Obesity in South Africa: The South African Demographic and Health Survey

Objectives: To ascertain the anthropometric profile and determinants of obesity in South Africans who participated in the Demographic and Health Survey in 1998. Research Methods and Procedures: A sample of 13,089 men and women (age, ≥15 years) were randomly selected and then stratified by province and urban and nonurban areas. Height, weight, mid-upper arm circumference, and waist and hip circumference were measured. Body mass index (BMI) was used as an indicator of obesity, and the waist/hip ratio (WHR) was used as an indicator of abdominal obesity. Multivariate regression identified sociodemographic predictors of BMI and waist circumference in the data. Results: Mean BMI values for men and women were 22.9 kg/m² and 27.1 kg/m², respectively. For men, 29.2% were overweight or obese (≥25 kg/m²) and 9.2% had abdominal obesity (WHR ≥1.0), whereas 56.6% of women were overweight or obese and 42% had abdominal obesity (WHR >0.85). Underweight (BMI <18.5 kg/m²) was found in 12.2% of men and 5.6% of women. For men, 19% of the variation of BMI and 34% of the variation in waist circumference could be explained by age, level of education, population group, and area of residence. For women, these variables explained 16% of the variation of BMI and 24% of the variation in waist circumference. Obesity increased with age, and higher levels of obesity were found in urban African women. Discussion: Overnutrition is prevalent among adult South Africans, particularly women. Determinants of overnutrition include age, level of education, ethnicity, and area of residence.     

First nationwide survey of prevalence of overweight, underweight, and abdominal obesity in Iranian adults

Objective: The goal was to estimate the prevalence of overweight, obesity, underweight, and abdominal obesity among the adult population of Iran. Research Methods and Procedures: A nationwide cross‐sectional survey was conducted from December 2004 to February 2005. The selection was conducted by stratified probability cluster sampling through household family members in Iran. Weight, height, and waist circumference (WC) of 89,404 men and women 15 to 65 years of age (mean, 39.2 years) were measured. The criteria for underweight, normal‐weight, overweight, and Class I, II, and III obesity were BMI <18.5, 18.5 to 24.9, 25 to 29.9, 30 to 34.9, 35 to 39.9, and ≥40 (kg/m²), respectively. Abdominal obesity was defined as WC ≥102 cm in men and ≥88 cm in women. Results: The age‐adjusted means for BMI and WC were 24.6 kg/m² in men and 26.5 kg/m² in women and 86.6 cm in men and 89.6 cm in women, respectively. The age‐adjusted prevalence of overweight or obesity (BMI ≥25) was 42.8% in men and 57.0% in women; 11.1% of men and 25.2% of women were obese (BMI ≥30), while 6.3% of men and 5.2% of women were underweight. Age, low physical activity, low educational attainment, marriage, and residence in urban areas were strongly associated with obesity. Abdominal obesity was more common among women than men (54.5% vs. 12.9%) and greater with older age. Discussion: Excess body weight appears to be common in Iran. More women than men present with overweight and abdominal obesity. Prevention and treatment strategies are urgently needed to address the health burden of obesity.     

Prevalence and risk factors of overweight and obesity in China

Objective: To examine the prevalence and risk factors of overweight and obesity in China. Research Methods and Procedures: A cross‐sectional survey was conducted in a nationally representative sample of 15,540 Chinese adults in 2000–2001. Body weight, height, and waist circumference were measured by trained observers. Overweight and obesity were defined according to the World Health Organization classification. Central obesity was defined according to guidelines of the International Diabetes Federation. Results: Mean BMI and waist circumference were 23.1 kg/m² and 79.6 cm, respectively, for men and 23.5 kg/m² and 77.2 cm, respectively, for women. The prevalences of overweight and obesity were 24.1% and 2.8% in men and 26.1% and 5.0% in women, respectively. The prevalence of central obesity was 16.1% in men and 37.6% in women. The prevalences of overweight, obesity, and central obesity were higher among residents in northern China compared with their counterparts in southern China and among those in urban areas compared with those in rural areas. Lifestyle factors were the most important risk factors to explain the differences in overweight and central obesity between northern and southern residents. Among women, lifestyle and diet were the most important risk factors to explain the differences between urban and rural residents, whereas socioeconomic status, lifestyle, and diet were all important among men. Discussion: Our study indicates that overweight and obesity have become important public health problems in China. Environmental risk factors may be the main reason for regional differences in the prevalence of overweight and obesity in China.     

