Low length/weight growth trajectories of early-term infants during the first year: evidence from a longitudinal study in China

ObjectiveTo identify common length, weight and body mass index (BMI) growth trajectories of term infants during infancy, and to determine their association with early-term infants.DesignProspective longitudinal study.SettingWuhan, China.PatientsA total of 4308 term infants (born at 37–41 weeks of gestation) were included. All term infants were single live birth with no defects and birth weight ≥2500 g, and their mothers were permanent residents of Wuhan for more than 2 years. After excluding 887 infants, a total of 3421 term infants (1028 early-term infants born at 37–38 weeks of gestation and 2393 full-term infants born at 39–41 weeks of gestation) entered the statistical analysis stage.Main outcome measuresPatterns of length, weight and BMI growth trajectories by using group-based trajectory modelling.ResultsThree distinct physical growth trajectories were identified as follows: length: low stable (1056, 30.9%), moderate stable (1887, 55.2%) and high increasing (477, 13.9%); weight: low stable (1031, 30.1%), moderate stable (1884, 55.1%) and high increasing (505, 14.8%); BMI: low stable (689, 20.1%), moderate stable (2167, 63.4%) and high increasing (564, 16.5%). Compared with the full-term infants, early-term infants were more likely to remain at low-stable trajectory in length (OR: 1.40; 95% CI: 1.19 to 1.66) and weight (OR:1.29; 95% CI: 1.09 to 1.53). These associations were still statistically significant after adjusting potential confounders and were more evident among girls in the stratified analysis. There was no statistical association between BMI trajectory patterns and gestational age categories.ConclusionOur results suggested the heterogeneity of term infants existed in length, weight and BMI growth trajectories of early childhood. Compared with full-term birth, early-term birth was related to low length and weight trajectories rather than BMI trajectory. Further research is needed to evaluate the duration of these low trajectories and their possible long-term health effects.

Body Mass Index Trajectories in Adolescence And Incident Metabolic Syndrome in Early Adulthood

Background: The incidence of metabolic syndrome (MetS) is increasing each year, and MetS is closely related to cardiovascular diseases. Body mass index (BMI) has been widely used to measure obesity, and the relationship between MetS and BMI has been widely reported. However, the relationship between the trajectory of BMI and MetS is still unclear.Methods: Six waves of the cross-sectional China Health and Nutrition Survey (CHNS) were completed in nine provinces in China from 1993 to 2009, with more than 12,000 participants. We enrolled individuals who were aged 10 to 20 years in 1993, and 554 participants were finally included in our study. A latent class growth mixed model was used to identify different BMI trajectory patterns based on the BMI value measured at each follow-up. Participants completed blood tests and a physical examination in 2009 to allow for the diagnosis of MetS. The primary aim was to explore the relationship between different BMI trajectories and the incidence of MetS through logistic regression, adjusting for baseline age, sex, BMI, waist circumference, residence, educational background, smoking status, alcohol consumption, and nutritional intake.Result: During a follow-up of 16 years, 61 (11.01%) participants developed MetS. In multivariate-adjusted models, different BMI trajectories were significantly associated with the occurrence of MetS in early adulthood. Childhood or adolescents with a low-high BMI trajectory or a high-high BMI trajectory showed a significantly higher risk of MetS in early adulthood than those with a low-low trajectory (low-high: OR=3.40, 95% CI: 1.14-10.13, P <0.05; high-high: OR=5.81, 95% CI: 1.63-20.69, P <0.05).Conclusion: Our study identified three BMI trajectories from adolescence through 16 years of follow-up and found that in addition to baseline BMI, BMI trajectories were also an independent risk factor for incident MetS in early adulthood.

Increased Risk of Chronic Kidney Disease Associated With Weight Gain in Healthy Adults: Insight From Metabolic Profiles and Body Composition

