A U-shaped association between serum albumin with total triiodothyronine in adults

Association of weight-adjusted waist index with all-cause mortality among non-Asian individuals: a national population-based cohort study

INTRODUCTION

The Weight-Adjusted Waist Index (WWI) is a new indicator of obesity that is associated with all-cause mortality in Asian populations. Our study aimed to investigate the linear and non-linear associations between WWI and all-cause mortality in non-Asian populations in the United States, and whether WWI was superior to traditional obesity indicators as a predictor of all-cause mortality.

METHODS

We conducted a cohort study using data from the 2011-2018 National Health and Nutrition Examination Survey (NHANES), involving 18,592 participants. We utilized Cox proportional hazard models to assess the association between WWI, BMI, WC, and the risk of all-cause mortality, and performed subgroup analyses and interaction tests. We also employed a receiver operating characteristics (ROC) curve study to evaluate the effectiveness of WWI, BMI, and WC in predicting all-cause mortality.

RESULTS

After adjusting for confounders, WWI, BMI, and WC were positively associated with all-cause mortality. The performance of WWI, BMI, and WC in predicting all-cause mortality yielded AUCs of 0.697, 0.524, and 0.562, respectively. The data also revealed a U-shaped relationship between WWI and all-cause mortality. Race and cancer modified the relationship between WWI and all-cause mortality, with the relationship being negatively correlated in African Americans and cancer patients.

CONCLUSIONS

In non-Asian populations in the United States, there is a U-shaped relationship between WWI and all-cause mortality, and WWI outperforms BMI and WC as a predictor of all-cause mortality. These findings may contribute to a better understanding and prediction of the relationship between obesity and mortality, and provide support for effective obesity management strategies.

The association between weight-adjusted-waist index and stress urinary incontinence in female adults: a population-based study

INTRODUCTION

Obesity has a significant impact on female stress urinary incontinence. The weight-adjusted-waist index (WWI), a newly explored metric for measuring physical obesity and stress urine incontinence, has not been investigated.

METHODS

Cross-sectional data were obtained from the 2011 to 2018 National Health and Nutrition Examination Survey (NHANES) of participants with complete data for WWI and SUI. The independent connection between WWI and SUI was examined using weighted multivariable logistic regression analyses. Smoothed curve fitting was used to study their relationship. In addition, subgroup analyses were performed, and interaction tests were undertaken.

RESULTS

In 2,361 female participants over 20, WWI and SUI showed a positive association. Model 3 found that for each one-unit increase in WWI, SUI prevalence increased by 38% [1.38 (1.20, 1.59)]. The prevalence of SUI was 84% higher among participants in the highest quartile of WWI compared to those in the lowest quartile [1.84 (1.32, 2.57)]. Observed nonlinear positive correlation between WWI and SUI was revealed through smoothed curve fitting. In addition, we found that WWI was more strongly associated with SUI than traditional indicators of obesity, including BMI and weight.

CONCLUSIONS

Females with higher weight-adjusted waist index levels were more likely to develop stress urinary incontinence and have a stronger correlation than traditional indicators of obesity. According to our research, WWI may help detect women's stress urinary incontinence (SUI), and managing obesity through the WWI index may reduce SUI prevalence rates.

Associations of cereal fiber intake with rheumatoid arthritis mediated by dietary inflammatory index: insights from NHANES 2011-2020

Rheumatoid Arthritis (RA) is an increasingly prevalent inflammatory disorder worldwide. Its complex etiology has recently brought dietary factors, particularly fiber intake, into focus as potential influencers. Our study investigates the intricate relationship between various sources of dietary fiber and RA, emphasizing the mediating role of the Dietary Inflammatory Index (DII). Leveraging data from the National Health and Nutrition Examination Survey spanning 2011 to 2020. We meticulously assessed dietary fiber intake through dual 24 h dietary recall interviews, while RA diagnoses were established based on comprehensive medical surveys. The relationships between fiber intake, RA prevalence, and DII mediation were analyzed using sophisticated multivariate logistic regression and mediation analysis. Among our study cohort, 7% were diagnosed with RA. We observed a notable inverse correlation between increased total fiber intake, particularly 5 g/day increments, and the incidence of RA, with cereal fiber intake emerging as the primary mitigating factor. Intriguingly, the DII played a significant role in mediating this association, especially regarding cereal fiber. Our findings reveal a significant association between higher cereal fiber consumption and a reduced prevalence of RA. Additionally, the DII stands out as a pivotal mediator in this relationship, highlighting dietary management's critical role in preventing and managing RA.