Prevalence and Covariates of Obesity in Lebanon: Findings from the First Epidemiological Study

Objective: To estimate the prevalence of overweight and obesity and examine associated covariates in the Lebanese population. Research Methods and Procedures: A cross‐sectional survey of a representative sample of 2104 individuals, 3 years of age and older. Anthropometric measurements and dietary assessments were conducted following standard methods and techniques. Overweight and obesity (classes I to III) were defined according to internationally standardized criteria for classification of BMI. Results: For children 3 to 19 years of age, prevalence rates of overweight and obesity were higher overall for boys than girls (22.5% vs. 16.1% and 7.5% vs. 3.2%, respectively). For adult men and women (age ≥ 20 years), the prevalence of overweight was 57.7% and 49.4%, respectively. In contrast, obesity (BMI ≥ 30 kg/m²) was higher overall among women (18.8%) than men (14.3%), a trend that became more evident with increasing obesity class. BMI, percentage of body fat, and waist circumference increased to middle age and declined thereafter. Whereas lack of exercise associated significantly with obesity among children, obesity in older adults was more prevalent among the least educated, nonsmokers, and those reporting a family history of obesity. Discussion: The results from this national population‐based study in Lebanon show high prevalence rates of overweight and obesity comparable with those observed in developed countries such as the United States. While further studies are needed to examine the underlying social and cultural factors associated with lifestyle and nutritional habits, now is the time to institute multicomponent interventions promoting physical activity and weight control nationwide.     

Prevalence of Overweight and Obesity and Their Associations with Socioeconomic Status in a Rural Han Chinese Adult Population

Background

The purpose of this study is to describe the prevalence of overweight, general obesity, and abdominal obesity and examine their associations with socioeconomic status in a rural Chinese adult population.

Methods

This cross-sectional study was performed on 15,236 participants ≥ 35 years of age (6,313 men [41.4%] and 8,923 women [58.6%]). Each participant’s weight, height, waist circumference (WC), and hipline circumference (HC) were measured, and demographic and socioeconomic data were collected using questionnaires.

Results

The mean body mass index (BMI) values were 23.31 ± 2.96 and 23.89 ± 3.23 kg m^-2 and the mean WC values were 79.13 ± 8.43 and 79.54 ± 8.27 cm for men and women, respectively. The age-standardized prevalence rates of overweight (BMI ≥ 24.0 kg m^-2), general obesity (BMI ≥ 28.0 kg m^-2), and abdominal obesity (WC ≥ 85 cm for men and ≥ 80 cm for women) were 32.0%, 6.7%, and 27.0% for men and 35.1%, 9.7%, and 48.3% for women, respectively. All gender differences were statistically significant (p < 0.001). In addition, the age-specific prevalence rates of general and abdominal obesity slowly decreased among men but sharply increased among women as age increased (p < 0.001). In subsequent logistic regression analysis, educational level was negatively associated with both general obesity and abdominal obesity among women but positively associated with abdominal obesity among men. No significant correlation was found between obesity and income.

Conclusions

These results suggest a high prevalence of obesity which might differ by gender and age, and an inverse association among women and a mixed association among men noted between education and obesity in our locality. Preventive and therapeutic programs are warranted to control this serious public health problem. The gender-specific characteristics of populations at high-risk of developing obesity should be taken into consideration when designing interventional programs.     

