Using concentration index to study changes in socio-economic inequality of overweight among US adolescents between 1971 and 2002

BACKGROUND: The prevalence of overweight among adolescents continues to increase in the United States. This study examines the changes in socio-economic status (SES) inequality of overweight among US adolescents in the past three decades. METHODS: Concentration Index (CI) was utilized to measure changes in the SES inequality in prevalence of overweight among US adolescents. Data collected from 15,286 adolescents in four waves of the National Health and Nutrition Examination Surveys (NHANES) between 1971 and 2002 and Hispanic Health and Nutrition Examination Survey (HHANES) (1982-84) were used. RESULTS: Changes in the SES inequality of overweight among US adolescents and considerable gender and ethnic differences were detected. For boys, CI varied from 0.04 in NHANES I to -0.04 in NHANES 1999-2002; for girls, CI varied from -0.12 in NHANES I to -0.18 in NHANES III. Among whites, SES disparity peaked in NHANES III and declined thereafter. Patterns in black and Mexican-American adolescents were mixed. CONCLUSIONS: Patterns of SES disparity of overweight among US adolescents varied across ethnic and gender groups, and have changed over time. Disparities have decreased since the early 1990s with the rise of the obesity epidemic. Obesity prevention and management efforts should target all SES groups in the United States.     

Prevalence of overweight and obesity among adults with diagnosed diabetes--United States, 1988-1994 and 1999-2002

Obesity in persons with diabetes is associated with poorer control of blood glucose levels, blood pressure, and cholesterol, placing persons with diabetes at higher risk for both cardiovascular and microvascular disease. Conversely, intentional weight loss is associated with reduced mortality among overweight persons with diabetes. CDC analyzed the prevalence of overweight and obesity among U.S. adults aged >/=20 years with previously diagnosed diabetes by using data from two surveys: the Third National Health and Nutrition Examination Survey (NHANES III), 1988-1994, and NHANES 1999-2002. This report summarizes the results of that analysis, which indicated that most adults with diagnosed diabetes were overweight or obese. During 1999-2002, the prevalence of overweight or obesity was 85.2%, and the prevalence of obesity was 54.8%. Encouraging patients to achieve and maintain a healthy weight should be a priority for all diabetes-care programs.     

Drug use and sexual behaviors reported by adults: United States, 1999-2002

This report presents prevalence estimates for self-reported adult drug use and sexual behaviors in the United States. Data are from the National Health and Nutrition Examination Survey (NHANES) collected from 1999 to 2002. NHANES surveys a stratified multistage probability sample of the civilian noninstitutionalized population of the United States. Tables included in this report present estimates for use of cocaine, including crack or freebase, or other street drugs, and sexual behavior by selected sociodemographic characteristics among adults 20-59 years of age.     

Overweight among students in grades K-12--Arkansas, 2003-04 and 2004-05 school years

Prevalence of overweight among children nearly doubled from 1976-1980 to 1999-2002 in the United States. During 1999-2002, approximately 65% of adults aged > or =20 years were overweight or obese, according to the National Health and Nutrition Examination Survey (NHANES). Among persons aged 6-19 years during the same period, 31% were overweight or at risk for overweight. In 2003, the Youth Risk Behavior Surveillance (YRBS) survey indicated that 27% of high school students were overweight or at risk for overweight. Among adolescents with a body mass index (BMI) at or above the 95th percentile, approximately 50% will become obese adults, and 70% will become obese or overweight adults. Although NHANES and YRBS provide population-based, cross-sectional state and national samples, no studies reflect a national or statewide longitudinal cohort assessment of childhood and adolescent obesity. The American Academy of Pediatrics (AAP) and the Institute of Medicine recommend annual assessments of BMI as a strategy for preventing and combating childhood obesity. In 2003, Arkansas implemented a multifaceted statewide initiative to reduce and prevent overweight among children. A key aspect of this initiative (Act 1220) is the mandated annual statewide BMI assessments of all Arkansas public school students with confidential reporting of results to parents. This report describes the results of this large-scale population screening, which indicated that, during the 2003--04 and 2004--05 school years, 38% of Arkansas students were overweight or at risk for overweight. This finding suggests a more severe problem than that reported for other states. Because rates of childhood and adolescent obesity in certain areas might be higher than anticipated, health policy decisions that address health outcomes and cost of care should be based on state-specific, population-based data.     

Anthropometric reference data for children and adults: U.S. population, 1999-2002

This report presents national anthropometric reference data based on health examination survey results from the National Health and Nutrition Examination Survey (NHANES), 1999-2002, for all ages of the U.S. population. Weighted population means, standard errors of the means, and selected percentiles are presented for the total U.S. population by sex, race or ethnic group, and age in years or age group. Findings for some population groups are reported in a way that is comparable with results reported from National Health Examination Surveys (NHES) and NHANES conducted between 1960 and 1994. These data add to the knowledge about trends in child growth and development and are used to monitor prevalent conditions in the U.S. population such as overweight and obesity.     

Height, weight, and body mass index of American Indian schoolchildren, 1990–1991

Objective To describe the current height and weight status of American Indian children who live on or near Indian reservations nationwide.Subjects 9,464 American Indian schoolchildren aged 5 through 18 years.Statistical analyses performed Data for height, weight, and body mass index of the schoolchildren were compared with two national reference data sets, the second National Health and Nutrition Examination Survey (NHANES II) and the Mexican-American population of the Hispanic Health and Nutrition Examination Survey (HHANES-MA).Results The three populations were similar in height, but the American Indian children weighed more, although not at a statistically significant level, and had a statistically significant higher body mass index than the NHANES II reference population for nearly every age and sex group. The overall prevalence of overweight in the American Indian children (exceeding the 85th percentile of the reference population) was 39.3% compared with the NHANES II population and 28.6% compared with the HHANES-MA population. The overall prevalence of underweight in the American Indian sample was substantially less than the expected 15% compared with either the NHANES II or HHANES-MA population.Applications/conclusions Overweight is much more prevalent in American Indian children than among other children in the United States at all ages and in both sexes. This may have important implications for chronic disease risk and emphasizes the need for targeting obesity prevention efforts to American Indian children.     

