Body mass index in early and mid-adulthood, and subsequent mortality: a historical cohort study

Risk assessment of obesity-related noncommunicable diseases through body mass index trajectories in adulthood: NHANES 2007-2018

AIM

To assess the impact of adult body mass index (BMI) trajectories on the risk of obesity-related noncommunicable diseases (NCDs) in the U.S. adults after adjustment for sociodemographic and lifestyle factors.

METHODS

Data were extracted from the National Health and Nutrition Examination Survey conducted from 2007 to 2018, including male and female participants aged 29-59 years. Rao-Scott adjusted chi-square was employed to detect associations between categorical variables in descriptive analyses. Cox proportional hazards models estimated hazard ratios (HR) and 95% confidence intervals (CI) for NCDs and BMI trajectories, adjusted for sociodemographic and lifestyle factors. Kaplan-Meier curves illustrated the cumulative incidence over time.

RESULTS

Analyses were carried out on 15 721 participants and revealing significant differences among BMI trajectories in terms of demographic, lifestyle, and health characteristics. The overall prevalence of NCDs was 28.0% (95%CI:26.6-28.9). The cumulative incidence over time was higher in the high increase, moderate increase, and mixed trajectory groups, with a correspondingly higher cumulative risk (p < 0.001). Non-overweight trajectory was considered reference category in Cox models. The BMI trajectories were independently associated with an increased risk of NCDs, even after adjusting for potential confounders (HR: 1.7; 95%CI: 1.4-1.9 for moderate increase; HR: 3.6; 95%CI: 3.2-4.1 for high increase; and HR: 2.4; 95%CI: 2.1-2.7, for mixed). Furthermore, differences between males and females were also observed.

CONCLUSION

The transition to and persistence of obesity into adulthood increases the risk of NCDs. The implementation of targeted interventions with long-term monitoring of BMI may be beneficial in the prevention of future obesity-related NCDs.

Effects of personal and interpersonal factors on changes of food choices and physical activity among college students

BACKGROUND

Health behaviors developed in the college years tend to persist in adulthood. However, distinct changing patterns of food choices and physical activity (PA) and their predictors are still less clear among college students. The current study sought to explore changes of food choices and PA, as well as the effects of personal and interpersonal factors.

METHOD

Two-wave longitudinal data was collected from a sample of 431 Chinese college students (Mean baseline age = 19.15 ± 0.61 years; 45.7% male). A validated self-reported food frequency questionnaire was used to assess the frequency of food choices. The Chinese revised version of physical activity rating scale was used to assess physical activity. Latent profile analysis, latent transition analysis, and multinomial logistic regression analysis were used to analyze the data.

RESULTS

Two profiles of food choices, i.e., Avoiding staples (5.1% at Time 1) and Varied diet (94.9% at Time 1), were identified at both timepoints. 90.9% remained the same profiles over time, 63.6% participants in the Avoiding staples profile shifted to the Varied diet profile, and only 6.3% of those in the Varied diet profile shifted to the Avoiding staples profile. Negative body shape-related belief was related to the translation from the Varied diet profile to the Avoiding staples profile. Further, four profiles of PA, i.e., Inactives (51.0% at Time 1), Low activies (26.0% at Time 1), Moderate activies (15.3% at Time 1), and Activies (7.7% at Time 1), were identified at both timepoints. 50.8% remained the same profiles over time, 38.6% Inactivies shifted to the other profiles, and 48.5% Activies shifted to the other profiles over time. Participants with higher self-efficacy showed an increase in PA over time, and those with lower self-efficacy and lower peer support showed a decrease in PA over time.

CONCLUSIONS

Overall, most of college students remained the same food choices profiles, and body shape-related belief contributed to changes in food choices profiles. About half of college students experienced changes in PA, and the predictors of such changes were peer support and self-efficacy. The findings extend the understanding of the personal and interpersonal predictors of health behaviors among college students from a dynamic perspective.

Glucose Intolerance in Pregnancy and Offspring Obesity in Late Adolescence

OBJECTIVE

Gestational hyperglycemia is associated with deleterious neonatal outcomes, but long-term risks for offspring obesity are less clear. We estimated the odds for offspring adolescent overweight and obesity among mothers with gestational glucose intolerance.

RESEARCH DESIGN AND METHODS

In a mother-offspring historical cohort, the Israel military conscription data set was linked to a large health maintenance organization. Included were women who were evaluated at adolescence and underwent two-step gestational diabetes screening (mean age, 31 years) with a 50-g glucose challenge test (GCT), followed by a 100-g oral glucose tolerance test (OGTT) if the result was abnormal. Glucose tolerance categories included gestational normoglycemia, abnormal GCT with normal OGTT, impaired glucose tolerance (IGT; one abnormal OGTT value), and gestational diabetes. The primary outcome was offspring overweight/obesity (BMI ≥85th percentile) at adolescence, measured prior to military conscription. Logistic regression models were applied.

RESULTS

Of 33,482 mother-offspring pairs, overweight and obesity were observed in 6,516 offspring. Across increasing categories of pregnancy glycemia, the proportions of offspring with adolescent overweight/obesity increased: normoglycemia, 19%; abnormal GCT with normal OGTT, 22%; gestational IGT, 24%; and gestational diabetes, 25% (P < 0.0001). Corresponding odds ratios after adjustment for the mother's late adolescent characteristics (sociodemographic confounders and BMI) and pregnancy age were 1.2 (95% CI 1.1-1.4), 1.3 (1.2-1.5), and 1.4 (1.3-1.6), respectively. Further adjustment for offspring birth weight percentile and sociodemographic variables did not materially change results. Associations were more pronounced with increasing obesity severity.

CONCLUSIONS

Gestational glucose intolerance, including categories not meeting the gestational diabetes threshold, was associated with increased odds for offspring overweight/obesity at late adolescence.

Adolescent Blood Pressure and the Risk for Early Kidney Damage in Young Adulthood

BACKGROUND

Recent guidelines classified blood pressure above 130/80 mm Hg as hypertension. However, outcome data were lacking.

OBJECTIVE

To determine the association between blood pressure in adolescence and the risk for early kidney damage in young adulthood.

METHODS

In this nationwide cohort study, we included 629 168 adolescents aged 16 to 20 who underwent medical examinations before mandatory military service in Israel. We excluded 30 466 adolescents with kidney pathology, hypertension, or missing blood pressure or anthropometric data at study entry. Blood pressure measurements at study entry were categorized according to the Clinical Practice Guideline for Screening and Management of High Blood Pressure in Children and Adolescents: group A (<120/<80 mm Hg; Reference group), group B (120/<80-129/<80 mm Hg), group C (130/80-139/89 mm Hg), and group D (≥140/90 mm Hg). Early kidney damage in young adulthood was defined as albuminuria of ≥30 mg/g with an estimated glomerular filtration rate of 60 mL/(min·1.73 m²) or over.

RESULTS

Of 598 702 adolescents (54% men), 2004 (0.3%) developed early kidney damage during a mean follow-up of 15.1 (7.2) years. The adjusted hazard ratios for early kidney damage in blood pressure group C were 1.17 (1.03-1.32) and 1.51 (1.22-1.86) among adolescents with lean (body mass index <85th percentile) and high body mass index (body mass index ≥85th percentile), respectively. Corresponding hazard ratios for kidney disease in group D were 1.49 (1.15-1.93) and 1.79 (1.35-2.38) among adolescents with lean and high body mass index, respectively.

CONCLUSIONS

Blood pressure of ≥130/80 mm Hg was associated with early kidney damage in young adulthood, especially in adolescents with overweight and obesity.

Adolescent body mass index and changes in pre-pregnancy body mass index in relation to risk of gestational diabetes

BACKGROUND

Pregestational excessive body mass index (BMI) is linked to an increased risk for gestational diabetes mellitus (GDM), but less is known on the effect of adolescent BMI on GDM occurrence. The study aimed to investigate possible associations of adolescent BMI and changes in BMI experienced before first pregnancy, with gestational diabetes risk.

METHODS

This retrospective study was based on linkage of a military screening database of adolescent health status (Israel Defence Forces) including measured height and weight, with medical records (Maccabi Healthcare Services, MHS) of a state-mandated health provider. The latter covers about 25% of the Israeli population; about 90% of pregnant women undergo screening by the two-step Carpenter-Coustan method. Adolescent BMI was categorized according to Center of Disease Control and Prevention percentiles. Only first documented pregnanies were analyzed and GDM was the outcome.

FINDINGS

Of 190,905 nulliparous women, 10,265 (5.4%) developed GDM. Incidence proportions of GDM were 5.1%, 6.1%, 7.3%, and 8.9% among women with adolescent normal BMI, underweight, overweight, and obesity (p<0.001), respectively. In models that accounted for age at pregnancy, birth year, and sociodemographic variables, the adjusted odd ratios (aORs) for developing GDM were: 1.2 (95%CI, 1.1-1.3), 1.5 (1.4-1.6), and 1.9 (1.7-2.1) for adolescent underweight, overweight, and obesity (reference group, normal BMI). Adolescent BMI tracked with BMI notes in the pre-pregnancy period (r=63%). Resuming normal pre-pregnancy BMI from overweight or obesity in adolescence diminished GDM risk, but this diminished risk was not observed among those who returned to a normal per-pre-pregnancy BMI from being underweight in adolescence. Sustained overweight or obesity conferred an aOR for developing GDM of 2.5 (2.2-2.7); weight gain from adolescent underweight and normal BMI to pre-pregnancy excessive BMI conferred aORs of 3.1 (1.6-6.2) and 2.6 (2.2-2.7), respectively.

