Being overweight in early adulthood is associated with increased mortality in middle age

Prevalence of metabolically healthy obesity and healthy overweight and the associated factors in southern Iran: A population-based cross-sectional study

Background and Aims

Obesity is considered a major growing threat to public health which could negatively affect the quality of life. The current cross-sectional study was conducted to investigate the population-based prevalence of metabolically healthy obesity (MHO) and healthy overweight (MHOW) and associated factors in southern Iran.

Methods

Baseline data from the Pars Cohort Study was analyzed. Metabolically healthy participants were identified based on the definition of the American Heart Association for the metabolic syndrome. The prevalence of MHOW and MHO and their 95% confidence intervals were estimated. Poisson regression was applied for the calculation of prevalence ratios (PRs).

Results

Gender- and age-standardized prevalences of MHOW and MHO were 6.3% (6.0%-6.6%) and 2.3% (2.1%-2.5%), respectively. The following factors were associated with being MHOW compared with those with normal weight: Being younger, female gender (1.31, 1.20-1.43), higher socioeconomic status, being noncurrent cigarette smoker (1.27, 1.11-1.45), low level of physical activity (1.14, 1.03-1.25), having normal overweight during adolescence, and overweight (1.35, 1.24-1.48) or obesity (1.68, 1.53-1.86) during young adulthood. We also found strong associations between MHO and younger age groups, female gender (2.87, 2.40-3.42), being married (1.57, 1.08-2.27), Fars ethnicity (1.25, 1.10-1.43), higher socioeconomic status, ever use of tobacco (1.14, 1.00-1.30), never use of opium (1.85, 1.19-2.86), lower physical activity (1.45, 1.20-1.72), being normal weight in 15-year body pictogram and being overweight (1.87, 1.59-2.20) or obese (3.20, 2.74-3.72) in 30-year body pictogram when considering those with normal weight or MHO.

Conclusion

Potentially modifiable factors including physical activity should be more emphasized. Furthermore, our study issued that it would be more reasonable that the prevention of unhealthy obesity be initiated before the development of MHO, where there are more protective factors and they could be more effective.

Obesity at age 20 and weight gain during adulthood increase risk of total and premature all-cause mortality: findings from women attending breast screening in Manchester

BACKGROUND

Obesity in early adulthood is associated with lower breast cancer rates in later life. This could be interpreted as a positive reinforcement of excess weight amongst younger women however, the wider implications of higher weights are less well known. This study examined the association between both obesity in early adulthood and body mass index (BMI) change through adulthood, and all-cause mortality.

METHODS

The Predicting Risk of Cancer At Screening (PROCAS) study recruited 57,902 women aged 46-73 years (median age 57.2, IQR 51.8-63.7 years) from the Greater Manchester National Health Service breast screening programme in North West England between 2009 and 2015. It was used to assess associations between BMI at 20 years and cohort entry with all-cause mortality ascertained via deaths recorded on the National Breast Screening System to June 2020. Hazard ratios were estimated using proportional hazards (Cox) regression adjusted for factors at entry to the cohort: age, deprivation, bilateral oophorectomy, hormone-replacement therapy, menopausal status, ethnicity, alcohol intake, physical activity, and BMI.

RESULTS

The prevalence of overweight (25-30 kg/m²) and obesity (> 30 kg/m²) were 10.4% and 2.5% respectively at 20 years, increasing to 35.2% and 25.9% respectively at cohort entry. After a mean 8.7 years follow-up we observed that overweight (HR = 1.27, 95%CI = 1.10-1.47) and obesity (HR = 2.11, 95%CI = 1.67-2.66) at 20 years had a higher mortality rate compared with healthy weight. Women who were underweight/healthy weight at 20 years and gained weight to obesity at entry had a slightly increased mortality rate compared with women who were underweight/healthy weight at both time points (HR 1.16, 95%CI = 1.02-1.32). Women with overweight (HR = 1.36, 95%CI = 1.06-1.75) or obesity (HR = 1.90, 95%CI = 1.45-2.48) at both 20 years and entry had a higher mortality rate than women who were underweight/healthy weight at both points.