Central obesity as a risk factor for prostatic hyperplasia

Objective: Obesity‐related metabolic diseases may influence prostatic hyperplasia. This study examined the impact of obesity on prostate volume in men without overt obesity‐related metabolic diseases. Research Methods and Procedures: We recruited 146 men over the age of 40 years who did not have overt obesity‐related diseases, such as diabetes, impaired fasting glucose, hypertension, or dyslipidemia. Transrectal ultrasonography was performed on all subjects. The subjects were divided into three groups according to their BMI: normal (18.5 to 22.9 kg/m²), overweight (23 to 24.9 kg/m²), and obese (≥25 kg/m²), and two groups according to their waist circumference: normal waist (≤90 cm) and central obesity (>90 cm). The classification of the subgroups was based on the Asia‐Pacific criteria of obesity. We compared the prostate volume among subgroups and assessed factors related to prostatic hyperplasia. Results: Mean prostate volume was 18.8 ± 5.0, 21.8 ± 7.2, and 21.8 ± 5.6 mL in the normal, overweight, and obese groups, respectively, and was 20.0 ± 5.9 and 23.7 ± 5.3 mL in the normal waist and central obesity group, respectively. Prostate volume was significantly greater in the obese group than in the normal group (P = 0.03) and in the central obesity group compared with the normal waist group (P = 0.002). Prostate volume was positively correlated with BMI and waist circumference after adjustment for age. After adjusting for confounding factors, central obesity was an independent factor affecting prostatic hyperplasia, which was defined as a prostate volume >20 mL (odds ratio = 3.37, p = 0.037). Relative to men with both low BMI (18.5 to 22.9 kg/m²) and normal waist circumference, those with high BMI (≥25 kg/m²) and central obesity were at significantly increased risk of prostatic hyperplasia (odds ratio = 4.88, p = 0.008). However, those with high BMI (≥25 kg/m²) and normal waist circumference were not at significantly increased risk. Discussion: Prostate volume was greater in the obese and central obesity groups than in the normal group after patients with overt obesity‐related metabolic diseases were excluded. Although both BMI and waist circumference were positively correlated with prostate volume, central obesity was the only independent factor affecting prostate hyperplasia. We suggest that central obesity is an important risk factor for prostatic hyperplasia.     

Prevalence of obesity and the relationship between the body mass index and body fat: cross-sectional, population-based data

Background

Anthropometric measures such as the body mass index (BMI) and waist circumference are widely used as convenient indices of adiposity, yet there are limitations in their estimates of body fat. We aimed to determine the prevalence of obesity using criteria based on the BMI and waist circumference, and to examine the relationship between the BMI and body fat.

Methodology/Principal Findings

This population-based, cross-sectional study was conducted as part of the Geelong Osteoporosis Study. A random sample of 1,467 men and 1,076 women aged 20–96 years was assessed 2001–2008. Overweight and obesity were identified according to BMI (overweight 25.0–29.9 kg/m²; obesity ≥30.0 kg/m²) and waist circumference (overweight men 94.0–101.9 cm; women 80.0–87.9 cm; obesity men ≥102.0 cm, women ≥88.0 cm); body fat mass was assessed using dual energy X-ray absorptiometry; height and weight were measured and lifestyle factors documented by self-report. According to the BMI, 45.1% (95%CI 42.4–47.9) of men and 30.2% (95%CI 27.4–33.0) of women were overweight and a further 20.2% (95%CI 18.0–22.4) of men and 28.6% (95%CI 25.8–31.3) of women were obese. Using waist circumference, 27.5% (95%CI 25.1–30.0) of men and 23.3% (95%CI 20.8–25.9) of women were overweight, and 29.3% (95%CI 26.9–31.7) of men and 44.1% (95%CI 41.2–47.1) of women, obese. Both criteria indicate that approximately 60% of the population exceeded recommended thresholds for healthy body habitus. There was no consistent pattern apparent between BMI and energy intake. Compared with women, BMI overestimated adiposity in men, whose excess weight was largely attributable to muscular body builds and greater bone mass. BMI also underestimated adiposity in the elderly. Regression models including gender, age and BMI explained 0.825 of the variance in percent body fat.

Conclusions/Significance

As the BMI does not account for differences in body composition, we suggest that gender- and age-specific thresholds should be considered when the BMI is used to indicate adiposity.     

Trends in overweight and obesity in Chinese adults: between 1991 and 1999-2000

Objective: The aim of this study was to evaluate trends in BMI and the prevalence of overweight (BMI ≥ 25 kg/m²) and obesity (BMI ≥ 30 kg/m²) between 1991 and 1999–2000 among Chinese adults. Methods and Procedures: In this study, two population‐based samples of Chinese adults aged between 45 and 79 years (n = 7,858 during each period), and comparable in the distributions of age, gender, degree of urbanization, and region (North/South) were used. Height and weight were measured using identical procedures at each period, and BMI was calculated as weight (in kilogram) divided by height (in square meter). Results: From 1991 to 1999–2000, the mean BMI increased from 21.8 to 23.4 kg/m² among men and from 21.8 to 23.5 kg/m² among women (each P < 0.001). Among men, the prevalence of overweight and obesity increased from 9.6 and 0.6%, respectively, in 1991 to 20.0 and 3.0%, respectively, in 1999–2000 (each P < 0.001). Among women, the prevalence of overweight and obesity increased from 14.5 and 1.8%, respectively, in 1991 to 26.5 and 5.2%, respectively, in 1999–2000 (each P < 0.001). The prevalence of overweight and obesity increased in all age groups, in rural and urban areas, and in North and South China, with greater relative increases in obesity among older age groups, South China, and rural areas (P interaction < 0.05). Discussion: Overweight and obesity increased tremendously during the 1990s in China. These data underscore the need for national programs in weight maintenance and reduction, to prevent obesity‐related outcomes in China.     

