Body mass index and all-cause mortality in a 21st century U.S. population: A National Health Interview Survey analysis

Metabolic obesity phenotypes and all-cause mortality among the Chinese oldest-old population: a prospective cohort study

BACKGROUND

The obesity paradox has been reported among older adults. However, whether the favorable effect of obesity is dependent on metabolic status remains largely unknown. We aimed to explore the association of metabolic obesity phenotypes and their changes with all-cause mortality among the Chinese oldest-old population.

METHODS

This prospective cohort study included 1207 Chinese oldest old (mean age: 91.8 years). Metabolic obesity phenotypes were determined by central obesity and metabolic status, and participants were classified into metabolically healthy obesity (MHO), metabolically unhealthy obesity (MUO), metabolically healthy non-obesity (MHN), and metabolically unhealthy non-obesity (MUN). The hazard ratios (HRs) and 95% confidence intervals (95% CIs) were estimated by Cox regression models.

RESULTS

During 5.3 years of follow-up, 640 deaths were documented. Compared with non-obesity, obesity was associated with a decreased mortality risk among participants with metabolically healthy (HR, 0.75; 95% CI, 0.63-0.91) while this association was insignificant among metabolically unhealthy. Compared to MHO, MHN (HR, 1.27; 95% CI, 1.06-1.53) and MUN (HR, 1.49; 95% CI, 1.10-2.02) were significantly associated with an increased mortality risk. Compared to those with stable MHO, those transited from MHO to MUO demonstrated a higher mortality risk (HR, 1.81; 95% CI, 1.06-3.11).

CONCLUSIONS

MHO predicts better survival among the Chinese oldest-old population. These findings suggest that ensuring optimal management of metabolic health is beneficial and taking caution in weight loss based on the individual body weight for the metabolically healthy oldest-old adults.

Selected Mesoamerican Crops - Anti-Obesity Potential and Health Promotion. A Review

Mesoamerica is the center of origin of a great number of food crops that nowadays are part of a healthy diet. Pre-Columbian civilizations utilized more than 90% of these foods as ingredient or in main dishes, as well as for remedies and religious ceremonies. Since several years ago, Mesoamerican foods have been recognized by their outstanding concentration of bioactive compounds, including, phenolic compounds, pigments, essential fatty acids, amino acids, peptides, carbohydrates and vitamins, which provide a great number of health benefits. As a result of their unique composition, these ancient crops have several positive effects, such as hypoglycemic, antioxidant, anti-obesity, anti-inflammatory, anti-ageing, neuroprotective, anti-diarrheal, and anti-hypercholesterolemic capacity. Hence, this review is focused mainly in the anti-obesity and antioxidant potential of some of the most cultivated, harvested, as well as commercialized and consumed, food crops native of Mesoamerica, like, nopal and its fruit (Opuntia ficus indica spp.), chia (Salvia hispanica L.), pumpkin (Cucurbita spp.) and cacao (Theobroma cacao).

Association between diet quality and all-cause mortality in a large Dutch cohort

Food-based dietary guidelines are helpful for governments and health agencies to encourage healthy eating at the population level. In order to assess adherence to such guidelines, index scores have been developed, the version in the Netherlands being the Dutch Healthy Diet-index (2015) (DHD2015-index), which reflect adherence to the 2015 Dutch dietary guidelines. Because a higher diet quality, i.e. a higher adherence to the dietary guidelines, is associated with better health outcomes, a higher DHD2015-index score would also mean better outcomes on measures of health, such as all-cause mortality. The present study aimed to elucidate this by investigating the association between DHD2015-index score and mortality in the Dutch population using data from 97 999 participants in the Lifelines cohort study. For the analyses, Cox Proportional Hazards regression was used, whilst accounting for age, sex, physiological measurements, exercise, and biochemical and lifestyle variables. There was a strong negative association between DHD2015-index score and mortality. Hazard ratios for DHD2015-index scores below 60 were approximately 1.2x larger than the mean. Every 10 unit increase in DHD2015-index scores between 60 and 90 led to a 0.1 reduction in hazard ratio, and every 10 unit increase between 90 and the highest DHD2015-index scores led to a reduction in hazard ratios of 0.05. The hazard ratio for the lowest quartile of DHD2015-index scores was 1.14 (95% CI = 1.04-1.26), whereas that for the highest quartile was 0.88 (95% CI = 0.84-0.92). Our results show a clear inverse relationship between DHD2015-index score and all-cause mortality.