CONCLUSIONS

Women who self-reported overweight and obesity at 20 years had a shorter life expectancy in this cohort of women attending breast cancer screening. Weight gain from 20 years was common in this group. Girls and women should be supported to maintain a healthy weight throughout the lifespan to help increase life expectancy. Trial registration number NCT04359420, retrospectively registered 24/04/2020.

Time trends of overweight and obesity among schoolchildren in Kuwait over a 13-year period (2007-2019): repeated cross-sectional study

OBJECTIVES

This study aimed to examine age-specific trends in the prevalence of overweight and obesity in schoolchildren in Kuwait over a 13-year period (2007 to 2019) using the WHO, the Centers for Disease Control and Prevention (CDC) and the International Obesity Taskforce (IOTF) definitions.

DESIGN

Using cross-sectional approach, Kuwait Nutrition Surveillance System (KNSS) objectively measured weight and height of schoolchildren over a 13-year period. Log-binomial regression models were used to examine age-specific trends of obesity and overweight over the study period.

SETTING

Public primary, middle and high schools in all provinces of Kuwait.

PARTICIPANTS

Schoolchildren aged 5-19 years (n 172 603).

RESULTS

According to the WHO definition, the prevalence of overweight and obesity in schoolchildren, respectively, increased from 17·73 % and 21·37 % in 2007 to 20·19 % and 28·39 % in 2019 (Pfor trend < 0·001). There is evidence that the obesity in females (but not males) has levelled off in the period 2014-2019 according to the three definitions of obesity, which is corroborated by a similar trend in the mean of BMI-for-age Z-score.

CONCLUSION

The prevalence of obesity and overweight in schoolchildren in Kuwait has risen over the last 13 years and trends are similar across all definitions. Obesity is no longer increasing at the same pace and there is evidence that the prevalence of obesity in females has plateaued. The current level of childhood overweight and obesity is too high and requires community-based and school-based interventions.

Association between "a body shape index" and mortality: Bambuí Cohort Study of Aging, Brazil

This article aims to evaluate the joint and separate association between abdominal and general adiposity indicators and mortality. Data was collected from 1,366 older adults in the Bambuí Cohort Study of Aging with complete information for all variables of interest. The outcome variable was all-cause time until death; exposure variables were a body shape index (ABSI), waist circumference (WC), waist-to-height ratio (WHtR) and body mass index (BMI), assessed at the beginning of the study, and at the 3rd, 5th and 11th year of follow-up. Association between the quartiles of anthropometric indicators and mortality was calculated using an extended Cox proportional hazards model and adjusted for socioeconomic and behavioral confounding factors. Older adults in the 4th ABSI quartile had a higher risk of mortality regardless of BMI (1.27; 95%CI: 1.01-1.58), but this association was not observed in sensitivity analyses. Older adults in the 2nd, 3rd and 4th BMI quartiles had a lower risk of mortality, even when adjusted for WC or ABSI. WC and WHtR showed no association consistent with all-cause mortality after adjustment for confounding factors. Considering the loss of significance in the sensitivity analyses, ABSI's predictive capacity for mortality is still weak. Thus, adopting ABSI in clinical practice or in epidemiological surveys, in conjunction or replacing BMI and WC, requires more in-depth studies.

Body shape trajectories and mortality in the Seguimiento universidad de Navarra (SUN) cohort

BACKGROUND AND AIM

The aim of this study was to assess the association between body shape trajectories and all-cause mortality in a Mediterranean cohort.

METHODS AND RESULTS

Using a group-based modeling approach to fit body shape trajectories from the age of 5-40 years, among 11,423 participants from the Spanish SUN cohort, we assessed the subsequent risk of all-cause mortality. To create the trajectories, we used a censored normal model as a polynomial function of age. Cox regression models adjusted for sex, age, years of university education, marital status, smoking status, package-years of smoking, and recruitment period were used to estimate the hazard ratios (HR) for mortality according to each assigned trajectory. Overall, five distinct trajectories were identified: "lean-moderate increase," "medium-moderate increase," "medium-stable," "heavy-medium," and "heavy-moderate increase." During 106,657 person-years of follow-up, we observed 240 deaths. Compared with those who maintained a medium body shape in early and middle life ("medium-stable" trajectory), those who were heavy and had a moderate increase ("heavy-moderate increase" trajectory) showed higher mortality risk [HR = 1.91 (95% confidence interval: 1.14-3.21)]. In contrast, participants who were heavy in early life, and then decreased their body shape during early adulthood, and maintained a medium body shape throughout middle adulthood ("heavy-medium"), tend to exhibit lower mortality risk [HR = 0.60 (0.34-1.05)], similarly to those who were lean at childhood and had a moderate increase during adulthood ("lean-moderate increase") [HR = 0.82 (0.58-1.15)].