Prevalence of Obesity and Associated Risk Factors in a Turkish Population (Trabzon City,Turkey)

Objective: To estimate the prevalence of overweight and obesity (general and central) in the Trabzon Region and its associations with demographic factors (age, sex, marital status, reproductive history in women, and level of education), socioeconomic factors (household income and occupation), family history of selected medical conditions (diabetes, hypertension, and obesity), lifestyle factors (smoking habits, physical activity, and alcohol consumption), and hypertension in the adult population. Research Methods and Procedures: A sample of households was systematically selected from the central province of Trabzon and its five towns, namely, Sürmene, Vakfikebir, Maçka, Hayrat, and Tonya. A total of 5016 subjects (2728 women and 2288 men) were included in the study. Individuals more than 20 years old were selected from their family health cards. Demographic factors, socioeconomic factors, family history of selected medical conditions, and lifestyle factors were obtained for all participants. Systolic blood pressure and diastolic blood pressure levels were measured for all subjects. Study procedures were carried out in the local health centers in each town over an 8‐month period. Obesity was defined as BMI ≥ 30 kg/m² and overweight as BMI = 25.0 to 29.9 kg/m². Results: The prevalence of obesity was 23.5%: 29.4% in women and 16.5% in men. The combined prevalence of both overweight and obesity was 60.3%. The prevalence of abdominal obesity was 29.4%: 38.9% among women and 18.1% among men. The prevalence of obesity increased with age, being highest in the 60‐ to 69‐year‐old age group (40.8%) but lower again in the 70+ age group. Obesity was associated positively with marital status, parity, cessation of cigarette smoking, alcohol consumption, and household income and inversely with level of education, cigarette use, and physical activity. Also, obesity was associated positively with hypertension. Discussion: In the Trabzon Region, 60.3% of the adult population presents with some excess weight. Obesity is a major public health problem that requires generalized interventions to prevent it among the adult population.     

Overweight,Obesity, and Binge Eating in a Non‐clinical Sample of Five Brazilian Cities

Objective: To investigate the relationship between obesity/overweight and binge eating episodes (BEEs) in a large nonclinical population. Research Methods and Procedures: Consumers at shopping centers in five Brazilian cities (N = 2858) who participated in an overweight prevention program were interviewed and had weight and height measured to calculate BMI. Results: Prevalence of overweight (BMI = 25 to 29.9 kg/m²) was 46.6% for men and 36.6% for women. Obesity (BMI ≥ 30 kg/m²) was about two‐thirds of the prevalence of overweight. BEEs (subjects who binged one or more times per week over the last 3 months) in normal‐weight individuals was 1.4% for men and 3.9% for women, whereas in overweight/obese, these prevalences were 6.5% and 5.5%, respectively (p < 0.01). After adjustment for age, socioeconomic variables, and childhood obesity, those who reported BEEs had an odds ratio of being overweight/obese of 3.31 (95% confidence interval: 1.11 to 9.85) for men and 1.73 (95% confidence interval: 1.05 to 2.84) for women. Discussion: These findings indicate a strong association between episodes of binge eating and overweight/obesity, mainly among men.     

