0
0
A large prospective cohort study has found that measuring waist circumference alongside body mass index (BMI) modestly improves the ability to predict which postmenopausal women are at higher risk for premature death. The research, led by Aaron K. Aragaki, MS, of the Fred Hutchinson Cancer Center, analyzed data from over 139,000 women enrolled in the Women’s Health Initiative (WHI) and followed for up to 28 years.
While obesity remains a major public health concern, BMI—commonly used to assess obesity—has notable limitations. It reflects total body mass but does not distinguish between fat and lean mass, nor does it indicate where fat is distributed. This is significant because visceral fat, which accumulates around the abdomen, is more metabolically active and linked to higher cardiometabolic and mortality risk.
Waist Circumference: A Simple, Effective Measure
Waist circumference is a simple, inexpensive method to assess visceral adiposity and correlates well with imaging-based measures of visceral fat. However, it is not routinely measured in clinical practice. The study authors argue that combining waist circumference with BMI allows for more personalized risk assessment, particularly if BMI-specific waist thresholds are used.
New Thresholds for Improved Risk Stratification
The International Atherosclerosis Society (IAS) and the International Chair on Cardiometabolic Risk (ICCR) Working Group recently proposed BMI-specific waist circumference thresholds for both women and men. For women, these range from 80 cm for normal weight to 115 cm for the highest obesity category. The study found that stratifying women by both BMI and waist circumference improved the ability to discriminate mortality risk compared to using BMI alone, especially at the 10-year follow-up mark.
-
Women with normal or overweight BMI but large waist circumference had a similar mortality risk as women with obesity and normal waist circumference.
-
Women with obesity and large waist circumference had mortality risks comparable to those in the highest obesity category but with normal waist circumference.
-
The improvement in mortality risk prediction was modest but statistically significant in some cohorts.
-
Waist circumference measurement is quick, inexpensive, and easily understood by patients, and could be integrated into routine clinical care.
Dr. Reema Hamid Dbouk, an obesity medicine specialist, notes that waist circumference is a surrogate for visceral fat and provides valuable information beyond BMI. She also highlights that while the new thresholds are a step toward personalized risk assessment, more research is needed to account for differences in fat distribution by race, ethnicity, and body type.
“Patients with a large waist circumference in any BMI category are at elevated cardiometabolic and mortality risk and may benefit from more aggressive interventions than those with similar BMIs but lower waist circumferences,” the study authors wrote.
Implications for Clinical Practice
These findings support the growing consensus that BMI should not be the sole metric for assessing obesity-related health risks. Supplementing BMI with waist circumference could help clinicians better identify patients at higher risk and tailor interventions accordingly.
:
This article summarizes findings from a recent prospective cohort study and expert commentary. The information is intended for general educational purposes and should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider with any questions regarding a medical condition or health objectives.