CONCLUSION

A moderate increase in body shape among subjects who were already heavy at early life was associated with higher risk of mortality in a Mediterranean cohort of university graduates.

Body mass index and all-cause mortality in older adults: A scoping review of observational studies

In older age, body composition changes as fat mass increases and redistributes. Therefore, the current body mass index (BMI) classification may not accurately reflect risk in older adults (65+). This study aimed to review the evidence on the association between BMI and all-cause mortality in older adults and specifically, the findings regarding overweight and obese BMI. A systematic search of the OVID MEDLINE and Embase databases was conducted between 2013 and September 2018. Observational studies examining the association between BMI and all-cause mortality within a community-dwelling population aged 65+ were included. Seventy-one articles were included. Studies operationalized BMI categorically (n = 60), continuously (n = 8) or as a numerical change/group transition (n = 7). Reduced risk of mortality was observed for the overweight BMI class compared with the normal BMI class (hazard ratios [HR] ranged 0.41-0.96) and for class 1 or 2 obesity in some studies. Among studies examining BMI change, increases in BMI demonstrated lower mortality risks compared with decreases in BMI (HR: 0.83-0.95). Overweight BMI classification or a higher BMI value may be protective with regard to all-cause mortality, relative to normal BMI, in older adults. These findings demonstrate the potential need for age-specific BMI cut-points in older adults.

Associations between anthropometric indices, blood pressure and physical fitness performance in young Swiss men: a cross-sectional study

OBJECTIVES

To assess the benefit of waist circumference (WC) measurements during routine conscription medical examination in two military conscription centres in Switzerland. We compared the prevalence of overweight and obesity assessed by body mass index (BMI) with the prevalence of elevated disease risks assessed by WC and waist-to-height ratio (WHtR). We investigated how these measures were associated with systolic blood pressure, physical fitness performance and socioeconomic determinants.

DESIGN

Cross-sectional survey.

SETTING

Two Swiss conscription centres in 2016.

PARTICIPANTS

1548 Swiss male conscripts, 18-22 years old.

MAIN OUTCOME

Prevalences of elevated WC, WHtR and BMI values according to WHO categories. Secondary outcomes include systolic blood pressure, physical fitness performance and endurance performance.

RESULTS

Using BMI cut-points, 25.0% of all conscripts were overweight or obese. When applying WC cut-points, 9.2% had an increased disease risk, while 14.8% of the conscripts were at risk using WHtR cut-points. In the BMI range of 25.0-27.4 kg/m², 3.6% showed an increased disease risk when using WC and 24.6% when using WHtR cut-points. Of the conscripts with a BMI of 27.5-29.9 kg/m², 72.4% had an increased disease risk using WHtR, and 42.5% when using WC cut-points. Determinants of elevated BMI, WC and WHtR were low occupational status, rural residential area, older age and location in central and Northwest Switzerland. Systolic blood pressure increased with increasing BMI, WC and WHtR. Physical fitness and endurance test performances decreased with increasing BMI, WC and WHtR.

CONCLUSION

In addition to BMI, WC and WHtR add relevant information to the health assessment of young men. However, the prevalence of overweight/increased health risk differed when using BMI, WC or WHtR. Further studies should include measures of body composition to test whether these differences arise from muscular young men within the overweight BMI range, who had a normal WC.