INTERPRETATION

Change in BMI status from adolescence to pre-pregnancy may contribute to GDM risk. Identifying at-risk populations is important for early preventive interventions.

FUNDING

None.

Weight Change Since Age 20 and the Risk of Cardiovascular Disease Mortality: A Prospective Cohort Study

Aim: Weight change could have many health outcomes. This study aimed to investigate the association between weight change and mortality risk due to total cardiovascular disease (CVD), ischemic heart disease (IHD), and stroke among Japanese.

Methods: We used Suita Study data from 4,746 people aged 30-79 years in this prospective cohort study. Weight change was defined as the difference between baseline weight and weight at age 20. We used Cox proportional hazards models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) of total CVD, IHD, and stroke mortality for 1) participants with a weight change (＞10, 5 to 10, -5 to -10, and ＜-10 kg) compared to those with stable weight (-4.9 to 4.9 kg) and 2) participants who moved from one body mass index category (underweight, normal weight, or overweight) to another compared to those with normal weight at age 20 and baseline.

Results: Within a median follow-up period of 19.9 years, the numbers of total CVD, IHD, and stroke mortality were 268, 132, and 79, respectively. Weight loss of ＞10 kg was associated with the increased risk of total CVD mortality 2.07 (1.29, 3.32) and stroke mortality 3.02 (1.40, 6.52). Moving from normal weight at age 20 to underweight at baseline was associated with the increased risk of total CVD, IHD, and stroke mortality: 1.76 (1.12, 2.77), 2.10 (1.13, 3.92), and 2.25 (1.05, 4.83), respectively.

Conclusion: Weight loss, especially when moving from normal to underweight, was associated with the increased risk of CVD mortality.

Roles of CA19-9 in pancreatic cancer: Biomarker, predictor and promoter

Carbohydrate antigen 19-9 (CA19-9) is the best validated biomarker and an indicator of aberrant glycosylation in pancreatic cancer. CA19-9 functions as a biomarker, predictor, and promoter in pancreatic cancer. As a biomarker, the sensitivity is approximately 80%, and the major challenges involve false positives in conditions of inflammation and nonpancreatic cancers and false negatives in Lewis-negative Individuals. Lewis antigen status should be determined when using CA19-9 as a biomarker. CA19-9 has screening potential when combined with symptoms and/or risk factors. As a predictor, CA19-9 could be used to assess stage, prognosis, resectability, recurrence, and therapeutic efficacy. Normal baseline levels of CA19-9 are associated with long-term survival. As a promoter, CA19-9 could be used to evaluate the biology of pancreatic cancer. CA19-9 can accelerate pancreatic cancer progression by glycosylating proteins, binding to E-selectin, strengthening angiogenesis, and mediating the immunological response. CA19-9 is an attractive therapeutic target for cancer, and strategies include therapeutic antibodies and vaccines, CA19-9-guided nanoparticles, and inhibition of CA19-9 biosynthesis.

Overweight and Risk of Noncommunicable Diseases in Adulthood: An Analysis of NHANES IV 2015-2016

BACKGROUND

Worldwide, overweight is one of the main risk factors for Noncommunicable Diseases (NCDs). In this scenario, Body Mass Index (BMI) is the main tool to assess nutritional status of the adult population.

AIM

To analyze the association between overweight and the risk of developing type 2 diabetes Mellitus (T2DM) and/or high blood pressure (HBP) during adulthood.

SUBJECTS AND METHODS

We used data of subjects aged between 30-64 years old from the United States National Survey of Health and Nutrition Examination (2015-2016). We calculated the risk of developing T2DM and/or HBP in adulthood using a Log-Binomial Regression model. We included sampling weights in our analysis and we adjusted it for confounding factors.

RESULTS

We evaluated a total of 2,666 individuals. Overweight affected around 38% of the sample when they were 25 years old and around 70% during the interview. We found 4 factors (overweight, smoking, sedentary lifestyle, and age) that were positively associated with the development of T2DM and/or HBP. Long-term overweight more than doubles the risk of developing these diseases [RR = 2.44; 95%CI: 1.92-3.09].

CONCLUSION

The incidence of T2DM and/or HBP were positively associated with the overweight in adulthood. These results suggest that the prevention of overweight could decrease NCDs prevalence into adulthood.

Fatty fish intake in mothers during pregnancy and in their children in relation to the development of obesity and overweight in childhood: The prospective ABIS study

BACKGROUND

Although controversial, lower maternal intake of n-3 polyunsaturated fatty acid (PUFA) during pregnancy and lower levels of omega-3 PUFA in serum phospholipids during childhood have been related to obesity. The main source of omega-3 PUFA is fatty fish in the diet.

OBJECTIVES

To assess the relationship between overweight/obesity and the intake of fatty fish in maternal diet during pregnancy and in children up to 8 years of age.

METHODS

The prospective cohort All Children in South-East Sweden (ABIS) followed babies from birth to 8 years of age. A total of 6749 children at 5 years of age (boys 52.6%) and 3017 children at 8 years (boys 52.3%) participated. A "fatty-fish index" was constructed on the basis of self-reports of nutritional habits.

RESULTS

The prevalence of overweight and obesity in children at 5 years were 12.9% and 4.2%, respectively. At 8 years, 12.2% of the children presented overweight and 2.3% obesity. Girls were more affected than boys by overweight/obesity. A higher fish index during pregnancy was not related to overweight/obesity in the children, whereas a higher fish index in the children during the first years of life was related to obesity at 5 and 8 years of age. This relationship disappeared in a multivariable analysis. Maternal body mass index (BMI), maternal education, maternal smoking during pregnancy, birth weight, and physical activity all remained related to overweight/obesity at both 5 and 8 years of age.

CONCLUSION

No relationships were found between a lower intake of fatty fish in the diet, neither in mothers during pregnancy nor in early childhood, and increased risk of overweight/obesity.

American Indian, Alaska Native, Native Hawaiian, and Pacific Islander Children's Body Mass Index: Diminished Returns of Parental Education and Family Income

Background

Socioeconomic status (SES) is associated with several health-related outcomes, such as obesity and body mass index (BMI). However, we do not know whether SES is associated differently with children's BMI from American Indian and Alaska Native and Native Hawaiian and Pacific Islander (AIAN/NHPI) families when compared to non-Hispanic White (NHW) families.

Aim

To compare AIAN/NHPI and NHW families for associations between parental education, family income, and children's BMI in the United States (U.S).

Methods

This cross-sectional investigation used the Adolescent Brain Cognitive Development (ABCD) study data. Participants (n = 8580) included 63 AIAN/NHPI and 8517 NHW children between ages 9 and 10. The independent variables were parental education and family income. The primary outcome was BMI. Race was the moderator. Age, sex, and family structure were covariates. Mixed-effects regression models were used for data analysis.

Results

In the pooled sample, higher parental education and family income were associated with lower children's BMI. We found interactions between race and parental education and family income indicating weaker associations between parental education and family income and children's BMI in AIAN/NHPI families than in NHW families.

Conclusion

The salience of parental education and family income as social determinants of children's BMI is diminished for AIAN/NHPI families than NHW families. As a result, AIAN/NHPI children with high SES remain at risk for high BMI, while high-SES NHW children show the lowest BMI. Future research should test if obesogenic environments, food options, and physical activity-friendly neighborhoods can explain higher-than-expected BMI in high-SES AIAN/NHPI children. In other terms, more research is needed to understand if residential segregation, discrimination, and historical trauma explain the observed differences in the social patterning of childhood BMI in AIAN/NHPI and NHW communities.

Weight change across adulthood in relation to all cause and cause specific mortality: prospective cohort study

OBJECTIVE

To investigate the association between weight changes across adulthood and mortality.

DESIGN

Prospective cohort study.

SETTING

US National Health and Nutrition Examination Survey (NHANES) 1988-94 and 1999-2014.

PARTICIPANTS

36 051 people aged 40 years or over with measured body weight and height at baseline and recalled weight at young adulthood (25 years old) and middle adulthood (10 years before baseline).

MAIN OUTCOME MEASURES

All cause and cause specific mortality from baseline until 31 December 2015.

RESULTS

During a mean follow-up of 12.3 years, 10 500 deaths occurred. Compared with participants who remained at normal weight, those moving from the non-obese to obese category between young and middle adulthood had a 22% (hazard ratio 1.22, 95% confidence interval 1.11 to 1.33) and 49% (1.49, 1.21 to 1.83) higher risk of all cause mortality and heart disease mortality, respectively. Changing from obese to non-obese body mass index over this period was not significantly associated with mortality risk. An obese to non-obese weight change pattern from middle to late adulthood was associated with increased risk of all cause mortality (1.30, 1.16 to 1.45) and heart disease mortality (1.48, 1.14 to 1.92), whereas moving from the non-obese to obese category over this period was not significantly associated with mortality risk. Maintaining obesity across adulthood was consistently associated with increased risk of all cause mortality; the hazard ratio was 1.72 (1.52 to 1.95) from young to middle adulthood, 1.61 (1.41 to 1.84) from young to late adulthood, and 1.20 (1.09 to 1.32) from middle to late adulthood. Maximum overweight had a very modest or null association with mortality across adulthood. No significant associations were found between various weight change patterns and cancer mortality.