Obesity in European nursing homes participating in nutritionDay 2016-2021-Prevalence and resident characteristics

The objective of this study is to assess obesity prevalence and characterize European nursing home (NH) residents with obesity comprehensively. Cross-sectional nutritionDay data from 2016 to 2021. Descriptive characterization of European NH residents ≥65 years with and without obesity. Binomial logistic regression to identify factors associated with obesity. A total of 11 327 residents (73.8% female, 86.4 ± 7.9 years, mean body mass index 25.3 ± 5.4 kg/m2) from 12 countries were analysed. Obesity prevalence was 17.7%, mostly class I (13.0%). Taking ≥5 drugs/day (OR 1.633; 95% confidence intervals 1.358-1.972), female sex (1.591; 1.385-1.832), being bed/chair-bound (1.357; 1.146-1.606), and having heart/circulation/lung disease (1.276; 1.124-1.448) was associated with increased obesity risk, older age (0.951; 0.944-0.958), mild (0.696; 0.601-0.805) and severe (0.591; 0.488-0.715) dementia, eating less than ¾ of lunch on nutritionDay (0.669; 0.563-0.793), needing assistance for eating (0.686; 0.569-0.825), and being identified by NH staff at risk for (0.312; 0.255-0.380) or with malnutrition (0.392; 0.236-0.619) decreased obesity risk. Almost one in five residents in European NH participating in nutritionDay is affected by obesity. Through a wide exploratory analysis, including data from 12 European countries, we confirmed previous findings and identified additional factors associated with obesity that should be considered in the daily care of affected residents.

Efficacy and safety of tirzepatide versus placebo in overweight or obese adults without diabetes: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Tirzepatide was approved to treat type 2 diabetes and obesity, but its efficacy and safety in patients without diabetes has not been investigated.

AIM

This meta-analysis aimed to evaluate the efficacy and safety of tirzepatide compared to placebo in overweight or obese patients without diabetes.

METHOD

PubMed, Embase and Cochrane were searched on January 18, 2024. Randomized controlled trials (RCTs) that used tirzepatide in overweight or obese adults without diabetes were included. Efficacy outcomes included the proportion of participants achieving weight loss targets, changes in body weight (%), body mass index (BMI), waist circumference (WC), and blood pressure (BP). Safety outcomes were commonly reported adverse events. Standardized mean differences (SMD) or odds ratios (OR) with 95% confidence intervals (CIs) were used for continuous and dichotomous outcomes, respectively.

RESULTS

Three RCTs with 3901 participants were included. Tirzepatide was associated with increased proportion of participants achieving weight loss targets, reduced body weight (SMD - 1.61, 95% CI - 2.20 to - 1.02), BMI (SMD - 2.13, 95% CI - 3.08 to - 1.18), WC (SMD - 0.91, 95% CI - 1.14 to - 0.69), and BP versus placebo. However, the risk of adverse events such as nausea (OR 4.26, 95% CI 2.60 to 3.81), vomiting (OR 8.35, 95% CI 5.19 to 13.45), and diarrhea (OR 3.57, 95% CI 2.80 to 4.57) was significantly higher for tirzepatide versus placebo.

CONCLUSION

Tirzepatide significantly reduced weight and improved metabolic markers among overweight or obese without diabetes. However, increased adverse events highlights the need for benefits versus risks assessment before initiation and continuous monitoring.

Allometric multi-scaling of weight-for-height relation in children and adolescents: Revisiting the theoretical basis of body mass index of thinness and obesity assessment

The body mass index (BMI), defined as weight in kilograms divided by height in meters squared, has been widely used to assess thinness and obesity in all age groups, including children and adolescents. However, the validity and utility of BMI as a reliable measure of nutritional health have been questioned. This study discusses the mathematical conditions that support the validity of BMI based on population statistics. Here, we propose a condition defined as allometric uni-scaling to ensure the validity of BMI as an objective height-adjusted measure. Any given centile curve, including the median curve, in a weight-for-height distribution should be approximated using power-law functions with the same scaling exponent. In contrast, when the scaling exponent varies depending on the position of the centile curve, it is called allometric multi-scaling. By introducing a method for testing these scaling properties using quantile regression, we analyzed a large-scale Japanese database that included 7,863,520 children aged 5-17 years. We demonstrated the remarkable multi-scaling properties at ages 5-13 years for males and 5-11 years for females, and the convergence to uni-scaling with a scaling exponent close to 2 as they approached 17 years of age for both sexes. We confirmed that conventional BMI is appropriate as an objective height-adjusted mass measure at least 17 years of age, close to adulthood, for both males and females. However, the validity of BMI could not be confirmed in younger age groups. Our findings indicate that the growth of children's weight-for-height relation is much more complex than previously assumed. Therefore, a single BMI-type formula cannot be used to assess thinness and obesity in children and adolescents.