A Targeted and Tailored eHealth Weight Loss Program for Young Women: The Be Positive Be Healthe Randomized Controlled Trial

Young women are gaining weight rapidly. Evidence for effective weight loss interventions targeting young women is lacking. This randomized controlled trial assessed the efficacy and acceptability of a six-month targeted and tailored eHealth weight loss program for young women (Be Positive Be Healthe (BPBH)). Women aged 18–35 years were randomized to BPBH (n = 29) or control (n = 28). BPBH supported participants to modify diet and physical activity behaviours using evidenced-based strategies (e.g., self-monitoring) tailored for young women and delivered using e-health (website, social media, smartphone application, email, text messages). The primary outcome was a change in weight (kg) at six months. Acceptability was assessed via a process evaluation survey and usage of intervention components. No significant between-group differences were observed for weight, with significant mean differences favouring the intervention group observed for body fat (kg) (−3.10 (−5.69, 0.52), p = 0.019) and intakes of alcohol (g) (−0.69 (−1.33, 0.04), p = 0.037), vegetables (% energy/day) (4.71 (−2.20, 7.22), p < 0.001) and energy-dense, nutrient-poor foods (% energy/day) (−9.23 (−16.94, 1.52), p = 0.018). Retention, intervention usage and satisfaction were moderate. BPBH facilitated positive improvements in body fat and dietary intake, but not weight. Intervention acceptability findings support the use of some intervention components (e.g., Facebook, Smartphone app) with young women.

Prevalence and Trends in Lifetime Obesity in the U.S., 1988-2014

INTRODUCTION

Estimates of obesity prevalence based on current BMI are an important but incomplete indicator of the total effects of obesity on a population.

METHODS

In this study, data on current BMI and maximum BMI were used to estimate prevalence and trends in lifetime obesity status, defined using the categories never (maximum BMI ≤30 kg/m²), former (maximum BMI ≥30 kg/m² and current BMI ≤30 kg/m²), and current obesity (current BMI ≥30 kg/m²). Prevalence was estimated for the period 2013-2014 and trends for the period 1988-2014 using data from the National Health and Nutrition Examination Survey. Predictors of lifetime weight status and the association between lifetime weight categories and prevalent disease status were also investigated using multivariable regression.

RESULTS

A total of 50.8% of American males and 51.6% of American females were ever obese in 2013-2014. The prevalence of lifetime obesity exceeded the prevalence of current obesity by amounts that were greater for males and for older persons. The gap between the two prevalence values has risen over time. By 2013-2014, a total of 22.0% of individuals who were not currently obese had formerly been obese. For each of eight diseases considered, prevalence was higher among the formerly obese than among the never obese.

CONCLUSIONS

A larger fraction of the population is affected by obesity and its health consequences than is suggested in prior studies based on current BMI alone. Weight history should be incorporated into routine health surveillance of the obesity epidemic for a full accounting of the effects of obesity on the U.S.

Improving risk estimates for metabolically healthy obesity and mortality using a refined healthy reference group

OBJECTIVE

We aimed to re-examine mortality risk estimates for metabolically healthy obesity by using a 'stable' healthy non-obese referent group.

DESIGN

Prospective cohort study.

METHODS

Participants were 5427 men and women (aged 65.9 ± 9.4 years, 45.9% men) from the English Longitudinal Study of Ageing. Obesity was defined as body mass index ≥30 kg/m2 (vs non-obese as below this threshold). Based on blood pressure, HDL cholesterol, triglycerides, glycated hemoglobin and C-reactive protein, participants were classified as 'healthy' (0 or 1 metabolic abnormality) or 'unhealthy' (≥2 metabolic abnormalities).

RESULTS

Totally, 671 deaths were observed over an average follow-up of 8 years. When defining the referent group based on 1 clinical assessment, the unhealthy non-obese (hazard ratio (HR) = 1.22; 95% CI: 1.01, 1.45) and unhealthy obese (HR = 1.29; CI: 1.05, 1.60) were at greater risk of all-cause mortality compared to the healthy non-obese, yet no excess risk was seen in the healthy obese (HR = 1.14; CI: 0.83, 1.52). When we re-defined the referent group based on 2 clinical assessments, effect estimates were accentuated and healthy obesity was at increased risk of mortality (HR = 2.67; CI: 1.64, 4.34).

CONCLUSION

An unstable healthy referent group may make 'healthy obesity' appear less harmful by obscuring the benefits of remaining never obese without metabolic dysfunction.