Target value of intraabdominal fat area for improving coronary heart disease risk factors

Comparison between volunteer- and expert-led versions of a community-based weight-loss intervention

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We compared the effects of volunteer- and expert-led weight-loss intervention.

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Participants were instructed to maintain a well-balanced, low-energy diet.

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The completion proportions was significantly higher in the expert-led group.

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The degree of body weight change was similar for both groups.

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Such programs could be an alternative strategy for low-cost obesity management.

This study compared the effect of volunteer- and expert-led versions of a community-based weight-loss intervention in a non-randomized comparative trial conducted in Ibaraki, Japan from 2016 to 2017. Participants were 145 Japanese adults with overweightness or obesity, aged 20–69 years, with 77 in a volunteer-led group and 68 in an expert-led group. Both groups received the same program content and intervention period. Community volunteers were trained in four or five 3-hour training sessions while experts were highly trained and experienced professionals in the fields of exercise and nutrition prescription. Participants were also instructed to maintain a well-balanced, low-energy diet. The primary outcome measure was body weight change. In the volunteer- and expert-led groups, 58 of 77 (75%) and 61 of 68 (95%) participants completed the 12-week intervention, respectively. The mean (95% confidence interval, CI) weight loss of the volunteer-led group was 6.4 (95% CI: 5.6–7.2) kg, corresponding to 8.9% of initial body weight, while that of the expert-led group was 6.3 (95% CI: 5.5–7.1) kg, corresponding to 8.2% of the initial body weight. The proportion of participants who completed the course was significantly higher in the expert-led group (P < 0.05); however, the degree of the body weight change was similar for both groups. With improvement in the completion proportion of the volunteer-led weight-loss interventions, such programs could be an alternative strategy for the wide-scale dissemination of low-cost obesity management.

Dietary modification reduces serum angiopoietin-like protein 2 levels and arterial stiffness in overweight and obese men

PURPOSE

Weight loss can reduce obesity-induced arterial stiffening that is attributed to decreased inflammation. Angiopoietin-like protein 2 (ANGPTL2) is a pro-inflammatory adipokine that is upregulated in obesity and is important in the progression of atherosclerosis and cardiovascular disease. The purpose of this study is to investigate the effects of dietary modification on circulating ANGPTL2 levels and arterial stiffness in overweight and obese men.

METHODS

Twenty-two overweight and obese men (with mean age of 56 ± 2 years and body mass index of 28.6 ± 2.6 kg/m2) completed a 12-week dietary modification program. We measured the arterial compliance and β-stiffness index (as the indices of arterial stiffness) and serum ANGPTL2 levels before and after the program.

RESULTS

After the 12-week dietary modification, body mass and daily energy intake were significantly reduced. Arterial compliance was significantly increased and β-stiffness index was significantly decreased after the 12-week dietary modification program. Serum ANGPTL2 levels were significantly decreased. Also, the changes in arterial compliance were negatively correlated with the changes in serum ANGPTL2 levels, whereas the changes in β-stiffness index were positively correlated with the changes in serum ANGPTL2 levels.

CONCLUSION

These results suggest that the decrease in circulating ANGPTL2 levels can be attributed to the dietary modification-induced reduction of arterial stiffness in overweight and obese men.

Increasing Physical Activity Might Be More Effective to Improve Foot Structure and Function Than Weight Reduction in Obese Adults

Obesity is reported to be an important factor affecting foot structure and function. For obese individuals, weight reduction or increasing weight physical activity could be an effective approach to improve foot structure and function. The present study sought to determine the effect of weight reduction and increasing physical activity on foot structure and function in obese Japanese and to investigate which intervention is more beneficial. The participants were divided into the weight reduction group (n = 30; body mass index 29.0 ± 2.5 kg/m²), with the intervention consisting of dietary modification, and the increasing physical activity group (n = 15; body mass index 28.2 ± 3.1 kg/m²), with the intervention consisting of walking and jogging. A 3-dimensional foot scanner was used to measure the foot anthropometric data with the participants both sitting and standing. The dorsum height declined and the arch stiffness index increased after the weight reduction intervention, and the truncated foot length decreased and the arch stiffness index increased after the increasing physical activity intervention (p <.05). The arch height index showed a downward trend after the weight reduction intervention (p = .060) and an upward trend after the increasing physical activity intervention (p = .069). Moreover, a greater change was found in the increase of the dorsum height and arch height index and decrease of the truncated foot length in the increasing physical activity group than in the weight reduction group (p <.05). These findings suggest that increasing physical activity might be more effective to improve foot structure and function than weight reduction in obese adults.