Risk of Cardiovascular Events in Metabolically Healthy Overweight or Obese Adults: Role of LDL-Cholesterol in the Stratification of Risk

The objective of this study was to investigate the longitudinal association of metabolically healthy overweight/obese adults with major adverse cardiovascular events (MACE) and the effect of LDL-cholesterol levels on this association. This study was conducted with 15,904 participants from the URRAH study grouped according to BMI and metabolic status. Healthy metabolic status was identified with and without including LDL-cholesterol. The risk of MACE during 11.8 years of follow-up was evaluated with multivariable Cox regressions. Among the participants aged <70 years, high BMI was associated with an increased risk of MACE, whereas among the older subjects it was associated with lower risk. Compared to the group with normal weight/healthy metabolic status, the metabolically healthy participants aged <70 years who were overweight/obese had an increased risk of MACE with an adjusted hazard ratio of 3.81 (95% CI, 1.34-10.85, p = 0.012). However, when LDL-cholesterol < 130 mg/dL was included in the definition of healthy metabolic status, no increase in risk was found in the overweight/obese adults compared to the normal weight individuals (hazard ratio 0.70 (0.07-6.71, p = 0.75). The present data show that the risk of MACE is increased in metabolically healthy overweight/obese individuals identified according to standard criteria. However, when LDL-cholesterol is included in the definition, metabolically healthy individuals who are overweight/obese have no increase in risk.

Associations between body mass index and all-cause mortality among individuals with psoriasis: results from the NHANES database retrospective cohort study

Background

Previous findings imply a potential positive association between BMI and all-cause mortality in individuals with psoriasis, yet direct evidence remains absent. This study aimed to fill this gap.

Methods

We utilized data from the National Health and Nutrition Examination Survey (NHANES) for the periods 2003-2006 and 2009-2014. Participants' BMI was categorized as lean (<25), overweight (25 ≤ BMI < 30), and obese (BMI ≥ 30). Psoriasis status was determined through self-reporting. The main outcome measured was all-cause mortality up to December 2019. We accounted for multiple covariates, such as sociodemographic factors and histories of smoking and alcohol consumption. Our statistical analyses mainly included Kaplan-Meier survival analysis, Restricted Cubic Spline (RCS) and Multivariate Cox Regression (MCR). We also applied propensity score matching (PSM) to verify the robustness of our findings.

Results

Among 22,876 participants, 618 (2.70%) reported a history of psoriasis. An overall effect from the MCR analysis showed that, among individuals with psoriasis, a higher baseline BMI was independently associated with an increased risk of all-cause mortality, noting a 5.5% rise in mortality risk per BMI unit [hazard ratio (HR) = 1.055, 95% CI: 1.004-1.110, p = 0.035]. This significant relationship persisted after PSM. A statistically significant positive correlation was consistent among males, smokers, and individuals younger than 60. However, no such association was found in individuals without a history of psoriasis. Additionally, no significant difference in mortality risk was found between lean and overweight groups with psoriasis, according to the RCS regression and stratified analysis.

Conclusion

Our findings indicated a trend that, higher BMIs significantly correlated with increased risks of all-cause mortality in people with psoriasis, particularly among obese ones. However, the impact of being overweight on this relationship remains underexplored. Moreover, the necessity to employ alternative metrics beyond BMI for body fat assessment to further investigate these associations is critical.

Body mass index and all-cause mortality in HUNT and UK biobank studies: revised non-linear Mendelian randomisation analyses

OBJECTIVES

To estimate the shape of the causal relationship between body mass index (BMI) and mortality risk in a Mendelian randomisation framework.

DESIGN

Mendelian randomisation analyses of two prospective population-based cohorts.

SETTING

Individuals of European ancestries living in Norway or the UK.

PARTICIPANTS

56 150 participants from the Trøndelag Health Study (HUNT) in Norway and 366 385 participants from UK Biobank recruited by postal invitation.

OUTCOMES

All-cause mortality and cause-specific mortality (cardiovascular, cancer, non-cardiovascular non-cancer).

RESULTS

A previously published non-linear Mendelian randomisation analysis of these data using the residual stratification method suggested a J-shaped association between genetically predicted BMI and mortality outcomes with the lowest mortality risk at a BMI of around 25 kg/m2. However, the 'constant genetic effect' assumption required by this method is violated. The reanalysis of these data using the more reliable doubly-ranked stratification method provided some indication of a J-shaped relationship, but with much less certainty as there was less precision in estimates at the lower end of the BMI distribution. Evidence for a harmful effect of reducing BMI at low BMI levels was only present in some analyses, and where present, only below 20 kg/m2. A harmful effect of increasing BMI for all-cause mortality was evident above 25 kg/m2, for cardiovascular mortality above 24 kg/m2, for cancer mortality above 30 kg/m2 and for non-cardiovascular non-cancer mortality above 26 kg/m2. In UK Biobank, the association between genetically predicted BMI and mortality at high BMI levels was stronger in women than in men.

