Highest Body Mass Index Quintile Research Articles

Body mass index and body fat distribution and new-onset atrial fibrillation: Substudy of the European Prospective Investigation into Cancer and Nutrition in Norfolk (EPIC-Norfolk) study

Background and aimObesity is a recognized risk factor for new-onset atrial fibrillation (AF). The association between body fat distribution, which is measured by body mass index (BMI) and waist–hip ratio (WHR), its changes, and new-onset AF is conflicting. Methods and resultsParticipants of the European Prospective Investigation into Cancer and Nutrition in Norfolk cohort study were included, with exclusion criteria of prevalent AF, rheumatic heart disease, and cancer. AF was confirmed by the International Classification of Diseases-10 hospital discharge code I48. Adjusted sex-specific Cox proportional hazards models were used to quantify the AF risk per 1 standard deviation increase and for quintiles of adiposity indices. A total of 10,885 men and 12,857 women were followed up for a median of 19 years, yielding 451,098 person-years. New-onset AF was diagnosed in 1408 (12.9%) men and 1102 (8.6%) women. Multivariable analyses showed that BMI predicted new-onset AF in all, while WHR predicted only in men. New-onset AF risk gradually increased across the range of adiposity indices: for men in the highest BMI quintile, HR: 1.59 (CI 1.32–1.91, p for trend<0.001), whereas for women in the highest BMI quintile, HR: 1.52 (CI 1.23–1.88, p for trend<0.001). Further, for men in the highest WHR quintile, HR: 1.31 (CI 1.09–1.57, p for trend: 0.01), whereas for women in the highest WHR quintile, HR: 1.12 (CI 0.90–1.41, p for trend: 0.17). The change in BMI and WHR was similar in participants with or without new-onset AF. ConclusionsAn increased body mass, as measured by BMI, is associated with an increased risk of developing new-onset AF. More abdominal fat distribution, as measured by WHR, is associated with an increased risk of developing new-onset AF in men but not in women.

Survival in patients on hemodialysis: Effect of gender according to body mass index and creatinine.

BackgroundThe association of a higher body mass index (BMI) with better survival is a well-known “obesity paradox” in patients on hemodialysis (HD). However, men and women have different body compositions, which could impact the effect of BMI on mortality. We investigated the effect of gender on the obesity-mortality relationship in Korean patients on HD.MethodsThis study included 2,833 maintenance patients on HD from a multicenter prospective cohort study in Korea (NCT00931970). The relationship between categorized BMI and gender-specific mortality was evaluated by an adjusted Cox proportional hazard model with restricted cubic spline analyses and the Competing risk analysis. We also investigated the effect of changes in BMI over 12 months and serum creatinine level on survival in male and female patients on HD.ResultsThe mean BMI was 22.6 ± 3.3 kg/m2 and the mean follow up duration was 24.2 ± 3.4 months. The patients with the highest quintile of BMI (≥25.1 kg/m2) showed lower mortality (subdistributional hazard ratio [SHR] = 0.63, 95% confidence interval [CI] = 0.43–0.93, P = 0.019) compared with those with the reference BMI quintile. When analyzed by gender, male patients with a BMI over 25.1 kg/m2 had lower mortality risk (HR = 0.43, 95% CI = 0.25–0.75, P = 0.003); however, no significant difference was found in female patients. Increased BMI after 12 months and high serum creatinine were associated with better survival only in male patients on HD.ConclusionsBMI could be used as a risk factor for mortality in male patients on HD. However, the mortality of female patients on HD was not related with baseline and follow-up BMI. This suggests that BMI is a good surrogate marker of lean body composition, especially in male patients on HD.

Abstract P105: Early Adolescent Waist Size and Body Mass Index are Stronger Predictors of Lipid Levels After Ten Years Than Percent Body Fat in Black and White Girls

