Long-Teng Lee

Optimal cut-off values for obesity: Using simple anthropometric indices to predict cardiovascular risk factors in Taiwan

BACKGROUND: The increased health risks associated with obesity have been found to occur in Asians at lower body mass indices (BMIs). To determine the optimal cut-off values for overweight or obesity in Taiwan, we examined the relationships between four anthropometric indices and cardiovascular risk factors.METHODS: The data were collected from four health-screening centers from 1998 to 2000 in Taiwan. Included were 55 563 subjects (26 359 men and 29 204 women, mean age=37.3±10.9 and 37.0±11.1 y, respectively). None had known major systemic diseases or were taking medication. Individual body weight, height, waist circumference (WC), and a series of tests related to cardiovascular risk (blood pressure, fasting plasma glucose, triglycerides, total cholesterol, low- and high-density lipoprotein cholesterol) were assessed and their relationships were examined. Receiver operating characteristic (ROC) analysis was used to find out the optimal cut-off values of various anthropometric indices to predict hypertension, diabetes mellitus and dyslipidemia.RESULTS: Of the four anthropometric indices we studied, waist-to-height ratio (WHtR) in women was found to have the largest areas under the ROC curve (women=0.755, 95% CI 0.748–0.763) relative to at least one risk factor (ie hypertension or diabetes or dyslipidemia). The optimal cut-off values for overweight or obesity from our study in men and women showed that BMIs of 23.6 and 22.1 kg/m2, WCs of 80.5 and 71.5 cm, waist-to-hip ratios (WHpR) of 0.85 and 0.76, and WHtR of 0.48 and 0.45, respectively, may be more appropriate in Taiwan.CONCLUSIONS: WHtR may be a better indicator for screening overweight- or obesity-related CVD risk factors than the other three indexes (BMI, WC and WHpR) in Taiwan. Our study also supported the hypothesis that the cut-off values using BMI and WC to define obesity should be much lower in Taiwan than in Western countries.

Plasma leptin is associated with insulin resistance independent of age, body mass index, fat mass, lipids, and pubertal development in nondiabetic adolescents.

OBJECTIVE: The rising epidemic worldwide in overweight and obese children requires urgent attention. Leptin has been found to be associated with body weight control and possibly affects insulin sensitivity. Since insulin resistance is associated with obesity in adults and possibly in adolescents, we set out to investigate the association of plasma leptin level with various anthropometric indices, body fat mass (FM), lipids, and insulin resistance (IR) index in nondiabetic adolescents.DESIGN: A cross-sectional study from three high schools in Taipei City in Taiwan.SUBJECTS: A total of 402 nondiabetic subjects (162 boys and 240 girls; age range, 10–19 y; mean age, 15.8±1.9 y, and mean body mass index (BMI), 24.8±4.6 kg/m2) were recruited.MEASUREMENTS: The fasting plasma leptin, plasma glucose, insulin, lipids, and anthropometric indices including height, weight, waist (WC) and hip circumferences, and waist-to-hip ratio (WHR) were examined. Total body FM and percentage body fat (FM%) were obtained from dual-energy X-ray absorptiometry. The homeostasis model was applied to estimate the degree of IR.RESULTS: The plasma leptin levels were significantly higher in girls (17.45±10.13 ng/ml) than boys (8.81±6.71 ng/ml, P<0.001). The plasma leptin levels were positively correlated to BMI, WC, WHR, FM, FM%, and triglycerides (TG). The IR index was positively correlated to BMI, WC, WHR, FM, FM%, TG, and leptin. Using the multivariate linear regression models, we found that plasma leptin remains significantly associated with IR index even after adjusting for age, gender, BMI, FM, WC, Tanner stage, and TG.CONCLUSION: Plasma leptin was associated with IR index independent of age, gender, BMI, FM, WC, Tanner stage, and TG. Plasma leptin levels in adolescents could be a predictor for the development of the metabolic syndrome disorders and cardiovascular diseases.

Four anthropometric indices and cardiovascular risk factors in Taiwan.