Prevalence of chronic kidney disease and associated risk factors--United States, 1999-2004

Chronic kidney disease (CKD) is a serious condition associated with premature mortality, decreased quality of life, and increased health-care expenditures. Untreated CKD can result in end-stage renal disease and necessitate dialysis or kidney transplantation. Risk factors for CKD include cardiovascular disease, diabetes, hypertension, and obesity. To estimate the prevalence of CKD in the United States (overall and by health risk factors and other characteristics), CDC analyzed the most recent data from the National Health and Nutrition Examination Survey (NHANES). This report summarizes the results of that analysis, which determined that 16.8% of the U.S. population aged >/=20 years had CKD, according to 1999-2004 NHANES data, compared with 14.5% from the 1988-1994 NHANES (i.e., NHANES III), an increase of 15.9% based on crude estimates of prevalence. Persons with diabetes or cardiovascular disease had a greater prevalence of CKD than persons without those conditions. The results underscore the need to continue surveillance for CKD and its risk factors in the United States and to implement new strategies to reduce the number of persons with this condition.     

The Hunger–Obesity Paradox: Obesity in the Homeless

Despite stereotypes of the homeless population as underweight, the literature lacks a rigorous analysis of weight status in homeless adults. The purpose of this study is to present the body mass index (BMI) distribution in a large adult homeless population and to compare this distribution to the non-homeless population in the United States. Demographic, BMI, and socioeconomic variables from patients seen in 2007–2008 were collected from the Boston Health Care for the Homeless Program (BHCHP). This population was compared to non-homeless adults from the National Health and Nutrition Examination Survey (NHANES). Among 5,632 homeless adults, the mean BMI was 28.4 kg/m² and the prevalence of obesity was 32.3 %. Only 1.6 % of homeless adults were underweight. Compared to mean BMI in NHANES (28.6 kg/m²), the difference was not significant in unadjusted analysis (p = 0.14). Adjusted analyses predicting BMI or likelihood of obesity also showed that the homeless had a weight distribution not statistically different from the general population. Although underweight has been traditionally associated with homelessness, this study suggests that obesity may be the new malnutrition of the homeless in the United States.     

A study of dietary patterns in the Mexican-American population and their association with obesity

OBJECTIVE: Data from the National Health and Nutrition Examination Survey 2001-2002 indicate that prevalence of overweight and obesity continues to rise among Mexican Americans. Little is know about the dietary factors associated with this trend. Ethnic groups have different dietary patterns based on their geographical locations and cultural influences. We examined the dietary patterns of Mexican Americans and their association with total and central obesity. We hypothesized that Mexican-American adults following a traditional diet would have a lower prevalence of obesity than those following a more typical American diet. SUBJECTS: Data from the National Health and Nutrition Examination Survey 2001-2002 included 659 Mexican-American adults, ages 18 years and older. EXPERIMENTAL DESIGN: Dietary patterns were defined by cluster analysis of food group variables, expressed as percentage contribution to total energy intake. Obesity was assessed by body mass index (calculated as kg/m2) and central obesity by waist circumference. RESULTS: We defined four dietary patterns, each named for the food groups that were most predominant relative to the other clusters: poultry and alcohol, milk and baked products, traditional Mexican, and meat. Surprisingly, we did not identify a clear "healthy pattern" group in this population, as has been generally observed in other ethnic groups. Although the traditional Mexican diet contains relatively high intakes of legumes and dietary fiber, it also was high in cholesterol. Contrary to our hypothesis, those consuming the traditional Mexican diet pattern had high BMI and waist circumference values, which did not differ significantly from other groups. CONCLUSION: In this representative population of Mexican-American adults, we identified distinct dietary patterns, but these were not significantly associated with obesity. Rather, obesity was prevalent in all diet groups. More details on possible changes within the traditional pattern, including use of fast food vs home-prepared Mexican foods, are needed to better understand how diet can be associated with obesity in this population.     

Trends in intake of energy and macronutrients--United States, 1971-2000

During 1971-2000, the prevalence of obesity in the United States increased from 14.5% to 30.9%. Unhealthy diets and sedentary behaviors have been identified as the primary causes of deaths attributable to obesity. Evaluating trends in dietary intake is an important step in understanding the factors that contribute to the increase in obesity. To assess trends in intake of energy (i.e., kilocalories [kcals]), protein, carbohydrate, total fat, and saturated fat during 1971-2000, CDC analyzed data from four National Health and Nutrition Examination Surveys (NHANES): NHANES I (conducted during 1971-1974), NHANES II (1976-1980), NHANES III (1988-1994), and NHANES 1999-2000. This report summarizes the results of that analysis, which indicate that, during 1971--2000, mean energy intake in kcals increased, mean percentage of kcals from carbohydrate increased, and mean percentage of kcals from total fat and saturated fat decreased. An expert advisory committee appointed by the U.S. Department of Health and Human Services and the U.S. Department of Agriculture (USDA) is conducting a review of the Dietary Guidelines for Americans. Revised guidelines will be published in 2005.