CONCLUSIONS

Stable obesity across adulthood, weight gain from young to middle adulthood, and weight loss from middle to late adulthood were associated with increased risks of mortality. The findings imply that maintaining normal weight across adulthood, especially preventing weight gain in early adulthood, is important for preventing premature deaths in later life.

Changes in midlife fitness, body mass index, and smoking influence cancer incidence and mortality: A prospective cohort study in men

Cancer prevention efforts include modification of unhealthy lifestyle, such as smoking cessation and resisting gain in body weight. Although physical activity is inversely related to risk of several cancers, it is poorly studied whether changes in physical activity or fitness influence future cancer risk. Thus, we aimed to investigate whether changes in midlife cardiorespiratory fitness (CRF), body mass index (BMI), and smoking habits influence cancer incidence and mortality. The study cohort includes 1689 initially healthy men, aged 40-59 years. Measurements of CRF, BMI and information on smoking habits were collected in two repeated waves, 7 years apart. Cox regression models estimated associations as hazard rates (HR) with 95% confidence intervals (CI), between midlife changes in the modifiable lifestyle factors and cancer incidence and mortality. The men were followed prospectively for more than 30 years. Compared to CRF loss (>5%), improved CRF (>5%) was associated with lower cancer incidence (HR 0.81, 95% CI 0.67-0.98) and mortality (HR 0.70, 95% CI 0.54-0.92), and maintaining the CRF stable yielded lower cancer incidence (HR 0.76, 95% CI 0.61-0.95). No association was seen for BMI gain, but maintaining the BMI stable was related to lower cancer incidence (HR 0.77, 95% CI 0.60-0.98), compared to BMI loss. Continue smoking was associated with higher cancer incidence and mortality, compared to men who stopped smoking. In particular, this study adds new knowledge about the potential preventive role of CRF in cancer development and emphasizes lifestyle modification as a highly important effort in cancer prevention.

The Impact of Childhood and Adolescent Obesity on Cardiovascular Risk in Adulthood: a Systematic Review

PURPOSE OF REVIEW

Adult obesity and cardiovascular diseases are closely linked. Yet, the relationship of childhood and adolescent obesities with cardiovascular diseases in adulthood requires additional evidence. The goal of the review is to inspect the relationship between childhood- and adolescent-increased body mass index (BMI) and cardiovascular risk factors, fatal and non-fatal cardiovascular diseases in adulthood.

RECENT FINDINGS

Cardiovascular diseases in adulthood are linked by most of the studies to childhood and adolescent obesities. Studies showed that childhood and adolescent obesities increased the incidence of cardiovascular disease risk factors and were linked to higher risk of cardiovascular morbidity and mortality in adulthood. Childhood and adolescent obesities were also associated, likely with a causal relationship, with an increased likelihood for various cardiovascular morbidities including ischemic heart disease, stroke, but also non-ischemic heart disease-related cardiac pathologies.

The association between BMI and mortality using early adulthood BMI as an instrumental variable for midlife BMI

The article aims to describe the association between midlife body mass index (BMI) and cardiovascular disease (CVD)- and all-cause mortality, and to use early adulthood BMI as an instrumental variable for midlife BMI, in order to obtain an estimate less distorted by midlife confounders and reverse causality. Data from Norwegian health surveys (1974–2003) (midlife BMI, smoking, blood pressure, total cholesterol, heart rate), Military Conscription Records, National Tuberculosis Screenings (early adulthood BMI), National Educational Registry and Cause of Death Registry were linked. Participants with data on BMI in early adulthood and midlife were included (n = 148.886). Hazard Ratio (HR) for CVD mortality was higher in men with midlife obesity relative to normal weight (HR = 1.46(95% CI 1.25, 1.70). For all-cause mortality, HR was higher in those with obesity or underweight in midlife relative to normal weight (Men:HR = 1.19(95% CI 1.09, 1.29), HR = 2.49(95% CI 1.81, 3.43) Women:HR = 1.33(95% CI 1.13, 1.56), HR = 1.61(95% CI 1.22, 2.13)). In instrumental variable analyses, increased BMI became more strongly associated with CVD and all-cause mortality, and the increased risk of all-cause mortality among the underweight attenuated.

Body Mass Index and Kidney Disease-Related Mortality in Midlife: A Nationwide Cohort of 2.3 Million Adolescents

OBJECTIVE

This study aimed to evaluate the association of body mass index (BMI) in adolescence with mortality attributed to kidney disease.

METHODS

In this study, 2,294,139 Jewish Israeli adolescents with measured weight and height at 17 years old during the military fitness assessment were analyzed with a follow-up extending up to 45 years. All kidney-related outcomes, coded by the Central Bureau of Statistics from death notifications as the underlying cause of death, were obtained by linkage. Cox hazards models were applied.

RESULTS

During 42,297,007 person-years of follow-up (median 18.4 years), 226 deaths related to kidney disease were recorded. There was an increased risk for kidney-related death among adolescents with overweight and obesity with adjusted hazard ratios of 2.7 (95% CI: 1.8-3.9) and 8.4 (5.1-13.8), respectively, with BMI between 18.5 and 22.0 kg/m² as the reference. A 15% increased risk for kidney-related mortality (1.11-1.19) per unit increment in BMI was observed. Furthermore, a multivariable spline model indicated a minimum risk for kidney-related mortality starting at BMI of 18.6 kg/m² with significantly increased risk seen above values of 22.8 kg/m² . The results withstood extensive sensitivity analyses, including stratification of kidney-related death attributed to acute, chronic, and total kidney disease.

CONCLUSIONS

Adolescent overweight and obesity are risk markers for kidney-related mortality over 4 decades.

Change in Weight and Body Mass Index Associated With All-Cause Mortality in Korea: A Nationwide Longitudinal Study

CONTEXT

Many studies have reported conflicting evidence on the association between weight change and mortality.

OBJECTIVE

We investigated the association between weight change and subsequent all-cause mortality, using a large-scale, population-based cohort from the National Health Insurance System health checkup data between 2005 and 2015.

METHODS

A total of 11,524,763 subjects older than age 20 years were included. Weight was measured every 2 years and weight change over 4 years was divided into eight categories, from weight loss ≥15% to weight gain ≥20%, for every 5% of weight change. The hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality were analyzed using multivariable Cox proportional hazard models compared with the stable weight group (weight change <5%) after adjusting for age, sex, smoking, drinking, exercise, diabetes mellitus, hypertension, dyslipidemia, cancer, and income.

RESULTS

Weight loss was associated with increased mortality rates compared with weight gain; the group with weight loss ≥15% had the highest HR for all-cause mortality (HR, 2.598; 95% CI, 2.537 to 2.659). The HR for all-cause mortality in the ≥20% weight gain group was 1.784 (95% CI, 1.695 to 1.877). Across all body mass index (BMI) categories, weight loss ≥15% was associated with increased mortality rates and the highest mortality rates were found in the BMI ≥30 kg/m2 group (HR, 3.469; 95% CI, 2.236 to 5.381).

CONCLUSIONS

Weight change over 4 years showed a reverse J-shaped all-cause mortality curve, independent of BMI status. Weight loss was associated with a greater risk of mortality than was weight gain.

Adolescent Body Mass Index and Cardiovascular Disease-Specific Mortality by Midlife

CONTEXT

As opposed to coronary heart disease (CHD) mortality, cardiovascular mortality attributed to non-CHD causes has increased.

OBJECTIVE

To evaluate the association of body mass index (BMI) in late adolescence with mortality attributed to non-CHD cardiovascular sequelae.

DESIGN AND SETTING

A nationwide cohort.

PARTICIPANTS

A total of 2,294,139 adolescents examined between 1967 and 2010.

INTERVENTIONS

Height and weight were measured at age 17. All cardiovascular disease-specific outcomes, coded by the Central Bureau of Statistics from death notifications as the underlying cause of death, were obtained by linkage. Cox hazards models were applied.

MAIN OUTCOME MEASUREMENTS

Death attributed to fatal arrhythmias, hypertensive heart disease, cardiomyopathies, arterial disease, heart failure, and pulmonary embolism.

RESULTS

During 42,297,007 person-years of follow-up, there were 3178 deaths due to cardiovascular causes, of which 279, 122, 121, 114, 94, and 70 were attributed to the main outcomes, respectively. BMI was positively associated with all study outcomes with hazard ratios (HRs) per unit increment in BMI ranging from 1.09 [95% confidence interval (CI): 1.03 to 1.16] for arterial disease to 1.16 (95% CI: 1.11 to 1.21) for hypertensive heart disease. When BMI was treated as a categorical variable, a graded increase in risk was evident from the high-normal (22.0 to <25.0 kg/m2) to the overweight to the obese categories, with HRs of 1.4, 1.7, and 3.7 for arrhythmias; 1.9, 4.1, and 8.0 for hypertensive heart disease; 1.5, 2.4, and 4.0 for cardiomyopathies, 2.7, 5.0, and 3.5; for arterial disease, 1.7, 2.7, and 5.4 for heart failure; and 1.3, 1.8, and 3.0 for pulmonary embolism. Findings persisted in extensive sensitivity analyses.