Total and Central Obesity among Elderly Hispanics and the Association with Type 2 Diabetes

Objective: To report the prevalence of total and central obesity in a representative sample of Puerto Rican and Dominican elders in Massachusetts, to compare them with a neighborhood‐based group of non‐Hispanic white elders, and to examine associations of obesity indices with the presence of type 2 diabetes. Research Methods and Procedures: We examined the prevalence of overweight, obesity, and central obesity in 596 Hispanics of Caribbean origin, ages 60 to 92 years, and 239 non‐Hispanic whites, and tested linear and logistic regression models to determine associations among body mass index (BMI), waist circumference (WC), and diabetes. Results: Obesity (BMI ≥ 30 kg/m²) was prevalent among all ethnic groups, ranging from 17% to 29% for Dominican and Puerto Rican men, respectively, and from 29% to 40% for non‐Hispanic white and Dominican women, respectively. These differences were not statistically significant. Among Hispanic men and women, diabetes was prevalent across all BMI and WC categories but tended to be greatest among those with BMI of 25 to 29 kg/m² (41% to 43%). In contrast, diabetes was most prevalent in the obese group (36% to 45%) of non‐Hispanic whites. Both BMI and WC were associated with the presence of diabetes, but the coefficients were greater for non‐Hispanic whites than for Hispanics. Discussion: Caribbean Hispanics and non‐Hispanic whites living in the same Massachusetts localities had high prevalences of overweight and obesity. Total and central obesity exerted a differential effect on the presence of diabetes among ethnic groups; for Hispanics, diabetes was prevalent even among non‐obese individuals, whereas for non‐Hispanic white women, the prevalence of diabetes was strongly associated with total and central obesity. Additional research is needed to investigate the factors associated with the differential effect of obesity on the prevalence of type 2 diabetes among Hispanic and non‐Hispanic white elders.     

Prevalence of Overweight and Obesity and Weight Loss Practice among Beijing Adults, 2011

Objective

This study aims to determine the up-to-date prevalence of overweight and obesity, the distributions of body weight perception and weight loss practice in Beijing adults.

Methods

A cross-sectional study was conducted in 2011. A total of 2563 men and 4088 women aged 18–79 years from the general population were included. Data were obtained from questionnaire and physical examination.

Results

The prevalence of overweight (BMI 24–27.9 kg/m²) and obesity (BMI≥28 kg/m²) was 42.1% and 20.3% in men and 35.6% and 17.1% in women, respectively. Age was inversely associated with overweight in both sexes, and obesity in women. Education level was negatively associated with overweight and obesity in women but not in men. Only 49.1% men and 58.3% women had a correct perception of their body weight. Underestimation of body weight was more common than overestimation, especially in men, the older people, and those with low education level. The percentage of taking action to lose weight was inversely associated with men and old age, and positively associated with higher education level, higher BMI, and self-perception as “fat” (OR = 3.78 in men, OR = 2.91 in women). Only 26.1% of overweight/obese individuals took action to lose weight. The top two weight loss practices were to reduce the amount of food intake and exercise.

Conclusion

Overweight and obesity were highly prevalent with high incorrect body weight perceptions in the general adult population in Beijing. Weight loss practice was poor in overweight and obese individuals. Actions at multiple levels are needed to slow or control this overweight and obesity epidemic.     

Associations of leukocyte telomere length with body anthropometric indices and weight change in chinese women

Objective: This study evaluated associations of telomere length with various anthropometric indices of general and abdominal obesity, as well as weight change. Design and Methods: The study included 2,912 Chinese women aged 40‐70 years. Monochrome multiplex quantitative polymerase chain reaction was applied to measure relative telomere length. Results: Telomere length was inversely associated with body mass index (BMI), waist circumference, waist‐to‐height ratio, weight, and hip circumference (P_trend = 0.005, 0.004, 0.004, 0.010, and 0.026, respectively), but not waist‐to‐hip ratio (P_trend = 0.116) or height (P_trend = 0.675). Weight change since age 50 was further evaluated among women over age 55. Women who maintained their weight within ±5% since age 50, particularly within a normal range (BMI = 18.5‐24.9 kg/m²), or reduced their weight from overweight (BMI = 25‐29.9 kg/m²) or obesity (BMI ≥30 kg/m²) to normal range, had a longer mean of current telomere length than women who gained weight since age 50 (P_trend = 0.025), particularly those who stayed in obesity or gained weight from normal range or overweight to obesity (P = 0.023). Conclusion: Our findings show that telomere shortening is associated with obesity and that maintaining body weight within a normal range helps maintain telomere length.     