Does Weight Reduction Affect Foot Structure and the Strength of the Muscles That Move the Ankle in Obese Japanese Adults?

Obesity is considered a major influential factor of foot structure and function. It has been reported to result in detrimental alterations of foot structure indicators and a decrease in muscle strength, which can lower the quality of life and increase the morbidity of obesity. The purpose of the present study was to determine the effect of weight reduction on foot structure and the strength of the muscles that move the ankle in obese adults. A total of 33 obese Japanese participants (mean body mass index 28.49 ± 2.87 kg/m²) without an exercise habit participated in a 12-week dietary modification program. Their foot structure indicators were measured using a 3-dimensional foot scanner, and the strength of the muscles that move the ankle was assessed using a dynamometer. After the dietary modification, the mean body weight reduction was 7.49 ± 4.10 kg (9.38%; 77.82 ± 13.26 kg before and 70.33 ± 11.37 kg after; p <.001). The wide foot indicators, including the forefoot girth, rearfoot width, and instep girth, had decreased significantly (p <.05), and the decreases correlated positively with the weight reduction. Regarding the strength of the muscles that move the ankle, except for dorsiflexion, all the measured peak torque values per body weight had increased significantly (p <.01). These results suggest that the weight reduction induced by a 12-week dietary modification results in thinner feet and increased strength of the muscles that move the ankle.

Equation to estimate visceral adipose tissue volume based on anthropometry for workplace health checkup in Japanese abdominally obese men

The purpose of this study was to develop a new equation model for predicting abdominal visceral adipose tissue (VAT) volume using anthropometric values for workplace health checkup and to clarify the association between metabolic risk factors and measured and predicted VAT volumes. Two hundred sixty male workers (200 for derivation group and 60 for validation group) participated in the cross-sectional study. The anthropometric variables and VAT volume were measured with 24 consecutive magnetic resonance images. Measurements in the validation group also included metabolic risk factors, i.e. blood pressure, HDL cholesterol, triglyceride, fasting glucose and HbA1c. Using multiple regression analyses for the derivation group, we determined the best prediction equation for abdominal VAT volume with a variance of 47% as follows: 47.03 age+117.79 BMI+74.18 waist circumference -8,792.7. In our validation group, the correlation coefficient between the measured and predicted VAT volumes was 0.74 (p<0.01). Furthermore, blood pressure, fasting glucose and HbA1c correlated with both measured and predicted VAT volumes. This study suggests that the equation model has potential to assess VAT accumulation levels in workers health checkup where CT and MRI are not available.

Obesity as predictor of postoperative outcomes in liver transplant candidates: Review of the literature and future perspectives

BACKGROUND

Current American and European guidelines consider a pre-transplant BMI ≥40kg/m² as a relative contraindication for liver transplantation but this recommendation is graded as uncertain and requires further research. Moreover, conflicting results are reported on the predictive value of BMI 30-39.9kg/m² on post-transplant complication and mortality risk.

AIM

This study analyzed the data of the literature on the effect of all three BMI classes of obesity on postoperative outcomes in liver transplantation.

MATERIALS AND METHODS

A PubMed and Cochrane Library search was conducted from inception to October 2015.

RESULTS

Analysis of the literature demonstrates that discrepancies among studies are mainly either due to limitations of BMI per se, the different BMI cut-offs used to select patients with obesity or reference group and the different outcomes considered. Moreover, the evaluation of visceral adipose tissue and the detrimental effect of muscle mass reduction in presence of obesity are never considered.

CONCLUSIONS

BMI assessment should be used as a preliminary method to evaluate obesity. Subsequently, the assessment of visceral adipose tissue and muscle mass should complete the preoperative evaluation of liver transplant candidates. This innovative approach could represent a new field of research in liver transplantation.

Weight loss maintenance for 2 years after a 6-month randomised controlled trial comparing education-only and group-based support in Japanese adults

OBJECTIVE

Our previous study, a 6-month randomised controlled trial, demonstrated that a group-based support promoted weight loss as compared to an education-only intervention. The purpose of this study was to examine weight loss maintenance for 2 years.