OBJECTIVE: To examine the relationships between four anthropometric measurements and cardiovascular risk factors in Taiwan.DESIGN: The data was collected from four nationwide health screen centers in Taiwan from 1998 to 1999.SUBJECTS: A total of 38 556 subjects: 18 280 men and 20 276 women, mean age=37.0±11.1 y. None had any known major systemic diseases or were currently on medication.MEASUREMENTS: Individual body weight, height, waist circumference (WC), and cardiovascular risk factors (blood pressure, fasting plasma glucose, triglycerides, total cholesterol level, low-density and high-density-lipoprotein cholesterol level) were assessed and their relationships were examined.RESULTS: In both sexes, with increasing body mass index (BMI), WC, WHpR (waist-to-hip ratio) and WHtR (waist-to-height ratio), there were significantly higher risks of hypertension, impaired fasting glucose, diabetes and dyslipidemia (P<0.001) in almost all age groups. In the age groups older than 65, however, the relationships were statistically inconsistent.CONCLUSIONS: In Taiwan, the four anthropometric indexes (BMI, WC, WHpR, WHtR) are closely related to cardiovascular risk factors.

Sarcopenic obesity is closely associated with metabolic syndrome

OBJECTIVES Obesity is a risk factor for metabolic syndrome (MetS). We aimed to investigate whether sarcopenic obesity (SO) was associated with MetS. METHODS A total of 600 community-dwelling males and females aged 63.6 ± 10.1 years in Northern Taiwan were enrolled in this study. Sarcopenia was defined by the percentage of total skeletal mass (total skeletal muscle mass (kg)/weight (kg) x 100). Cut-offs were established at <37% in men and <27.6% in women using the bioelectrical impedance analysis (BIA) method. Obesity was defined as body mass index (BMI) ≥25 kg/m(2). MetS was defined by the consensus of National Cholesterol Education Program-Adult Treatment Panel III modified for Asians. The association between MetS and SO was examined using multivariate logistic regression analyses after controlling potential confounders. RESULTS The SO group demonstrated a higher risk for MetS (odds ratio [OR] 11.59 [95% confidence interval [CI] 6.72-19.98]) than the obese group (7.53 [4.01-14.14]) and sarcopenic group (1.98 [1.25-3.16]). The individual components including waist circumference, serum triglycerides, high-density lipoprotein cholesterol (HDL-C), and fasting serum glucose were independently associated with SO. CONCLUSION SO is a major risk factor for MetS. The BIA method and BMI can easily identify subjects at high risk for MetS. The underlying mechanism for the relationship between SO and MetS warrants further research.

Insulin resistance, obesity, and metabolic syndrome among non-diabetic pre- and post-menopausal women in North Taiwan

Objective:To investigate the relationship between the metabolic syndrome and its related factors among non-diabetic pre- and post-menopausal women in North Taiwan.Design:A cross-sectional study in a medical center in North Taiwan.Subjects:Five hundred and ninety-four, non-diabetic middle-aged women (age range=40–64 years, mean=48.9±5.4 years) were recruited.Measurements:The fasting plasma glucose, insulin, lipids levels and anthropometric indices were measured. The homeostasis model assessment was applied to estimate the degree of insulin resistance (HOMA-IR). Metabolic syndrome was defined by using the National Cholesterol Education Panel (NCEP) criteria and modified NCEP criteria (waist circumference >80 cm).Results:The prevalence of metabolic syndrome was 6.2% using NCEP criteria, and 8.9% using modified NCEP criteria. Post-menopausal women had a higher prevalence of metabolic syndrome and its individual components compared to pre-menopausal women except hyperglycemia and low HDL-C. In multiple logistic regression analysis with adjustment for age and menopausal status, both BMI and HOMA-IR were independently associated with the metabolic syndrome.Conclusion:The prevalence of metabolic syndrome was higher in post-menopausal than pre-menopausal women. Both obesity and insulin resistance may play an important role in the development of metabolic syndrome among the middle-aged women in North Taiwan.

Serum selenium concentration is associated with metabolic factors in the elderly: a cross-sectional study

BackgroundSelenium is an essential micronutrient known for its antioxidant function. However, the association of serum selenium with lipid profiles and fasting glucose are inconsistent in populations with average intake of selenium. Furthermore, there were few studies conducted specifically for the elderly. This study examined the relationship of serum selenium concentration with serum lipids and fasting glucose in the Taiwanese elderly population.MethodsThis was a cross-sectional study of 200 males and females aged 65-85 years (mean 71.5 ± 4.6 years) from Taipei, Taiwan. Serum selenium was measured by inductively coupled plasma-mass spectrometer. The association between serum selenium and metabolic factors was examined using a multivariate linear regression analysis after controlling several confounders.ResultsThe mean serum selenium concentration was 1.14 μmol/L, without significant difference between sexes. Total cholesterol, triglycerides, and LDL cholesterol increased significantly with serum selenium concentration (P < 0.001, P < 0.05 and P < 0.001, respectively) after adjusting for age, gender, anthropometric indices, lifestyle factors, and cardio-vascular risk factors in several linear regression models. Furthermore, there was a significantly positive association between serum selenium and serum fasting glucose concentrations (P < 0.05).ConclusionsTotal cholesterol, triglycerides, and LDL cholesterol, and fasting serum glucose concentrations increased significantly with serum selenium concentration in the Taiwanese elderly. The underlying mechanism warrants further research.

