Body Mass Index In Young Adults Research Articles

Admixture/fine-mapping in Brazilians reveals a West African associated potential regulatory variant (rs114066381) with a strong female-specific effect on body mass and fat mass indexes.

Admixed populations are a resource to study the global genetic architecture of complex phenotypes, which is critical, considering that non-European populations are severely underrepresented in genomic studies. Here, we study the genetic architecture of BMI in children, young adults, and elderly individuals from the admixed population of Brazil. Leveraging admixture in Brazilians, whose chromosomes are mosaics of fragments of Native American, European, and African origins, we used genome-wide data to perform admixture mapping/fine-mapping of body mass index (BMI) in three Brazilian population-based cohorts from Northeast (Salvador), Southeast (Bambuí), and South (Pelotas). We found significant associations with African-associated alleles in children from Salvador (PALD1 and ZMIZ1 genes), and in young adults from Pelotas (NOD2 and MTUS2 genes). More importantly, in Pelotas, rs114066381, mapped in a potential regulatory region, is significantly associated only in females (p = 2.76e-06). This variant is rare in Europeans but with frequencies of ~3% in West Africa and has a strong female-specific effect (95% CI: 2.32-5.65 kg/m2 per each A allele). We confirmed this sex-specific association and replicated its strong effect for an adjusted fat mass index in the same Pelotas cohort, and for BMI in another Brazilian cohort from São Paulo (Southeast Brazil). A meta-analysis confirmed the significant association. Remarkably, we observed that while the frequency of rs114066381-A allele ranges from 0.8 to 2.1% in the studied populations, it attains ~9% among women with morbid obesity from Pelotas, São Paulo, and Bambuí. The effect size of rs114066381 is at least five times higher than the FTO SNPs rs9939609 and rs1558902, already emblematic for their high effects. We identified six candidate SNPs associated with BMI. rs114066381 stands out for its high effect that was replicated and its high frequency in women with morbid obesity. We demonstrate how admixed populations are a source of new relevant phenotype-associated genetic variants.

Effectiveness of Retro Walking and Forward Walking Treadmill Training on Abdominal Adiposity in Untrained Young Adults- AQuasi-experimental Study

Introduction: Retro walking or backward walking is an exercise mode which incurs an increased metabolic cost and results in a greater cardiopulmonary demand when compared to forward walking, while placing a lower stress on the joints of the lower limb. Abdominal adiposity, a part of metabolic syndrome, is an early risk-factor for morbidity and mortality in adulthood. Aim: The study aims to compare the effect of retro walking treadmill training and that of forward walking treadmill training, as potential modifiers of general obesity and abdominal obesity in untrained young adults. Materials and Methods: In this quasi experimental study, 111 untrained young men/young males aged 18-25 who were students of a medical university in Kingdom of Saudi Arabia were recruited and allocated randomly into two groups. One group underwent retro walking treadmill training five times a week for six weeks, and the other group underwent forward walking treadmill training for the same period. Waist-Hip Ratio (WHR), Waist- Height Ratio (WHtR) and Body Mass Index (BMI) were measured before and after the six-week intervention and subjected to statistical analysis. Results: There was a significant reduction in WHR and WHtR in the participants of the retro walking program when compared to participants of forward walking program. The decrease in BMI was not statistically significant. Conclusion: A retro walking training program is more effective in reducing BMI, WHR and WHtR in untrained young adults as compared to a forward walking program.

Differing Associations Between the Most Abundant Genera of the Fecal Microbiome and Sex, Fiber Intake Score, Stress, Stool Consistency and BMI in Healthy Young Adults