METHODS

Originally, 188 overweight Japanese adults, aged 40-65 years, were randomly assigned to 3 groups: control, education-only or group-based support. After the 6-month intervention, 125 participants in the education-only and the group-based support groups were followed up for 2 years. The primary outcome was the amount of weight lost. The participants were retrospectively grouped into quartiles of percent weight loss for secondary analyses.

RESULTS

At the end of follow-up, the amount of weight lost in the education-only and the group-based support groups was the same (3.3 kg). Secondary analyses using data of those who completed the study (n = 100) revealed that the participants in the highest quartile of percent weight loss significantly increased their step counts and moderate-to-vigorous physical activity compared with the lowest quartile. No significant differences were observed in the energy intake among the four groups.

CONCLUSION

The effects of group-based support disappear within 2 years. Increasing physical activity may be a crucial factor for successful maintenance of weight loss.

Efficiency of a free-living physical activity promotion program following diet modification for fat loss in Japanese obese men

The aim of the current study was to examine the efficiency of a free-living physical activity promotion (PAP) program following a diet modification program for fat loss. Fifty obese men, aged 51.4±7.0 y, received a 6-mo regimen consisting of 2 phases. Weekly 90-min free-living PAP sessions were provided for 3 mo immediately after a 3-mo diet modification phase. Fat mass (FM) was measured at baseline and at months 3 and 6 using dual energy X-ray absorptiometry. The time spent in moderate-vigorous physical activity (MVPA) was monitored by a validated single-axis accelerometer. The total energy intake of all participants was assessed at baseline and during weeks 9 and 10 of both the diet modification and PAP programs. The change (Δ) in FM was -1.4±1.9 kg (p<0.05) during the PAP program after the diet modification program (-4.3±2.9 kg, p<0.01). Although there was no significant relationship between ΔFM and ΔMVPA during the PAP phase (p=0.11), MVPA was significantly increased during the PAP phase (+76.0±146.5 min/wk, p<0.01). However, a significant correlation was observed between energy intake/weight and MVPA during the PAP program (r=0.39). Our results suggest that the magnitude of expected FM loss induced by an increase in PA may be suppressed as a result of increased energy intake, even during a PAP program after a diet modification program.

Clinical utility of visceral adipose tissue for the identification of cardiometabolic risk in white and African American adults

BACKGROUND

Visceral adipose tissue (VAT) has been identified as a harmful fat depot, and sex and race differences in VAT have been reported in white and African Americans.

OBJECTIVES

We determined the clinical utility of VAT in the identification of individuals at elevated cardiometabolic risk in white and African American adults and compared the clinical utility with measures obtained by using dual-energy X-ray absorptiometry (DXA) and anthropometric measures.

DESIGN

The sample included 429 white women, 311 African American women, 406 white men, and 100 African American men who were 18-74 y of age. VAT was measured by using computed tomography, fat mass (FM) and percentage of body fat were measured by using DXA, and waist circumference (WC) and BMI were assessed. Receiver operating characteristic curves were used to compare the utility of measures in the identification of participants in the upper quintile of a continuous score derived from principal components analysis of fasting glucose, HDL cholesterol, triglycerides, and blood pressure.

RESULTS

The clinical utility of measures varied across sex-by-race groups. In the overall sample, the areas under the curve were significantly higher for VAT and WC in comparison with the other indicators. Identified VAT thresholds were higher in white men (140 cm(2)) and women (141 cm(2)) than in African American men (82 cm(2)) and women (97 cm(2)).

CONCLUSIONS

VAT and WC showed greater clinical utility than did other obesity measures. Because of the complexity of measuring VAT, the use of WC is recommended for the identification of adults with elevated cardiometabolic risk factors. The Pennington Center Longitudinal Study was registered at clinicaltrials.gov as NCT00959270.

Best single-slice measurement site for estimating visceral adipose tissue volume after weight loss in obese, Japanese men

BACKGROUND

Although the measurement site at L4-L5 for visceral adipose tissue (VAT) has been commonly accepted, some researchers suggest that additional upper sites (i.e., L1-L2 and L2-L3) are useful for estimating VAT volume. Therefore, determining the optimum measurement site remains challenging and has become important in determining VAT volume. We investigated the influence of a single-slice measurement site on the prediction of VAT volume and changes in VAT volume in obese Japanese men.

