Is assessing the degree of hepatic steatosis and fibrosis based on index calculations the best choice for epidemiological studies?

Associations between waist-to-height ratio and abdominal aortic calcification: A cross-sectional study

Waist-to-height ratio (WtHR) is a validated biomarker of central obesity that appears to be preferable to other body composition measurements in the evaluation of cardiovascular disease. The goal of this research was to explore the connection between WtHR and abdominal aortic calcification (AAC) among adults. On the basis of data from the 2013 to 2014 National Health and Nutrition Examination Survey, multivariate logistic regression, sensitivity analysis, as well as smoothed curve fitting were used to evaluate the connection between WtHR and AAC. Subgroup analyses along with interaction tests were done to see if this link was consistent across populations. Among 3079 participants aged >40 years, there was a negative association between WtHR and ACC. Each 1-unit emergence of WtHR was related to a 2% reduction in the probability of severe AAC in the entirely adjusted model (odds ratio = 0.02, 95% confidence interval: [0.00-0.12]). Participants in the highest WtHR quartile were 39% less likely to acquire severe AAC compared with those in the lowest quartile. (odds ratio = 0.61, 95% confidence interval: [0.37-1.00]). This negative association was more pronounced in the diabetes subgroup. We discovered a reversed U-shaped association between WtHR as well as AAC score utilizing a 2-stage linear regression model, with an intersection point of 0.56. WtHR was negatively associated with AAC among US adults.

Association between hepatic steatosis and fibrosis and arthritis among US adults: A population-based study

BACKGROUND

Lipid metabolism factors may play a role in the development of arthritis and hepatic steatosis and fibrosis. The aim of this study was to explore the potential association between arthritis and hepatic steatosis and liver fibrosis.

MATERIALS AND METHODS

The nationally representative sample from the National Health and Nutrition Examination Survey was analyzed, with data on arthritis diagnosis, subtype, and liver status obtained. Liver status was assessed using transient elastography. Hepatic steatosis was defined as a Controlled Attenuation Parameter (CAP) score ≥263 dB/m, and liver fibrosis status was defined as F0‒F4. Logistic regression models and subgroup analyses stratified by sex were used to evaluate the associations. Smooth curve fitting was used to describe the associations.

RESULTS

The present study of 6,840 adults aged 20 years or older found a significant positive correlation between arthritis and CAP in multivariate logistic regression analysis (β = 0.003, 95 % CI 0.001 to 0.0041, p < 0.001). Participants with arthritis had a higher risk of hepatic steatosis (OR = 1.248, 95 % CI 1.036 to 1.504, p = 0.020), particularly those with osteoarthritis or degenerative arthritis, but not rheumatoid arthritis (p = 0.847). The positive correlation was maintained in females (β = 0.004, 95 % CI 0.002 to 0.006, p < 0.001), but not in males. There was no significant relationship between arthritis and liver fibrosis (p = 0.508).

CONCLUSION

This study indicates that there is a positive correlation between arthritis and hepatic steatosis, particularly in females. Nonetheless, there is no significant relationship between arthritis and the risk of liver fibrosis.

Association of hepatic steatosis and liver fibrosis with chronic obstructive pulmonary disease among adults

With high prevalence and substantial mortality, metabolic dysfunction-associated steatotic liver disease and chronic obstructive pulmonary disease (COPD) are significant public health concerns. Utilizing a large, population-based dataset from the National Health and Nutrition Examination Survey, our study probes the relationship between COPD prevalence and hepatic steatosis and fibrosis, as measured by Vibration-Controlled Transient Elastography. We analyzed data from 693 individuals with COPD and 7229 without. Through weighted multivariate logistic regression analysis, a restricted cubic spline curve, and threshold effect analysis, we investigated the correlation between the severity of hepatic steatosis and fibrosis and the presence of COPD. Our findings revealed a positive correlation between the controlled attenuation parameter (CAP) and COPD prevalence [OR = 1.03 (95% CI 1.01, 1.05)], even after multivariate adjustment. Furthermore, we observed a U-shaped association between CAP and COPD, where the inflection point, CAP value of 264.85 dB/m, corresponded to the lowest COPD prevalence. Our study emphasizes a substantial and complex link between hepatic steatosis and COPD. These findings urge healthcare professionals to factor liver health into COPD management and prompt further exploration into the underlying mechanisms. This could pave the way for the development of improved prevention and treatment strategies.

Nonlinear Relationship Between Systemic Immune-Inflammation and Hepatic Steatosis: A Population-Based Study in China

Background

Studies on the associations between Systemic Immune-Inflammation (SII) and hepatic steatosis in China are still lacking. It is necessary to clarify the relationship between SII and hepatic steatosis in the Chinese population.

