Serum albumin mediates the associations between heavy metals and two novel systemic inflammation indexes among U.S. adults

Associations of Serum Manganese, Zinc, Copper, and Selenium Concentrations With Autism Spectrum Disorders in Chinese Children: A Case-Control Study

Imbalances in several trace elements related to antioxidant function may lead to autism spectrum disorder (ASD)-related physiological dysfunction. Nonetheless, contradictory results have been found on the connection between these elements and ASD, and studies of their joint effects and interactions have been insufficient. We therefore designed a case-control study of 152 ASD children and 152 age- and sex-matched typically developing (TD) children to explore the individual and combined associations of manganese (Mn), zinc (Zn), copper (Cu), and selenium (Se) with ASD. Compared with TD, ASD has lower Zn and Se levels and higher Cu levels. The restricted cubic spline model showed J-shaped non-linearity, L-shaped non-linearity, and positive linearity correlations between Mn, Zn, Cu, and ASD. Zn and Cu were negatively and positively correlated with ASD symptoms, respectively. The superoxide dismutase (SOD) mediated 50.53% and 39.07% of the association between Zn, Se, and ASD, respectively. Bayesian kernel machine regression (BKMR) confirmed a U-shaped correlation between the element mixtures and ASD. Interactions of Mn with the other three elements and Cu with Zn were also observed. Our results confirm that the independent and combined exposure to the four trace elements was associated with ASD, with oxidative stress being an important mechanism. Due to the potential interactions between the elements, further research is needed to explore their involvement in the pathogenesis and progression of ASD from a combined perspective, as well as the beneficial and harmful concentration ranges.

Association between blood heavy metals and fecal incontinence in American adults: A population-based study

BACKGROUND

Previous studies have revealed the impact of heavy metals (HMs) on gut microbiota and intestinal structure. However, the relationship between HMs and fecal incontinence (FI) remains unclear. Therefore, this study aims to evaluate the association between blood HMs exposure and FI.

METHODS

Data for this study were obtained from the 2005-2010 cycles of National Health and Nutrition Examination Survey (NHANES). Information regarding FI was retrieved from the Bowel Health Questionnaire, while data on HMs were collected through laboratory examinations. Weighted logistic regression, two-indices weighted quantile sum (2iWQS), quantile g-computation (qgcomp), and restricted cubic splines (RCS) were employed to explore the relationships between blood levels of cadmium (Cd), lead (Pb), and mercury (Hg) and FI. Additionally, Subgroup analyses were conducted to discern specific associations within distinct populations.

RESULTS

A total of 12,142 participants aged 20 years and above were included in this study. Weighted logistic regression indicated a positive association between Cd (Crude model: OR = 1.21, 95% CI: 1.09-1.35, p < 0.001) and Pb (Crude model: OR = 1.01, 95% CI: 1.01-1.02, p < 0.001) with FI. After adjusting for all covariates, the positive associations remained significant for Cd (Model 2: Q1 vs. Q3, OR = 1.38, 95% CI: 1.04-1.83, p = 0.026) and Pb (Model 2: OR = 1.01, 95% CI: 1.00-1.01, p = 0.004). The 2iWQS regression analysis demonstrated a positive correlation between the mixture of three blood HMs and FI (OR = 1.18, 95% CI: 1.05-1.32, p = 0.005), with Cd having the highest weight among the metals (0.76). The qgcomp analysis confirmed this finding (OR = 1.12, 95% CI: 1.01-1.26, p = 0.036; weight = 0.72). Subgroup analysis revealed that the positive association between Cd and FI was more pronounced among males; Mexican Americans; those with a poverty income ratio (PIR) > 2; individuals with college or above education; overweight participants; never-smokers; heavy drinkers; those with hypertension; and non-diabetes individuals. Conversely, the association between Pb and FI was stronger among participants aged 40-60, overweight participants, and never-smokers.

CONCLUSION

Exposure to blood HMs, particularly Cd, is associated with FI in American adults. Future research should focus on elucidating the causal relationships and underlying mechanisms.

Association between neutrophil-percentage-to-albumin ratio (NPAR) and metabolic syndrome risk: insights from a large US population-based study

Metabolic syndrome (MetS) is a cluster of conditions that increase the risk of cardiovascular disease and diabetes. This study aimed to investigate the association between Neutrophil-Percentage-to-Albumin Ratio (NPAR) and MetS in a large, nationally representative US population. We analyzed data from 28,178 participants in the National Health and Nutrition Examination Survey (NHANES) 2005-2018. Logistic regression models were used to evaluate the association between NPAR and MetS. Restricted cubic spline (RCS) models were employed to assess the dose-response relationship. Mediation analyses were conducted to explore potential mediating effects of serum uric acid and triglyceride-glucose (TyG) index. After adjusting for confounders, participants in the highest NPAR quartile had a 14% higher risk of MetS compared to those in the lowest quartile (OR 1.14, 95%CI 1.03-1.27, P = 0.010). RCS models revealed a monotonic increasing trend between NPAR and MetS risk (P for overall association = 0.002). Mediation analyses showed that serum uric acid and TyG index mediated 14.93% and 29.45% of the total effect of NPAR on MetS, respectively. Subgroup analyses indicated that the positive association between NPAR and MetS was more pronounced in Mexican Americans, individuals aged 20-65 years, those with lower income, males, current smokers, and moderate drinkers. Higher NPAR is associated with increased risk of MetS in the US adult population. This association is partially mediated by serum uric acid and TyG index. These findings suggest that NPAR may serve as a novel biomarker for MetS risk assessment and provide insights into potential mechanisms linking inflammation and metabolic disorders.

