Obesity-related Health Risks Research Articles

Prevalence of obesity, diabetes, and obesity-related health risk factors, 2001.

Obesity and diabetes are increasing in the United States. To estimate the prevalence of obesity and diabetes among US adults in 2001. Random-digit telephone survey of 195 005 adults aged 18 years or older residing in all states participating in the Behavioral Risk Factor Surveillance System in 2001. Body mass index, based on self-reported weight and height and self-reported diabetes. In 2001 the prevalence of obesity (BMI > or =30) was 20.9% vs 19.8% in 2000, an increase of 5.6%. The prevalence of diabetes increased to 7.9% vs 7.3% in 2000, an increase of 8.2%. The prevalence of BMI of 40 or higher in 2001 was 2.3%. Overweight and obesity were significantly associated with diabetes, high blood pressure, high cholesterol, asthma, arthritis, and poor health status. Compared with adults with normal weight, adults with a BMI of 40 or higher had an odds ratio (OR) of 7.37 (95% confidence interval [CI], 6.39-8.50) for diagnosed diabetes, 6.38 (95% CI, 5.67-7.17) for high blood pressure, 1.88 (95% CI,1.67-2.13) for high cholesterol levels, 2.72 (95% CI, 2.38-3.12) for asthma, 4.41 (95% CI, 3.91-4.97) for arthritis, and 4.19 (95% CI, 3.68-4.76) for fair or poor health. Increases in obesity and diabetes among US adults continue in both sexes, all ages, all races, all educational levels, and all smoking levels. Obesity is strongly associated with several major health risk factors.

Abdominal adipose tissue distribution and metabolic risk.

It is now established that waist circumference remains a significant predictor of disease and metabolic risk independent of obesity measured by body mass index. These observations are reinforced by a large body of evidence implicating abdominal obesity measured by imaging modalities in the pathogenesis of numerous metabolic risk factors. However, the extent to which abdominal subcutaneous or visceral adipose tissue (AT) independently contribute to the established association between abdominal obesity and metabolic risk remains a subject of considerable research. Discrepancies in the literature may be partially explained by methodological issues, as currently there is no accepted definition for either visceral or abdominal subcutaneous AT. Accordingly, there is confusion concerning how best to measure these depots in metabolic and descriptive studies. Further, despite numerous studies linking abdominal AT depots with metabolic risk factors, the underlying mechanisms remain unclear. The primary purpose of this review is to examine the independent contribution of visceral and abdominal subcutaneous AT to the aetiology of obesity-related health risk. We begin by considering specific methodological issues with respect to the current classification of abdominal AT as measured by imaging methods. When necessary, we present original data to reinforce important concepts not suitably addressed in the literature. We conclude with a consideration of proposed mechanisms that may link abdominal adiposity and metabolic risk.

Classification of obesity and assessment of obesity-related health risks.

The barriers to the evaluation and treatment of obesity by health-care providers include a lack of awareness of obesity as an independent risk factor for morbidity and mortality and inadequate training in the medical management of obesity. However, the increased risk of medical disorders and emotional consequences associated with obesity make the disorder a priority for physicians to assess and treat. Obesity researchers have published and promoted the use of evidence-based, practical guidelines to educate physicians about how best to approach obesity as a medical disorder. The guidelines support classification and assessment of obesity as an important component of the patient's medical care. Assessment begins with classification by body mass index (BMI), with overweight and obesity defined as a BMI of 25 and 30 kg/m(2), respectively. Patients with high-risk combinations of BMI, waist circumference, and specific cardiovascular risk factors should begin a weight-loss program if no contraindications are present. Proper assessment also includes evaluation of complicating factors for obesity, such as sleep apnea and type 2 diabetes, psychosocial factors, and the use of medications that may contribute to obesity. Special attention should be paid to elements of the physical examination that often are performed incorrectly in obese patients, such as pelvic exams. Gathering this information will allow the clinician to tailor a weight-loss program to each patient individually. Although this represents the most challenging component of obesity care, resources are available to guide the clinician.