Methods

This study was conducted from January 2022 to December 2022. A total of 37,095 participants were enrolled, among them, with 20,709 (55.83%) being males, and 16,386 (44.17%) being females. Physical and biochemical indicators were measured during a morning health examination after the examinees had fasted overnight. Diagnoses of hepatic steatosis were determined using an ultrasound test in accordance with the Chinese Guideline. Analysis of variance and chi-square tests were used to analyze the association between SII and hepatic steatosis. Stratification analyses were conducted based on age, gender, and obese status. Restricted cubic spline regression was also performed to explore the shapes of associations between SII and hepatic steatosis.

Results

The average age of the 37,095 participants was 44.78 years old, with those with hepatic steatosis (11,599 (31.27%)) averaging 47.06 years old and those (25,496 (68.73%)) in the control group averaging 43.73 years old. SII was positively associated with hepatic steatosis. This association remained significant after conducting stratification analysis by age and gender. The inflection points in the inverted U-shaped curve for the relationship between SII and hepatic steatosis were 399.78 for gender (1000 cells /µL)(nonlinear P<0.01, OR=1.31 (male), 1.00 (female)) and 385.79 for age (1000 cells /µL)(nonlinear P<0.01, OR=1.35 (18~44 years old), 1.87 (45~59 years old), 1.93 (60~ years old)).

Conclusion

SII is an independent risk factor for hepatic steatosis, and this effect appears to be stronger in subjects with BMI <28 kg/m2. The nonlinear relationship between SII and hepatic steatosis, characterized by an inverted U-shaped distribution, may serve as a reference for diagnosing and evaluating hepatic steatosis.

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.

New insights into metabolic dysfunction-associated steatotic liver disease and oxidative balance score

Background

The relationship between oxidative stress and metabolic dysfunction-associated steatotic liver disease (MASLD) has not been studied, which remains inadequately recognized. This is a cross-sectional study in a US adult population to explore the relationship between MASLD and oxidative balance scores (OBS), which containing integrating dietary nutrition and lifestyle factors.

Methods

We analyzed data from National Health and Nutrition Examination Survey during 2017-2018. Multivariate logistic regression, restricted cubic spline curve (RCS) and subgroup analysis were used to investigate the association between OBS and MASLD. Cox regression analysis was utilized to assess the association between OBS and all-cause mortality among individuals.

Results

The multivariable-adjusted odds ratio (OR) and 95% confidence interval (CI) for the highest quartile of OBS (Q4) was 0.30 (0.12, 0.77) (p = 0.012) compared to the lowest quartile of OBS (Q1). The RCS regression and subgroup analysis indicated an inverted relationship between OBS and the development of MASLD. The OBS Q4 group (HR: 0.15, 95% CI: 0.03-0.87; p = 0.035) exhibited a lower risk of all-cause death than the Q1 group.

Conclusion

OBS is statistically significantly and negatively correlated with the risk of MASLD and all-cause mortality in US adults. More prospective investigations are required to substantiate our findings.

The association between weight-adjusted-waist index and self-reported infertility among women of reproductive age in the United States

AIM

This study aimed to determine whether the weight-adjusted-waist index (WWI) affected infertility in women of childbearing age in the United States.

METHODS

In this study, a database from the 2013 to 2018 National Health and Nutrition Examination Survey (NHANES) was used. We analyzed 3374 participants' data cross-sectionally. The survey used WWI and fertility status as independent and dependent variables. To determine the effect of WWI, an analysis of the independent relationship between WWI and infertility was conducted using weighted multivariable logistic regression and a generalized additive mode (GAM). A smooth curve fitting test was used to calculate whether there was a linear association between WWI and the incidence rate of infertility, as well as subgroup analyses and interaction tests.

RESULTS

The prevalence of infertility was 10.19% among 3374 participants. Higher WWI quartiles were associated with higher infertility rates. Based on a fully adjusted model, the effects of WWI on fertility were positive (odds ratio = 1.39, 95% confidence interval: 1.17-1.66). As a result of smooth curve fitting, the association was linear across the entire WWI. Different characteristics were associated with different risks of infertility in subgroup analysis.

CONCLUSION

Among women of reproductive age in the United States, WWI levels were positively associated with infertility. This relationship needs to be confirmed by further studies.

