Changes in the distribution of body mass index of adults and children in the US population

BACKGROUND: National survey data show increases in mean body mass index (BMI) and in the prevalence of overweight and obesity for adults and children in the United States, indicating a change in the distribution of BMI. OBJECTIVE: To apply graphical methods to describe changes in the distribution of BMI. DESIGN: BMI values from the third National Health and Nutrition Examination Survey (NHANES III: 1988-94) were compared with data from earlier cross-sectional nationally representative surveys for adults 20-74 y of age and for children and adolescents 6-17 y of age. Tukey mean-difference plots were used to investigate the changes in the distributions of BMI within sex-age groups. RESULTS: Mean-difference plots allow qualitative visual comparisons of the distributions of BMI between surveys. For all sex-age groups, there was increasing skewness with a greater shift in the upper part of the distribution so that, within each group, the heaviest subgroup was heavier in NHANES III than in prior surveys. For the youngest children, the lower part of the distribution showed virtually no change. With increasing age the whole distribution tended to shift upward slightly, suggesting an increase in BMI across the entire population. CONCLUSIONS: These changes in the distribution of BMI suggest the combination of both profound environmental determinants and a population with a high degree of susceptibility. The reasons for the increasing prevalence of obesity should be sought in part by seeking to understand the factors causing increases in the population as a whole.     

Trajectories of body mass index and risk of incident hypertension among a normal body mass index population: A prospective cohort study

It is unclear whether there are different body mass index (BMI) trajectories among a population with normal BMI levels, and the association between BMI patterns and incident hypertension is not well characterized. This prospective cohort study includes surveys conducted at baseline and three follow‐ups. 3939 participants who are free of hypertension at baseline or first two follow‐ups were enrolled. At baseline, the age of participants ranged from 35 to 82 years and the mean age was 45.9 years. The BMI trajectories were identified using latent mixture modeling with data from the baseline and first two follow‐ups. The effects of different BMI trajectories on the development of hypertension were analyzed using a Cox proportional hazard model. Four distinct BMI trajectories were identified over the study period (2004‐2010): normal‐stable (n = 1456), normal‐increasing (n = 2159), normal‐fluctuated (n = 166), and normal‐sharp‐increasing (n = 158). Relative to the normal‐stable BMI group, the hazard ratios (HRs) and 95% confidence intervals (CIs) after adjustment for confounding factors of the normal‐increasing, normal‐fluctuated, and normal‐sharp‐increasing groups were 1.244 (1.103‐1.402), 1.331 (1.008‐1.756), and 1.641 (1.257‐2.142), respectively. Additionally, subgroup analysis showed that the normal‐fluctuated BMI trajectory was associated with a significantly higher risk of hypertension only in women (HR = 1.362; 95% CI = 1.151‐1.611). The BMI trajectories were significant predictors of hypertension incidence, and increasing BMI trajectories within the currently designated normal range were associated with an increased hypertension risk, especially in women.     

Longitudinal changes of body mass index, spirometry and diffusion in a general population.

The aim of this study was to evaluate the effects of body mass index (BMI) changes over an 8-yr follow-up, on longitudinal changes of vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and carbon monoxide diffusing capacity of the lung (DL,CO) indices in a general population sample of North Italy. To avoid including weight changes possibly related to physical growth, only the 1,426 adults (>24 yrs, 46% males) with complete follow-up were selected. Median linear regression models were applied to estimate the medians of change (computed as follow-up minus baseline values) of VC, FVC, FEV1 and DL,CO indices, as functions of changes of BMI over the follow-up period, separately by sex, after considering several potential confounders and effect modifiers. The extent of lung function loss tended to be higher among those who, at baseline, reported greater BMI values. Males experienced larger losses than females (20 and 16 mL FEV1 median reduction for a BMI unit increase in males and females, respectively). Conversely, longitudinal changes of BMI caused a slight and nonsignificant increase in DL,CO values in both sexes. Over an 8-yr follow-up, the detrimental effect of gaining weight might be reversible for many adults as most of those who reduced their body mass index values also increased their lung function. Overweight patients with ventilatory impairment should be routinely encouraged to lose weight for improving their lung function.     