Association between lung function and bone mineral density in children and adolescents: Insights from the NHANES

Bone development and lung function are integral to child and adolescent health. Both influence an individual's overall well-being and potentially affect long-term health. Utilizing a comprehensive dataset from the National Health and Nutrition Examination Survey, this study aims to elucidate the relationship between lung function and bone mineral density (BMD) in a representative sample of children and adolescents. The analysis covered 3410 participants aged 8 to 19 years. We employed weighted multivariate linear regression and restricted cubic spline curve visualizations to explore the intricate association between lung function metrics, particularly first-second expiratory volume 1 second/forced vital capacity ratio, and lumbar BMD. Our data indicated a positive association between lung function and lumbar BMD in children and adolescents. Specifically, higher lung function metrics were linked with increased lumbar BMD. This association was more pronounced in younger participants or those with a lower body mass index. A significant positive relationship exists between lung function and BMD in the pediatric population. Recognizing this association is crucial for holistic health strategies for children and adolescents. This study underscores the need for integrated health monitoring during formative years, which can influence health trajectories as these individuals transition to adulthood.

Association between urine caffeine metabolites and bone mineral density: A population-based study

The association between coffee intake and bone mineral density (BMD) remains a subject of debate in epidemiological research. Furthermore, the potential relationship between BMD and urine caffeine or caffeine metabolites has not yet been explored. Therefore, the present study aimed to investigate the possible association between BMD and urine caffeine and its metabolites in U.S. adults. We employed multivariate linear and logistic regression models to analyze the relationship between urine caffeine and caffeine metabolites and lumbar BMD using data from the National Health and Nutrition Examination Survey (NHANES) from 2009 to 2014. Additionally, fitted smoothing curves and generalized additive models were used. After adjusting for several factors, we found no significant association between urine caffeine and its metabolites and BMD. However, subgroup analyses stratified by gender and ethnicity showed that the relationship between urine caffeine and its metabolites and lumbar BMD remained consistent. Our investigation revealed that the inflection points for the U-shaped relationship between urinary theophylline and paraxanthine and BMD were observed at levels of 0.006 mmol/L for theophylline and 0.052 mmol/L for paraxanthine. In this cross-sectional study, we found no significant correlation between urine caffeine and its metabolites and BMD. However, more research is required to confirm our findings, as well as to investigate the underlying mechanisms.

Associations between systemic immune-inflammation index and abdominal aortic calcification: Results of a nationwide survey

BACKGROUND AND AIM

The Systemic Immune-Inflammation Index (SII) is a novel index of inflammation assessment that appears to be superior to the common single blood index in the assessment of cardiovascular disease. The purpose of this study was to investigate the association between SII and abdominal aortic calcification (AAC) in adults.

METHODS AND RESULTS

Multivariate logistic regression, sensitivity analysis, and smoothing curve fitting were used to investigate the relationship between SII and AAC based on data from the National Health and Nutrition Examination Survey (NHANES) 2013-2014. Subgroup analysis and interaction tests were used to investigate whether this association was stable across populations. There was a positive association between SII and ACC in 3036 participants >40 years of age. In the fully adjusted model, each 100-unit increase in SII was associated with a 4% increase in the risk of developing severe AAC [1.04 (1.02, 1.07)]. Participants in the highest quartile of SII had a 47% higher risk of developing severe AAC than those in the lowest quartile [1.47 (1.10, 1.99)]. This positive association was more pronounced in older adults >60 years of age.