Threshold effects and inflection points of flavonoid intake in dietary anti-inflammatory effects: Evidence from the NHANES

Flavonoids have been shown to be beneficial in a variety of inflammatory and metabolic diseases because of their anti-inflammatory and antioxidant properties. However, previous epidemiological studies have only demonstrated a negative correlation between flavonoid intake on inflammatory markers, and the optimal intake of dietary flavonoids and subclasses in terms of dietary anti-inflammatory efficacy remains undetermined. This study was based on 3 cycles (2007-2010, 2017-2018) of the National Health and Nutrition Examination Survey and the corresponding expanded flavonoid database. Weighted multiple linear regression was used to assess linear relationships between flavonoid intake and Dietary inflammation index (DII). Smoothed curve fit and a generalized additive model were used to investigate the nonlinear relationships and threshold effects, the 2-tailed linear regression model was used to find potential inflection points. A total of 12,724 adults were included in the study. After adjusting for potential confounders, flavonoid intake was significantly associated with DII, with the strongest negative association effect for flavonols (-0.40 [-0.45, -0.35]). In subgroup analyses stratified by sex, race, age, body mass index, education levels, and diabetes, flavonol intake maintained a significant negative linear correlation with DII. In addition, we found significant nonlinear relationships (L-shaped relationships) and threshold effects between total flavonoids, flavan-3-ols, and flavanols and DII, with inflection points of 437.65 mg/days, 157.79 mg/days, and 46.36 mg/days, respectively. Our results suggest a threshold for the dietary anti-inflammatory capacity of flavonoid intake in U.S. adults.

Association between nineteen dietary fatty acids and hearing thresholds: findings from a nationwide survey

INTRODUCTION

Hearing loss is a prevalent health concern, and dietary factors, such as fatty acid intake, may play a role in its development. The current study aimed to investigate the association between the intake of dietary fatty acids and hearing thresholds among U.S. adults.

METHODS

The researchers examined data from the National Health and Nutrition Examination Survey (NHANES), including 7,623 participants with available dietary fatty acid intake and audiometry data. Dietary fatty acid intake was assessed using dietary recalls, and hearing thresholds were measured using pure-tone audiometry. Multivariate linear regression models and smoothing curve fitting were utilized to explore the associations between dietary fatty acid intake and hearing thresholds, adjusting for relevant covariates.

RESULTS

This study reveals a direct association between both low and high frequency pure tone average (PTA) hearing thresholds and the dietary intake of total saturated fatty acids (SFAs) and total polyunsaturated fatty acids (PUFAs). Conversely, the intake of total monounsaturated fatty acids (MUFAs) demonstrates an inverted U-shaped correlation with low-frequency and high-frequency PTA hearing thresholds, having inflection points at 11.91 (energy (%)) and 10.88 (energy (%)), respectively.

CONCLUSION

Dietary intake of certain fatty acids may influence hearing thresholds in adults.

Associations between weight-adjusted waist index and bone mineral density: results of a nationwide survey

BACKGROUND

The weight-adjusted waist circumference index (WWI) is a novel obesity indicator that offers improved accuracy in assessing both muscle and fat mass compared to traditional measures. This study aimed to investigate the association between WWI and bone mineral density (BMD) in adults.

METHODS

Weighted multivariate logistic regression, subgroup analysis, interaction tests and restricted cubic spline (RCS) curves were used to explore the relationship between WWI and BMD based on data from the National Health and Nutrition Examination Survey (NHANES).

RESULTS

This study had 40,568 individuals in total. At all four measurement sites, we detected a negative linear correlation between WWI and BMD. Even when quartile factors for WWI were created, this unfavorable connection maintained. In comparison to those in the lowest quartile, those in the highest percentile of WWI showed declines in lumbar BMD of 0.08 g/cm2 and femoral neck BMD of 0.03 g/cm2, respectively. This adverse correlation, nevertheless, differed among several categories.

CONCLUSIONS

Our findings suggest an adverse correlation between WWI and BMD among US adults. Employing WWI as a tool for osteoporosis prevention in the general population may enhance interventions.

Association between bone mineral density and cardiovascular disease in older adults

Background and aims

Cardiovascular disease and osteoporosis are common diseases in older adults with high morbidity. The study on the interaction between the two in pathogenic mechanisms has been paid much attention by the majority of researchers. This study aimed to explore the relationship between bone mineral density and cardiovascular disease in older adults.

Methods

The primary data was downloaded from the National Health and Nutrition Examination Survey database of the United States. Multivariate logistic regression model, generalized additive model, and smooth curve fitting were used to explore the relationship between bone mineral density and cardiovascular events risk. When a curve relationship was found, a two-piecewise linear model was used to calculate the inflection point. In addition, subgroup analysis was also performed.