Relationship between body mass index and high cystatin levels among US adults

High cystatin C levels among patients without clinically recognized chronic kidney disease (CKD) may identify patients who are at preclinical stages of CKD. Higher body mass index (BMI) has been found to be associated with increased risk of CKD. However, the association between BMI and high cystatin C levels is not clear. The authors examined participants older than 20 years from the National Health and Nutrition Examination Survey 1999 to 2002 (N=2583, 50.2% women). BMI was categorized as <25 kg/m(2), 25-29.9 kg/m(2), and ≥30 kg/m(2) . Main outcome was high cystatin C (>1 mg/dL) among patients without clinically recognized CKD (estimated glomerular filtration rate <60 mL/min/1.73 m(2) or microalbuminuria). Higher BMI was positively associated with high cystatin C, independent of age, sex, race-ethnicity, education, smoking, alcohol intake, cholesterol, and C-reactive protein levels. Compared with patients with BMI <25 kg/m(2) (referent), the multivariable odds ratio (95% confidence interval) of high cystatin C was 2.53 (1.79-3.58) (P trend <.0001 among patients with BMI ≥30 kg/m(2)). The association between BMI and high cystatin C persisted in subgroup analyses by sex, race-ethnicity, and among those without diabetes or hypertension. Among US adults without clinically recognized CKD, higher BMI levels were independently associated with high cystatin C levels.     

Sleep duration and body mass index in a rural population

BACKGROUND: A growing body of epidemiological evidence suggests an association between short sleep duration and obesity. Recently, potential hormonal links have been observed that may account for the relationship. The possible connection between sleep duration and body mass index (BMI) has not been explored in rural populations. Rural populations are of interest because obesity rates are high and lifestyle patterns of nutrition, physical activity, work hours, and sleep may differ from those in urban and suburban populations. We conducted this study to determine whether short sleep duration is related to BMI and obesity in a rural population in southeast Iowa. METHODS: We conducted a cross-sectional analysis of data collected in the Keokuk County Rural Health Cohort Study, 1999-2004. Study participants were from a population-based sample consisting of 990 employed adults in a rural community in southeastern Iowa. The main outcome measure was BMI. Multiple linear regression modeling was used to adjust for potential confounding variables. RESULTS: Self-reported sleep duration on weeknights was negatively correlated (beta = -0.42; 95% confidence interval, -0.77 to -0.07) with higher BMI after adjusting for sex, age, educational achievement, physical job demand, household income, depressive symptoms, marital status, alcohol consumption, and snoring. CONCLUSION: These data support an association between short sleep duration and higher BMI in this rural population, which is consistent with the relationship found in other settings.     

Asthma, body mass index, and C-reactive protein among US adults.

Obesity, a state that may be characterized by a low-grade inflammation, has been associated with asthma. C-reactive protein, an acute phase reactant, is elevated in obese people. However, little is known about how asthma affects C-reactive protein concentrations. Using data from 14,224 participants of the Third National Health and Nutrition Examination Survey (1988-1994), the author examined C-reactive protein concentrations among participants with current asthma (n = 651), who formerly had asthma (n = 303), and who never had asthma (n = 13,270). Compared with 21% of participants with current asthma, 11% with former asthma (P < .001) and 15% without asthma (P = .018) had C-reactive protein concentrations > or = 85th percentile of the sex-specific distribution. Compared with participants without asthma, the age-adjusted odds ratios for having an elevated C-reactive protein concentration was 1.49 (95% confidence interval [CI]: 1.11, 2.00) for persons with current asthma. After adjusting for age, sex, race or ethnicity, years of education, cotinine concentration, body mass index, waist-hip ratio, physical activity level, aspirin use, oral corticosteroid use, and inhaled corticosteroid use, the odds ratio decreased to 1.15 (95% CI: 0.83, 1.59). Body mass index was the main reason for the attenuation of the odds ratio. Whether the inflammatory activity associated with body mass index contributes to the pathophysiology of asthma is unknown.     