Cardiometabolic risk begins in childhood and poses additional hazards for later chronic disease. In this study, we assessed the hypothesis that pre-adolescent measures of body fat (ages 9-10 years) would predict later adolescent lipid levels (ages 17-20 years) and that racial differences may exist in the efficacy of particular measures of body fat for predicting future lipid levels. Data from the NHLBI’s Growth and Health Study were used to evaluate the independent effects of early adolescent body mass index (BMI), waist circumference (WC), and percent body fat (%BF) - all distinct measures of body composition - in this cohort of Caucasian (white) and African-American (black) girls, initially 9-10 years of age. Girls with complete data (n=634, white; n=738, black) for body fat, relevant confounders, and follow-up lipid levels (i.e., HDL, LDL, and triglycerides) at 17-20 years of age were included. In late adolescence, there were statistically significant trends of increasing LDL and triglycerides and decreasing HDL levels (p&lt;0.05 for all) across quintiles of all body fat measures at 9-10 years of age. By 17-20 years, white girls (vs. black girls) in the highest BMI quintile had slightly higher mean LDL levels (112.7 vs. 105.1), lower HDL levels (48.0 vs. 51.4), and much higher triglyceride levels (109.8 vs. 76.8 mg/dL). After adjusting for age, SES, height, age at menarche, physical activity, television viewing, fruit and vegetable consumption, and dietary fiber, WC was the strongest predictor of late-adolescent triglycerides and HDL levels in both whites and blacks while BMI was an equally-good predictor of LDL. Percent body fat using bioelectrical impedance analysis was generally a weaker predictor of lipid outcomes. Girls in the highest quintile (Q5) of WC had mean triglyceride levels that were 31.1 and 14.9 mg/dL higher than those in the lowest quintile (Q1), for whites and blacks, respectively; mean differences (Q5-Q1) in TG associated with BMI were 27.7 and 12.0 mg/dL, and for %BF were 13.6 and 7.2 mg/dl, respectively. White and black girls, respectively, in Q5 of WC at 9-10 years of age had HDL levels that were 7.8 mg/dL lower in late adolescence than those of girls in Q1. These results suggest that WC and BMI as simple anthropometric measures of body fat in pre-adolescent girls may be useful in identifying girls who are at risk for dyslipidemia by the time of later adolescence.

Obesity and Life Expectancy Among Long-Lived Black Adults

In samples of African Americans and the elderly adults, obesity is often not found to be a risk factor for mortality. These data contradict the evidence linking obesity to chronic disease in these groups. Our objective was to determine whether obesity remains a risk factor for mortality among long-lived black adults. The Adventist Health Study 2 is a large prospective cohort study of Seventh-day Adventist church members who are encouraged by faith-based principles to avoid tobacco, alcohol, and meat consumption. We conducted an attained age survival analysis of 22,884 U.S. blacks of the cohort-half of whom attained an age of 58-108 years during the follow-up (adult life expectancy of 84 years in men, 89 years in women). Women in the highest body mass index quintile (>33.8) experienced a significant 61% increase (hazard ratio [95% CI] = 1.62 [1.23, 2.11] relative to the middle quintile) in mortality risk and a 6.2-year (95% CI = 2.8-10.2 years) decrease in life expectancy. Men in the highest body mass index quintile (>30.8) experienced a significant 87% increase (hazard ratio [95% CI] = 1.87 [1.28, 2.73] relative to the middle quintile) in mortality risk and 5.9-year (95% CI = 2.1- 9.5 years) decrease in life expectancy. Obesity (>30) was a significant risk factor relative to normal weight (18.5-24.9) in never-smokers. Instantaneous hazards indicated excess risk from obesity was evident through at least age 85 years. The nonobese tended to follow plant-based diets and exercise vigorously. Avoiding obesity promotes gains in life expectancy through at least the eighth decade of life in black adults. Evidence for weight control through plant-based diets and active living was found in long-lived nonobese blacks.

Body Size, Mammographic Density, and Breast Cancer Risk

Greater weight and body mass index (BMI) are negatively correlated with mammographic density, a strong risk factor for breast cancer, and are associated with an increased risk of breast cancer in postmenopausal women, but with a reduced risk in premenopausal women. We have examined the associations of body size and mammographic density on breast cancer risk. We examined the associations of body size and the percentage of mammographic density at baseline with subsequent risk of breast cancer among 1,114 matched case-control pairs identified from three screening programs. The effect of each factor on risk of breast cancer was examined before and after adjustment for the other, using logistic regression. In all subjects, before adjustment for mammographic density, breast cancer risk in the highest quintile of BMI, compared with the lowest, was 1.04 [95% confidence interval (CI), 0.8-1.4]. BMI was associated positively with breast cancer risk in postmenopausal women, and negatively in premenopausal women. After adjustment for density, the risk associated with BMI in all subjects increased to 1.60 (95% CI, 1.2-2.2), and was positive in both menopausal groups. Adjustment for BMI increased breast cancer risk in women with 75% or greater density, compared with 0%, increased from 4.25 (95% CI, 1.6-11.1) to 5.86 (95% CI, 2.2-15.6). BMI and mammographic density are independent risk factors for breast cancer, and likely to operate through different pathways. The strong negative correlated between them will lead to underestimation of the effects on risk of either pathway if confounding is not controlled.