The relation of gender, race and socioeconomic status to obesity and obesity comorbidities in a sample of US adults.

To examine the obesity-related chronic diseases in the US adult population according to gender, race and socioeconomic status. Data from the 1994-1996 Continuing Survey of Food Intakes by Individuals (1994-1996 CSFII) conducted by the US Department of Agriculture/Agricultural Research Service (USDA/ARS) were used in the analysis. Relevant data included self-reported weight and height, self-reported physician-diagnosed diabetes mellitus, hypertension, heart disease and high serum cholesterol. Analysis was conducted according to gender, race, income level and education level. There was a graded increase in diabetes, hypertension and high serum cholesterol with increasing body weight in nearly all gender, racial and socioeconomic groups. Among the obese individuals, the prevalence of hypertension was higher in black subjects and the prevalence of diabetes, hypertension and heart disease was higher in individuals with lower education compared to their counterparts. The odds of having diabetes, hypertension, heart disease and high serum cholesterol increased with increasing body weight after adjusting for age, gender, race, income, education and smoking. Although cross-sectional in nature, our results suggest that the disease burden associated with obesity in the population may be substantial. This burden increases with increasing severity of obesity. Our findings support the current opinion that, although the nature of obesity-related health risks is similar in all populations, the specific level of risk associated with a given level of obesity may be different depending on gender, race and socioeconomic condition.

Gastro-oesophageal Reflux in Obese Subjects: Influence of Overweight, Weight Loss and Chronic Gastric Balloon Distension

Background: Gastro-oesophageal reflux is an obesity-related health risk assumed to improve after weight loss. Prolonged intragastric balloon distension might oppose this. The purpose of the study was to investigate the prevalence of gastro-oesophageal reflux in untreated obese subjects and to study the consequences of weight loss with or without intragastric balloon treatment. Methods: Patients participating in a randomized double-blind, sham-controlled trial received balloon or sham treatment for the first 13 weeks. Thereafter, all subjects received a balloon for the remaining year. Twenty-four-hour pH recordings were made at the start, after 13 weeks of balloon or sham treatment, after 26 and 52 weeks of balloon treatment and 13 weeks after balloon removal. Results: Group-wise, pH data of 42 untreated patients (BMI 43.4 kg/m 2 ) were highly abnormal. On an individual level, 22 subjects (52%) had some evidence of reflux, 17 patients (40%) showed pathological total reflux times and 8 (19%) had combined total, upright and supine reflux with grade B reflux oesophagitis in only one patient. Albeit poorly, oesophageal acid exposure was related to body weight and visceral fat distribution. A reduction in acid reflux was observed in sham-treated weight-losing subjects, whereas in balloon-treated subjects supine reflux and duration of the longest reflux increased. In the second 13-week period, the initially improved pH values worsened by balloon placement in sham-treated subjects. Values in balloon-balloon-treated subjects stabilized. After 52 weeks, acid reflux levelled off at pretreatment values and further improved after balloon removal. At these times, decreased visceral fat masses correlated significantly with diminished oesophageal exposure to acid. Conclusions: Obesity predisposed to gastro-oesophageal reflux. Body weight loss and, strikingly, visceral fat loss resulted in improved reflux parameters. Adverse effects on acid reflux by gastric balloon distension wore off over time.

Larger hip circumference independently predicts health and longevity in a Swedish female cohort.

The waist circumference is widely viewed as a simple but effective measure for assessing obesity-related health risks, whereas measurement of the hip circumference is not currently prioritized. This study examines health risks associated specifically with hip circumference in a cohort of Swedish women, to determine whether information may be lost by excluding the hip circumference from health surveys. The subjects described in this report constitute a population-based sample of 38- to 60-year-old women who underwent anthropometric examinations in 1968. The 24-year incidence rates have been ascertained for myocardial infarction, combined cardiovascular diseases, and diabetes. All-cause, cardiovascular, and myocardial infarction mortality also were evaluated. Hip circumference was a significant independent inverse risk estimator for all endpoints studied. Using Cox regression with adjustment for age, smoking, body mass index, and waist circumference, the remaining variability associated with larger hips was associated with significantly fewer adverse health outcomes. The hip circumference became statistically informative after body mass index adjustment. The strongest protective associations were observed for cardiovascular disease and diabetes endpoints, although significant trends were also seen for total mortality. Considering hip and waist simultaneously, the strength of the inverse association for large hips generally exceeded the positive association for waist. Recent interest in the waist circumference as an effective screening tool has taken the focus off of the hip circumference. The present results suggest that collection of hip measurements should not be discontinued in assessment of obesity-related risk status and health promotion.