METHODS

Twenty-four men, aged 30-65 years with a mean BMI of 30 kg/m2, were included in a 12-week weight loss program. We obtained continuous T1-weighted abdominal magnetic resonance images from T9 to S1 with a 1.5-T system to measure the VAT area. These VAT areas were then summed to determine VAT volume before and after the program.

RESULTS

Single-slice images at 3-11 cm above L4-L5 had significant and high correlations with VAT volume at baseline (r=0.94-0.97). The single-slice image with the highest correlation coefficient with respect to VAT volume was located at 5 cm above L4-L5 (r=0.97). The highest correlation coefficient between the individual changes in VAT area and changes in VAT volume was located at 6 cm above L4-L5 (r=0.90).

CONCLUSIONS

Individual measurement sites have different abilities to estimate VAT volume and changes in VAT volume in obese Japanese men. Best zone located at 5-6 cm above L4-L5 may be a better predictor of VAT volume than the L4-L5 image in terms of both baseline and changes with weight loss.

Comparison of education-only versus group-based intervention in promoting weight loss: a randomised controlled trial

AIM

To compare the effectiveness of education-only versus group-based intervention in promoting weight loss.

METHODS

Between April and October 2009, a 6-month randomised controlled trial was conducted at Mito Kyodo General Hospital in Japan (UMIN000001259). The participants were 188 overweight adults (145 women, 43 men) aged 40-65 years. They were randomly assigned to one of three groups: control, moderate or intensive intervention. A single motivational lecture was provided to all three groups, educational materials (textbooks, notebooks, and a pedometer) to the moderate and intensive intervention groups, and group-based support to the intensive intervention group. Amount of weight loss was the primary outcome measure. Secondary outcome measures were components of metabolic syndrome.

RESULTS

Mean ± SD weight loss of participants in the control, moderate and intensive intervention groups was 2.9 ± 4.1, 4.7 ± 4.0 and 7.7 ± 4.1 kg, respectively. Bonferroni post-hoc comparisons revealed all between-group differences to be significant (p < 0.05). Waist circumference decreased in the intensive intervention group more than in the other groups, whereas no significant differences were observed in the other secondary outcome measures.

CONCLUSION

Education-only intervention is a cost-effective method to promote weight loss. Adding group-based intervention further promotes weight loss.

An increase in high-density lipoprotein cholesterol after weight loss intervention is associated with long-term maintenance of reduced visceral abdominal fat

OBJECTIVES

It is generally agreed that excess abdominal fat, in particular visceral abdominal fat (VAF), is related to an increased risk for obesity-related complications. We examined the association between metabolic risk factors and maintaining VAF after weight loss intervention.

METHODS

A total of 54 postmenopausal, obese women who achieved a VAF loss of at least 10% from their baseline values during a 14-week intervention were enrolled as subjects. Body weight, VAF assessed by CT scans, and metabolic risk factors (that is, blood pressure, lipids and glucose) were measured at baseline (week 0), post-intervention (week 15), and at a 2-year follow-up (week 105). The subjects were divided into two groups according to their changes in VAF between weeks 15 and 105 (follow-up period): (1) VAF gainers (VAF changes > 0 cm², n=28) or (2) VAF maintainers (VAF changes ≤ 0 cm², n=26).

RESULTS

The mean change in VAF of all subjects during the 14-week intervention was -34±16 cm² (-29.7±12.3%) (P<0.01). Along with this change, improvements (P<0.05) were observed in all metabolic risk factors except for high-density lipoprotein cholesterol (HDLC). During the follow-up period, there were interactions between the two VAF groups in HDLC, triglycerides (TG) and total cholesterol (TC)/HDLC ratio (all P<0.01). In particular, the HDLC of VAF maintainers improved, and the value at week 105 exceeded baseline level (P<0.01). However, systolic and diastolic blood pressure, TC and low-density lipoprotein cholesterol in the VAF maintainers increased (all P<0.05) back to their mean baseline level despite a further decrease in their VAF during the follow-up period (P<0.01).