CONCLUSIONS

Adolescent BMI within the accepted normal range is associated with non-CHD nonstroke cardiovascular outcomes.

Association between excessive BMI increase during puberty and risk of cardiovascular mortality in adult men: a population-based cohort study

BACKGROUND

Being overweight during childhood and adolescence is associated with increased risk of cardiovascular disease in adulthood, but the relative contribution of prepubertal childhood BMI and BMI change during puberty to adult mortality due to cardiovascular disease is unknown. We assessed the contribution of these two distinct developmental BMI parameters for cardiovascular mortality in adult men.

METHODS

As a part of the ongoing population-based BMI Epidemiology Study (BEST) in Gothenburg, Sweden, men born between 1945 and 1961 with information on both their childhood BMI at age 8 years and BMI change during puberty were included in the study and followed up until December, 2013. Participants who died or emigrated before age 20 years were excluded from the analysis. BMI was collected from paediatric growth charts and mandatory military conscription tests. Childhood overweight (BMI of ≥17·9 kg/m²) was defined according to the Centers for Disease Control and Prevention's cutoff at 8 years of age, and BMI change during puberty was defined as the difference between young adult BMI and childhood BMI (BMI at age 20 years minus BMI at age 8 years). Information on mortality was retrieved from high quality national registers with the participants' ten-digit personal identity number. We used Cox proportional hazard regression to analyse the association between exposures and mortality. The ethics committee of the University of Gothenburg, Sweden, approved the study and waived the requirement for written informed consent.

FINDINGS

We followed 37 672 Swedish men from age 20 years for a mean of 37·8 years (1 422 185 person-years follow-up). 3188 all-cause deaths and 710 cardiovascular deaths occurred during follow-up. The correlation between childhood BMI and BMI change during puberty was marginal (r=0·06). BMI change during puberty, but not childhood BMI, was independently associated with adult all-cause and cardiovascular mortality in men. Boys that became overweight during puberty (HR 2·39; 95% CI 1·86-3·09) and boys who were overweight consistently throughout childhood and puberty (1·85; 1·28-2·67), but not boys overweight in childhood that normalised during puberty (0·99, 0·65-1·50), had increased risk of cardiovascular mortality compared with participants who were not overweight in childhood or as young adults. The association between BMI change during puberty and cardiovascular mortality was non-linear with a substantial association above a threshold of 6·7 units increase in BMI.

INTERPRETATION

Excessive BMI increase during puberty is a risk marker of adult cardiovascular mortality. These results indicate that BMI should be monitored during puberty to identify boys with increased risk of adult cardiovascular mortality.

FUNDING

Swedish Research Council, the Swedish Government (under the Avtal om Läkarutbildning och Medicinsk Forskning [Agreement for Medical Education and Research]), the Lundberg Foundation, the Torsten Söderberg Foundation, the Novo Nordisk Foundation, the Knut and Alice Wallenberg Foundation, and the Anna Ahrenberg Foundation.

BMI at Age 17 Years and Diabetes Mortality in Midlife: A Nationwide Cohort of 2.3 Million Adolescents

OBJECTIVE

The sequelae of increasing childhood obesity are of major concern. We assessed the association of BMI in late adolescence with diabetes mortality in midlife.

RESEARCH DESIGN AND METHODS

The BMI values of 2,294,139 Israeli adolescents (age 17.4 ± 0.3 years), measured between 1967 and 2010, were grouped by U.S. Centers for Disease Control and Prevention age/sex percentiles and by ordinary BMI values. The outcome, obtained by linkage with official national records, was death attributed to diabetes mellitus (DM) as the underlying cause. Cox proportional hazards models were applied.

RESULTS

During 42,297,007 person-years of follow-up (median, 18.4 years; range <1-44 years) there were 481 deaths from DM (mean age at death, 50.6 ± 6.6 years). There was a graded increase in DM mortality evident from the 25th to the 49th BMI percentile group onward and from a BMI of 20.0-22.4 kg/m² onward. Overweight (85th to 94th percentiles) and obesity (the 95th percentile or higher), compared with the 5th to 24th percentiles, were associated with hazard ratios (HRs) of 8.0 (95% CI 5.7-11.3) and 17.2 (11.9-24.8) for DM mortality, respectively, after adjusting for sex, age, birth year, height, and sociodemographic variables. The HR for the 50th through 74th percentiles was 1.6 (95% CI 1.1-2.3). Findings persisted in a series of sensitivity analyses. The estimated population-attributable fraction for DM mortality, 31.2% (95% CI 26.6-36.1%) for the 1967-1977 prevalence of overweight and obesity at age 17, rose to a projected 52.1% (95% CI 46.4-57.4%) for the 2012-2014 prevalence.

CONCLUSIONS

Adolescent BMI, including values within the currently accepted "normal" range, strongly predicts DM mortality up to the seventh decade. The increasing prevalence of childhood and adolescent overweight and obesity points to a substantially increased future adult DM burden.

Body-Mass Index in 2.3 Million Adolescents and Cardiovascular Death in Adulthood

BACKGROUND

In light of the worldwide increase in childhood obesity, we examined the association between body-mass index (BMI) in late adolescence and death from cardiovascular causes in adulthood.

METHODS

We grouped data on BMI, as measured from 1967 through 2010 in 2.3 million Israeli adolescents (mean age, 17.3±0.4 years), according to age- and sex-specific percentiles from the U.S. Centers for Disease Control and Prevention. Primary outcomes were the number of deaths attributed to coronary heart disease, stroke, sudden death from an unknown cause, or a combination of all three categories (total cardiovascular causes) by mid-2011. Cox proportional-hazards models were used.

RESULTS

During 42,297,007 person-years of follow-up, 2918 of 32,127 deaths (9.1%) were from cardiovascular causes, including 1497 from coronary heart disease, 528 from stroke, and 893 from sudden death. On multivariable analysis, there was a graded increase in the risk of death from cardiovascular causes and all causes that started among participants in the group that was in the 50th to 74th percentiles of BMI (i.e., within the accepted normal range). Hazard ratios in the obese group (≥95th percentile for BMI), as compared with the reference group in the 5th to 24th percentiles, were 4.9 (95% confidence interval [CI], 3.9 to 6.1) for death from coronary heart disease, 2.6 (95% CI, 1.7 to 4.1) for death from stroke, 2.1 (95% CI, 1.5 to 2.9) for sudden death, and 3.5 (95% CI, 2.9 to 4.1) for death from total cardiovascular causes, after adjustment for sex, age, birth year, sociodemographic characteristics, and height. Hazard ratios for death from cardiovascular causes in the same percentile groups increased from 2.0 (95% CI, 1.1 to 3.9) during follow-up for 0 to 10 years to 4.1 (95% CI, 3.1 to 5.4) during follow-up for 30 to 40 years; during both periods, hazard ratios were consistently high for death from coronary heart disease. Findings persisted in extensive sensitivity analyses.

CONCLUSIONS

A BMI in the 50th to 74th percentiles, within the accepted normal range, during adolescence was associated with increased cardiovascular and all-cause mortality during 40 years of follow-up. Overweight and obesity were strongly associated with increased cardiovascular mortality in adulthood. (Funded by the Environment and Health Fund.).

A Mobile Health Lifestyle Program for Prevention of Weight Gain in Young Adults (TXT2BFiT): Nine-Month Outcomes of a Randomized Controlled Trial

Background

The unprecedented rise in obesity among young adults, who have limited interaction with health services, has not been successfully abated.

Objective

The objective of this study was to assess the maintenance outcomes of a 12-week mHealth intervention on prevention of weight gain in young adults and lifestyle behaviors at 9 months from baseline.

Methods

A two-arm, parallel, randomized controlled trial (RCT) with subjects allocated to intervention or control 1:1 was conducted in a community setting in Greater Sydney, Australia. From November 2012 to July 2014, 18- to 35-year-old overweight individuals with a body mass index (BMI) of 25-31.99 kg/m2 and those with a BMI ≥ 23 kg/m2 and a self-reported weight gain of ≥ 2 kg in the past 12 months were recruited. A 12-week mHealth program “TXT2BFiT” was administered to the intervention arm. This included 5 coaching calls, 96 text messages, 12 emails, apps, and downloadable resources from the study website. Lifestyle behaviors addressed were intake of fruits, vegetables, sugar-sweetened beverages (SSBs), take-out meals, and physical activity. The control group received 1 phone call to introduce them to study procedures and 4 text messages over 12 weeks. After 12 weeks, the intervention arm received 2 further coaching calls, 6 text messages, and 6 emails with continued access to the study website during 6-month follow-up. Control arm received no further contact. The primary outcome was weight change (kg) with weight measured at baseline and at 12 weeks and self-report at baseline, 12 weeks, and 9 months. Secondary outcomes were change in physical activity (metabolic equivalent of task, MET-mins) and categories of intake for fruits, vegetables, SSBs, and take-out meals. These were assessed via Web-based surveys.