Obesity in Auckland school children: a comparison of the body mass index and percentage body fat as the diagnostic criterion.

OBJECTIVES: First, to determine obesity rates in Auckland school children according to their ethnic group using two different criteria: the body mass index (BMI) and percentage body fat (PBF) derived from bioelectrical impedance analysis (BIA). Second to examine the relationship between BMI and body composition across ethnic groups to determine if BMI references from European children accurately reflect obesity in other ethnic groups. DESIGN: A total of 2273 Auckland school children, aged 5-10.9 y had their height, weight and bioelectrical impedance measured. Using these measurements, each child's BMI, fat free mass, fat mass and PBF were derived. RESULTS: In all 14.3% of children were obese using the recommended definition of obesity (BMI) greater than the 95th percentile). There was no clinically significant difference in the relationship between BMI and body composition in different ethnic groups. Obesity rates varied with ethnicity (P<0.0001) and were higher in Pacific Island (24.1%) and Maori (15.8%) than in European children (8.6%). Obesity rates also varied with age (P<0.03), with the highest rates in older children. PBF levels were higher in females than males (P<0.0001). Using a definition of obesity based on percentage body fat (PBF>30%), obesity rates were higher in all ethnic groups. CONCLUSIONS: Obesity rates are high in Auckland school children and there are clear differences in obesity rates in different ethnic groups. If BMI criteria are used to define obesity in our population, we recommend the same standards be used for children of all ethnicities.     

The relationship between body mass index and self-reported functional limitation among older adults: a gender difference

OBJECTIVES: To determine whether there is a gender difference in how body mass index (BMI) relates to self-reported functional limitation. Also, to evaluate whether the method of categorizing BMI changes the observed results. DESIGN: Cross-sectional cohort study. SETTING: Rural Pennsylvania. PARTICIPANTS: A total of 7,120 male (n = 3,312) and female (n = 3,808) community-dwelling older adults enrolled in a Medicare managed-risk contract. MEASUREMENTS: All subjects completed a modified Level II Nutrition Risk Screen upon enrollment in the health plan. Height and weight were obtained by nursing personnel during an enrollment clinic visit. Subjects who reported 10 or more pounds weight loss in the previous 6 months were excluded. Logistic regression was used to evaluate the relationship between BMI and self-reported functional limitation separately for each sex, adjusting for age, depression, and polypharmacy. Two schemes were used to categorize BMI: equally distributed sex-specific quintiles and arbitrary division based on National Institutes of Health (NIH) Obesity Guidelines. RESULTS: How BMI relates to functional limitation depends upon both sex and method of categorizing BMI. When BMI was considered in gender-specific quintiles, women in the highest quintile of BMI had increased risk of functional impairment; there was no relationship between BMI and functional limitation for men. When BMI was categorized by the NIH obesity guidelines, both men and women with BMI >40 had significantly increased risk of functional limitation. CONCLUSIONS: The mechanisms behind gender discrepancy in self-reported functional limitation remain unclear. Studies may need to consider men and women separately, because how BMI relates to function depends on gender. Further research is needed to evaluate how changes in weight and body composition during middle and old age affect functional status.     

A Hattori chart analysis of body mass index in infants and children

BACKGROUND: Body mass index (BMI) is widely used as an index of fatness in paediatrics, but previous analysis of the BMI-fatness relationship has been insufficient. OBJECTIVE: To consider the effects of variation in fat-free mass (FFM) and fat mass (FM) on BMI in infants, children and Fomon's reference child (Am J Clin Nutr 1982; 35: 1169-1175). SUBJECTS: 42 infants aged 12 weeks; 64 children aged 8-12 y; Fomon's reference child. METHODS: FFM was measured by deuterium dilution. FFM index (FFMI) and FM index (FMI) were calculated. The effects of variation in FFM and FM on BMI were explored using Hattori's body composition chart (Am J Hum Biol 1997; 9: 573-578). RESULTS: In both infancy and childhood, a given BMI can embrace a wide range of percentage body fat. At both time points, the s.d. of FFMI was > 60% of the s.d. of FMI. Graphic analysis differentiated the effects of lean tissue and fat deposition on BMI with age in the reference child. CONCLUSION: Although valuable for assessing short-term changes in nutritional status in individuals, and for comparing mean relative weight between populations, BMI is of limited use as a measure of body fatness in individuals in both infancy and childhood. The development of BMI with age may be disproportionately due to either FFM and FM at different time points.     