CONCLUSIONS

SII is positively associated with AAC in US adults. Our findings imply that SII has the potential to improve AAC prevention in the general population.

Inverted U-shaped relationships between bone mineral density and VCTE-quantified degree of hepatic steatosis in adolescents: Evidence from the NHANES

INTRODUCTION

There may be inaccuracies in hepatic steatosis in past research assessing the relationship between bone metabolism and liver steatosis. The goal of the current research was to look at the associations between bone mineral density (BMD) and the hepatic steatosis and fibrosis as detected by vibration-controlled transient elastography (VCTE) in teenagers in the United States.

METHODS

Weighted multiple linear regression models and smoothed curve fitting were used to investigate the association between BMD and the degree of hepatic steatosis and fibrosis in adolescents.

RESULTS

In 829 adolescents aged 12-19 years we found a negative association between total BMD and CAP (controlled attenuation parameter) [-32.46 (-58.98, -9.05)] and a significant positive association between lumbar BMD and LSM (liver stiffness measurement) [1.35 (0.19, 2.51)]. The inverted U-shaped relationships were founded between total BMD, lumbar BMD, pelvis BMD, and CAP with inflection points of 221.22 dB/m, 219.88 dB/m, and 216.02 dB/m, respectively.

CONCLUSIONS

In adolescents, higher BMD is significantly associated with lower levels of hepatic steatosis and higher levels of liver stiffness.

Dietary inflammatory potential and biological aging among US adults: a population-based study

OBJECTIVES

The rate of biological aging is influenced by various factors such as genetics, environment, and diet. The dietary inflammatory index (DII) is strongly associated with various chronic diseases. The aim of this study was to investigate the association between DII and biological aging in US adults using quantitative indicators.

METHODS

Based on data from the National Health and Nutrition Examination Survey (NHANES) 1999-2018, weighted multiple linear regression models, generalized weighted models, and smoothed fitted curves were used to investigate the linear and nonlinear relationships of DII with four biological markers of aging (biological age, phenotypic age, telomere length, and serum klotho concentration).

RESULTS

A total of 35,575 adult participants with complete data were included in the study. After adjusting for all confounders, significant positive correlations were found between DII with biological age [0.070 (0.045, 0.095)] and phenotypic age [0.421 (0.371, 0.471)], with an increase of 0.07 and 0.42 years in biological age and phenotypic age, respectively, for each increase in DII score. The negative correlations between DII with telomere length [ - 0.005 ( - 0.008, - 0.002)] and klotho [ - 3.874 ( - 7.409, - 0.338)] were significant only in partially adjusted models and differed across subgroups.

CONCLUSIONS

In the current study, higher DII scores (greater pro-inflammatory dietary potential) were associated with biological aging. These findings may contribute to the development of aging prevention strategies through dietary interventions.

Associations between smoking status and infertility: a cross-sectional analysis among USA women aged 18-45 years

Background

Although many studies have proven the harmful effects of smoking on human health, the associations between smoking status and infertility are limited in large epidemiologic studies. We aimed to investigate the associations between smoking status and infertility among child-bearing women in the United States of America (USA).

Methods

A total of 3,665 female participants (aged 18-45) from the National Health and Nutrition Examination Survey (NHANES) (2013-2018) were included in this analysis. All data were survey-weighted, and corresponding logistic regression models were performed to investigate the associations between smoking status and infertility.

Results

In a fully adjusted model, the risk of infertility was found to be increased by 41.8% among current smokers compared to never smokers (95% CI: 1.044-1.926, P=0.025). In the subgroup analysis, the odds ratios (95% CI) of the risk of infertility for current smokers were 2.352 (1.018-5.435) in the unadjusted model for Mexican American, 3.675 (1.531-8.820) in the unadjusted model but 2.162 (0.946-4.942) in fully adjusted model for people aged 25-31, 2.201 (1.097-4.418) in the unadjusted model but 0.837 (0.435-1.612) in fully adjusted model for people aged 32-38.