Obesity and hepatitis B infection are associated with increased risk of metabolic syndrome in university freshmen

Objective:To investigate the prevalence of metabolic syndrome and its associated risk factors in a cohort of university freshmen.Design:A cross-sectional study in a university health center in North Taiwan.Subjects:A total of 8226 students (mean age: 19.2±2.3 years) receiving pre-entrance health examinations and lifestyle questionnaires during the 2005–2006 academic year were recruited.Measurements:A fasting plasma glucose, lipids, uric acid and hepatitis B serology were measured for each subject. The prevalence of metabolic syndrome and its individual components were examined using the America Heart Association and National Heart Lung Blood Institute criteria. The risk factors for metabolic syndrome were identified using a multivariate logistic regression analysis.Results:The prevalence of overweight, obesity and metabolic syndrome was 12.7% (17.0% in men and 7.6% in women), 13.0% (18.4% in men and 6.4% in women) and 4.6% (6.4% in men and 2.4% in women). The risk for metabolic syndrome increased with an increase of body mass index and plasma uric acid level, and decreased with the vigorous physical activity and current alcohol drinking. Furthermore, as compared to subjects with seroprotective titers from hepatitis B vaccination (anti-HBs(+) and anti-HBc(−)), those without protective titers of anti-HBs after vaccination or without hepatitis B infection (anti-HBs(−) and anti-HBc(−)) had 34% higher risk for metabolic syndrome, and those with natural infection of hepatitis B (anti-HBc(+)) had 58% higher risk for metabolic syndrome.Conclusions:Overweight, obesity and metabolic syndrome were more common among men than women in university freshmen. Hepatitis B vaccination with anti-HBs(+) was associated with a lower risk of metabolic syndrome as compared to anti-HBs(−). However, hepatitis B infection presented with anti-HBc(+) was associated with a higher risk of metabolic syndrome. The interplay between hepatitis B infection, hepatitis B vaccination and metabolic syndrome needs further investigation.

All-cause and Cardiovascular Disease Mortality Increased With Metabolic Syndrome in Taiwanese

Objective: This study aimed to investigate the relationship between mortality and metabolic syndrome using the America Heart Association/National Heart Lung Blood Institute (AHA/NHLBI) and International Diabetes Federation (IDF) definitions in a Taiwanese cohort.

Age-period-cohort analysis of hepatocellular carcinoma mortality in Taiwan, 1976-2005.

PURPOSE Hepatocellular carcinoma (HCC) is one of the most common malignant primary liver tumors worldwide. A previous study showed a decline in pediatric HCC in Taiwan after the universal vaccination program was initiated in 1984. We investigated whether the recent change in HCC mortality in Taiwan represented a short-term fluctuation or an emerging long-term decline trend. METHODS An age-period-cohort analysis was conducted to show HCC mortality trends between 1976 and 2005. A total of 121,643 HCC mortality cases (92,926 males and 28,717 females) of individuals older than 40 years of age was used in the analyses. RESULTS Results indicate an increasing secular trend in HCC mortality over the last three decades in people aged 60 years and above. In the age group of >85 years old, the mortality rate for males and females was 7.47 (95% confidence interval [95% CI]: 6.24-8.94) and 25.0 (95% CI: 15.5-40.2) times greater than in the youngest age group (40-44), respectively. The relative risk of dying from HCC in the period 2001-2005 was 1.36 (95% CI: 1.23-1.50) for males compared to the 1976-1980 time period, and 1.42 (95% CI: 1.17-1.72) for females compared to the 1986-1990 time period. A strong birth-cohort effect was also found. Individuals born around 1936 had the highest risk of dying from HCC. CONCLUSION These findings imply that important determinants of HCC may occur early in life, with their effects only becoming apparent much later.

Family experience with difficult decisions in end-of-life care

The difficult decisions encountered by family caregivers in the process of care for patients with terminal cancer are seldom studied. Investigating their experiences with difficult decisions may help relieve their psychological distress. The purpose of this study was to determine the frequency and difficulty of decisions experienced in end‐of‐life care and to identify related factors.