Association of Long-Term Exposure to PM2.5 Constituents and Green Space With Arthritis and Rheumatoid Arthritis

There is limited evidence regarding the effects of long-term exposure to PM2.5 constituents on the risk of arthritis and rheumatoid arthritis, and the interaction between PM2.5 and green space remains unclear. This study examined the relationship between long-term exposure to PM2.5 constituents and the risk of arthritis and rheumatoid arthritis, with the exposure period extending from recruitment until self-reported outcomes, death, loss to follow-up, or end of follow-up. Additionally, the study assessed whether there was an interactive effect between PM2.5 and green space on these risks. We gathered cohort data on 18,649 individuals aged ≥45 years. We applied generalized linear mixed-effects models to estimate the effects of PM2.5 constituents, NDVI, and their interaction on arthritis and rheumatoid arthritis. The quantile g-computation and weighted quantile sum regression model were applied to estimate the combined effect of PM2.5 constituents. Our results showed that exposure to single and mixed PM2.5 constituents adversely affected arthritis and rheumatoid arthritis, and was mainly attributed to the black carbon component. We observed "U" or "J" shaped exposure-response curves for the effects of PM2.5, OM, NO3 - and NH4 + exposure on the development of arthritis/rheumatoid arthritis. Additionally, the odds ratio of arthritis for per interquartile range (IQR) increase in PM2.5 was 1.209 (95% CI:1.198, 1.221), per 0.1-unit decrease in NDVI was 1.091 (95% CI:1.033, 1.151), and the interaction term was 1.005 (95% CI:1.002, 1.007). These findings flesh out the existing evidence for PM2.5 constituents, NDVI and arthritis, rheumatoid arthritis, but the underlying mechanisms still require further exploration.

Serum albumin and liver dysfunction mediate the associations between organophosphorus pesticide exposure and hypertension among US adults

BACKGROUND

Human health is commonly threatened by organophosphorus pesticides (OPPs) due to their widespread use and biological characteristics. However, the combined effect of mixtures of OPPs metabolites on the risk of hypertension and potential mechanism remain limited.

OBJECTIVES

To comprehensively investigate the effects between OPPs exposure on hypertension risk and explore and underlying mechanism among US general population.

METHODS

This cross-sectional study collected US adults who had available data on urine OPPs metabolites (dialkyl phosphate compounds, DAPs) from the National Health and Nutrition Examination Survey (NHANES) to assess the relationships of DAPs with hypertension risk. Survey-weighted logistic regression, restricted cubic spline (RCS), and mixed exposure analysis models [weighted quantile sum regression (WQS) and Bayesian kernel machine regression (BKMR)] were used to analyze individual, dose-response and combined associations between urinary DAPs metabolites and hypertension risk, respectively. Mediation analysis determined the potential intermediary role of serum albumin and liver function in the above associations.

RESULTS

Compared with the reference group, participants with the highest tertile levels of DEP, DMTP, DETP, and DMDTP experienced increased risk of hypertension by 1.21-fold (95%CI: 1.02-1.36), 1.20-fold (95%CI: 1.02-1.42), 1.19-fold (95%CI: 1.01-1.40), and 1.17-fold (95%CI: 1.03-1.43), respectively. RCS curve also showed positive exposure-response associations of individual DAPs with hypertension risk. WQS and BKMR analysis further confirmed DAP mixtures were significantly associated with increased risk of hypertension, with DEP identified as a major contributor to the combined effect. Mediation analysis indicated that serum albumin and AST/ALT ratios played crucial mediating roles in the relationships between individual and mixed urinary DAPs and the prevalence of hypertension.

CONCLUSION

Our findings provided more comprehensive and novel perspectives into the individual and combined effects of urinary OPPs matabolites on the increased risk of hypertension and the possible driving mechanism, which would be of great significance for environmental control and early prevention of hypertension.

Inflammation and olfactory loss are associated with at least 139 medical conditions

Olfactory loss accompanies at least 139 neurological, somatic, and congenital/hereditary conditions. This observation leads to the question of whether these associations are correlations or whether they are ever causal. Temporal precedence and prospective predictive power suggest that olfactory loss is causally implicated in many medical conditions. The causal relationship between olfaction with memory dysfunction deserves particular attention because this sensory system has the only direct projection to memory centers. Mechanisms that may underlie the connections between medical conditions and olfactory loss include inflammation as well as neuroanatomical and environmental factors, and all 139 of the medical conditions listed here are also associated with inflammation. Olfactory enrichment shows efficacy for both prevention and treatment, potentially mediated by decreasing inflammation.