Work stress, weight gain and weight loss: evidence for bidirectional effects of job strain on body mass index in the Whitehall II study

Previous research has focused on overall associations between work stress and body mass index (BMI) ignoring the possibility that stress may cause some people to eat less and lose weight and others to eat more. Using longitudinal data, we studied whether work stress induced weight loss in lean individuals and weight gain in overweight individuals. Prospective cohort study. A total of 7965 British civil servants (5547 men and 2418 women) aged 35-55 at study entry (The Whitehall II study). Work stress, indicated by the job strain model and measured as job control, job demands and job strain, was assessed at baseline and BMI at baseline and at 5-year follow-up. In men, the effect of job strain on weight gain and weight loss was dependent on baseline BMI (P</=0.03). In the leanest quintile (BMI<22 kg/m(2)) at baseline, high job strain and low job control were associated with weight loss by follow-up, whereas among those in the highest BMI quintile (>27 kg/m(2)), these stress indicators were associated with subsequent weight gain. No corresponding interaction was seen among women. Inconsistent findings reported by previous studies of stress and BMI have generally been interpreted to indicate the absence of an association. In light of our results, the possibility of differential effects of work stress should also be taken into account.

Obesity is a risk factor for dyspnea but not for airflow obstruction.

Previous research suggests that obesity is an important risk factor for asthma. However, since obesity can cause dyspnea through mechanisms other than airflow obstruction, diagnostic misclassification of asthma could partially account for this association. To determine whether there is a relationship between obesity and airflow obstruction. A total of 16 171 participants (17 years or older) from the Third National Health and Nutrition Examination Survey (NHANES III) were divided into 5 quintiles based on their body mass index (BMI) to determine the association between BMI quintile and risk of self-reported asthma, bronchodilator use, exercise performance, and airflow obstruction. Significant airflow obstruction was defined as a ratio less than 80% the predicted value of forced expiratory volume in 1 second to forced vital capacity adjusted for age, sex, and race. The highest BMI quintile (ie, the most obese participants) had the greatest risk of self-reported asthma (odds ratio [OR], 1.50; 95% confidence interval [CI], 1.24-1.81), bronchodilator use (OR, 1.94; 95% CI, 1.38-2.72), and dyspnea with exertion (OR, 2.66; 95% CI, 2.35-3.00). Paradoxically, the highest BMI quintile had the lowest risk for significant airflow obstruction (P =.001). This study demonstrates that while obesity is a risk factor for self-reported asthma, obese participants are at a lower risk for (objective) airflow obstruction. Many more obese than nonobese participants were using bronchodilators despite a lack of objective evidence for airflow obstruction. These data suggest that mechanisms other than airflow obstruction are responsible for dyspnea genesis in obesity and that asthma might be overdiagnosed in the obese population.

Abdominal and total adiposity and risk of coronary heart disease in men.

Waist circumference is a simpler measure of abdominal adiposity than waist/hip ratio (WHR), but few studies have directly compared the two measures as predictors of coronary heart disease (CHD) in men. In addition, whether the association of abdominal adiposity is independent of total adiposity as measured by body mass index (BMI) in men remains uncertain. To compare waist circumference and WHR as predictors of CHD in men, and to determine whether the association is independent of BMI. Prospective cohort study. We compared WHR, waist circumference and BMI with risk of CHD (myocardial infarction or coronary revascularization) among men in the Physicians' Health Study, a randomized trial of aspirin and beta-carotene among 22 071 apparently healthy US male physicians, aged 40-84 y at baseline in 1982. Men reported height at baseline, and weight, waist and hip measurements on the 9 y follow-up questionnaire. Among the 16 164 men who reported anthropometric measurements and were free from prior CHD, stroke or cancer, a total of 552 subsequent CHD events occurred during an average follow-up of 3.9 y. After adjusting for age, randomized study agent, smoking, physical activity, parental history of myocardial infarction, alcohol intake, multivitamin and aspirin use, men in the highest WHR quintile (>or=0.99) had a relative risk (RR) for CHD of 1.50 (95% CI 1.14-1.98) compared with those in the lowest quintile (<0.90). Men in the highest waist circumference quintile (>or=103.6 cm) had a RR of 1.60 (CI, 1.21-2.11) for CHD compared with men in the lowest quintile (<88.4 cm). Further adjustment for BMI substantially attenuated these associations: men in the highest WHR and waist circumference quintiles had relative risks for CHD of 1.23 (CI, 0.92-1.66) and 1.06 (CI, 0.74-1.53), respectively. Men in the highest BMI quintile (>or=27.6 kg/m(2)) had a multivariate RR of CHD of 1.73 (CI, 1.29-2.32), after adjustment for WHR. No significant effect modification by age of the relationship between either measure of abdominal adiposity and risk of CHD was observed. These data support a modest relationship between abdominal adiposity, as measured by either WHR or waist circumference, and risk of CHD both in middle-aged and older men. However, abdominal adiposity did not remain an independent predictor of CHD after adjustment for BMI.

