Estimation of visceral fat area using criteria for metabolic syndrome: A cross-sectional study

BACKGROUND AND AIMS

The aim of this study was to calculate the visceral fat area (VFA) based on the criteria for metabolic syndrome (MetS).

METHODS

A multiple regression analysis was performed to determine the estimated VFA using data from Japanese participants (2315 men and 1684 women). Receiver operating characteristic curve (ROC) analyses were performed to determine the optimal estimated VFA cutoff for the diagnosis of central obesity. The cutoff was also applied to a second cohort to validate the model.

RESULTS

The estimated VFA was calculated using the MetS criteria, age, and body mass index (adjusted coefficient of determination = 0.682 for men and 0.726 for women). The area under the ROC curve for waist circumference, VFA, and estimated VFA were 0.669, 0.741, and 0.749, respectively, for men and 0.711, 0.787, and 0.803, respectively, for women. The optimal cutoffs for estimated VFA were 128.1 cm² for men and 82.2 cm² for women. Multivariate logistic regression for heart disease revealed that estimated VFA, rather than waist circumference, was associated with a high risk of heart disease.

CONCLUSION

The estimated VFA is a better index of central obesity than waist circumference and VFA for the diagnosis of MetS.

Intra-abdominal fat accumulation is an important predictor of metabolic syndrome in young adults

Metabolic syndrome (MetS), mainly caused by intra-abdominal fat (IAF) accumulation, is an important risk factor for cardiovascular disease. The prevalence of MetS increases rapidly after the age of 40 years, and it is presumed that there is a substantial proportion of MetS in younger age groups. However, the association of IAF with MetS in adults aged 20 to 30 years has not been fully investigated.This study aimed to determine the prevalence of MetS and to verify whether IAF accumulation is associated with other MetS-related metabolic disorders including dyslipidemia, high blood pressure, and high blood glucose among the Japanese population in their 20s.In this cross-sectional study, IAF area (IAFA) and MetS-related metabolic parameters were evaluated in university students in their 20s (n = 1822, 21.5 ± 1.5 years). IAFA was measured using a non-invasive device, DUALSCAN, which can be readily measured through the dual impedance method. The participants were divided into four groups according to IAFA: 0-49.9, 50-74.9, 75-99.9, and ≥100 cm.MetS was prevalent in 3.3% and 0.0% of the males and females, respectively, according to the Japanese criteria of MetS. The sex- and lifestyle-adjusted odds ratios (ORs) for the three metabolic component levels of Mets were elevated in the larger IAFA groups compared to the smallest IAFA group, according to the level of IAFA. The levels particularly increased in participants with abdominal obesity, defined by both, IAFA and waist circumference rather than by waist circumference alone.IAF accumulation was significantly associated with MetS-related metabolic disorders in young adults. An evaluation of IAFA may contribute to the early prediction of the risk of developing MetS in the future.

Development of waist circumference percentiles for Japanese children and an examination of their screening utility for childhood metabolic syndrome: a population-based cross-sectional study

BACKGROUND

In Japan, waist circumference (WC) percentiles to screen for childhood metabolic syndrome (MetS) are unavailable. The objectives of this study were to develop WC and WC-to-height ratio (WC/Ht) percentile curves by age and sex for Japanese children, and to test their utility in screening for MetS in children with obesity who are otherwise healthy.

METHODS

The WC and WC/Ht percentiles were developed using the LMS method of summarizing growth standards, which monitors changing skewness (L), medians (M), and coefficients of variation (S) in childhood distributions. A representative dataset was used, which consisted of 3,634 boys and 3,536 girls aged 4.5-12.75 years in Shizuoka prefecture, Japan, between 2010 and 2012. Children who were obese (355 boys and 230 girls) aged 6-12 years from Osaka prefecture, Japan, were screened for childhood MetS using the new percentiles and the International Diabetes Federation's (IDF's) definition of MetS.