Abstract Objectives The objective of this secondary analysis was to characterize the relationships between the most abundant genera of the fecal microbiome and sex, fiber intake scores, stress, stool consistency and body mass index (BMI) in healthy young adults using data from the 1-week baseline period of a clinical study. Methods Data from a total of 182 participants (n = 120 female) with a mean age of 19.7 ± 0.1 y (mean ± SEM) and a healthy body mass index (BMI; 23.4 ± 0.3 kg/m2) were used. Participants self-reported stool consistency (Bristol stool score) as an estimate of gastrointestinal transit time and stress (0 = no stress to 10 = extremely stressed) daily for 1 week. The Rapid Eating Assessment-short questionnaire was completed at the end of baseline to assess intake frequency of fruits, vegetables and whole grains. The food frequency scores from the 3 food categories were summed for the fiber intake score. Microbial composition was determined by 16s rRNA sequencing of 1 stool sample provided during the baseline period. The top 15 genera, identified by % abundance of OTU reads, were selected for further analysis. Relationships between each of the genera and sex, fiber intake score, stress, stool consistency and BMI were assessed using a multiple linear regression model. Results The top 15 genera in descending % abundance were Bacteroides, Faecalibacterium, Dialister, Prevotella, Parabacteroides, Ruminococcus, Oscillospira, Sutterella, Phascolarctobacterium, Blautia, Bifidobacterium, Lachnospira, Roseburia, Eubacterium and Collinsella. The % abundance of Faecalibacterium was higher in men (P = 0.018) and was inversely related to intake of fiber containing foods (P = 0.034). Ruminococcus % abundance was inversely related to BMI (P = 0.020). Oscillospira % abundance was higher in women (P = 0.012) and decreased with increasing BMI (P = 0.024), stress (P = 0.032) and stool consistency score (i.e., looser stools; P = 0.027). Lachnospira % abundance increased with a increasing stool consistency score (P = 0.029) and with decreasing intake of fiber containing foods (P = 0.025). Conclusions These findings show differing associations between the most abundant genera of the fecal microbiome and sex, fiber intake score, stress, stool consistency and BMI in healthy young adults. Funding Sources Supported by Wakunaga of America Co., Ltd.

SAT-616 Associations Of Body Mass Index And Waist Circumference In Young Adulthood With Later Life Incident Diabetes

Background: Overweight and obesity are known risk factors for incident diabetes, but it remains unclear if exposures during young adulthood (age 18 to 39 years) contribute to mid and late-life (age ≥40 years, collectively labeled here as “later-life”) risk of incident diabetes independent of later-life risk factor exposures. Objective: We sought to assess the independent associations between young adult exposures to overweight and obesity, as assessed by body mass index (BMI) and waist circumference (WC), with later-life incident diabetes, accounting for later-life exposures. Methods: We pooled data from six US cohorts (ARIC, CARDIA, CHS, Framingham Offspring, Health ABC, and MESA), and imputed life-course risk factor trajectories for BMI and WC, as well as for multiple cardiometabolic risk factors, annually from age 18 years to end of follow-up for each participant. Incident diabetes was defined by observed fasting blood glucose ≥126 mg/dL, non-fasting glucose ≥200, or use of diabetes medications. We used Cox proportional hazards models to examine the independent associations between time-weighted average exposures to BMI and WC during young adulthood and incident diabetes. We also performed mediation analyses to assess whether these associations were mediated by young adult exposures to other cardiometabolic risk factors (blood pressure, lipids, insulin resistance). Results: 30,780 participants were included (mean age at first in-person visit 53.1±16.2 years; 56.1% female). Over a 9-year median follow-up, 4,323 participants had incident diabetes. Both young adult BMI and WC were associated with diabetes risk in a dose-dependent manner, independent of later-life BMI and WC. Compared to BMI 18.5–24.9 kg/m2, hazard ratios (HR) for incident diabetes were 1.27 (95%CI: 1.14–1.41) and 1.99 (95%CI: 1.67–2.37) for BMI 25–29 kg/m2 and ≥30 kg/m2, respectively. Similarly, compared to normal WC (≤80 cm women; ≤94 cm men), the HRs were 1.42 (95%CI: 1.26–1.59) for WC 81-88cm (women)/95-102cm (men) and 2.13 (95%CI: 1.87–2.43) for WC >88cm (women)/>102cm (men). Young adult homeostatic model of insulin resistance (HOMA-IR) mediated 49% (95%CI: 23–76) and 44% (95%CI: 26–62) of the association between young adult BMI and WC with later-life incident diabetes, respectively. Conclusions: Elevated BMI or WC during young adulthood were independently associated with later-life incident diabetes, after accounting for later-life BMI and WC, with insulin resistance suggested as a key mediator.

Young adulthood body mass index, adult weight gain and breast cancer risk: the PROCAS Study (United Kingdom)