Family lifestyle and parental body mass index as predictors of body mass index in Australian children: a longitudinal study.

OBJECTIVE: To investigate associations between body mass index (BMI) and family characteristics, including lifestyle, in parents and offspring from Australian families. DESIGN AND SUBJECTS: Longitudinal survey of 219 families of Australian children who had been surveyed 3-yearly between the ages of 9 and 18 y. MEASUREMENTS: Socio-economic status, weight and height, diet from 3 day records or food frequency questionnaires, alcohol consumption, smoking habits and physical fitness in offspring (bicycle ergometry in 18-y-olds). RESULTS: In 18-y-olds, in models examining offspring's lifestyle variables, BMI was predicted negatively by physical fitness (P=0.012), and positively by alcohol intake (P=0.046) in sons while, in daughters, only a negative association with physical fitness was significant. In models including parental characteristics, BMI in 18-y-old sons and daughters was significantly predicted by mothers' and fathers' BMI, independently of offsprings' alcohol intake, smoking, physical fitness and parents' education, and, in daughters, by fathers' alcohol intake. These models explained 48% of variance in daughters and 33% in sons. In both sons and daughters, BMI over the 9 y of the survey was consistently higher in offspring with overweight or obese fathers (P=0.033 for sons, P=0.024 for daughters) or mothers (P=0.031 for sons, P=0.037 for daughters). Physical fitness at the ages of 12, 15 and 18 y was negatively related to fathers' obesity in daughters and mothers' obesity in sons. Obesity in fathers was associated with a four-fold increase in risk of obesity at the age of 18 y in both sons and daughters with an independent eight-fold increase in risk for daughters if mothers were obese. Birthweight was unrelated to overweight or obesity in the 18-y-olds. Alcohol intake in sons related significantly to alcohol intake in either parent while, for daughters, there was a significant association only with fathers' alcohol consumption. In daughters, fat intake was positively associated with fat intake score in both fathers and mothers. CONCLUSION: Parental overweight or obesity may identify children at risk for a range of unhealthy behaviours. Promotion of a healthy lifestyle targeting overweight families, particularly in lower socio-economic groups, should be a priority.     

Characteristics of asthma among elderly adults in a sample of the general population

This article describes the characteristics and course of asthma among subjects who were older than 65 years at the time of enrollment in a longitudinal study of a general population sample. It was present in 3.8 percent of men and 7.1 percent of women. An additional 4.1 percent of men reported having "asthma," but they also had seen a physician for "emphysema" and had smoked significantly; their "asthma" diagnosis is regarded as highly questionable. They did not show the elevated rate of allergy skin test reactivity of high serum IgE levels that were characteristic of other asthmatics. Many of the elderly asthmatics (mean age, 72 years) had severe disease with marked ventilatory impairment. There was a close relationship between the severity of wheezing complaints and impairment of the FEV1. Of the 46 patients, 48 percent reported an onset before age 40 years. There was no relationship between severity and age of onset or duration of disease. A second diagnosis of "chronic bronchitis" was reported by 46 percent of the asthmatics, but this did not delineate a distinctive group with late-onset, smoking-related disease. Death rates in the asthmatics tended to be higher than in nonasthmatics (odds ratio, 1.9; CI, 0.998 to 3.70, after stratifying by sex). Over a mean follow-up of 7.44 years, most symptoms as well as the FEV1 remained relatively stable. Chronic productive cough did tend to remit (p less than 0.01), but this was noted in the nonasthmatics as well. We estimate that no more than 19 percent of the asthmatics went into complete remission during follow-up. Most of these had mild initial symptoms; there were no remissions in subjects with severe disease at the time of entry. We concluded that asthma in the elderly is not a rare disease and may be associated with severe symptoms and chronic airways obstruction. If severe, it rarely goes into complete remission but tends to remain a severe, disabling disorder.     