Objective: Obesity is an established risk factor for kidney damage. In this study, we explored the long-term association of changes in body mass index (BMI) over time with incident chronic kidney disease (CKD).Methods: For this analysis, 5,393 middle-aged adults without comorbidities in the Korean Genome and Epidemiology Study (KoGES) were included. Group-based trajectory modeling was used to determine the patterns of BMI change (decreasing, stable, and increasing BMI) between baseline and year 4. The primary outcome was the subsequent development of CKD from year 4. A multivariable Cox proportional hazards model was constructed to determine the risk of incident CKD according to BMI trajectories.Results: During 55,327 person-years, incident CKD occurred in 354 (6.5%) participants; 6.0, 6.1, and 7.8 per 1,000 person-years across the trajectories, respectively (P = 0.005). In the multivariable-adjusted Cox proportional hazards model, the increasing BMI trajectory was associated with a 1.4-fold [hazard ratio (HR), 1.41; 95% CI, 1.06–1.87] a higher risk of incident CKD compared with stable BMI trajectory. This association was stronger for overweight and obese individuals. The HRs for CKD development in these two groups were 1.6 (95% CI, 1.06–1.87) and 2.2 (95% CI, 1.40–3.48), respectively. While the increasing BMI group was gaining weight, there were concomitant increases in blood pressure, insulin resistance, serum concentrations of total cholesterol, triglyceride, and high-sensitivity C-reactive protein (hs-CRP), and fat mass, but high-density lipoprotein (HDL)-cholesterol level and muscle-to-fat (MF) ratio decreased.Conclusion: Weight gain is associated with an increased risk of incident CKD in healthy adults. This association is attributed to worsening metabolic profiles and increasing fat mass.

BMI trajectory in childhood is associated with asthma incidence at young adulthood mediated by DNA methylation

Purpose Body mass index (BMI) is associated with asthma but associations of BMI temporal patterns with asthma incidence are unclear. Previous studies suggest that DNA methylation (DNAm) is associated with asthma status and variation in DNAm is a consequence of BMI changes. This study assessed the direct and indirect (via DNAm) effects of BMI trajectories in childhood on asthma incidence at young adulthood. Methods Data from the Isle of Wight (IoW) birth cohort were included in the analyses. Group-based trajectory modelling was applied to infer latent BMI trajectories from ages 1 to 10 years. An R package, ttscreening, was applied to identify differentially methylated CpGs at age 10 years associated with BMI trajectories, stratified for sex. Logistic regressions were used to further exclude CpGs with DNAm at age 10 years not associated with asthma incidence at 18 years. CpGs discovered via path analyses that mediated the association of BMI trajectories with asthma incidence in the IoW cohort were further tested in an independent cohort, the Avon Longitudinal Study of Children and Parents (ALSPAC). Results Two BMI trajectories (high vs. normal) were identified. Of the 442,474 CpG sites, DNAm at 159 CpGs in males and 212 in females were potentially associated with BMI trajectories. Assessment of their association with asthma incidence identified 9 CpGs in males and 6 CpGs in females. DNAm at 4 of these 15 CpGs showed statistically significant mediation effects (p-value < 0.05). At two of the 4 CpGs (cg23632109 and cg10817500), DNAm completely mediated the association (i.e., only statistically significant indirect effects were identified). In the ALSPAC cohort, at all four CpGs, the same direction of mediating effects were observed as those found in the IoW cohort, although statistically insignificant. Conclusion The association of BMI trajectory in childhood with asthma incidence at young adulthood is possibly mediated by DNAm.

Lifetime Weight Course as a Phenotypic Marker of Severity and Therapeutic Response in Patients with Eating Disorders

The association between lifetime weight fluctuations and clinical characteristics has been widely studied in populations with eating disorders (ED). However, there is a lack of literature examining the potential role of weight course as a transdiagnostic factor in ED so far. Therefore, the aim of this study is to compare ED severity and treatment outcomes among four specific BMI profiles based on BMI-trajectories across the lifespan: (a) persistent obesity (OB-OB; (n = 74)), (b) obesity in the past but currently in a normal weight range (OB-NW; n = 156), (c) normal weight throughout the lifespan (NW-NW; n = 756), and (d) current obesity but previously at normal weight (NW-OB; n = 314). Lifetime obesity is associated with greater general psychopathology and personality traits such as low persistence and self-directedness, and high reward dependence. Additionally, greater extreme weight changes (NW-OB and OB-NW) were associated with higher psychopathology but not with greater ED severity. Higher dropout rates were found in the OB-OB group. These results shed new light on the BMI trajectory as a transdiagnostic feature playing a pivotal role in the severity and treatment outcome in patients with ED.