BackgroundWe tested the hypothesis that body mass index (BMI) aged 20 years modifies the association of adult weight gain and breast cancer risk.MethodsWe recruited women (aged 47–73 years) into the PROCAS (Predicting Risk Of Cancer At Screening; Manchester, UK: 2009–2013) Study. In 47,042 women, we determined BMI at baseline and (by recall) at age 20 years, and derived weight changes. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for new breast cancer using Cox models and explored relationships between BMI aged 20 years, subsequent weight changes and breast cancer risk.ResultsWith median follow-up of 5.6 years, 1142 breast cancers (post-menopausal at entry: 829) occurred. Among post-menopausal women at entry, BMI aged 20 years was inversely associated [HR per SD: 0.87 (95% CI: 0.79–0.95)], while absolute weight gain was associated with breast cancer [HR per SD:1.23 (95% CI: 1.14–1.32)]. For post-menopausal women who had a recall BMI aged 20 years <23.4 kg/m2 (75th percentile), absolute weight gain was associated with breast cancer [HR per SD: 1.31 (95% CIs: 1.21–1.42)], but there were no associations for women with a recall BMI aged 20 years of >23.4 kg/m2 (Pinteraction values <0.05).ConclusionsAdult weight gain increased post-menopausal breast cancer risk only among women who were <23.4 kg/m2 aged 20 years.

Polygenic Risk, Fitness, and Obesity in the Coronary Artery Risk Development in Young Adults (CARDIA) Study

Obesity is a major determinant of disease burden worldwide. Polygenic risk scores (PRSs) have been posited as key predictors of obesity. How a PRS can be translated to the clinical encounter (especially in the context of fitness, activity, and parental history of overweight) remains unclear. To quantify the relative importance of a PRS, fitness, activity, parental history of overweight, and body mass index (BMI) (calculated as weight in kilograms divided by height in meters squared) in young adulthood on BMI trends over 25 years. This population-based prospective cohort study at 4 US centers included white individuals and black individuals with assessments of polygenic risk of obesity, fitness, activity, and BMI in young adulthood (in their 20s) and up to 25 years of follow-up. Data collected between March 1985 and August 2011 were analyzed from April 25, 2019, to September 29, 2019. Body mass index at the initial visit and 25 years later. This study evaluated an obesity PRS from a recently reported study of 1608 white individuals (848 women [52.7%]) and 909 black individuals (548 women [60.3%]) across the United States. At baseline (year 0), mean (SD) overall BMI was 24.2 (4.5), which increased to 29.6 (6.9) at year 25. Among white individuals, the PRS (combined with age, sex, self-reported parental history of overweight, and principal components of ancestry) explained 11.9% (at year 0) and 13.6% (at year 25) of variation in BMI. Although the addition of fitness increased the explanatory capability of the model (24.0% variance at baseline and up to 18.1% variance in BMI at year 25), baseline BMI in young adulthood was the strongest factor, explaining 52.3% of BMI in midlife in combination with age, sex, and self-reported parental history of overweight. Accordingly, models that included baseline BMI (especially BMI surveillance over time) were better in predicting BMI at year 25 compared with the PRS. In fully adjusted models, the effect sizes for fitness and the PRS on BMI were comparable in opposing directions. The added explanatory capacity of the PRS among black individuals was lower than among white individuals. Among white individuals, addition of baseline BMI and surveillance of BMI over time was associated with improved precision of predicted BMI at year 25 (mean error in predicted BMI 0 kg/m2 [95% CI, -11.4 to 11.4] to 0 kg/m2 [95% CI, -8.5 to 8.5] for baseline BMI and mean error 0 kg/m2 [95% CI, -5.3 to 5.3] for BMI surveillance). Cardiorespiratory fitness in young adulthood and a PRS are modestly associated with midlife BMI, although future BMI is associated with BMI in young adulthood. Fitness has a comparable association with future BMI as does the PRS. Caution should be exercised in the widespread use of polygenic risk for obesity prevention in adults, and close clinical surveillance and fitness may have prime roles in limiting the adverse consequences of elevated BMI on health.

Physical exercise and body-mass index in young adults: a national survey of Norwegian university students

BackgroundPhysical inactivity and obesity pose a major public health challenge. The aim of this study was to describe the level of physical exercise and body-mass index in college and university students, as well as to examine potential changes from 2010 to 2018.MethodsData stem from the SHoT study, a national student health survey for higher education in Norway, conducted at 4-year intervals. The SHOT studies conducted so far in 2010, 2014 and 2018, included 6053, 13,525 and 50,054 fulltime students (aged 18–35), respectively. Exercise frequency (average number of times exercising each week) was assessed in all three waves, and was used for the trend analysis. The last wave in 2018 also assessed the average intensity and duration of the exercise.ResultsOverall, students exercised less in 2018 compared to 2014, but comparable to level in 2010. The prevalence of overweight increased substantially from 2010 to 2018, but especially in the last 4 years and among older female students. Less than one of four male, and one of five female students, met the recommended criteria for both exercise frequency, intensity and duration. As expected, the associations between exercise and overweight/obesity were in a dose-response manner, and strong across all three waves.ConclusionsOur findings show that the large majority of young adults fail to meet international recommendations on exercise, and that the proportion of overweight is increasing in both genders and across all age groups. We conclude that there is an urgent need for a broad approach to achieve a paradigm shift in supporting our college and university students to become more active.