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

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. Cross-sectional cohort study. Rural Pennsylvania. 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. 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. 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. 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.

Cutaneous malignant melanoma: association with height, weight and body-surface area. a prospective study in Norway.

To investigate whether anthropometric indices as body height, body-mass index (BMI) and body-surface area (BSA) have any influence on the risk of cutaneous malignant melanoma (CMM), we analyzed height and weight data from a Norwegian screening survey running between 1963 and 1975 and comprising 1.3 million individuals followed for 14 to 26 years. Among females, CMM was diagnosed in 2814 incident cases, while the number among males was 2144 during 22,988,345 person-years of follow-up. With adjustment for age, birth cohort, geographic region and BMI, the risk for CMM increased significantly with increasing quintiles of height in both sexes. The tallest persons were at greater relative risk than the shortest ones: 1.60 and 1.59 in males and females respectively. This positive association was also found for CMM localized on face and trunk in both sexes, and in the lower limbs only in females. Males in the highest quintile of BMI had a relative risk for CMM of 1.26 compared with the lowest quintile, while a non-significant negative association were found in obese females. This negative association increased and was significant for CMM located on the trunk and lower limbs in females. Among males we observed a consistent association between BSA and risk of CMM similar to that for height. These relationships between anthropometric indices and CMM are discussed according to factors which promote growth, among which nutrition, social class and hormones are the most important.

Potential for increasing high-density lipoprotein cholesterol, subfractions HDL 2-C and HDL 3-C, and apoprotein Al among middle-age women

Background. Studies have shown high-density lipoprotein cholesterol (HDL-C) to be a strong predictor of cardiovascular disease (CVD) risk. Methods. Determinants of HDL-C and apoprotein AI concentrations were evaluated cross-sectionally in 1987 among 429 women, ages 45–54, from a population-based study of CVD risk factors through menopause (the Healthy Women Study, University of Pittsburgh). Results. Subjects were healthy and not taking hormone replacement therapy. Results showed levels of HDL-C (mg/dl) to range from 23 to 117, HDL 2-C from 0 to 53, HDL 3-C from 16 to 66, and apoprotein AI from 87 to 204. Multivariate analyses which included age, cigarettes/day, alcohol intake (g/day), physical activity (Paffenbarger questionnaire), body mass index (BMI), and waist/hip ratio (WHR) showed that women who smoked ⩾ 20 cigarettes a day, reported little or no alcohol intake, expended less than 500 kcal/week, and were in the highest quintile of BMI and WHR had, on average, 33 mg/dl lower HDL-C than slender, nonsmoking women who drank moderately and exercised. HDL 2-C showed a similar pattern, whereas the HDL 3-C concentration had only a modest association with these factors. HDL-C was somewhat lower among women who had stopped menstruating than among premenopausal women. The apoprotein AI level was associated with alcohol intake (positively) and BMI (negatively). Conclusion. Theoretically, by raising their HDL-C by 10 mg/dl, women could reduce their CVD risk by as much as one-third (based on results from the Framingham Heart Study). As CVD is the leading cause of death among postmenopausal women, the potential impact of such a reduction in risk would be large.

The Effects of Non-Response in a Prospective Study of Cancer: 15-Year Follow-Up

Out of 11,136 Japanese men identified on the island of Oahu, Hawaii in 1965 by the Honolulu Heart Program, 8006 responded to a mailed questionnaire and were examined. Some 1871 responded only to the mailed questionnaire, and 1259 did not respond at all. After 15 years of follow-up, the examined men had significantly lower risk of death from all causes and death from cancer. Minor differences were also noted between the two groups in the risk of cancer of the lung, stomach, colon, and rectum. However, the examined men had a significantly higher risk of prostate cancer. In general, the strength of these non-response effects was mainly due to risk differences in the first five years of the 15-year follow-up period. The relative risk (RR) of each of the seven endpoint events tended towards 1.0 as each of the three successive five-year follow-up intervals were considered. An exception to this was the prostate cancer incidence RR which favoured the unexamined men throughout the entire 15 years, but significantly so only in the last five-year follow-up interval. When the 8006 examined and 1871 unexamined men who responded to the mailed questionnaire were evaluated with respect to the association of cigarette smoking with lung cancer incidence, the RR for smokers was 9.77 for the examined men, and 6.73 for the unexamined men. Since these RRs are not significantly different, there should be little bias in RR estimates of cigarette smoking for lung cancer if the observation was limited to only the examined men. With regard to the association of body mass index (BMI) with colon cancer in older men, the RRs for men in the highest BMI quintile were quite comparable, at 1.37 for the examined group and 1.60 for the unexamined men. We conclude that although some non-response effects on cancer incidence exist in this cohort, they do not appear to be serious enough to have changed conclusions drawn about risk relationships.