Changes in body mass index in a Finnish population between 1972 and 1982

Population-based data on changes in body mass index are scarce. We have examined about 9700 people aged 30-59 years in two provinces of East Finland in 1972, 1977 and 1982. The age adjusted mean value of body mass index (kg m-2) in 1972 was 26.0 +/- 3.4 in men and 26.9 +/- 4.7 in women, increasing with age. During the 10-year follow-up the mean body mass index increased in men to 26.5 +/- 3.6 (P less than 0.001). In women we found a decrease in mean body mass index to 26.4 +/- 4.9 (P less than 0.001). The increase trend in body mass with age remained in women, while in men the age trend increased from survey to survey. The proportion of obese men also increased while in younger women a decrease was observed. The results of this study show the association between changes in physical activity, education etc. and the observed changes in the body mass index.     

A common polymorphism is associated with body mass index in Uyghur population

We aimed at observing the association of a common genetic variant near the INSIG2 gene (rs7655505) with body mass index (BMI) related obesity in a population-based association study in Uyghur population. We observed a significant association of rs7566605 polymorphism with BMI related obesity in Uyghurs with an odds ratio of 1.47 (95% CI 1.11–1.95, P = 0.006) under a dominant model (CC + GC versus GG). The mean BMI of rs7566605 CC + GC was 0.59 kg/m² higher than for GG genotype (P = 0.024), regardless of sex and age.     

Prevalence of dysglycemia and its associations with age and body mass index among community dwelling adults in a developing country

International Journal of Diabetes in Developing Countries - Dysglycemia includes prediabetes and diabetes. We aimed to study the prevalence of dysglycemia, and its associations with age and body...     

Prognostic value of body mass index in the development of cardiovascular diseases among Kaunas male population.

The paper presents the results of a primary medical examination and of a prospective, on the average 14-year follow-up study of the male population of Kaunas aged 45-59 years (n = 2452). The prevalence of overweight, according to the WHO criteria, was 48.7%, that of obesity 20.5%. With increasing body mass index (BMI) there occurred a statistically significant increase of main risk factors of ischaemic heart disease (IHD) and of IHD itself. The results of the prospective study showed a U-shaped relationship between BMI and mortality from all cardiovascular diseases, and a J-shaped relationship between BMI and mortality from IHD and morbidity of acute myocardial infarction, respectively. The same relationship held true even after standardization of the level of all other risk factors using the multiple logistic function. Thus, the overweight was confirmed as an independent IHD risk factor in the given population.     

成年人群功能性肠病与体质量指数的相关性研究

目的探讨成年人群功能性肠病与体质量指数的相关性。 方法回顾性分析2016年1月至2019年2月在宁夏回族自治区人民医院消化内科确诊的50例功能性肠病患者为病例组,同期行健康体检者50例为对照组。根据《中国成人超重和肥胖症预防控制指南》推荐的标准,以体质量指数作为不同体重分类依据,采用两独立样本t检验方法比较两者相关性。 结果病例组与对照组比较中,年龄、性别、民族、身高、体重比较差异无统计学意义(P>0.05),而吸烟、饮酒、睡眠情况及进食辛辣食物比较差异有统计学意义(P>0.05);体质量指数与功能性肠病无关(P>0.05),但女性患者功能性肠病的占比较男性多;功能性肠病患者体重过低组占比达20.0%,而健康体检人群超重/肥胖所占比例达44.0%。 结论成年人群功能性肠病与吸烟、饮酒、睡眠情况及进食辛辣食物有关,而与年龄、性别、民族、体质量指数不存在相关性。