CONCLUSION

This research challenges findings from previous conventional observational epidemiology and Mendelian randomisation investigations that the lowest level of mortality risk is at a BMI level of around 25 kg/m2. Our results provide some evidence that reductions in BMI will increase mortality risk for a small proportion of the population, and clear evidence that increases in BMI will increase mortality risk for those with BMI above 25 kg/m2.

Obesity and body mass index: Past and future considerations in osteoarthritis research

Obesity is an important topic for the osteoarthritis (OA) scientific community. However, the predominant use of body mass index (BMI) to define obesity in OA research is associated with uncertainties and limitations. These include an inability to discern fat and muscle mass, account for sex-differences in fat distribution, or identify adiposity-related health impairments. A focus on BMI in OA research may influence weight bias in clinical practice and impact disparities in access to effective OA treatments. To ensure that our understanding and approaches to improve health outcomes for individuals with or at risk for OA continues to advance in the next decade, future research will need to consider alternative measures beyond BMI for obesity identification and align with evolving obesity science. OA researchers must be aware of issues associated with weight stigma and work to minimize negative generalizations based on BMI.

Sarcopenia and Sarcopenic Obesity and Mortality Among Older People

Importance

Sarcopenia and obesity are 2 global concerns associated with adverse health outcomes in older people. Evidence on the population-based prevalence of the combination of sarcopenia with obesity (sarcopenic obesity [SO]) and its association with mortality are still limited.

Objective

To investigate the prevalence of sarcopenia and SO and their association with all-cause mortality.

Design, Setting, and Participants

This large-scale, population-based cohort study assessed participants from the Rotterdam Study from March 1, 2009, to June 1, 2014. Associations of sarcopenia and SO with all-cause mortality were studied using Kaplan-Meier curves, Cox proportional hazards regression, and accelerated failure time models fitted for sex, age, and body mass index (BMI). Data analysis was performed from January 1 to April 1, 2023.

Exposures

The prevalence of sarcopenia and SO, measured based on handgrip strength and body composition (BC) (dual-energy x-ray absorptiometry) as recommended by current consensus criteria, with probable sarcopenia defined as having low handgrip strength and confirmed sarcopenia and SO defined as altered BC (high fat percentage and/or low appendicular skeletal muscle index) in addition to low handgrip strength.

Main Outcome and Measure

The primary outcome was all-cause mortality, collected using linked mortality data from general practitioners and the central municipal records, until October 2022.

Results

In the total population of 5888 participants (mean [SD] age, 69.5 [9.1] years; mean [SD] BMI, 27.5 [4.3]; 3343 [56.8%] female), 653 (11.1%; 95% CI, 10.3%-11.9%) had probable sarcopenia and 127 (2.2%; 95% CI, 1.8%-2.6%) had confirmed sarcopenia. Sarcopenic obesity with 1 altered component of BC was present in 295 participants (5.0%; 95% CI, 4.4%-5.6%) and with 2 altered components in 44 participants (0.8%; 95% CI, 0.6%-1.0%). An increased risk of all-cause mortality was observed in participants with probable sarcopenia (hazard ratio [HR], 1.29; 95% CI, 1.14-1.47) and confirmed sarcopenia (HR, 1.93; 95% CI, 1.53-2.43). Participants with SO plus 1 altered component of BC (HR, 1.94; 95% CI, 1.60-2.33]) or 2 altered components of BC (HR, 2.84; 95% CI, 1.97-4.11) had a higher risk of mortality than those without SO. Similar results for SO were obtained for participants with a BMI of 27 or greater.

Conclusions and Relevance

In this study, sarcopenia and SO were found to be prevalent phenotypes in older people and were associated with all-cause mortality. Additional alterations of BC amplified this risk independently of age, sex, and BMI. The use of low muscle strength as a first step of both diagnoses may allow for early identification of individuals at risk for premature mortality.

