Optimal central obesity measurement site for assessing cardiometabolic and type 2 diabetes risk in middle-aged adults

Abstract

ObjectivesDespite recommendations that central obesity assessment should be employed as a marker of cardiometabolic health, no consensus exists regarding measurement protocol. This study examined a range of anthropometric variables and their relationships with cardiometabolic features and type 2 diabetes in order to ascertain whether measurement site influences discriminatory accuracy. In particular, we compared waist circumference (WC) measured at two sites: (1) immediately below the lowest rib (WC rib) and (2) between the lowest rib and iliac crest (WC midway), which has been recommended by the World Health Organisation and International Diabetes Federation. Materials and MethodsThis was a cross-sectional study involving a random sample of 2,002 men and women aged 46-73 years. Metabolic profiles and WC, hip circumference, pelvic width and body mass index (BMI) were determined. Correlation, logistic regression and area under the receiver operating characteristic curve analyses were used to evaluate obesity measurement relationships with metabolic risk phenotypes and type 2 diabetes. ResultsWC rib measures displayed the strongest associations with non-optimal lipid and lipoprotein levels, high blood pressure, insulin resistance, impaired fasting glucose, a clustering of metabolic risk features and type 2 diabetes, in both genders. Rib-derived indices improved discrimination of type 2 diabetes by 3-7% compared to BMI and 2-6% compared to WC midway (in men) and 5-7% compared to BMI and 4-6% compared to WC midway (in women). A prediction model including BMI and central obesity displayed a significantly higher area under the curve for WC rib (0.78, P=0.003), Rib/height ratio (0.80, P<0.001), Rib/pelvis ratio (0.79, P<0.001), but not for WC midway (0.75, P=0.127), when compared to one with BMI alone (0.74). Data Availability Statement: The data underlying these findings contain potentially identifying patient information. Further information to access these data can be found on the research centre website, http:// www.hrbchdr.com/projects-and-research or through email to patricia. kearney@ucc.ie." may be included in the published manuscript.Funding: This work was supported by a research grant from the Irish Health Research Board (reference HRC/2007/13). The funders had no role in the study design, data collection and analysis, decision to publish or preparation of the manuscript. ConclusionsWC rib is easier to assess and our data suggest that it is a better method for determining obesity-related cardiometabolic risk than WC midway. The clinical utility of rib-derived indices, or alternative WC measurements, deserves further investigation.

Anthropometric discriminators of type 2 diabetes among White and Black American adults

“…Another potential limitation was the measurement of WC at the umbilicus in the ARIC protocol, which differs from the sites commonly use in the other epidemiologic studies (e.g. superior border of the iliac crest) . Because approximately one‐third of the US population with T2DM is undiagnosed, there may be some misclassification of individuals with T2DM in the ARIC cohort that may have biased our effect estimates towards the null.…”

Waist Circumference, Waist-Hip Ratio and Body Mass Index in Assessing Nutritional Status and Central Obesity of Adolescent

“…WHR was calculated by dividing the waist measurement by the hip measurement [8,9]. Derivation of the ROC curves was based on a method by Obuchowski [10] for continuous-scale of gold standards. ROC analyses were performed in order to evaluate the general performance of the BMI, WC and WHR.…”

Accuracy of Waist Circumference Measurement Using the WHO versus NIH Protocol in Predicting Visceral Adiposity Using Bioelectrical Impedance Analysis among Overweight and Obese Adult Filipinos in a Tertiary Hospital

“…First is that other WC measurement sites were not evaluated. Other studies have concluded that WC measurement using the lowest rib was more reproducible and easier to obtain compared to WC-WHO 2,13,14 ; hence its assessment could be clinically relevant.…”

“…Another study in Ireland had similar findings, with WC measured below the lowest rib showing the strongest associations with hypertension, dyslipidemia and DM in both genders. 14 In a study by Ma et al, conducted in Taiwan, WC measurement at the iliac crest (WC-IC) and midway between the lowest rib and iliac crest (WC-mid) were compared -they found greater correlations between WCmid and VFA, blood pressure, blood glucose, hemoglobin A1c and lipid levels. 15 Identification of central obesity using WC-mid was also able to predict the development of DM after 31 months.…”