Results

A total of 2097 subjects were included in this study. After adjusting for potential confounders, no significant association was found between lumbar bone mineral density and cardiovascular disease, while femur bone mineral density had a non-linear relationship with cardiovascular disease, with an inflection point of 0.741 gm/cm². When bone mineral density was <0.741 gm/cm², the risk of cardiovascular disease decreased speedily. Once bone mineral density exceeded this value, the risk of cardiovascular disease continued to decrease, but the trend became significantly slower. Compared with patients with normal bone mass, osteoporosis was associated with a 2.05-fold increased risk of cardiovascular disease (95% CI 1.68-5.52). There were no significant differences in interaction tests of all subgroups (p for interaction >0.05) except race.

Conclusion

Our results indicated that bone mineral density was closely associated with the prevalence of cardiovascular disease in older adults over 60 years old, especially the femur bone mineral density was negatively non-linear associated with cardiovascular disease risk, with an inflection point of 0.741 gm/cm².

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.

The association between weight-adjusted-waist index and total bone mineral density in adolescents: NHANES 2011-2018

Introduction

The weight-adjusted waist index (WWI) serves as an innovative obesity measure, seemingly surpassing body mass index (BMI) and waist circumference (WC) in evaluating lean and fat mass. This study aimed to explore the relationship between WWI and total bone mineral density (BMD) in US adolescents.

Methods

This population-based study investigated adolescents aged 8-19 years with comprehensive WWI and total BMD data from the National Health and Nutrition Examination Survey (NHANES) 2011-2018. WWI was computed by dividing WC by the square root of body weight. Weighted multivariate linear regression and smoothed curve fitting were employed to examine linear and non-linear associations. Threshold effects were determined using a two-part linear regression model. Additionally, subgroup analyses and interaction tests were conducted.

Results

Multivariate linear regression analysis revealed a significant negative association between WWI and total BMD in 6,923 US adolescents aged 8-19 years [β = -0.03, 95% CI: (-0.03, -0.03)]. This negative correlation remained consistent across all subcategories, with the exception of age, encompassing gender,ethnicity, and diabetes status subgroups. Furthermore, a non-linear relationship and saturation effect between WWI and total BMD were identified, with an inflection point at 9.88 cm/√kg.

Conclusions

Our research demonstrated a notable negative relationship and saturation effect between WWI and total BMD among US adolescents.

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.

Dietary fiber intake associated with risk of rheumatoid arthritis among U.S. adults: NHANES 2010-2020

Rheumatoid arthritis (RA) is a prevalent inflammatory joint disease that imposes a significant medical burden and morbidity. Recent scientific evidence suggests that dietary components and patterns could be associated with RA risk. In this study, we aim to investigate the possible relationship between dietary fiber intake and RA risk. We included 15,114 participants from the 2010 to 2020 National Health and Nutrition Examination Survey database in our study. Participants aged 20 or above were categorized into those with and without RA. Univariate logistic regression analysis and multivariate regression models were used to test the association between dietary fiber intake, high-sensitivity C-reactive protein, and RA. Out of all the participants, 1053 were diagnosed with RA (6.97%). Multivariate logistic regression analysis indicated that fiber intake was negatively associated with high-sensitivity c-reactive protein (-0.09 [-0.18, -0.02]) and RA risk (0.99 [0.98, 0.99]). Furthermore, our sensitivity analysis suggested that individuals with higher fiber intake (>19.1 g/day) had a 25% lower risk of developing RA than those with lower fiber intake [0.75 (0.63, 0.88)]. Our findings suggest that higher dietary fiber intake is associated with a reduced risk of RA and may help reduce systemic inflammation, thereby potentially slowing down RA progression.

The association between oxidative balance score and periodontitis in adults: a population-based study

Introduction

The pathogenesis between oxidative stress and periodontitis was correlated. The Oxidative Balance Score (OBS) is a systematic tool to assess the effects of diet and lifestyle in relation to oxidative stress. However, the association between OBS and periodontitis has not been reported previously.

Methods

Sixteen dietary factors and four lifestyle factors were selected to score the OBS. Multivariate logistic regression and sensitivity analysis were used to investigate the relationship between OBS and periodontitis based on data from the National Health and Nutrition Examination Survey (NHANES) 1999-2018. Subgroup analysis and interaction tests were used to investigate whether this association was stable across populations.

Results

This study included 3,706 participants. There was a negative linear association between OBS and periodontitis in all participants [0.89 (0.80, 0.97)], and after converting OBS to a quartile variable, participants with OBS in the highest quartile had a 29% lower risk of periodontitis than those with OBS in the lowest quartile [0.71 (0.42, 0.98)]. This negative association differed with respect to age and diabetes.

Conclusion

There is a negative association between OBS and periodontitis in US adults. Our results suggest that OBS may be used as a biomarker for measuring periodontitis.

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.