Levels of Physical Activity, Obesity and Related Factors in Young Adults Aged 18-30 during 2009-2017.

The objective of this study was to analyze the temporal trend of physical activity and body mass index in young adults aged 18–30 in Spain and to ascertain their relationship with sociodemographic and psychosocial variables in the period of 2009–2017. Methods: A descriptive study with a sample of 10,061 young adults aged 18–30 years was performed. The data were obtained from the European Health Survey in Spain in 2009 and 2014 and the National Health Survey in 2011/2012 and 2017. The chi-square test was used for qualitative variables, and multiple linear regression analysis was performed for physical activity. Results: Sedentary levels had decreased in 2017 as compared to 2011/2012 (p < 0.001); smokers were more sedentary than non-smokers (p < 0.001); men were more active than women (p < 0.001); and the year with the highest physical activity was 2014. Body mass index in the total sample increased from 2009 to 2017 (p < 0.01), showing a significant increase in obesity in women (p < 0.05) and no difference in men (p ≥ 0.05). Conclusions: In the period 2011/2012–2017, the sedentary lifestyle of young adults was reduced and physical activity was increased, with men being more active than women.

Predicting overweight and obesity in young adulthood from childhood body-mass index: comparison of cutoffs derived from longitudinal and cross-sectional data

Historically, cutoff points for childhood and adolescent overweight and obesity have been based on population-specific percentiles derived from cross-sectional data. To obtain cutoff points that might better predict overweight and obesity in young adulthood, we examined the association between childhood body-mass index (BMI) and young adulthood BMI status in a longitudinal cohort. In this study, we used data from the International Childhood Cardiovascular Cohort (i3C) Consortium (which included seven childhood cohorts from the USA, Australia, and Finland) to establish childhood overweight and obesity cutoff points that best predict BMI status at the age of 18 years. We included 3779 children who were followed up from 1970 onwards, and had at least one childhood BMI measurement between ages 6 years and 17 years and a BMI measurement specifically at age 18 years. We used logistic regression to assess the association between BMI in childhood and young adulthood obesity. We used the area under the receiver operating characteristic curve (AUROC) to assess the ability of fitted models to discriminate between different BMI status groups in young adulthood. The cutoff points were then compared with those defined by the International Obesity Task Force (IOTF), which used cross-sectional data, and tested for sensitivity and specificity in a separate, independent, longitudinal sample (from the Special Turku Coronary Risk Factor Intervention Project [STRIP] study) with BMI measurements available from both childhood and adulthood. The cutoff points derived from the longitudinal i3C Consortium data were lower than the IOTF cutoff points. Consequently, a larger proportion of participants in the STRIP study was classified as overweight or obese when using the i3C cutoff points than when using the IOTF cutoff points. Especially for obesity, i3C cutoff points were significantly better at identifying those who would become obese later in life. In the independent sample, the AUROC values for overweight ranged from 0·75 (95% CI 0·70-0·80) to 0·88 (0·84-0·93) for the i3C cutoff points, and the corresponding values for the IOTF cutoff points ranged from 0·69 (0·62-0·75) to 0·87 (0·82-0·92). For obesity, the AUROC values ranged from 0·84 (0·75-0·93) to 0·90 (0·82-0·98) for the i3C cutoff points and 0·57 (0·49-0·66) to 0·76 (0·65-0·88) for IOTF cutoff points. The childhood BMI cutoff points obtained from the i3C Consortium longitudinal data can better predict risk of overweight and obesity in young adulthood than can standards that are currently used based on cross-sectional data. Such cutoff points should help to more accurately identify children at risk of adult overweight or obesity. None.

The relationship between culture, food liking, and body mass index in Australian and Thai young adults.