Evolution of the Prevalence of Obesity in the Workers of a General Hospital in Mexico

Objective: The objective of this study was to compare the prevalence of overweight and obesity in the first Prevalencia de factores de nesso cardiovascular en Trabajadores survey (1994) with the prevalence of overweight and obesity observed in the second survey (1996). Research Methods and Procedures: For both surveys the following individual data were collected: age, sex, weight, height, and body mass index (BMI). The 1994 survey included 2383 people and the 1996 survey included 2759 people. The degree of BMI was classified according to the current World Health Organization definitions. The population was divided by gender and age group, and the prevalence of each level of overweight was calculated. Additionally, the prevalence of different cutoff levels of BMI was calculated by gender and age groups. Results: The global prevalence of age‐adjusted overweight increased from 26.91% to 37.45%. This increase was observed in both genders but the men had a higher increase from 24.51% to 40.21%. Overweight was more frequent in men than in women in all age groups. Male overweight prevalence was higher in the 40‐ to 59‐year‐old group and ≥60‐year‐old group. Female overweight prevalence was predominant in the 30‐ to 39‐year‐old, 40‐ to 49‐year‐old, and 50‐ to 59‐year‐old groups. Global prevalence of obesity (≥30 kg/m²) changed from 13.8% to 17.2%. Particularly, global prevalence of obesity class I increased from 9.66% to 12.6%; in men this figure increased from 9.04% to 13.05% and in women from 9.9% to 12.71%. Discussion: Prevalence of overweight and obesity has increased significantly in the studied population. It is necessary to implement lifestyle modifications to prevent the increase of prevalence of overweight and obesity.     

Overall and central obesity and risk of type 2 diabetes in U.S. black women

Objective: Obesity has risen to epidemic proportions in the United States, leading to an emerging epidemic of type 2 diabetes. African‐American women are disproportionately affected by both conditions. While an association of overall obesity with increasing risk of diabetes has been documented in black women, the effect of fat distribution, specifically abdominal obesity, has not been studied. We examined the association of BMI, abdominal obesity, and weight gain with risk of type 2 diabetes. Research Methods and Procedures: During eight years of follow‐up of 49,766 women from the Black Women's Health Study, 2472 incident cases of diabetes occurred. Cox proportional hazard models were used to estimate incidence rate ratios (IRRs), with control for age, physical activity, family history of diabetes, cigarette smoking, years of education, and time period of data collection. Results: Sixty‐one percent of participants had a BMI ≥25 kg/m² (WHO definition of overweight). Compared with a BMI of <23 kg/m², the IRR for a BMI of >45 kg/m² was 23 (95% confidence interval, 17.0 to 31.0). The IRR for the highest quintile of waist‐to‐hip ratio relative to the lowest was 2.3 (95% confidence interval, 2.0 to 2.7) after control for BMI. Furthermore, at every level of BMI, an increased risk was observed for high waist‐to‐hip ratio relative to low. Discussion: Central obesity, as well as overall obesity, is a strong risk factor for diabetes in African‐American women. Efforts to reduce the prevalence of obesity in African‐American women are of paramount importance.     

Hypocretin Deficiency in Narcoleptic Humans Is Associated with Abdominal Obesity

Objective: To determine the prevalence of obesity among patients with narcolepsy, to estimate associated long‐term health risks on the basis of waist circumference, and to distinguish the impact of hypocretin deficiency from that of increased daytime sleepiness (i.e., reduced physical activity) on these anthropometric measures. Research Methods and Procedures: A cross‐sectional, case‐control study was conducted. Patients with narcolepsy (n = 138) or idiopathic hypersomnia (IH) (n = 33) were included. Age‐matched, healthy members of the Dutch population (Monitoring Project on Risk Factors for Chronic Diseases and Doetinchem Project; n = 10, 526) were used as controls. BMI and waist circumference were determined. Results: Obesity (BMI ≥ 30 kg/m²) and overweight (BMI 25 to 30 kg/m²) occurred more often among narcolepsy patients [prevalence: 33% (narcoleptics) vs. 12.5% (controls) and 43% (narcoleptics) vs. 36% (controls), respectively; both p < 0.05]. Narcoleptics had a larger waist circumference (mean difference 5 ± 1.4 cm, p < 0.001). The BMI of patients with IH was significantly lower than that of narcolepsy patients (25.6 ± 3.6 vs. 28.5 ± 5.4 kg/m²; p = 0.004). Discussion: Overweight and obesity occur frequently in patients with narcolepsy. Moreover, these patients have an increased waist circumference, indicating excess fat storage in abdominal depots. The fact that patients with IH had a lower BMI than narcoleptics supports the notion that excessive daytime sleepiness (i.e., inactivity) cannot account for excess body fat in narcoleptic patients.     