Conclusion

Current smokers was associated with a higher risk of infertility. The underlying mechanism of these correlations still needs more research. Our findings indicated that quitting smoking may serve as a simple index to reduce the risk of infertility.

Associations between weight-adjusted waist index and fractures: a population-based study

INTRODUCTION

The weight-adjusted waist circumference index (WWI) is a novel obesity evaluation indicator that appears to be superior to body mass index (BMI) and waist circumference (WC) in evaluating muscle and fat mass. The purpose of this study was to investigate the association between WWI and fractures among adults.

METHODS

In this cross-sectional study, multivariate logistic regression and smoothed curve fitting were used to investigate linear and nonlinear associations between WWI and fractures, based on data from 28,679 adult participants in the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018.

RESULTS

After adjusting for all covariates, the prevalence of hip/wrist/spine fractures among all participants was 1.09%, 8.87%, and 1.97%, respectively. A 1-unit increase in WWI was associated with a 5% increase in the odds of hip fractures [1.05 (1.01, 1.10)], and a 9% increase in the odds of spine fractures [1.09 (1.06, 1.13)], but not with the prevalence of wrist fractures [0.97 (0.94, 1.06)].

CONCLUSIONS

Higher WWI was associated with an increased prevalence of hip fracture and spine fracture, but not wrist fracture.

BMI, socioeconomic status, and bone mineral density in U.S. adults: Mediation analysis in the NHANES

Introduction

The mechanism by which socioeconomic status (SES) affects bone mineral density (BMD) remains unknown, and body mass index (BMI) may be a potential mediator. The purpose of this study was to investigate whether BMI mediates the relationship between SES [education level and poverty income ratio (PIR)] and lumbar BMD and the proportion it mediates.

Methods

This study included a total of 11,075 adults from the National Health and Nutrition Examination Survey (NHANES). Lumbar BMD was measured at the lumbar spine by dual-energy X-ray absorptiometry (DXA). Multivariate linear regression and smoothing curve fitting were used to investigate the relationship between SES and lumbar BMD. Mediator analysis was used to investigate the proportion of BMI mediating the association between SES and BMD.

Results

In the fully adjusted model, there was a positive correlation between SES and BMD (education level: β = 0.025, 95% CI: 0.005, 0.045; PIR: β = 0.007, 95% CI: 0.002, 0.011). Mediation analysis showed that BMI mediated the relationship between PIR, education level, and lumbar BMD with a range of mediation proportions from 13.33 to 18.20%.

Conclusion

BMI partially mediated the positive association between SES and BMD, and this association may be largely mediated by factors other than BMI.

Association of family income to poverty ratio and vibration-controlled transient elastography quantified degree of hepatic steatosis in U.S. adolescents

INTRODUCTION

Inequality in socioeconomic status plays an important role in the prevalence of metabolic diseases in adolescents. The purpose of this study was to explore the association between family income and the degree of hepatic steatosis quantified by vibration-controlled transient elastography (VCTE) among U.S. adolescents.

METHODS

This cross-sectional study included two cycles of the National Health and Nutrition Examination Survey (NHANES) 2017-2020. Multivariate linear regression and smoothing curve fitting were used to investigate the linear and nonlinear relationship between PIR and hepatic steatosis, respectively. Subgroup analysis and interaction tests were used to test whether this relationship was stable across groups.

RESULTS

Of the 1,574 adolescent participants, 456 lived in poor households and 307 lived in wealthy households. After adjusting for all covariates, PIR (Ratio of family income to poverty) was significantly negatively associated with the degree of hepatic steatosis [-4.78 (-7.39, -2.17)], and this remained stable after converting PIR to a categorical variable. In addition, this significant negative association was more pronounced in women [-7.62 (-11.38, -3.87)], non-Hispanic blacks [-7.19 (-14.43, 0.06)], Mexican Americans [-6.80 (-13.63, 0.03)], and participants with BMI >30 cm² [-10.83 (-19.70, -1.96)].