Results

Two hundred and fifty young adults enrolled in the RCT. Intervention participants weighed less at 12 weeks compared with controls (model β=−3.7, 95% CI −6.1 to −1.3) and after 9 months (model β=− 4.3, 95% CI − 6.9 to − 1.8). No differences in physical activity were found but all diet behaviors showed that the intervention group, compared with controls at 9 months, had greater odds of meeting recommendations for fruits (OR 3.83, 95% CI 2.10-6.99); for vegetables (OR 2.42, 95% CI 1.32-4.44); for SSB (OR 3.11, 95% CI 1.47-6.59); and for take-out meals (OR 1.88, 95% CI 1.07-3.30).

Conclusions

Delivery of an mHealth intervention for prevention of weight gain resulted in modest weight loss at 12 weeks with further loss at 9 months in 18- to 35-year-olds. Although there was no evidence of change in physical activity, improvements in dietary behaviors occurred, and were maintained at 9 months. Owing to its scalable potential for widespread adoption, replication trials should be conducted in diverse populations of overweight young adults.

Trial Registration

Australian and New Zealand Clinical Trials Registry (ANZCTR): ACTRN12612000924853; (Archived by WebCite at http://www.webcitation.org/6i6iRag55)

Ion Channels in Obesity: Pathophysiology and Potential Therapeutic Targets

Obesity is a multifactorial disease related to metabolic disorders and associated with genetic determinants. Currently, ion channels activity has been linked to many of these disorders, in addition to the central regulation of food intake, energetic balance, hormone release and response, as well as the adipocyte cell proliferation. Therefore, the objective of this work is to review the current knowledge about the influence of ion channels in obesity development. This review used different sources of literature (Google Scholar, PubMed, Scopus, and Web of Science) to assess the role of ion channels in the pathophysiology of obesity. Ion channels present diverse key functions, such as the maintenance of physiological homeostasis and cell proliferation. Cell biology and pharmacological experimental evidences demonstrate that proliferating cells exhibit ion channel expression, conductance, and electrical properties different from the resting cells. Thereby, a large variety of ion channels has been identified in the pathogenesis of obesity such as potassium, sodium, calcium and chloride channels, nicotinic acetylcholine receptor and transient receptor potential channels. The fundamental involvement of these channels on the generation of obesity leads to the progress in the knowledge about the mechanisms responsible for the obesity pathophysiology, consequently emerging as new targets for pharmacological modulation.

Longitudinal Study of Body Mass Index in Young Males and the Transition to Fatherhood

Despite a growing understanding that the social determinants of health have an impact on body mass index (BMI), the role of fatherhood on young men's BMI is understudied. This longitudinal study examines BMI in young men over time as they transition from adolescence into fatherhood in a nationally representative sample. Data from all four waves of the National Longitudinal Study of Adolescent Health supported a 20-year longitudinal analysis of 10,253 men beginning in 1994. A "fatherhood-year" data set was created and changes in BMI were examined based on fatherhood status (nonfather, nonresident father, resident father), fatherhood years, and covariates. Though age is positively associated with BMI over all years for all men, comparing nonresident and resident fathers with nonfathers reveals different trajectories based on fatherhood status. Entrance into fatherhood is associated with an increase in BMI trajectory for both nonresident and resident fathers, while nonfathers exhibit a decrease over the same period. In this longitudinal, population-based study, fatherhood and residence status play a role in men's BMI. Designing obesity prevention interventions for young men that begin in adolescence and carry through young adulthood should target the distinctive needs of these populations, potentially improving their health outcomes.

Pediatric obesity. An introduction

The prevalence of child and adolescent obesity in the United States increased dramatically between 1970 and 2000, and there are few indications that the rates of childhood obesity are decreasing. Obesity is associated with myriad medical, psychological, and neurocognitive abnormalities that impact children's health and quality of life. Genotypic variation is important in determining the susceptibility of individual children to undue gains in adiposity; however, the rapid increase in pediatric obesity prevalence suggests that changes to children's environments and/or to their learned behaviors may dramatically affect body weight regulation. This paper presents an overview of the epidemiology, consequences, and etiopathogenesis of pediatric obesity, serving as a general introduction to the subsequent papers in this Special Issue that address aspects of childhood obesity and cognition in detail.

Association of changes in fitness and body composition with cancer mortality in men

INTRODUCTION

Both baseline cardiorespiratory fitness and adiposity predict the risk of cancer mortality. However, the effects of changes in these two factors over time have not been evaluated thoroughly. The aim of this study was to examine the independent and joint associations of changes in cardiorespiratory fitness and body composition on cancer mortality.

METHODS

The cohort consisted of 13,930 men (initially cancer-free) with two or more medical examinations from 1974 to 2002. Cardiorespiratory fitness was assessed by a maximal treadmill exercise test, and body composition was expressed by body mass index (BMI) and percent body fat. Changes in cardiorespiratory fitness and body composition between the baseline and the last examination were classified into loss, stable, and gain groups.

RESULTS

There were 386 deaths from cancer during an average of 12.5 yr of follow-up. After adjusting for possible confounders and BMI, change hazard ratios (95% confidence intervals) of cancer mortality were 0.74 (0.57-0.96) for stable fitness and 0.74 (0.56-0.98) for fitness gain. Inverse dose-response relationships were observed between changes in maximal METs and cancer mortality (P for linear trend = 0.05). Neither BMI change nor percent body fat change was associated with cancer mortality after adjusting for possible confounders and maximal METs change. In the joint analyses, men who became less fit had a higher risk of cancer mortality (P for linear trend = 0.03) compared with those who became more fit, regardless of BMI change levels.

CONCLUSIONS

Being unfit or losing cardiorespiratory fitness over time was found to predict cancer mortality in men. Improving or maintaining adequate levels of cardiorespiratory fitness appears to be important for decreasing cancer mortality in men.

Overweight in early adulthood, adult weight change, and risk of type 2 diabetes, cardiovascular diseases, and certain cancers in men: a cohort study

The relative importance of overweight after childhood and excess weight gain during adulthood remains unclear. In 39,909 male participants of the Health Professionals Follow-Up Study who were 40-75 years of age in 1986 and were followed until 2008, we documented 8,755 incident cases of obesity-related chronic diseases (type 2 diabetes mellitus, cardiovascular diseases, and colorectal, renal, pancreatic, and esophageal cancers). We calculated composite and cause-specific hazard ratios using a model that included body mass index (BMI; weight (kg)/height (m)(2)) at 21 years of age, weight change since age 21 years, smoking, alcohol consumption, and family histories of myocardial infarction, colon cancer, and diabetes. Compared with a BMI at 21 years of 18.5-22.9, the composite hazard ratio for a BMI of 23-24.9 was 1.22 (95% confidence interval (CI): 1.16, 1.29), that for a BMI of 25.0-27.4 was 1.57 (95% CI: 1.48, 1.67), that for a BMI of 27.5-29.9 was 2.40 (95% CI: 2.17, 2.65), and that for a BMI ≥30.0 was 3.15 (95% CI: 2.76, 3.60). The composite hazard ratios for adult weight gain compared with a stable weight were 1.12 (95% CI: 1.03, 1.22) for a gain of 2.5-4.9 kg, 1.41 (95% CI: 1.31, 1.52) for a gain of 5-9.9 kg, 1.72 (95% CI: 1.59, 1.86) for a gain of 10-14.9 kg, and 2.45 (95% CI: 2.27, 2.63) for a gain ≥15 kg. Adiposity in early adulthood and adult weight gain were both associated with marked increases in the risk of major chronic diseases in middle-aged and older men, and these associations were already apparent at modest levels of overweight and weight gain.

Body mass and weight change in adults in relation to mortality risk

Using data from the National Institutes of Health-AARP Diet and Health Study, we evaluated the influence of adulthood weight history on mortality risk. The National Institutes of Health-AARP Diet and Health Study is an observational cohort study of US men and women who were aged 50-71 years at entry in 1995-1996. This analysis focused on 109,947 subjects who had never smoked and were younger than age 70 years. We estimated hazard ratios of total and cause-specific mortality for recalled body mass index (BMI; weight (kg)/height (m)(2)) at ages 18, 35, and 50 years; weight change across 3 adult age intervals; and the effect of first attaining an elevated BMI at 4 successive ages. During 12.5 years' follow-up through 2009, 12,017 deaths occurred. BMI at all ages was positively related to mortality. Weight gain was positively related to mortality, with stronger associations for gain between ages 18 and 35 years and ages 35 and 50 years than between ages 50 and 69 years. Mortality risks were higher in persons who attained or exceeded a BMI of 25.0 at a younger age than in persons who reached that threshold later in adulthood, and risks were lowest in persons who maintained a BMI below 25.0. Heavier initial BMI and weight gain in early to middle adulthood strongly predicted mortality risk in persons aged 50-69 years.