Obesity in the Elderly and Its Relationship with Cardiovascular Risk Factors in Taiwan**

Objectives: The obese elderly are at increased risk of mortality, morbidity, and functional disability. In this study, we examined the prevalence of obesity and relationship between various anthropometric indices (AI) and cardiovascular disease (CVD) risk factors in the elderly. Research Methods and Procedures: A stratified multistage clustered sampling scheme was used in the Elderly Nutrition and Health Survey in Taiwan during 1999 to 2000. 2432 non‐institutionalized subjects (age, 72.8 ± 9.4 years; BMI, 23.6 ± 6.4 kg/m²) were recruited. The receiver operating characteristic analysis was used to compare predictive validity of CVD risk factors among various AI, including BMI, waist circumference (WC), and waist‐to‐hip ratio (WHR). Results: The prevalence of obesity was 29.0% in men and 36.8% in women by obesity criteria for Asians (BMI ≥ 25 kg/m²) and 13.3% in men and 21.0% in women by the Taiwanese definition (BMI ≥ 27 kg/m²). Odds ratios of acquiring various CVD risk factors increased significantly with increment of WC, WHR, and BMI. The areas under the curve predicting metabolic syndrome were all <0.8. The cut‐off values of WC corresponding to the highest sensitivity and the highest specificity in predicting various CVD risk factors were 86.2–88.0 cm in men and 82.0–84.0 cm in women, respectively. Discussion: Obesity was prevalent in the Taiwanese elderly. WC was related to CVD risk factors to a greater extent than BMI and WHR. However, none of them alone was a good screening tool for CVD risk factors. Therefore, how to apply AI prudently to screen elderly for CVD risk factors needs further research.     

Effects of Obesity and Body Fat Distribution on Lipids and Lipoproteins in Nondiabetic American Indians: The Strong Heart Study

Objectives: To examine the relationship between obesity and lipoprotein profiles and compare the effects of total obesity and central adiposity on lipids/lipoproteins in American Indians. Research Methods and Procedures: Participants were 773 nondiabetic American Indian women and 739 men aged 45 to 74 years participating in the Strong Heart Study. Total obesity was estimated using body mass index (BMI). Central obesity was measured as waist circumference. Lipoprotein measures included triglycerides, high‐density lipoprotei in (HDL) cholesterol, low‐density lipoprotein (LDL) cholesterol, apolipoprotein AI (apoAI), and apolipoprotein B (apoB). Partial and canonical correlation analyses were used to examine the associations between obesity and lipids/lipoproteins. Results: Women were more obese than men in Arizona (median BMI 32.1 vs. 29.2 kg/m²) and South Dakota and North Dakota (28.3 vs. 28.0 kg/m²), but there was no sex difference in waist circumference. Men had higher apoB and lower apoAI levels than did women. In women, when adjusted for center, gender, and age, BMI was significantly related to HDL cholesterol (r = ?0.24, p < 0.001). There was a significant but weak relation with apoAI (r = ?0.14 p < 0.001). Waist circumference was positively related to triglycerides (r = 0.14 p < 0.001) and negatively related to HDL cholesterol (r = ?0.23, p < 0.001) and apoAI (r = ?0.13, p < 0.001). In men, BMI was positively correlated with triglycerides (r = 0.30, p < 0.001) and negatively correlated with HDL cholesterol (r = ?0.35, p < 0.001) and apoAI (r = ?0.23, p < 0.001). Triglycerides increased with waist circumference (r = 0.30, p < 0.001) and HDL cholesterol decreased with waist circumference (r = ?0.36 p < 0.001). In both women and men there was an inverted U‐shaped relationship between obesity and waist with LDL cholesterol and apoB. In canonical correlation analysis, waist circumference received a greater weight (0.86) than did BMI (0.17) in women. However, the canonical weights were similar for waist (0.46) and BMI (0.56) in men. Only HDL cholesterol (?1.02) carried greater weight in women, whereas in men, triglycerides (0.50), and HDL cholesterol (?0.64) carried a large amount of weight. All the correlation coefficients between BMI, waist circumference, and the first canonical variable of lipids/lipoproteins or between the individual lipid/lipoprotein variables and the first canonical variable of obesity were smaller in women than in men. Triglycerides and HDL cholesterol showed clinically meaningful changes with BMI and waist circumference in men. All lipid/lipoprotein changes in women in relation to BMI and waist circumference were minimal. Discussion: The main lipoprotein abnormality related to obesity in American Indians was decreased HDL cholesterol, especially in men. Central adiposity was more associated with abnormal lipid/lipoprotein profiles than general obesity in women; both were equally important in men.     

