BACKGROUNDFew studies have used body mass index (BMI), waist-to-hip ratio (WHR) and waist circumference (WC) at the same time to investigate the association between obesity and colorectal adenoma. This study examined the strength of association between colorectal adenoma and obesity using not only BMI, but also WHR and WC.

METHODSSubjects of this study included 1322 asymptomatic patients who underwent colonoscopy for cancer screening from January 2006 to June 2008. Anthropometric measurements, blood test results, and a self-administered questionnaire from each subject were analyzed.

RESULTSFour hundred and fourteen adenoma cases were identified in 1322 subjects. Using univariate analysis, the prevalence of adenoma was associated with BMI and WHR and was higher among the abdominal obesity group using WC guidelines of the Korean Society for the Study of Obesity, but not using WC guidelines of the International Diabetes Federation. In multiple Logistic regression analysis, general obesity (BMI ≥ 25 kg/m(2)) increased the risk of colorectal adenoma (odds ratio (OR), 1.43; 95% confidence interval (CI), 1.05 - 1.94). Also, abdominal obesity by the WC cutoffs and the highest WHR percentile group (WHR ≥ 0.95) were significantly associated with adenoma. Among three measures of obesity, however, only BMI had a persistent association with adenoma after adjusting reciprocally for BMI, WC, and WHR (OR, 1.30; 95%CI, 1.02 - 1.80; and 1.49; 1.06 - 2.10, adjusted for WC and WHR, respectively).

CONCLUSIONThe data suggest that general obesity is associated with an increased risk of colorectal adenoma.

Adult ; Body Mass Index ; Colorectal Neoplasms ; epidemiology ; Female ; Humans ; Male ; Middle Aged ; Obesity ; epidemiology ; Waist Circumference ; physiology ; Waist-Hip Ratio

BACKGROUNDWaist circumference (WC), a proxy measure of central body fat, is a better predictor than overall body fat for cardiovascular risk factors in both adults and children. WC cutoffs have been established in many countries, but the national WC reference has not been developed in China.

OBJECTIVETo study the distribution of WC in a representative group of Chinese children for establishing Chinese WC cutoff points.

METHODSCross-sectional data obtained from 15 mainland provinces and Hong Kong were collected. There were 160,225 children and adolescents aged 7-18 years old in total. The subjects were divided into five regional groups namely costal city, other city, north rural, south rural, and Hong Kong, for analyzing the distribution of WC.

RESULTSA large variation in WC distribution was found among the five groups for both sexes. Coastal city group had the highest P85 WC values consistently from the early school ages to 18-year-old compared with other groups. In contrast, south rural group had P85 values consistently lagged behind not only the city groups but also the north rural group. Hong Kong group had a high P85 WC at early ages, but because of the smaller increments of WC during adolescence, the P85 curve was gradually exceeded by the north rural groups. Catch-up trend was found in the two rural groups since the peak of puberty. These disparities were caused by not only socioeconomic and urban-rural factors but also north-south differences. Because of the regional variation of WC, a "gradient" prevalence of central obesity was prospected among these groups. Comparisons of WC distributions between the Chinese and the U.S.A. or Netherlands demonstrated the necessary of setting up China's own WC cutoffs. Sex and age-specific percentiles were obtained and smoothed by using LMS method.

CONCLUSIONThe data obtained from this study could be used to develop national WC cutoff points for Chinese children and adolescents.

Adolescent ; Child ; China ; epidemiology ; Demography ; Female ; Humans ; Male ; Overweight ; epidemiology ; Waist Circumference ; physiology

Asian Continental Ancestry Group ; Cardiovascular Diseases ; Child ; China ; epidemiology ; Humans ; Overweight ; epidemiology ; Waist Circumference ; physiology