Body mass index and mortality among blacks and whites adults in the Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial

OBJECTIVE

In a large prospective cohort, we examined the relationship of body mass index (BMI) with mortality among blacks and compared the results to those among whites in this population.

DESIGN AND METHODS

The study population consisted of 7,446 non-Hispanic black and 130,598 white participants, ages 49-78 at enrollment, in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial. BMI at baseline, BMI at age 20, and BMI change were calculated using self-reported and recalled height and weight. Relative risks were stratified by race and sex and adjusted for age, education, marital status, and smoking.

RESULTS

During follow-up, 1,495 black and 18,236 white participants died (mean = 13 years). Clear J-shaped associations between BMI and mortality were observed among white men and women. Among black men and women, the bottoms of these curves were flatter, and increasing risks of death with greater BMI were observed only at higher BMI levels (≥35.0). Associations for BMI at age 20 and BMI change also appeared to be stronger in magnitude in whites versus blacks, and these racial differences appeared to be more pronounced among women.

CONCLUSION

Our results suggest that BMI may be more weakly associated with mortality in blacks, particularly black women, than in whites.

Modeling obesity histories in cohort analyses of health and mortality

There is great interest in understanding the role of weight dynamics over the life cycle in predicting the incidence of disease and death. Beginning with a Medline search, we identify, classify, and evaluate the major approaches that have been used to study these dynamics. We identify four types of models: additive models, duration-of-obesity models, additive-weight-change models, and interactive models. We develop a framework that integrates the major approaches and shows that they are often nested in one another, a property that facilitates statistical comparisons. Our criteria for evaluating models are two-fold: the model's interpretability and its ability to account for observed variation in health outcomes. We apply two sets of nested models to data on adults age 50-74 years at baseline in two national probability samples drawn from National Health and Nutrition Examination Survey. One set of models treats obesity as a dichotomous variable and the other treats it as a continuous variable. In three of four applications, a fully interactive model does not add significant explanatory power to the simple additive model. In all four applications, little explanatory power is lost by simplifying the additive model to a duration model in which the coefficients of weight at different ages are set equal to one another. Other versions of a duration-of-obesity model also perform well, underscoring the importance of obesity at early adult ages for mortality at older ages.

Obesity in young men, and individual and combined risks of type 2 diabetes, cardiovascular morbidity and death before 55 years of age: a Danish 33-year follow-up study

OBJECTIVES

To examine the association between body mass index (BMI) in young adulthood and cardiovascular risks, including venous thromboembolism, before 55 years of age.

DESIGN

Cohort study using population-based medical databases.

SETTING

Outcomes registered from all hospitals in Denmark from 1977 onwards.

PARTICIPANTS

6502 men born in 1955 and eligible for conscription in Northern Denmark.

MAIN OUTCOME MEASURES

Follow-up began at participants' 22nd birthday and continued until death, emigration or 55 years of age, whichever came first. Using regression analyses, we calculated the risks and HRs, adjusting for cognitive test score and years of education.

RESULTS

48% of all obese young men (BMI ≥30 kg/m(2)) were either diagnosed with type 2 diabetes, hypertension, myocardial infarction, stroke or venous thromboembolism or died before reaching 55 years of age. Comparing obese men with normal weight men (BMI 18.5 to <25.0 kg/m(2)), the risk difference for any outcome was 28% (95% CI 19% to 38%) and the HR was 3.0 (95% CI 2.3 to 4.0). Compared with normal weight, obesity was associated with an event rate that was increased more than eightfold for type 2 diabetes, fourfold for venous thromboembolism and twofold for hypertension, myocardial infarction and death.

CONCLUSIONS

In this cohort of young men, obesity was strongly associated with adverse cardiometabolic events before 55 years of age, including venous thromboembolism. Compared with those of normal weight, young obese men had an absolute risk increase for type 2 diabetes, cardiovascular morbidity or premature death of almost 30%.

Body mass index at age 25 and all-cause mortality in whites and African Americans: the Atherosclerosis Risk in Communities study

PURPOSE

Approximately 20% of young adults in the United States are obese, and most of them gain weight between young and middle adulthood. Few studies have examined the association between elevated body mass index (BMI) in early adulthood and mortality or have examined that such effects are independent of changes in weight. To our knowledge, no such study has been conducted in African-American samples.

METHODS

We used data from 13,941 African-American and white adults who self-reported their weight at the age of 25, and had weight and height measured when they were 45-64 years of age (1987-1989). Date of death was ascertained between 1987 and 2005. Hazard ratios and hazard differences for the effects of BMI at age 25 on all-cause mortality were determined using Cox proportional hazard and additive hazard models, respectively.

RESULTS

In the combined ethnic-gender groups, the hazard ratio associated with a 5 kg/m(2) increase in BMI at age 25 was 1.28 (95% confidence interval [CI]: 1.22-1.35), and the hazard difference was 2.75 (2.01-3.50) deaths/1,000 person-years. Associations were observed in all four ethnic-gender groups. Models including weight change from age 25 to age in 1987-1989 resulted in null estimates for BMI in African-American men, whereas associations were maintained or only mildly attenuated in other ethnic-gender groups.

CONCLUSIONS

Excess weight during young adulthood should be avoided because it contributes to increases in death rates that may be independent of changes in weight experienced in later life. Further study is needed to better understand these associations in African-American men.

Association of body mass index in early adulthood and middle age with future site-specific cancer mortality: the Harvard Alumni Health Study

BACKGROUND

The association between adiposity in early adulthood and subsequent development of specific malignancies is unclear. Further, the potential for mediation by adiposity in middle age has not been well examined. In a rare study, we investigated the association of body mass index (BMI) in early adulthood with mortality from several site-specific cancers.

DESIGN

In the Harvard Alumni Health Study cohort, 19 593 males had a physical examination at the university between 1914 and 1952 (mean age: 18.4 years) and returned a questionnaire in 1962 or 1966 (mean age = 45.1 years). BMI was computed using weight (kg)/height(2) (m(2)) at both time points. Vital status follow up continued for a maximum of 82 years.

RESULTS

Positive early adulthood cancer mortality gradients by BMI were found for all malignancies combined (adjusted hazard ratio [HR] = 1.11; 95% confidence interval [CI]: 1.05-1.17 for a one standard deviation increase in early adulthood BMI), and for lung (HR = 1.24; 95% CI = 1.10-1.40) and skin (HR = 1.29; 95% CI = 0.96-1.75) cancers. There were also apparent associations for cancers of the oesophagus and urogenital sites. Mediation by BMI in middle age was found to be minimal.

CONCLUSION

Higher BMI in early adulthood appears to be a direct risk factor for selected malignancies several decades later.

Body mass index in a large cohort of patients assigned to age decades between <20 and ≥80 years: relationship with cardiovascular morbidity and medication

OBJECTIVE

There is an ongoing debate about the relationship between obesity and morbidity in the elderly, the clinical relevance of overweight and obesity in older patients and the need or harms of treatment. The main purpose of our study was to investigate whether a higher BMI is associated with a worse cardiovascular risk in all age groups, especially in the older ones.

SUBJECTS AND DESIGN

We performed a retrospective evaluation of clinical data from 3926 patients who visited a medical outdoor center for diagnostic and/or therapeutic interventions in the period from January 1995 to July 2010. Patients were assigned to eight age groups of one decade from <20 years to ≥80 years.

RESULTS

The Body Mass Index (BMI) of our patients showed a continuous increase with increasing age with peak values in the age decade 61-70 years (26.29 ±4.42 kg/m2). This was paralleled by an increase in cardiovascular events and need for continuous medication, demonstrating peak values in the age decade 61-70 years (22.3% in the female and 24.7% in the male group). In all age decades up to 80 years the BMI values were higher in patients with events compared to those without it. multivariable linear regression analysis - including confounding variables (blood pressure, fasting glucose, HDL-cholesterol, triglycerides, physical activity, smoking) - revealed for all age groups a strong positive relation of BMI and a negative relation of fat free mass (FFM) to the probability for a cardiovascular event and need for medication.

CONCLUSION

In all age groups, the percentage of cardiovascular events was directly correlated with the BMI. Having in mind the transition to an aging society, therapeutic and preventive strategies should, therefore, include weight management strategies also for the elderly.

Body weight, weight perceptions and food intake patterns. A cross-sectional study among male recruits in the Norwegian National Guard

Background

Young men tend to have a low intake of vegetables and fruit. Unfortunately, this group is difficult to reach with health information. Furthermore, knowledge about weight perceptions and the relationship to food behaviour among young men is scant. The purpose of this study was to explore the relationship between BMI, health and weight perceptions and food intake patterns among young men in the military.

Methods

Data were collected with a 4-day food diary among 578 male recruits (age 18-26, mean 19.7) in the Norwegian National Guard (response rate 78%), in addition to a questionnaire, including questions about health and weight perceptions, and food frequency when still living at home. Weight and height were objectively measured. Food patterns were explored with principal component analysis, based on the diary data. A multivariate linear regression analysis determined the association between BMI and food patterns, and attitudes to health and slenderness, adjusting for smoking, physical activity and phase of data collection.