Slim north, fat south: explaining regional differences in abnormal weights in Nigeria

Weight abnormalities (underweight, overweight, and obesity) can cause life-threatening ailments. This study investigates disparities in the prevalence of underweight, overweight, and obesity between northern and southern Nigeria and their associated factors. Using the 2018 Nigeria Demographic and Health Survey (NDHS), the study analysed a sample of 12,333 women with complete records of body mass index. The study found that southern women had lower odds of being underweight than women in the north, but the reverse was the case for overweight and obesity. The prevalence of underweight was 11.6%, and it varies from 6.9% in the southern state of Enugu to 31.6% in the northern state of Jigawa. The national prevalence of overweight was 17.9%, ranging from 6.7% in Jigawa State of the northern region to 39.9% in Lagos State of the south. Similarly, the prevalence of obesity in the north was 6.1% compared to 14.4% in the south, with Anambra State of the southern region recording the highest figure of 35.5% compared to 2.1% in the Yobe State of the northern region. In all, the rate of abnormal weight was significantly higher in the south than in the north. However, the type of weight abnormality varies between the two regions. Religion, education, use of contraceptives, and wealth were associated with the three forms of abnormal weights. However, while religion was significantly associated with obesity in the north, the association was not significant in the south. This study found that wealth and education have dissimilar influences on overnutrition. While the odds of being overweight and obese increase with wealth, being educated up to a secondary level significantly reduces the odds in Nigeria and across the two regions.

Impact of Pre-Diagnostic Risk Factors on Short- and Long-Term Ovarian Cancer Survival Trajectories: A Longitudinal Observational Study

Tumor- and treatment-related factors are established predictors of ovarian cancer survival. New studies suggest a differential impact of exposures on ovarian cancer survival trajectories (i.e., rapidly fatal to long-term disease). This study examined the impact of pre-diagnostic risk factors on short- and long-term ovarian cancer survival trajectories in the Canadian context. This population-based longitudinal observational study included women diagnosed with invasive epithelial ovarian cancer from 1995 to 2004 in Ontario. Data were obtained from medical records, interviews, and the provincial cancer registry. Extended Cox proportional hazard models estimated the association between risk factors and all-cause and ovarian cancer-specific mortality by survival time intervals (<3 years (i.e., short-term survival), 3 to <6 years, 6 to <10 years, and ≥10 years (i.e., long-term survival)). Among 1421 women, histology, stage, and residual disease were the most important predictors of all-cause mortality in all survival trajectories, particularly for short-term survival. Reproductive and lifestyle factors did not strongly impact short-term overall survival but were associated with long-term overall survival. As such, among long-term survivors, history of breastfeeding significantly decreased the risk of all-cause mortality (HR 0.65; 95% CI 0.46, 0.93; p < 0.05), whereas smoking history (HR 1.75; 95% CI 1.27, 2.40; p < 0.05) and obesity (HR 1.81; 95% CI 1.24, 2.65; p < 0.05) significantly increased the risk of all-cause mortality. The findings were consistent with ovarian cancer-specific mortality. These findings suggest that pre-diagnostic exposures differentially influence survival time following a diagnosis of ovarian cancer.

Body Mass Index, Quality of Life and Activity Limitation Trajectories over 2 Years in Patients with Knee or Hip Osteoarthritis: A Dual Trajectory Approach Based on 4265 Patients Included in the AktivA Quality Register

(1) Background: Recent studies claim that weight-neutral approaches emphasizing physical activity might be as effective as weight-loss-centered approaches for improving pain and physical function in patients with knee and hip osteoarthritis. The objectives were to identify distinctive groups of individuals with similar BMI, quality of life and activity limitation trajectories over two years, to compare the overall differences between BMI trajectory groups for baseline variables and to explore the probabilities of the quality of life and activity limitation trajectory groups conditional on the BMI group. (2) Methods: Baseline data for age, gender, BMI, quality of life, activity limitations, pain, general health, knee or hip osteoarthritis and follow-up data on BMI, quality of life and activity limitations at 3, 12 and 24 months were retrieved from the "Active with osteoarthritis" (AktivA) electronic quality register. Group-based trajectory modeling was used to identify distinct trajectories for BMI, quality of life and activity limitations. (3) Results: 4265 patients were included in the study. Four distinct BMI trajectories were identified, normal weight (31%), slightly overweight (43%), overweight (20%) and obese (6%). At baseline, there were highly significant differences between all BMI groups, pain increased and age and general health decreased with higher BMI. Irrespective of weight category, minimal changes in BMI were found over the two-year follow-up period. Over 80% of the participants showed moderate-to-considerable improvements both in quality of life and activity limitations. (4) Conclusions: Almost 70% of the participants belonged to the overweight trajectories. Despite no significant weight reduction over the two years, eight in every 10 participants improved their quality of life and reduced their activity limitations after participating in the AktivA program.