Objective: To investigate the associations of obesity and physical activity with cognition in the elderly. Methods: A cross-sectional survey was conducted from October 2009 to June 2010 among people aged ≥50 years selected through multistage random cluster sampling in Shanghai. The subjects' body weight, body height, waist circumference and hip circumference were measured to calculate body mass index (BMI) and waist-hip ratio (WHR), and the data on self-reported physical activity level were collected through questionnaire survey. A comprehensive battery of cognitive tests was conducted to assess subjects' cognitive functions, including verbal recall, forward digit span (FDS), backward digit span (BDS), and verbal fluency (VF). General linear model was used to examine the associations of BMI, WHR and physical activity with cognition. Results: A total of 7 913 participants were included, with a median age of 60 years. Age, sex, education level, income level, BMI, WHR and physical activity level were significantly associated with cognitive scores in univariate analysis. After adjusted for age, sex, education level and income level, BMI was no longer significantly associated with cognitive scores in all cognitive functions (all P>0.01). WHR was significantly associated with VF score (P<0.01). Abdominally obese participants had lower VF score than non-abdominally obese participants (P<0.01). Physical activity level was significantly associated with all cognitive functions (P<0.01). Compared with participants with moderate physical activity level, participants with low physical activity level had lower scores in all cognitive functions (P<0.01). Conclusion: Abdominal obesity and low physical activity level were negatively associated with cognition level in the elderly, suggesting that waist circumference control and physical activity might help maintain cognition in the elderly.
Aged ; Body Height ; Body Mass Index ; Body Weight ; China ; Cognition/physiology* ; Cross-Sectional Studies ; Exercise ; Humans ; Middle Aged ; Obesity ; Surveys and Questionnaires ; Waist Circumference ; Waist-Hip Ratio

PURPOSE: Visceral fat (VF) is closely associated with many metabolic risk factors and is also known to be a strong predictive factor for severe metabolic complications in adults. But there are only a few studies concerning the association of VF and risk factors for metabolic syndrome (MS) in children and adolescents. In our study, we emphasized the association of VF [measured by VF computed tomography (VFCT)] and risk factors for metabolic syndrome in children and adolescents. MATERIALS AND METHODS: The subjects were outpatients aged 6 to 18 years who underwent VFCT in the family medicine of The Catholic University of Korea from January 2005 to August 2009. There were 82 patients in total (42 children, 40 adolescents). Height, weight, blood pressure (BP), blood tests, body composition analysis and VF were measured. The three groups were also classified by metabolic score. RESULTS: In children, only high density lipoprotein cholesterol (HDL-C) showed a statistically significant difference, while in adolescents, triglyceride, HDL-C, BP, body mass index (BMI), waist circumference (WC) and VFA showed statistically significant differences. In terms of VFA, fasting glucose, BP, BMI, basal metabolic rate (BMR) and WC showed statistically significant differences. BMI showed a statistically significant difference in terms of BP, BMR, WC, VFA and HDL-C. CONCLUSION: There is a need to acknowledge the statistically significant associations of VF and risk factors for MS in children and adolescents. Screening tests for BP, cholesterol, fasting glucose and WC should be given in clinics for children and adolescents so that MS can be detected and its risk factors treated early.
Adolescent ; Body Mass Index ; Child ; Female ; Humans ; Intra-Abdominal Fat/*physiology ; Male ; Metabolic Syndrome X/*epidemiology/metabolism/physiopathology ; Risk Factors ; Waist Circumference/physiology

BACKGROUNDThe key components of metabolic syndrome (MS) are waist circumference, blood pressure, fast blood glucose, high density lipoprotein cholesterol (HDL-c) and triglycerides (TG). These components have, separately and jointly, been associated with an increased risk of cardiovascular diseases. In this study, we aimed to explore the association between MS components and cancer risk in a population-based cohort in China.

METHODSWe established a population-based cohort with 17 779 individuals aged 35 and above at baseline in 2004 and 2005 in Changzhou, Jiangsu Province, China. All participants were face-to-face interviewed to complete a questionnaire and were accepted physical examinations including blood tests for glucose and lipids and physical measurements for obesity and blood pressure. In 2009, a total of 16 284 subjects (6886 men and 9398 women, 91.6%) attended the flow-up interviews and the participants or their family members reported all the hospitalizations and diseases including cancer occurred during the follow-up period. Multivariate Cox regression was used to estimate the hazard ratios (HRs) of metabolic syndrome components and cancer incidence.

