous study that found BMIs of 25-27 not to be a risk factor for all-cause and cardiovascular mortality in those aged 65 and over 1. Most consistently, the data highlighted the risk of having a low BMI, with people in the lowest quintile (less than 23 in men and less than 22.3 in women) demonstrating the highest risk of death for total mortality and for major causes of death. Very underweight men (those with a BMI of under 18.5) were found to be particularly at risk.

‘An explanation for the lack of a positive association with BMI and mortality at older ages is that, in older persons, BMI is a poor measure of body fat’, say the authors. ‘The measurement of weight does not differentiate between fat and fat-free mass, and fat-free mass (especially muscle) is progressively lost with increasing age

Waist circumference (WC) has been proposed as an alternate or additional measure of obesity. The study found no association with waist circumference and mortality. The authors continue: ‘A limitation of WC alone as a measure is that it takes no account of body composition, whereas WHR is a measure of body shape and to some extent of lower trunk adiposity [abdominal fat]. Although it is possible theoretically for high WHR to coexist with thinness, our data show that those with high WHR had higher-than-average waist and average hip circumferences. We conclude that the association observed for WHR and mortality is probably explained by abdominal adiposity’.

The authors recommend that the current BMI-based health risk categories to define the burden of disease related to adult overweight and obesity be reviewed, as they are not appropriate for those over 75. They suggest that WHR should instead be used in this age group because of its positive relation with risk of death, and that attention should also be paid to the problem of underweight in old age.

To interview the authors, please contact the London School of Hygiene & Tropical Medicine Press Office on 020 7927 2073.

Lindsay Wright | alfa
Further information:

More articles from Studies and Analyses:

nachricht Diagnoses: When Are Several Opinions Better Than One?
19.07.2016 | Max-Planck-Institut für Bildungsforschung

nachricht High in calories and low in nutrients when adolescents share pictures of food online
07.04.2016 | University of Gothenburg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Ice shelf vibrations cause unusual waves in Antarctic atmosphere

25.10.2016 | Earth Sciences

Fluorescent holography: Upending the world of biological imaging

25.10.2016 | Power and Electrical Engineering

Etching Microstructures with Lasers

25.10.2016 | Process Engineering

More VideoLinks >>>