An individual's liking of food may be associated with Body Mass Index (BMI) due to its subsequent impact on food consumption. This study investigates the association between food liking and BMI in young adults from Australia and Thailand. Food liking data were collected via a validated online Food Liking Questionnaire (FLQ). Food liking scores were calculated for overall liking of groupings of foods: grains, vegetables, fruits, dairy, animal protein, plant-based protein, fat and oil, sweet food, salty food, and alcohol. The relationship between food liking and BMI (calculated from self-reported height and weight) was assessed using linear regression models including country and gender, and mean differences were assessed using independent sample t-test. Data were available from n=4,173 participants (BMI=22.25 (SD 4.18), age=20.6 (SD 4.22) years, female=71.6%, Thai=52.5%). There were significant differences of food liking between countries for all of food groups (p<0.01) except for animal-based protein and plantbased protein liking. BMI was positively, but weakly, associated with liking of animal-based protein (β=0.20 [0.12, 0.28], p<0.001), and alcohol (β=0.08 [0.02, 0.13], p<0.01) and negatively associated with plant-based protein (β=-0.09 [-0.18, -0.01], p<0.05). There was significant difference of food liking between weight status for all of food groups. This study supports only minor associations between food liking and BMI, but cultural and gender variation in liking was evident.

Genetic risk, body mass index, and weight control behaviors: Unlocking the triad.

The relationship between genetic risk for body mass index (BMI) and weight control behaviors remains unknown. The objectives of this study were to determine the association between genetic risk for BMI and weight control behaviors in young adults, and to examine actual measured BMI as a potential mediator variable. We analyzed data from three data collection waves of the National Longitudinal Study of Adolescent to Adult Health. The BMI polygenic score (PGS) was based on published genome-wide association studies for BMI. BMI was collected at 11-18 years and 18-26 years. Weight control behaviors included self-reported: (a) weight loss behaviors (dieting, vomiting, fasting/skipping meals, diet pills, laxatives, or diuretic use to lose weight) and (b) weight gain behaviors (eating more or different foods than normal, taking supplements to gain weight). Among 4,397 participants, the BMI PGS was associated with higher odds of weight loss behaviors in females (OR 1.24, 95% CI 1.14-1.35) and males (OR 1.43, 95% CI 1.26-1.62), and this association was mediated by BMI (indirect effect 0.04, 95% CI 0.03-0.05 in females and 0.03, 95% CI 0.03-0.04 in males). The BMI PGS was associated with lower odds of weight gain behaviors in females and males, which was also mediated by actual BMI. The BMI PGS was associated with weight loss behaviors in both males and females, and this association was mediated by actual measured BMI. Clinical interventions to prevent high BMI, particularly for individuals with genetic risk, may also prevent subsequent development of potentially unhealthy weight loss behaviors.

Context Matters: Adolescent Neighborhood and School Influences on Young Adult Body Mass Index

PurposeBoth schools and neighborhoods play important roles in determining adolescent weight status, but little is known about their relative importance, particularly in predicting long-term weight outcomes. We assessed the impacts of both school and neighborhood socioeconomic composition, social connectedness, and built environment during adolescence on weight status in young adulthood. MethodsThe study sample consisted of 14,625 respondents from Waves I and IV of the National Longitudinal Study of Adolescent to Adult Health. Data were analyzed using cross-classified multilevel modeling to examine the joint effect of adolescents’ school and neighborhood predictors on body mass index (BMI) 13 years later. ResultsLiving in a neighborhood with lower average parent education during adolescence, and attending a school with lower average parent education, were each associated with higher BMI in young adulthood. Living in a neighborhood with more physical activity resources predicted lower young adult BMI, independent of adolescent weight, parent obesity status, and demographic characteristics. School physical activity resources and perceptions of social connectedness (in the school or neighborhood) were not significantly associated with young adult BMI. ConclusionsThese findings highlight the importance of school and neighborhood socioeconomic composition during adolescence on young adult weight status. Results also suggest that improving neighborhood infrastructure may promote healthy weight.

Anthropometric Traits and Risk of Non-Hodgkin Lymphoma (NHL) and Major NHL Subtypes: A Pooled Prospective Analysis