RESULTSThere was a dose-response association between cancer risk and the number of MS components presented at baseline (P for trend = 0.012) and the HR (95% confidence interval (CI)) was 2.63 (1.27 - 5.45) for subjects carrying 3 or more metabolic syndrome components after adjustment for possible confounding factors. Specifically, the multivariate-adjusted HRs (95%CIs) for cancer risk in subjects with central obesity, high fasting glucose, low HDL-c were 1.94 (1.01 - 3.74), 2.04 (1.10 - 3.77) and 2.05 (1.09 - 3.88), respectively.

CONCLUSIONSIn this population-based, prospective cohort study in China, we found MS components, e.g., central obesity, high fasting glucose, low HDL-c were risk factors for cancer development. Early intervention of MS components may be also beneficial to reduce cancer burden.

Adult ; Asian Continental Ancestry Group ; Blood Glucose ; physiology ; China ; Female ; Humans ; Male ; Metabolic Syndrome ; epidemiology ; Middle Aged ; Multivariate Analysis ; Neoplasms ; epidemiology ; Prospective Studies ; Triglycerides ; blood ; Waist Circumference ; physiology

OBJECTIVETo examine the association between habitual sleep duration and obesity among Chinese adults.

METHODSThe association of sleep duration and obesity was investigated among 7,094 community-dwelling Chinese adults. Sleep duration was self-reported. In this study, obesity was defined as follows: body mass index (BMI) ⋝ 28 kg/m2, waist circumference (WC) ⋝ 85 cm in men and ⋝ 80 cm in women, and percent body fat (%BF) ⋝ 25 in men and ⋝ 35 in women. Logistic and quantile regressions were employed to examine relationships of interest.

RESULTSOverall, 6.42% of the participants reported short sleep durations (< 6 h/d) while 14.71% reported long (⋝ 9 h/d) sleep durations. Long sleepers (⋝ 9 h/d) represented a greater frequency of women with obesity [odds ratio (OR): 1.30; 95% confidence interval (CI), 1.02-1.67] and high body fat (1.43, 1.04-1.96) than those who slept 7-8 h/d. An association between long sleep times and higher BMI estimations was found across the 10th-75th percentile of the BMI distribution. Among men, long sleepers (⋝ 9 h/d) presented lower risks of developing abdominal obesity compared with individuals who slept 7-8 h/d (OR = 0.79, 95% CI: 0.44-0.99).

CONCLUSIONOur study suggests that long sleep durations are associated with general obesity in Chinese women but reduced waist circumferences in men. Confirmatory studies are needed to determine the heterogeneous association of sleep time and obesity by gender.

Adipose Tissue ; physiology ; Adult ; Asian Continental Ancestry Group ; Body Mass Index ; China ; Female ; Humans ; Male ; Middle Aged ; Rural Population ; Sleep ; physiology ; Surveys and Questionnaires ; Urban Population ; Waist Circumference

PURPOSE: This study sought to determine whether abdominal obesity is a risk factor for impaired fasting glucose (IFG) and hypertriglyceridemia and to verify whether moderate effect of abdominal obesity on the relationship between IFG and hypertriglyceridemia in Korea. MATERIALS AND METHODS: Data from the Korean National Health and Nutrition Examination Survey was used for the analysis. The study population included 5,938 subjects aged 20 year old drawn from non-diabetic participants in a health examination survey. The subjects were classified according to the presence of abdominal obesity based on waist circumference, IFG based on their fasting blood glucose level, and hypertriglyceridemia on their fasting triglyceride. RESULTS: The multivariate-adjusted odds ratios for the occurrence of hypertriglyceridemia were 2.91 in the abdominal obesity group as compared with the nonobesity group and 1.31 in subjects with IFG compared with the normoglycemia controls. Abdominal obesity was found to be positively moderated in the interaction between waist circumference and fasting blood sugar. CONCLUSION: The moderate effect between abdominal obesity and IFG contributes to the development of hypertriglyceridemia in Korea.
Adult ; Aged ; Blood Glucose/*metabolism ; Fasting/blood ; Female ; Humans ; Hypertriglyceridemia/*blood/*pathology ; Logistic Models ; Male ; Middle Aged ; Obesity, Abdominal/*physiopathology ; Triglycerides/blood ; Waist Circumference/physiology ; Young Adult

OBJECTIVESTo explore the optimal threshold values of waist circumference (WC) for detecting cardiovascular (CV) risk factors among Chinese children and adolescents.