RESULTS

The number of participants with certain metabolic abnormalities (high systolic and diastolic blood pressure, and a high level of triglycerides) was significantly higher in boys aged 10-12 years, with a WC ≥ 90th percentile, than among those with a WC < 90th percentile. None of the participants with a WC < 90th percentile exhibited two or more metabolic abnormalities, regardless of their age or sex. Among the participants aged 10-12 years, 11.4 % of boys and 4.4 % of girls with a WC ≥ 90th percentile were diagnosed with MetS.

CONCLUSIONS

The new percentiles may have a certain level of potential to screen Japanese children for childhood MetS in accordance with the IDF definition.

Aging attenuates the association of central obesity with the accumulation of metabolic risk factors when assessed using the waist circumference measured at the umbilical level (the Japanese standard method)

Objective:

The objective of this study was to clarify the generation and gender differences in the association between central obesity and the accumulation of metabolic risk factors (RFs) in the Japanese population.

Material and methods:

A total of 12 389 subjects (age: 18–80 years) without receiving medication for diabetes, dyslipidemia or hypertension were enrolled in this study and divided according to age and gender. In each group, we performed analyses as follows: (1) a receiver operating characteristic (ROC) analysis to evaluate the utility of the waist circumference (WC) for detecting subjects with multiple RFs of metabolic syndrome (MS); (2) a cross-sectional study to examine the relationship between the WC and the odds ratio (OR) for detecting those subjects and (3) a longitudinal study to examine how longitudinal changes (Δ) in WC over a 1-year period affected the values of each metabolic RF.

Results:

With age, the WC cutoff values yielding the maximum Youden index for detecting subjects with multiple RFs increased only in women, and the areas under the curves of the ROC analysis of WC for detecting those subjects decreased in both genders. The positive correlation between the WC and the OR for detecting subjects with multiple RFs became weaker with age, especially in women. In the longitudinal study, the significant correlation between ΔWC and Δ each metabolic RF, except for hypertension, and between ΔWC and Δ the number of RFs became weaker with age in women, whereas the significant correlation between ΔWC and Δ the number of RFs was not affected with age in men. In women aged ⩾60 years, none of the changes in each metabolic RF were significantly associated with ΔWC.

Conclusions:

Aging attenuates the association of central obesity with the accumulation of metabolic RFs, especially in women.

Cut off values for abdominal obesity as a criterion of metabolic syndrome in an ethnic Kyrgyz population (Central Asian region)

BACKGROUND

People of different racial and ethnic backgrounds have a distinct pattern of central fat deposition, thus making it necessary to devise a race based approach for the diagnosis and evaluation of abdominal obesity (AO). This is the first study to determine the optimal waist circumference (WC) cutoff values for definition of AO in an ethnic Kyrgyz population.

METHODS

323 persons of Kyrgyz ethnicity (183 women and 140 men), with a mean age of 51.8 ± 9.5 years old were included in the study. Measurement of blood pressure (BP), anthropometric data (including body mass index calculation and WC measurement), fasting blood sugar, serum lipid parameters and insulin were performed in all examined individuals. Insulin resistance (IR) was considered as HOMA index (insulin × fasting glucose/22.5) ≥ 2.77. Sensitivity and specificity for the presence of IR or two other criteria of MS (according to the international classification, 2009) were calculated by using receiver operating characteristic (ROC) curves for men and women separately.

RESULTS

The optimal sensitivity and specificity obtained from the ROC curves for IR were 88 cm in women (sensitivity of 0.85, 95%CI (0.72-0.93), specificity of 0.58, 95%CI (0.49-0.66)) and 94 cm for men (sensitivity of 0.8, 95% CI (0.65-0.91), specificity of 0.61, 95% CI (0.51-0.71)). The data from the ROC curve for any two other MS criteria confirmed the results and the WC 88 cm in women (sensitivity of 0.82, 95% CI (0.72-0.9), specificity of 0.72, 95% CI (0.62-0.8)) and 94 cm in men (sensitivity of 0.74, 95% CI (0.62-0.84), specificity of 0.73, 95% CI (0.61-0.83)) were corresponded to the optimal sensitivity and specificity.

CONCLUSION

WC ≥ 88 cm and ≥ 94 cm should be used as a criterion for the diagnosis of AO for Kyrgyz women and men respectively based on these results.