CONCLUSIONS

This study shows that long-term maintenance of VAF after weight loss intervention is associated with improvements in HDLC and TG among obese, postmenopausal women.

Intrabdominal fat is related to metabolic risk factors in Hispanic Americans, African Americans and in girls

AIM

This study aimed to test the association of individual adipose depots on cardiometabolic outcomes, whether the association varied by depot and if the associations differed by race/ethnicity or gender in early pubertal children.

METHODS

Three hundred and twenty children (53% male) aged 7-12 years self-identified as African American (AA; n = 114), European American (EA; n = 120) or Hispanic American (HA; n = 86) participated. Insulin dynamics were assessed by intravenous glucose tolerance test; body composition with DXA; fat distribution with CT.

RESULTS

AA had the least fat in each depot and HA had the most. Fat accumulation negatively impacted cardiometabolic outcomes independent of race/ethnicity or gender. AA and females were reproductively more mature. In AA and HA, each measure of adiposity influenced the insulin sensitivity index (S(I)), whereas intra-abdominal adipose tissue (IAAT) did not contribute to S(I) in EA. IAAT was positively associated with blood pressure in AA only. In females, adiposity adversely influenced cardiometabolic outcomes such that total fat mass, IAAT and/or SAAT was inversely associated with S(I), and positively associated with blood pressure and fasting insulin.

CONCLUSION

IAAT is uniquely related to metabolic risk factors in Hispanic Americans, African Americans and girls, suggesting that either the threshold for adverse effects of IAAT is lower, or the IAAT metabolism differs in these groups.

PPARG genotype accounts for part of individual variation in body weight reduction in response to calorie restriction

Several studies indicate that expression of the peroxisome proliferator-activated receptor gamma (PPARG) gene is influenced by calorie restriction. The aim of this study was to investigate whether PPARG gene variations are associated with weight reduction and changes in coronary heart disease (CHD) risk factors in response to a 14-week calorie restriction. In total, 95 middle-aged, Japanese women (BMI>or=25 kg/m2) enrolled as subjects for 14 weeks and attended weekly dietary lectures instructing them on how to consume a nutritionally balanced diet of 1,200 kcal/day. Eight single-nucleotide polymorphisms (SNPs) in the PPARG gene (rs1801282 (Pro/Ala), rs2292101, rs2959272, rs1386835, rs709158, rs1175540, rs1175544, and rs1797912) were analyzed. Body weight decreased significantly (-7.7+/-3.1 kg; -11.3+/-4.4%) during the intervention. Six PPARG SNPs (rs2959272, rs1386835, rs709158, rs1175540, rs1175544, and rs1797912) were significantly associated with the weight reduction, with rs1175544 having the strongest association (P=0.004). No differences across the rs1175544 genotypes were observed in any of the blood analyses or in blood pressure. In a multiple regression analysis, the rs1175544 genotypes accounted for 7% of the total weight reduction variance. These data suggest that one SNP of the PPARG genotype accounted for a significant portion of the total body weight reduction variance in response to a short-term intervention consisting of calorie restriction; however, no relationship was found between these SNPs and the changes in CHD risk factors which accompanied weight loss.

Obesity phenotype and intra-abdominal fat responses to regular aerobic exercise

AIM

To examine the effects of obesity phenotype on abdominal fat responses to regular aerobic exercise.

METHOD

Fifty-seven obese men aged 34-70 years were divided into two groups based on baseline intra-abdominal fat (IF) area measured by computerized tomography: moderate (<200 cm(2)) IF (MIF; n=33, age: 52.9+/-10.6 [SD] yr, body mass index [BMI]: 29.2+/-3.1 kg/m(2)) or high (>or=200 cm(2)) IF (HIF; n=24, age: 53.5+/-9.5 yr, BMI: 30.3+/-3.1 kg/m(2)). The 12-week exercise program consisted primarily of aerobic exercise and met 3 days per week for 90 min per session. Weight, BMI, body composition (by dual-energy X-ray absorptiometry), IF and subcutaneous fat (SF) areas were measured before and after the program.

RESULTS

Regular aerobic exercise reduced weight by 2.3+/-2.2 kg in MIF and 3.2+/-3.0 kg in HIF. HIF reduced significantly more IF area than MIF (15.1+/-26.0 cm(2) in MIF and 43.3+/-41.9 cm(2) in HIF), and the difference remained significant after adjusting for baseline fat mass, weight change and total energy intake during the 12-week aerobic exercise.