METHODSAssociation of WC with CV risk factors was studied among 65,898 children aged 7-18 years whose data were pooled from nine previous studies in China. CV risk factors in this study included hypertension (blood pressure above 95 percentile levels), dyslipidemia (with one or more of the following three indexes: TG > or = 1.7 mmol/L, TC > or = 5.18 mmol/L, and HDL-C < or = 1.04 mmol/L) and elevated glucose level (fasting plasma glucose > or = 5.6 mmol/L). Receive-operating characteristic analysis (ROC) and logistic regression were employed to derive optimal age- and sex-specific waist circumference references for predicting CV risk factors.

RESULTSA slight increasing trend of CV risk factors was observed starting from the 75th percentile of waist circumference in the study population, while a remarkable increasing trend occurred from the 90th percentile. The optimal waist circumference thresholds for predicting high blood pressures were at the 75th percentile for both boys and girls, which was at the 90th percentiles for detecting at least two of the above three CV risk factors. In comparison with children with waist circumference below the 75th percentile, the odds ratio of two CV risk factors doubled among children with waist circumference between the 75th and the 90th percentile, and increased by 6 times among children with waist circumference above the 90th percentile. The trend of high blood pressure increasing with waist circumference remained significant after having been stratified by BMI category.

CONCLUSIONThe 75th and the 90th percentiles of WC are the optimal cut-off points for predicting an increased and a substantially increased risk of CV factors in Chinese children and adolescents, respectively.

Adolescent ; Cardiovascular Diseases ; complications ; epidemiology ; Child ; China ; epidemiology ; Female ; Humans ; Male ; Overweight ; complications ; epidemiology ; Reference Values ; Risk Factors ; Waist Circumference ; physiology

BACKGROUNDObstructive sleep apnea (OSA) syndrome has a negative impact on the health of millions of adolescents and youth. The aim of this study was to evaluate the associations of OSA syndrome with obesity and cardiometabolic risk factors among adolescents and youth at risk for metabolic syndrome (MS).

METHODSA total of 558 subjects aged 14-28 years were recruited from the Beijing Child and Adolescent Metabolic Syndrome Study. Each underwent a 2-h oral glucose tolerance test (OGTT), echocardiography, and liver ultrasonography. Anthropometric measures, blood levels of glucose, lipids, and liver enzymes were assessed. Subjects with high or low risk for OSA were identified by Berlin Questionnaire (BQ).

RESULTSAmong the subjects in obesity, 33.7% of whom were likely to have OSA by BQ. Subjects with high risk for OSA had higher neck and waist circumference and fat mass percentage compared to those with low risk for OSA (P < 0.001). Moreover, significant differences in levels of lipids, glucose after OGTT, and liver enzymes, as well as echocardiographic parameters were found between the two groups with high or low risk for OSA (P < 0.05). The rates of nonalcoholic fatty liver disease (71.0% vs. 24.2%), MS (38.9% vs. 7.0%), and its components in high-risk group were significantly higher than in low-risk group.

CONCLUSIONSThe prevalence of OSA by BQ was high in obese adolescents and youth. A high risk for OSA indicates a high cardiometabolic risk. Mechanisms mediating the observed associations require further investigation.

Adolescent ; Adult ; Beijing ; Female ; Humans ; Male ; Metabolic Syndrome ; complications ; epidemiology ; Obesity ; complications ; epidemiology ; Risk Factors ; Sleep Apnea, Obstructive ; epidemiology ; etiology ; Waist Circumference ; physiology ; Young Adult