Background: Collectively, non-Hodgkin lymphomas (NHL) are expected to account for >95,000 new cancer diagnoses and >24,000 cancer deaths in the United States in 2018. Few NHL risk factors are known other than severe immune compromise, family history of lymphoid malignancies, and some pathogens. Evidence for modifiable risk factors that could inform prevention strategies is limited, especially from prospective studies. An association of anthropometric traits with NHL risk is biologically plausible given the emerging knowledge that obese individuals have heightened inflammation and deregulation of endogenous hormonal pathways that can influence cell cycle control and lymphocyte activation. We undertook the present prospective study to elucidate the associations of young (aged 18-21 years) and usual adult body mass index (BMI), height, weight, and waist circumference with risk of NHL and major histologic subtypes of NHL. The completed analysis will leverage the resources of several large population samples across the United States with prospectively assessed repeated measures of anthropometric traits and high rates of follow-up for disease ascertainment.Methods: We pooled data from large prospective cohort studies with repeated measures of anthropometric traits and follow-up over 23 - 38 years for cancer endpoints, including the Cancer Prevention Study-II (CPS-II) Nutrition Cohort, Health Professionals Follow-up Study (HPFS), Nurses' Health Study (NHS), and NHS II. Incident NHL diagnoses were confirmed by review of medical records or cancer registries, and classified for histologic subtype according to the WHO classification scheme and corresponding InterLymph-recommended analytic groups: chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), and T-cell NHL (T-NHL). Weight was ascertained approximately every two years throughout follow-up, all other anthropometric measures were ascertained on a single survey, usually at baseline. We considered cumulative average of BMI (hereafter “usual adult BMI”) by averaging across all completed cohort-specific questionnaires. Current weight was analyzed as time-varying. In cohort- and sex-specific analyses, there was no evidence of statistically significant heterogeneity; thus we pooled directly across cohorts to maximize our sample size for statistical modeling. Cox proportional hazard regression models adjusted for age, cohort, and sex were used to estimate hazard ratios (HR) and 95% confidence intervals (CIs) for each trait's association with NHL or NHL subtype risk.Results: The pooled sample comprised 5,005 confirmed incident cases of NHL, including 1117 CLL/SLL, 918 DLBCL, 709 FL and 277 T-NHLs ascertained over 9.4 million person-years of follow-up. There was a significant, positive association of usual adult BMI with NHL overall (HR: 1.05, 95% CI: 1.01-1.08 per 5 kg/m2; Table 1), which was driven by DLBCL (HR: 1.21, 95% CI: 1.12-1.30 per 5 kg/m2). No association was apparent for FL, CLL/SLL or T-NHL. Similarly, waist circumference was associated with NHL risk overall (HR: 1.04, 95% CI: 1.00-1.09 per 15cm), but driven by the association for DLBCL (HR: 1.16, 95% CI: 1.05-1.27 per 15cm). In contrast, a statistically significant or suggestive association for BMI in young adulthood was observed for all NHL endpoints, but again, most strongly with DLBCL (HR: 1.28, 95% CI: 1.15-1.43 per 5 kg/m2). Height was positively associated with all NHL endpoints except T-NHL. Associations for current and young adult weight were similar to those for the corresponding BMI variables.Conclusions: Preliminary results from this prospective analysis suggest that, unlike BMI later in life, young adult BMI is consistently associated with all major subtypes of NHL. In contrast, usual adult BMI and waist circumference are uniquely associated with DLBCL. In general, the strongest associations with anthropometric factors were observed for DLBCL. Further analyses of these data are ongoing, including efforts to incorporate data from two additional large cohorts. These findings further demonstrate the etiologic heterogeneity of NHL subtypes and underscore the importance of maintaining a healthy body weight throughout life, including at younger ages. [Display omitted] DisclosuresChao:Seattle Genetics: Research Funding.

Adiposity throughout the life course and risk of venous thromboembolism

ObjectiveAdult body mass index (BMI) is strongly associated with venous thromboembolism (VTE), however whether earlier-life adiposity or other measures of adult adiposity are associated with VTE risk remains largely unknown. Materials and methodsWe evaluated associations of childhood somatotype, BMI in early adulthood, adult adiposity, and change in weight since early adulthood with incident VTE risk over ≥20 years of follow-up among 205,935 participants from Nurses' Health Studies (NHS/NHS II) and Health Professionals Follow-Up Study (HPFS), ages 29–76 at baseline. We estimated multivariable-adjusted hazard ratios for VTE using Cox proportional hazards models. Results and conclusionsSomatotype in childhood and young adulthood BMI were not significantly associated with VTE risk, after accounting for adult BMI. Adult BMI was strongly associated with VTE in all three cohorts (e.g., multivariable-adjusted HRs comparing ≥35 kg/m2 vs. <22.5 kg/m2: NHS:3.03[95% CI: 2.58, 3.56], NHS II:3.82[95% CI: 3.24, 4.51], HPFS:2.81 [95% CI: 2.08, 3.80]; all p-trends < 0.01). Adult waist circumference was associated with greater VTE risk, even after adjusting for adult BMI (all p-trends < 0.01). Increasing weight gain from young adulthood was significantly associated with VTE after adjusting for current BMI among women (HR comparing gain ≥20 kg vs. no change: NHS:1.36[95% CI: 1.13, 1.65], NHS II:1.48[95% CI: 1.17, 1.87]) and not men (HPFS:1.20[95% CI: 0.97, 1.50]). These results indicate that BMI and adiposity are likely more important acutely than cumulatively over time in the etiology and prevention of VTE. Clinically, encouraging weight loss in individuals who are overweight or obese could help reduce VTE risk.