CONCLUSION

Exercise-induced IF reduction may be remarkably influenced by obesity phenotype.

The atypical presentation of the metabolic syndrome components in black African women: the relationship with insulin resistance and the influence of regional adipose tissue distribution

The appropriateness of the metabolic syndrome criteria as an indicator of cardiovascular disease risk has been challenged in black Africans. Hence, the aims of this study were (1) to examine the level of agreement between the International Diabetes Federation (IDF) and the National Cholesterol Education Program Adult Treatment Panel III (ATP III) metabolic syndrome criteria, which differ in their emphasis on central obesity; (2) to investigate the degree to which these criteria predict insulin resistance, as estimated by the homeostasis model assessment of insulin resistance (HOMA-IR); and (3) to investigate the extent to which a diagnosis of the metabolic syndrome and insulin resistance may be explained by body fat and its distribution. In 103 normal-weight (body mass index <or=25 kg/m(2), mean: 22.0 +/- 1.8 kg/m(2)) and 119 obese (body mass index >or=30 kg/m(2), mean: 33.9 +/- 5.5 kg/m(2)) urbanized black South African women (27 +/- 7 years old), body composition (dual-energy x-ray absorptiometry), fat distribution (waist and computed tomography), blood pressure, fasting glucose, HOMA-IR, and lipid profiles were measured. Insulin resistance was defined as the upper tertile of HOMA-IR. The overall proportion of individuals who met the IDF and ATP III metabolic syndrome criteria were 13% and 10%, respectively. Agreement was high between the IDF and ATP III metabolic syndrome criteria (kappa = 0.87); however, neither criteria predicted HOMA-IR (kappa = 0.16, 95% confidence interval: 0.05-0.27 and 0.14, 95% confidence interval: 0.05-0.27, respectively). Visceral adipose tissue was the largest contributor to diagnosis of the metabolic syndrome, and waist alone (>80 cm or >88 cm) had an improved specificity (21% or 18% higher, respectively) and positive predictive value (64% or 57% higher, respectively) for identifying insulin resistance compared with the metabolic syndrome criteria. Waist circumference was a better predictor of HOMA-IR than the IDF or ATP III metabolic syndrome criteria in young black African women without known disease. The measurement of waist circumference, as an indicator of disease risk, should therefore be encouraged in the public health setting.

Adipose tissue distribution and risk of metabolic disease: does thiazolidinedione-induced adipose tissue redistribution provide a clue to the answer?

The relative effect of visceral and subcutaneous obesity on the risk of chronic metabolic disease has been a matter of long-term dispute. While ample data support either of the fat depots being causative or associative, valid argument for one depot often automatically belittles the other. Paradigms such as the visceral/portal hypothesis and the acquired lipodystrophy/ectopic fat storage and endocrine hypothesis have been proposed. Nevertheless, neither hypothesis alone explains the entire pathophysiological setting. Treatment of diabetes with thiazolidinediones selectively increases fat partitioning to the subcutaneous adipose depot but does not change visceral fat accumulation. This is in contrast to the preferential visceral fat mobilisation by diet and exercise. Surgical removal of visceral or subcutaneous adipose tissue yields relatively long-lasting metabolic improvement only when combined with procedures that ameliorate adipose tissue cell composition. These studies illustrate that human adipose tissue in different anatomic locations does not work in isolation, and that there is a best-fit relationship in terms of volume and function among different fat depots that needs to be met to maintain the systemic energy balance and to prevent the complications related to obesity.