Neck Circumference as a Simple Screening Measure for Identifying Overweight and Obese Patients

Objective: There are numerous methods of assessing overweight and obesity. We undertook an observational study to test a method of identifying overweight or obese patients solely by measuring the circumference of the neck. Research Methods and Procedures: A test sample and a second validation sample included 979 subjects (460 men and 519 women), who visited a family medicine clinic in a southern Israeli urban district for any reason between the randomly chosen months of January and September 1998. Main outcome included neck, waist, and hip circumferences; body mass index (BMI); and waist:hip ratio measures. Results: Pearson's correlation coefficients indicated a significant association between neck circumference (NC) and: BMI (men, r = 0.83; women, r = 0.71; each, p < 0.0001), age (men, r = 0.33; women, r = 0.36; each, p < 0.0001), weight (men, r = 0.7; women, r = 0.81; each, p < 0.0001), waist circumference (men, r = 0.86; women, r = 0.85; each, p < 0.0001), hip circumference (men, r = 0.62; women, r = 0.56; each, p < 0.0001), and waist:hip ratio (men, r = 0.66; women, r = 0.87; each, p < 0.0001). NC ≥37 cm for men and ≥34 cm for women were the best cutoff levels for determining the subjects with BMI ≥25.0 kg/m² using the receiver output curve analysis. In the validation unrelated group, the test characteristics were excellent with 98% sensitivity, 89% specificity, and 94% accuracy for men, and 100% sensitivity, 98% specificity, and 99% accuracy for women. NC ≥39.5 cm for men and ≥36.5 cm for women were the best cutoff levels for determining the subjects with BMI ≥30 kg/m² using the receiver output curve analysis. In the validation unrelated group, the test characteristics were excellent with 93% sensitivity, 90% specificity, and 91% accuracy for men, and 93% sensitivity, 98% specificity, and 97% accuracy for women. Discussion: NC measurement is a simple and time‐saving screening measure that can be used to identify overweight and obese patients. Men with NC <37 cm and women with NC <34 cm are not to be considered overweight. Patients with NC ≥37 cm for men and ≥34 cm for women require additional evaluation of overweight or obesity status.     

Socioeconomic status in relation to obesity and abdominal obesity in Korean adults: a focus on sex differences

Objective: We examined the relationship between income and education level with BMI and waist circumference to provide further understanding of the relationship between socioeconomic status and obesity and to identify the presence of sex differences. Research Methods and Procedures: A total of 7962 people ≥20 years of age (3597 men; 4365 women) who participated in the 1998 Korean National Health and Nutrition Examination Survey provided data including height, weight, waist circumference, education, and income level. We examined adjusted BMI and waist circumference according to level of income and education and the association between income and education with obesity and abdominal obesity by multiple logistic regression analysis. Results: In men, significant dose‐response relationships were noted between income and obesity (trend, p < 0.05) and abdominal obesity (trend, p < 0.05). Compared with the lowest income group, the adjusted odds ratios (ORs) (95% confidence interval) of the highest income group for obesity and abdominal obesity were 1.65 (1.18 to 2.32) and 1.37 (0.94 to 1.98), respectively. However, income was not associated with obesity or abdominal obesity in the fully adjusted models in women. With regard to education, women showed significantly decreased ORs, with inverse trends for obesity and abdominal obesity across all education levels. Compared with the lowest education group, the adjusted ORs (95% confidence interval) for obesity and abdominal obesity were 0.66 (0.57 to 0.76) and 0.40 (0.35 to 0.45), respectively, among women with 7 to 12 years of schooling and 0.27 (0.21 to 0.34) and 0.15 (0.12 to 0.18), respectively, among women with 13 or more years of schooling. Discussion: Socioeconomic difference has a considerable impact on the prevalence of obesity among the Korean population, and the patterns differ substantially across sex.