Results

Twenty eight percent of the recruits were overweight/obese (BMI > 25 kg/m²). Two-thirds meant that it is important for them to be slender, and these recruits reported more of both light (p = 0.025) and hard (p = 0.016) physical activity than the others. It was a positive association between the recruits' food frequency at home, and the amount of intake in the military camp for several food items. A principal component analysis identified three distinct food patterns, loading on 1) plant foods, 2) fast food/soft drinks, 3) milk/cereals. Those who stated that it is important for them to be slender, or to have good health, did not have significantly different food intake patterns than the others. BMI was inversely related to scores on the plant food pattern, and positive attitudes to slenderness.

Conclusion

The majority of the recruits find it important to be slender. This orientation had a bearing on their physical activity pattern, but less on the food intake pattern. The data also indicate that subjects with high intakes of plant foods were less likely to have a high BMI than others. It is important to raise awareness of healthy eating in young men.

Lifelong doubling of mortality in men entering adult life as obese

BACKGROUND

The association between obesity in adults and excess morbidity and mortality is well established, but the impact of being obese in early adulthood on health throughout adult life needs elucidation. We investigated the all-cause mortality until 80 years of age in men starting adult life as obese.

METHODS

Among 362,200 Danish young men, examined for military service between 1943 and 1977, all obese (defined as body mass index (BMI ≥ 31.0 kg m(-2)), and, as controls, a random 1% sample of the remaining population were identified. A total of 1862 obese, corresponding to all men above the 99.5 percentile in this population, and 3476 controls were included, at a median age of 19 years (range: 18-25 years of age). They were followed until 2007 and Cox regression models were used to estimate the mortality in the obese relative to the controls. In addition, two reference groups were used: normal weight men (BMI: 18.5-24.9 kg m(-2)) and the men with the lowest mortality in this cohort (BMI: 22.0-24.9 kg m(-2)).

RESULTS

During the 65 years of follow-up, 1191 men died. At all ages from 18 to 80 years, the mortality in the obese was twice that of the controls (hazard ratio (HR): 2.10; 95% confidence interval (CI): 1.84-2.39). The median survival proportion (0.5) was reached about 8 years earlier in the obese than in either of the reference groups. Relative to the normal weight and men with the lowest mortality HRs of 2.14 (95% CI: 1.86-2.45) and 2.38 (95% CI: 2.00-2.85), respectively, were estimated for the obese. Neither year of birth nor education significantly influenced the excess mortality.

CONCLUSION

Men entering adult life as obese experience a lifelong doubling of mortality, a finding that strongly supports the continued need to avoid beginning adult life as obese.

Differential association of anthropometric parameters with coronary risk in women--data of the CORA study

OBJECTIVE

The predictive value of weight gain, BMI, waist circumference (WC) and waist-to-hip ratio (WHR) as to cardiovascular risk factors and coronary heart disease (CHD) is still controversial.

METHODS

200 consecutive pre- and postmenopausal women with incident CHD (cases) were compared with 255 randomized age-matched population-based controls recruited from corresponding neighborhoods of Hamburg between 1997 and 2001.

RESULTS

At the time of recruitment cases and controls did not differ in BMI, but at any BMI in WC and WHR. Both parameters of central obesity were related to coronary risk. However, after adjustment for conventional risk factors, the odds ratio of WC for CHD lost its significance while the odds ratio of WHR was still 2.20 per 0.1 unit (95% confidence interval 1.48-3.27; p = 0.0001). The pattern of weight gain differed considerably in women with WHR ≥0.85 or <0.85 and closely matched that of women with or without CHD. The dietary pattern did not distinguish women with elevated WC or WHR.

CONCLUSION

In women, an elevated WHR was closely associated with the risk for CHD independent of BMI and conventional risk factors over and above an elevated WC. An increased WC predominantly seems to reflect the presence of components of the metabolic syndrome.

Trajectories of overweight and body mass index in adulthood and blood pressure at age 53: the 1946 British birth cohort study

OBJECTIVE

To assess the relationship between patterns of overweight during adulthood and systolic (SBP) and diastolic (DBP) blood pressure (BP) at age 53.

METHOD

Data are from 3035 male and female participants of the 1946 British birth cohort study. Body mass index (BMI) was obtained at ages 20, 26, 36, 43 and 53 years. Censored regression models accounting for medication were used to investigate associations of BP at 53 years with overweight (BMI > 25 kg/m) at each age, age at first overweight and conditional weight gain. Sex interactions were also examined.

RESULTS

Overweight at all ages except for 20 years in men was positively associated with BP at 53 years. After adjusting for current BMI, only overweight at age 43 contained additional information on BP in men. Men who were overweight at age 26 had a SBP 8.7 mmHg higher [95% confidence interval (CI) 4.4-13.0] than those first overweight at 53 years. Similar patterns but smaller associations were seen in women [P(interaction) < 0.001). All periods of adult weight gain (26-36, 36-43, 43-53 years) were associated with a higher BP. BMI tracked strongly through adulthood, the BMI at 53 years in men first overweight at 26 was 30.9 kg/m (95% CI 30.5-31.4) compared to 26.4 (95% CI 26.3-26.6) in those first overweight at age 53.

CONCLUSIONS

Early adult overweight and all periods of adult weight gain irrespective of earlier BMI were associated with higher BPs. This highlights the importance for later health of preventing overweight in early adulthood.

Long-term impact of overweight and obesity in childhood and adolescence on morbidity and premature mortality in adulthood: systematic review

BACKGROUND AND OBJECTIVE

The last systematic review on the health consequences of child and adolescent obesity found little evidence on consequences for adult health. The present study aimed to summarize evidence on the long-term impact of child and adolescent obesity for premature mortality and physical morbidity in adulthood.

METHODS

Systematic review with evidence searched from January 2002 to June 2010. Studies were included if they contained a measure of overweight and/or obesity between birth and 18 years (exposure measure) and premature mortality and physical morbidity (outcome) in adulthood.

RESULTS

Five eligible studies examined associations between overweight and/or obesity, and premature mortality: 4/5 found significantly increased risk of premature mortality with child and adolescent overweight or obesity. All 11 studies with cardiometabolic morbidity as outcomes reported that overweight and obesity were associated with significantly increased risk of later cardiometabolic morbidity (diabetes, hypertension, ischaemic heart disease, and stroke) in adult life, with hazard ratios ranging from 1.1-5.1. Nine studies examined associations of child or adolescent overweight and obesity with other adult morbidity: studies of cancer morbidity were inconsistent; child and adolescent overweight and obesity were associated with significantly increased risk of later disability pension, asthma, and polycystic ovary syndrome symptoms.

CONCLUSIONS

A relatively large and fairly consistent body of evidence now demonstrates that overweight and obesity in childhood and adolescence have adverse consequences on premature mortality and physical morbidity in adulthood.

What is the predictive value of established risk factors for total and cardiovascular disease mortality when measured before middle age? Pooled analyses of two prospective cohort studies from Scotland

AIMS

To examine the association of physiological, behavioural and social characteristics in pre-middle age with future total and cardiovascular disease (CVD) mortality.

METHODS AND RESULTS

Risk factor data on 1503 individuals aged 16-35 years at baseline were collected in two prospective cohort studies using standard protocols. Their association with total and CVD mortality ascertained during 40 years of follow-up was summarized using Cox proportional hazards regression. A median follow-up of 39.6 years gave rise to 255 deaths (103 from CVD). In age-adjusted and sex-adjusted analyses, impaired lung function [one standard deviation increases in forced expiratory volume in 1 s: hazards ratio 0.69; 95% confidence interval 0.55, 0.86; and in forced vital capacity: 0.76; 0.59, 0.98], current cigarette smoking (4.16; 2.22, 7.80) and higher alcohol consumption (one standard deviation increase in standard units consumed: 1.20; 1.02, 1.41) were associated with CVD. In fully adjusted analyses associations generally held. For total mortality, these factors and obesity and socioeconomic disadvantage were predictive.

CONCLUSION

A range of risk factors measured before middle age were related to risk of total and CVD mortality up to four decades later, indicating that public health interventions should be implemented earlier in the life course than is currently the case.

Effectiveness of thigh-to-thigh current path for the measurement of abdominal fat in bioelectrical impedance analysis

We present a new method measuring body impedance using a thigh-to-thigh current path, which can reflect the abdominal fat portion more sensitively and can be conveniently applied during the daily use on a toilet seat. Two pairs of electrodes were installed on a toilet seat to provide current and to permit voltage measurement through a thigh-to-thigh current path. The effectiveness of the method was compared with conventional foot-to-foot and hand-to-foot current paths by simulation and by experiments referenced to computed tomography (CT) image analysis. Body impedance using three different current paths was measured, and abdominal CT images were acquired for eight subjects. Measured body impedances were compared with the visceral to subcutaneous fat ratio (VF/SF) calculated from the CT-determined abdominal fat volume. The thigh-to-thigh current path was about 75% more sensitive in abdominal fat measurement than the conventional current paths in simulation experiments and displayed a higher VF/SF correlation (r = 0.768) than the foot-to-foot (r = 0.425) and hand-to-foot (r = 0.497) current paths.