Effect of weight loss resulting from a combined low-fat diet/exercise regimen on low-density lipoprotein particle size and distribution in obese women

Weight loss resulting from diet interventions has been shown to favorably affect low-density lipoprotein (LDL) particle size and distribution, and, hence, decrease cardiovascular disease risk. However, the effect of a dietary weight loss strategy when combined with exercise, on LDL electrophoretic characteristics, has yet to be tested. This study examined the effect of a weight loss intervention that combined a low-fat diet with moderate endurance training, on LDL particle size and distribution in obese women. Thirty obese, hypercholesterolemic women participated in a controlled longitudinal weight loss trial, which consisted of (1) a 2-week pre-stabilization phase, (2) a 20-week weight loss phase, and (3) a 2-week post-stabilization phase. Weight reduction resulted from a low-fat diet (<30% fat, 50%-60% carbohydrate, 20% protein) combined with an endurance training program (>40 minutes moderate training, 3 times per week). Mean weight loss was 14.8% (P < .01) of initial body weight. Total, LDL cholesterol, and triacylglycerol concentrations decreased (P < .01) by 8.9%, 7.5%, and 27.1%, respectively, whereas high-density lipoprotein cholesterol concentrations increased (P < .01) by 9.9%. No significant differences were noted for LDL peak or integrated particle size. The relative proportion of small, medium, and large particles was not significantly different posttreatment. Estimated cholesterol concentrations in large- and medium-sized LDL particles decreased (P < .05) by 15.3% and 5.9%, respectively, as a result of weight loss. No effect was noted for estimated cholesterol concentrations in small size LDL particles. In conclusion, these findings suggest that weight loss, resulting from a low-fat diet/exercise program, has only a minimal effect on LDL particle size and distribution.

Association of physical inactivity with components of metabolic syndrome and coronary artery disease--the Chennai Urban Population Study (CUPS no. 15)

AIM

The aim of the study was to assess the influence of physical activity on the components of metabolic syndrome (MS) in an urban south Indian population in Chennai.

METHODS

The Chennai Urban Population Study (CUPS) is an epidemiological study involving two residential areas in Chennai in South India. Of the total of 1399 eligible subjects (age > or = 20 years), 1262 individuals participated in the study. MS was diagnosed based on modified Adult Treatment Panel (ATP) III guidelines. Details about the physical activity were collected using questionnaire, which included job-related and leisure-time activities, and specific questions on exercise. Study individuals were then graded as light, moderate and heavy using a scoring system. We assessed the relationship between the grades of physical activity and the components of MS and coronary artery disease (CAD). Insulin resistance was calculated using the homeostasis assessment model (HOMA-IR).

RESULTS

Prevalence of most of the components of MS (diabetes P < 0.001, obesity P = 0.003, abdominal obesity P < 0.001 and hypertension P < 0.001) and MS per se (P < 0.001) increased significantly with decrease in physical activity. Among non-diabetic subjects, HOMA-IR was significantly higher in subjects who did light-grade activity compared with heavy-grade activity (P = 0.041). Logistic regression analysis revealed physical activity to be significantly associated with MS [heavy activity: reference, moderate activity, odds ratio (OR) 1.639, (P = 0.017); light activity: OR 2.289, (P < 0.001)]. Subjects in the light-grade activity group also had higher odds of CAD (OR 2.42, 95% confidence interval 1.40, 4.24, P = 0.011), compared with the heavy-grade activity group.

CONCLUSION

Physical inactivity is associated with the components of MS and CAD in this urban south-Indian population. Lifestyle changes focusing on increasing physical activity could help to prevent the exploding epidemic of MS and CAD in India.

Role of a critical visceral adipose tissue threshold (CVATT) in metabolic syndrome: implications for controlling dietary carbohydrates: a review

There are likely many scenarios and pathways that can lead to metabolic syndrome. This paper reviews mechanisms by which the accumulation of visceral adipose tissue (VAT) may contribute to the metabolic syndrome, and explores the paradigm of a critical VAT threshold (CVATT). Exceeding the CVATT may result in a number of metabolic disturbances such as insulin resistance to glucose uptake by cells. Metabolic profiles of patients with visceral obesity may substantially improve after only modest weight loss. This could reflect a significant reduction in the amount of VAT relative to peripheral or subcutaneous fat depots, thereby maintaining VAT below the CVATT. The CVATT may be unique for each individual. This may help explain the phenomena of apparently lean individuals with metabolic syndrome, the so-called metabolically normal weight (MONW), as well as the obese with normal metabolic profiles, i.e., metabolically normal obese (MNO), and those who are "fit and fat." The concept of CVATT may have implications for prevention and treatment of metabolic syndrome, which may include controlling dietary carbohydrates. The identification of the CVATT is admittedly difficult and its anatomical boundaries are not well-defined. Thus, the CVATT will continue to be a work in progress.