Self-Reported vs. Measured Height, Weight, and BMI in Young Adults.

Self-reported height and weight, if accurate, provide a simple and economical method to track changes in body weight over time. Literature suggests adults tend to under-report their own weight and that the gap between self-reported weight and actual weight increases with obesity. This study investigates the extent of discrepancy in self-reported height, weight, and subsequent Body Mass Index (BMI) versus actual measurements in young adults. Physically measured and self-reported height and weight were taken from 1562 students. Male students marginally overestimated height, while females were closer to target. Males, on average, closely self-reported weight. Self-reported anthropometrics remained statistically correlated to actual measures in both sexes. Categorical variables of calculated BMI from both self-reported and actual height and weight resulted in significant agreement for both sexes. Researcher measured BMI (via anthropometric height and weight) and sex were both found to have association with self-reported weight while only sex was related to height difference. Regression examining weight difference and BMI was significant, specifically with a negative slope indicating increased BMI led to increased underestimation of weight in both sexes. This study suggests self-reported anthropometric measurements in young adults can be used to calculate BMI for weight classification purposes. Further investigation is needed to better assess self-reported vs measured height and weight discrepancies across populations.

Adjustment for Waist Circumference Reveals a U-Shaped Association Between Glycated Hemoglobin Levels and Body Mass Index in Young Adults.

Body mass index (BMI) is used to assess adiposity worldwide. However, additional adjustment for waist circumference (WC), a surrogate marker of abdominal fat, may be capable of revealing a latent relationship between low body weight and glycated hemoglobin (A1C) concentration. Here, we investigated the relationship between A1C and BMI in young adults, adjusting for WC. We reviewed A1C, BMI, WC and other clinical data in a cross-sectional study of 26,475 apparently healthy Japanese people 20 to 39 years of age who were undergoing health check-ups. Although the values of most serum parameters were high in subjects with a high BMI in both younger (20 to 29 years of age, n=10,810) and older subjects (30 to 39 years of age, n=15,665), A1C had a J-shaped relationship with BMI category in younger subjects, regardless of sex. A traditional linear model via a generalized linear model showed that in younger subjects, an inverse association of A1C level with BMI category (19 to 26.9 kg/m2 vs. ≤18.9 kg/m2) was identified after adjustment for WC. This indicates positive associations between A1C and BMI categories of ≤18.9 (beta=0.06; p<0.0001), 19.0 to 20.9 (beta=0.03; p<0.01) and ≥27.0 kg/m2 (beta=0.08; p<0.0001), in contrast to individuals with BMIs of 23.0 to 24.9 kg/m2. Similarly, in older subjects, BMIs ≤18.9 kg/m2 were associated with A1C levels but to a lesser extent (beta=0.04; p<0.05) than in younger subjects. Additional adjustment of BMI for WC revealed a latent U-shaped association between A1C concentration and BMI, particularly in young adults; this deserves further investigation.

Height, waist circumference, body mass index, and body somatotype across the life course and risk of glioma.

Recent studies have suggested height as a risk factor for glioma, but less is known regarding body mass index (BMI) or other anthropomorphic measures. We evaluated the association between body habitus and risk of glioma. We evaluated the association of measures of height, BMI, waist circumference, and somatotypes with risk of glioma in two prospective cohorts, the Nurses' Health Study and the Health Professionals Follow-Up Study. We documented 508 incident cases of glioma (321 glioblastoma [GBM]). In both cohorts, we found no significant association between adult BMI or waist circumference and risk of glioma, with pooled HR for BMI of 1.08 (95% CI 0.85-1.38 comparing ≥ 30 to < 25kg/m2) and for waist circumference of 1.05 (95% CI 0.80-1.37 highest vs. lowest quintile). Higher young adult BMI (at age 18 in NHS and 21 in HPFS) was associated with modestly increased risk of glioma in the pooled cohorts (pooled HR 1.35, 95% CI 1.06-1.72 comparing ≥ 25kg/m2 vs. less; HR 1.34 for women and 1.37 for men). Analysis of body somatotypes suggested reduced risk of glioma among women with heavier body types at all ages this measure was assessed (HRs ranging from 0.52 to 0.65 comparing highest tertile to lowest tertile), but no significant association among men. Height was associated with increased risk of glioma among women (HR 1.09, 95% CI 1.04-1.14 per inch), but not significantly among men. Within the 8 years prior to diagnosis, cases had no material weight loss compared to non-cases. All results were similar when limited to GBM. Adult BMI and waist circumference were not associated with glioma. Higher BMI at age 21 for men and at age 18 for women was modestly associated with risk in the pooled cohort. Based on body somatotypes, however, women with heavier body types during childhood and young adulthood may be at lower risk of glioma, although this association was not observed later in life with measurements of BMI. Greater height was associated with increased risk, and the trend was more pronounced in women.