Abstract P116: Higher Body Mass Index Trajectories Are Associated With Lower Levels Of Physical Activity Measured By A Smartwatch

Introduction: The prevalence of obesity is rising. Most previous studies that examined the relationship between body mass index (BMI) and physical activity measured BMI at a single time-point, ignoring the time-varying nature of BMI. The relationship between BMI trajectories and habitual physical activity in community settings remains unclear. Objective: To assess the relationship between BMI trajectories and habitual physical activity measured by daily steps from a smartwatch, among participants enrolled in the electronic Framingham Heart Study (eFHS). We hypothesized that participants whose BMI trajectories increased over a 14-year period prior to the step assessment take fewer daily steps, compared to participants who maintained stable BMI trajectories during the same time period. Methods: We used a semiparametric group-based modelling method to identify BMI trajectory patterns. Participants who attended exams 1, 2, and 3 were included in building the trajectories. Daily steps were recorded from the smartwatch provided at exam 3 with “active days” defined as days with ≥ 5watch wear-hours. We excluded participants with <30 active days. The median follow-up period for step count was 357 days (IQR: 467 days). We used generalized linear models that accounted for correlation between daily steps in the same individuals to examine the longitudinal relationship between BMI trajectory groups and daily step counts, adjusting for relevant covariates. Results: We identified three trajectory groups for the 837 eFHS participants. Group 1 included 292 participants (mean age 54 years, 57% women) whose BMI was stable (slope: 0.005, p=0.75); Group 2 included 468 participants (mean age 53 years, 56% women) whose BMI increased slightly (slope: 0.123, p<9.2e-17); and Group 3 included 77 participants (mean age 50 years, 70% women) who had the largest increase of BMI (slope: 0.318, p=2.8e-22).Adjusting for age, sex, wear time and race/ethnicity, participants in group 3 (Δ1437 steps P< 0.0001) and Group 2 (Δ422 steps, P=0.04) took significantly fewer steps, compared to participants in Group 1 (Model 1). The effect sizes were slightly attenuated but remained significant after additionally adjusting for hypertension, type 2 diabetes, current smoking, and cardiovascular disease: Group 3 took 1258 fewer steps, P=0.0001; Group 2 took 406 fewer steps, P=0.04 (Model 2). We further adjusted for sleep apnea, education, and marital status in Model 3 and observed that on average Group 3 took 1120 fewer steps (P= 0.0007) and Group 2 took 382 fewer steps (P= 0.06), compared to Group 1. Conclusion: Participants whose BMI trajectory increased over time took significantly fewer steps compared to participants with more stable BMI trajectories. Our findings suggest that levels of physical activity may correlate with greater weight gain during adulthood.

BMI Trajectory in Childhood Is Associated With Asthma Incidence at Young Adulthood Mediated by DNA Methylation

Purpose: Body mass index (BMI) is associated with asthma but associations of BMI temporal patterns with asthma incidence are unclear. Previous studies suggest that DNA methylation (DNAm) is associated with asthma status and variation in DNAm is a consequence of BMI changes. This study assessed the direct and indirect (via DNAm) effects of BMI trajectories in childhood on asthma incidence at young adulthood. Methods: Data from the Isle of Wight (IoW) birth cohort were included in the analyses. Group-based trajectory modelling was applied to infer latent BMI trajectories from ages 1 to 10 years. An R package, ttscreening, was applied to identify differentially methylated CpGs at age 10 years associated with BMI trajectories, stratified for sex. Logistic regressions were used to further exclude CpGs with DNAm at age 10 years not associated with asthma incidence at 18 years. CpGs discovered via path analyses that mediated the association of BMI trajectories with asthma incidence in the IoW cohort were further tested in an independent cohort, the Avon Longitudinal Study of Children and Parents (ALSPAC).Results: Two BMI trajectories (high vs. normal) were identified. Of the 442,474 CpG sites, DNAm at 159 CpGs in males and 212 in females were potentially associated with BMI trajectories. Assessment of their association with asthma incidence identified 9 CpGs in males and 6 CpGs in females. DNAm at 4 of these 15 CpGs showed statistically significant mediation effects (p-value<0.05). At two of the 4 CpGs (cg23632109 and cg10817500), DNAm completely mediated the association (i.e., only statistically significant indirect effects were identified). In the ALSPAC cohort, at all four CpGs, the same direction of mediating effects were observed as those found in the IoW cohort, although statistically insignificant.Conclusion: The association of BMI trajectory in childhood with asthma incidence at young adulthood is possibly mediated by DNAm.

Correction: Appetite disinhibition rather than hunger explains genetic effects on adult BMI trajectory

A Correction to this paper has been published: https://doi.org/10.1038/s41366-021-00770-0