CONCLUSIONS

PIR was significantly and negatively associated with the degree of hepatic steatosis in US adolescents. Additional prospective studies are needed to confirm our findings.

The Tri-iodothyronine (T3) Level Is a Prognostic Factor for Patients With Advanced NSCLC: Receiving Immune Checkpoint Inhibitors and Is Associated With Liver Metastasis

BACKGROUND

Endocrine hormones influence tumor progression and the response to treatment. Despite the importance of immune checkpoint inhibitors (ICIs) as treatments for advanced non-small cell lung cancer (NSCLC), few studies have explored the effects of hormone levels in NSCLC patients on the effectiveness of ICI therapies. We thus investigated the effects of baseline blood markers in patients with advanced NSCLC on ICI treatments.

METHODS

Patients with advanced NSCLC who received programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) inhibitors at Chungnam National University Hospital between December 2016 and November 2020 and who lacked any history of thyroid gland-related diseases were analyzed retrospectively. We collected clinical information and baseline laboratory data, including the levels of endocrine hormones, cytokines, complete blood counts (CBCs), and peripheral blood chemistry panels. We explored the relationships of hormone levels with clinical outcomes (overall survival [OS], progression-free survival [PFS], and best response), liver metastasis, and blood markers using the Kaplan-Meier method, Cox's proportional hazards regression, and logistic regression.

RESULTS

A total of 113 patients were enrolled. A shorter PFS was independently associated with liver metastasis, higher cortisol levels, and lower hemoglobin (Hb) levels; a shorter OS was associated with liver metastasis, lower tri-iodothyronine (T3) levels, higher lactate dehydrogenase (LDH) levels, and lower albumin levels. Patients with low T3 levels exhibited a shorter PFS and OS, and a poorer best response. Patients with low T3 levels tended to have higher disease progression rates, lower levels of adrenocorticotropic hormone (ACTH), C-peptide, albumin, Hb, and neutrophil-to-lymphocyte ratio, and higher levels of interleukin (IL)-6, white blood cells, platelets, compared with those with normal T3 levels. We found a significant association between a low T3 level and liver metastasis.

CONCLUSIONS

We found the baseline T3 level was associated with both prognosis and the response to ICIs in patients with advanced NSCLC, probably reflecting impaired liver function and systemic inflammation induced by the interaction of T3 with other biomarkers, such as IL-6, ACTH, cortisol, C-peptide, Hb, LDH, and albumin.

Inverse association between low-density lipoprotein cholesterol and bone mineral density in young- and middle-aged people: The NHANES 2011–2018

Objectives

Low-density lipoprotein cholesterol (LDL-C) plays an essential part in bone metabolism. However, the correlation between LDL-C levels and bone mineral density (BMD) is still controversial. This study aimed to explore the relationship between LDL-C levels and lumbar BMD in young- and middle-aged people.

Methods

We conducted a cross-sectional study comprising 4,441 participants aged 20–59 from the National Health and Nutrition Examination Survey (NHANES). LDL-C levels and lumbar BMD were used as independent and dependent variables, respectively. We evaluated the correlation between LDL-C levels and lumbar BMD through a weighted multivariate linear regression model. We performed a subgroup analysis of the relationship between LDL-C levels and lumbar BMD based on age, gender, and body mass index (BMI).

Results

After adjusting for confounding factors, LDL-C levels were negatively correlated with lumbar BMD. In subgroup analyses stratified by gender, this negative association was statistically significant in men and women. In the subgroup analysis stratified by age, a negative connection existed in people aged 30–49 years. In the subgroup analysis divided by BMI, there was an inverse correlation in overweight people (25 ≤ BMI < 30).

Conclusions

Our research observed an inverse association between LDL-C levels and lumbar BMD in young- and middle-aged people, especially in people aged 30–49 years and who are overweight. Close monitoring of BMD and early intervention may be required for these people.