Does the cortisol awakening response link childhood adversity to adult BMI?

Childhood adversity is a risk factor for the development of obesity in adulthood. Dysregulated hypothalamic-pituitary-adrenal (HPA) activity, which has been associated separately with both adverse childhood experiences and obesity, has been posited as a mechanism by which stressful experiences influence body mass index (BMI); however, this mechanism has not yet been tested longitudinally. The present study uses multireporter, longitudinal data across three time points to test whether the adolescent cortisol awakening response (CAR), an index of diurnal HPA activity, mediates the association between adversity in childhood and BMI in adulthood. Eighty-two youth, mothers, and fathers reported on adverse childhood experiences from middle childhood to late adolescence. During adolescence, youth provided saliva samples three times each morning across three days, which were assayed for cortisol to calculate CAR. During early adulthood, youth reported height and weight to calculate BMI. Greater adversity predicted flatter CAR and higher young adult BMI. Flatter CAR partially mediated the association between childhood adversity and young adult BMI. Stress-related alterations to HPA activity account in part for the childhood adversity-adult obesity link. Findings are consistent with theoretical models implicating HPA alterations as linking childhood adversity to metabolic and behavioral determinants of BMI in adulthood. (PsycINFO Database Record

Coronal Knee Malalignment in Young Adults and Its Link to Body Measures.

Our aim was to report the prevalence of knee varus-valgus malalignment (KVVM) and its association with body mass index (BMI) and body height in a healthy and fit young adult population. Information on the disability codes associated with KVVM according to the Regulations of Medical Fitness Determination was retrieved from a medical database containing records of 17-year-old males and females before their recruitment into mandatory military service. Logistic regression models assessed the association between the BMI and body height to KVVM. The study cohort included 821,381 subjects (460,674 males and 360,707 females). The prevalence of KVVM was 0.9% in males and 0.6% for females. Under/overweight subjects were associated with higher prevalence of KVVM. The odds ratios (ORs) had a "J" curve pattern, increasing for underweight males and females, and even more so for above-normal BMIs (for obese males and for both overweight and obese females). The strongest association was between obese females and KVVM: an obese female had an OR of 22.864 (confidence interval [CI] = 20.683-25.725, p < 0.001) to have KVVM and an obese male had an OR of 4.483 (CI = 4.158-4.833 p < 0.001). When the BMI was analyzed as a continuous variable, each increase in one BMI unit was associated with an increase in OR of 7.6% for males and 24.1% for females. There is a strong association between BMI and KVVM in both underweight and overweight young adults. KVVM is more common in males, but most strongly associated with overweight and obese females.This is a Level III, case-control study.

Body Mass, Total Body Fat Percentage, and Visceral Fat Level Predict Insulin Resistance Better Than Waist Circumference and Body Mass Index in Healthy Young Male Adults in Indonesia.

The incidence of obesity which leads to insulin resistance (IR) and metabolic disorder is increasing in developing countries, including Indonesia. Male adults have a higher risk of abdominal obesity than females. This is associated with cardiometabolic disorders. Several anthropometric measurements have been proposed to predict IR. The aim of this study was to investigate whether body mass, body mass index (BMI), waist circumference (WC), body fat percentage (BF) or visceral fat level (VF) could become a better predictor of IR in healthy young male adults. A total of 140 healthy young male adults ranging from 18–25 years were recruited in the study. Insulin resistance was measured by calculating their Homeostatic Model Assessment for Insulin Resistance (HOMA-IR). Subjects with a HOMA-IR value ≥75th percentile, with cut off 3.75, were defined as IR. Anthropometric measurements including body weight, BMI, and WC were performed, whereas BF and VC were measured using bioelectrical impedance analysis (BIA). IR had a strong correlation with body weight, BMI, WC, BF, and VF. In the area under the curve of body mass, BF and VF were slightly greater than WC and BMI. Anthropometric measurements correlated strongly with IR but body weight, BF, VF had a stronger correlation than WC and BMI in healthy young male adults.