Care giver perception of children's obesity-related health risk: a study of African American families.

To examine care giver perception of children's weight-related health risk in African American families. One-hundred and eleven families (representing 48 boys and 63 girls) screened for participation in a diabetes prevention study participated. Care givers completed a health awareness questionnaire that assessed their perception of the child's weight, eating habits, appearance, exercise habits, and health risk. The care givers also reported each subject's family history of obesity, diabetes, and other chronic diseases. After a physical examination, height and weight were used to compute an age- and sex-adjusted body mass index for each child. Despite the fact that a substantial number of children were obese (57%) and super-obese (12%), only 44% of the care givers perceived the child's weight to be a potential health problem. Regression analysis showed that 21% of the variance in parental perception of obesity-related health risk could be predicted by child age, body mass index, perception of frame size, and perception of exercise habits. A number of reasons for the apparent minimization of child health risk are discussed, including cultural differences in the acceptance of a large body habitus, lack of knowledge about the connection between childhood obesity and future health risk, and an optimistic bias in the perception of personal health risk.

Weight-related attitudes and behaviors of black women

Weight-related attitudes and practices of women who attended health department clinics or who worked for a health and human services agency were assessed by means of an anonymous, self-administered questionnaire. Black women who were 25 to 64 years old and were not pregnant or had not given birth within the past year were included in this analysis (n = 500). The overweight women perceived themselves as being overweight. They were less likely to be satisfied with their weight and more likely to have dieted and to be currently dieting than nonoverweight women. Awareness of obesity-related health risks was high, but the perceived psychosocial consequences of being overweight were somewhat limited. Approximately 40% of moderately and severely overweight women considered their figures to be attractive or very attractive, which indicates a relatively positive body image. The overweight women were less likely to exercise, less likely to skip meals, and more likely to eat between meals than the nonoverweight women. Among the subset who had ever attempted to lose weight (n = 368), the overweight women were significantly more likely to have regained all or more of the weight lost during their most recent attempt. The findings of this exploratory survey suggest that although overweight black women are weight conscious, the absence of strong negative social pressure combined with a relatively positive body image may limit the extent to which weight loss efforts are sustained. Findings about eating and exercise patterns suggest some specific factors that may interfere with the effectiveness of weight control among black women.

Evaluation of waist size as a health risk indicator for obesity.

The purpose of this study is to evaluate waist size as an indicator of health risk among subjects considered to have normal body construction based on height-weight obesity indices. For estimating standard waist sizes based on height, a regression equation was formulated from 46 male subjects who had no abnormal findings in their health checkups. The regression equation was as follows: Standard waist size (cm) = 0.8 X height (cm)-57.7. The ratio of measured waist size to standard waist size was defined as the "waist ratio". The correlation coefficient between the waist ratio and the modified Broca's obesity index was 0.898 (N = 207, p less than 0.01). To clarify the meaning of the waist ratio, 95 male subjects were divided into three groups on the basis of the difference between their waist ratio and their obesity index. The group whose waist ratios were larger than their obesity indices had significantly worse findings than the group whose waist ratios were not in the following medical categories: systolic blood pressure, glutamic oxaloacetic transaminase levels, gamma glutamyl transpeptidase levels, uric acid levels, total bilirubin, electrocardiogram readings and optic funduscopic observation. Accordingly, the waist ratio derived from waist size might be useful for assessing obesity-related health risks even for subjects judged to be normal from the height-weight obesity index.