Mortality attributable to obesity among middle-aged adults in the United States

Obesity is considered a major cause of premature mortality and a potential threat to the longstanding secular decline in mortality in the United States. We measure relative and attributable risks associated with obesity among middle-aged adults using data from the Health and Retirement Study (1992-2004). Although class II/III obesity (BMI > or = or = 35.0 kg/m2) increases mortality by 40% in females and 62% in males compared with normal BMI (BMI = 18.5-24.9), class I obesity (BMI = 30.0-34.9) and being overweight (BMI = 25.0-29.9) are not associated with excess mortality. With respect to attributable mortality, class II/III obesity (BMI > or = 35.0) is responsible for approximately 4% of deaths among females and 3% of deaths among males. Obesity is often compared with cigarette smoking as a major source of avoidable mortality. Smoking-attributable mortality is much larger in this cohort: about 36% in females and 50% in males. Results are robust to confounding by preexisting diseases, multiple dimensions of socioeconomic status (SES), smoking, and other correlates. These findings challenge the viewpoint that obesity will stem the long-term secular decline in U.S. mortality.

Increases in body mass index over a 7-year period and risk of cause-specific mortality in Korean men

BACKGROUND

The association between increased body mass index (BMI) and subsequent mortality remains unclear in Asians. This study investigated the associations between BMI increases and cause-specific mortality in middle-aged Korean men.

METHODS

We conducted a retrospective cohort study of 473 358 Korean men aged 30-64 years, who had undergone health examinations in both 1992 and 1998 and were followed up during 1998-2004. Cox proportional hazards for cause-specific 7-year mortality in relation to BMI changes after stratification of baseline BMI status were analysed.

RESULTS

Mortality from cardiovascular disease (CVD) was associated with BMI in both 1992 and 1998. Non-CVD mortality was inversely associated with BMI in both 1992 and 1998. We cross-classified participants into groups based on their baseline BMI levels and percent BMI changes during follow-up; men with the lowest BMI level at baseline (BMI in 1992 <21 kg/m(2)) and stable BMI during follow-up (percent change in BMI <5%) were included in the reference category. Compared with the reference group, CVD mortality was higher in initially obese men (BMI in 1992 > or =25 kg/m(2)) with any increase of BMI, and in initially lean men (BMI in 1992 <21 kg/m(2)) or initially overweight men (BMI in 1992 23-24.9 kg/m(2)) with BMI increases of > or =10%. BMI increases of 5.0-9.9% in men with baseline BMI <25 kg/m(2) and stable BMI in men with baseline BMI > or =21 kg/m(2) appeared to lower the risk for non-CVD or all-cause mortality, to below the levels seen in the reference group.

CONCLUSIONS

Among middle-aged Korean men, obesity or severe weight gain was detrimental to CVD mortality. An increase in BMI appeared to have a predictive value for CVD mortality, especially when used in combination with baseline BMI level. In contrast, moderate weight gain in non-obese men seemed to protect against non-CVD and all-cause mortality.

Is body mass index before middle age related to coronary heart disease risk in later life? Evidence from observational studies

Objective

Although obesity beginning early in life is becoming more common, its implications for coronary heart disease (CHD) risk in later life remain uncertain. We examined the relationship of body mass index (BMI) before 30 years of age to CHD risk in later life.

Design

Systematic review of published studies relating BMI between age 2-30 years to later CHD risk. Studies were identified using Medline (1950 onwards), Embase (1980 onwards) and Web of Science (1970 onwards) databases (to November 2007).

Measurements

Relative risks (RR) of CHD associated with a 1 standard deviation (SD) increase in BMI (most based on a narrow age-range at measurement) were extracted by 2 authors independently, and combined using random-effect models.

Results

Fifteen studies provided seventeen estimates (731,337 participants, 23,894 CHD events) of the association of early BMI to later CHD outcome. BMI in early childhood (2 to 6 years, 3 estimates) showed a weak inverse association with CHD risk (RR 0.94, 95% CI 0.82-1.07). BMI in later childhood (7 to <18 years, 7 estimates) and BMI in early adult life (18-30 years, 7 estimates) were both positively related to later CHD risk (RR 1.09, 95% CI 1.00-1.20; RR 1.19, 95% CI 1.11-1.29 respectively). However, there was considerable statistical heterogeneity between study estimates. Results were unaffected by adjustment for social class and/or cigarette smoking, blood pressure and/or total cholesterol, in studies with available data. Gender and year of birth (1900-1976) had little effect on the association.

Conclusions

BMI is positively related to CHD risk from childhood onwards; the associations in young adults are consistent with those observed in middle age. Long-term control of BMI from childhood may be important to reduce the risk of CHD.

Weight change in diabetes and glycemic and blood pressure control

OBJECTIVE

Weight loss in type 2 diabetes is undisputedly important, and data from community settings are limited. We evaluated weight change and resulting glycemic and blood pressure control in type 2 diabetic patients at an HMO.

RESEARCH DESIGN AND METHODS

Using electronic medical records, this retrospective cohort study identified 2,574 patients aged 21-75 years who received a new diagnosis of type 2 diabetes between 1997 and 2002. We estimated 3-year weight trajectories using growth curve analyses, grouped similar trajectories into four categories using cluster analysis, compared category characteristics, and predicted year-4 above-goal A1C and blood pressure by group.

RESULTS

The weight-trajectory groups were defined as higher stable weight (n = 418; 16.2%), lower stable weight (n = 1,542; 59.9%), weight gain (n = 300; 11.7%), and weight loss (n = 314; 12.2%). The latter had a mean weight loss of 10.7 kg (-9.8%; P < 0.001) by 18 months, with near-complete regain by 36 months. After adjusting for age, sex, baseline control, and related medication use, those with higher stable weight, lower stable weight, or weight-gain patterns were more likely than those who lost weight to have above-goal A1C (odds ratio [OR] 1.66 [95% CI 1.12-2.47], 1.52 [1.08-2.14], and 1.77 [1.15-2.72], respectively). Those with higher stable weight or weight-gain patterns were more likely than those who lost weight to have above-goal blood pressure (1.83 [1.31-2.57] and 1.47 [1.03-2.10], respectively).

CONCLUSIONS

A weight-loss pattern after new diagnosis of type 2 diabetes predicted improved glycemic and blood pressure control despite weight regain. The initial period postdiagnosis may be a critical time to apply weight-loss treatments to improve risk factor control.

Weight change and glycemic control after diagnosis of type 2 diabetes

BACKGROUND

Limited community-based data describe weight change after diabetes diagnosis.

OBJECTIVE

To evaluate weight change patterns and associations in the 1st year after diabetes mellitus type 2 diagnosis.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Patients aged 21-75 with diabetes mellitus type 2 diagnosed between 1 January 1997 and 31 December 2004, identified from electronic medical records in Kaiser Permanente Northwest, a health maintenance organization. Eligible patients met weight measurement criteria (a baseline and three additional weight measurements) and did not have a condition associated with unintentional weight change (n = 4,135).

MEASUREMENTS

We estimated 12-month patient weight trajectories using growth curve analyses, grouped similar trajectories using cluster analysis, and compared characteristics among groups.

RESULTS

The four weight trajectory groups were "higher stable weight" (n = 757; 18.3%), "lower stable weight" (n = 2,236; 54.1%), "weight gain" (n = 664; 16.0%), and "weight loss" (n = 478; 11.6%). After adjustments, members of the weight-loss group were more likely than those in the weight-gain group to be older, female, take fewer medications, have had nutritionist visits, and have a lower mean HbA(1c). Those in the weight-loss group were less likely to be in a race group at higher risk for obesity, have depression or dyslipidemia, or have taken >30 days of a sulfonylurea alone or with metformin.

CONCLUSIONS

A small-but-substantial group of patients had a mean weight trajectory that included a clinically significant weight loss. Weight-loss trajectories were strongly associated with better glycemic control when compared to weight gain. Patients with certain characteristics may need more support for weight loss.

Age and race impact the association between BMI and CVD mortality in women

OBJECTIVES

In previous studies, we have shown that obesity is associated with increased cardiovascular disease (CVD) mortality in white women but not in black women. Earlier research suggests that body mass index (BMI) has a greater effect on CVD mortality in younger white females than older white females, whereas this relationship in black women is not as clear. This study examines the effect of age on the association of BMI to CVD in black and white women.

METHODS

The Black Pooling Project includes data on 2,843 black women with 50,464 person-years of follow-up, and 12,739 white women with 214,606 person-years of follow-up. A Cox proportional hazards model was used to examine the association between BMI and CVD mortality for specific age/race groups. The younger group was < 60 years of age and the older group was > 60 years of age.

RESULTS

In younger white women, the relative risk (95% confidence interval [CI]) for CVD mortality was significant in obese women (BMI > 30 kg/m2) vs. women of normal weight (BMI 18.5-24.9 kg/m2) (1.59 [CI 1.20, 2.09]). Similarly, in older white women, the relative risk for CVD mortality in obese women vs. women of normal weight was significant (1.21 [CI 1.04, 1.41]). There were no such associations for black women. Overweight (BMI 25-29.9 kg/m2) was not associated with increased risk in black or white women.

CONCLUSION

These findings indicate that obesity is associated with a significantly greater risk of CVD mortality among white women, with the strongest association among white women < 60 years of age.