Independent and joint associations of multiple metals exposure with vital capacity index: a cross-sectional study in Chinese children and adolescents

OBJECTIVE

The current study aimed to explore the relationships between urinary metals and vital capacity index (VCI) in 380 children and adolescents in Northeast China using a variety of statistical methods.

METHODS

A cross-sectional survey was conducted among 380 children and adolescents in Liaoning Province, China. To assess the relationships between urinary metals and VCI, Elastic-net (ENET) regression, multivariate linear regression, weighted quantile sum (WQS), bayesian kernel machine regression (BKMR) and quantile-based g computation (qgcomp) were adopted.

RESULTS

The ENET model selected magnesium (Mg), vanadium (V), manganese (Mn), arsenic (As), tin (Sn) and lead (Pb) as crucial elements. In multiple linear regression, we observed urinary Pb, Mn was negatively correlated with VCI individually in both total study population and adolescents (all p values < 0.05) in the adjustment model. The WQS indices were negatively related with VCI in total study population (β=-3.19, 95%CI: -6.07, -0.30) and adolescents (β=-3.46, 95%CI: -6.58, -0.35). The highest weight in total study population was Pb (38.80%), in adolescents was Mn (35.10%). In the qgcomp, Pb (31.90%), Mn (27.20%) were the major negative contributors to the association in the total population (β=-3.51, 95%CI: -6.29, -0.74). As (42.50%), Mn (39.90%) were the main negative contributors (β=-3.95, 95% CI: -6.68, -1.22) among adolescents. The results of BKMR were basically consistent with WQS and qgcomp analyses.

CONCLUSIONS

Our results indicated that Pb and Mn were priority toxic materials on VCI. The cumulative effect of metals was negatively related to VCI, and this relationship was more pronounced in adolescents.

Association between heavy metals exposure and persistent infections: the mediating role of immune function

Introduction

Persistent infections caused by certain viruses and parasites have been associated with multiple diseases and substantial mortality. Heavy metals are ubiquitous environmental pollutants with immunosuppressive properties. This study aimed to determine whether heavy metals exposure suppress the immune system, thereby increasing the susceptibility to persistent infections.

Methods

Using data from NHANES 1999-2016, we explored the associations between heavy metals exposure and persistent infections: Cytomegalovirus (CMV), Epstein-Barr Virus (EBV), Hepatitis C Virus (HCV), Herpes Simplex Virus Type-1 (HSV-1), Toxoplasma gondii (T. gondii), and Toxocara canis and Toxocara cati (Toxocara spp.) by performing logistic regression, weighted quantile sum (WQS) and Bayesian kernel machine regression (BKMR) models. Mediation analysis was used to determine the mediating role of host immune function in these associations.

Results

Logistic regression analysis revealed positive associations between multiple heavy metals and the increased risk of persistent infections. In WQS models, the heavy metals mixture was associated with increased risks of several persistent infections: CMV (OR: 1.58; 95% CI: 1.17, 2.14), HCV (OR: 2.94; 95% CI: 1.68, 5.16), HSV-1 (OR: 1.25; 95% CI: 1.11, 1.42), T. gondii (OR: 1.97; 95% CI: 1.41, 2.76), and Toxocara spp. (OR: 1.76; 95% CI: 1.16, 2.66). BKMR models further confirmed the combined effects of heavy metals mixture and also identified the individual effect of arsenic, cadmium, and lead. On mediation analysis, the systemic immune inflammation index, which reflects the host's immune status, mediated 12.14% of the association of mixed heavy metals exposure with HSV-1 infection.

Discussion

The findings of this study revealed that heavy metals exposure may increase susceptibility to persistent infections, with the host's immune status potentially mediating this relationship. Reducing exposure to heavy metals may have preventive implications for persistent infections, and further prospective studies are needed to confirm these findings.

Association of Metal Exposure with Novel Immunoinflammatory Indicators

Objective: We aimed to investigate the relationship between metal exposure and novel immunoinflammatory indicators. Methods: Data on adults participating in the National Health and Nutrition Examination Survey (NHANES) from 2009 to 2018 were analyzed. Various statistical models were employed to assess the association between metal exposure and novel immune-inflammation-related indicators. Additionally, the impact of metal exposure on inflammation in different gender populations was explored. Results: This study included 4482 participants, of whom 51.1% were male. Significant correlations were observed among various metals. Both elastic net (ENET) and linear regression models revealed robust associations between cadmium (Cd), cobalt (Co), arsenic (As), mercury (Hg), and immunoinflammatory indicators. Weighted quantile sum (WQS) and Quantile g-computation (Q-gcomp) models demonstrated strong associations between barium (Ba), Co, and Hg and immunoinflammatory indicators. Bayesian kernel machine regression (BKMR) analysis indicated an overall positive correlation between in vivo urinary metal levels and systemic inflammation response index (SIRI) and aggregate index of systemic inflammation (AISI). Furthermore, Co, As, and Hg emerged as key metals contributing to changes in novel immunoinflammatory indicators. Conclusions: Metals exhibit associations with emerging immunoinflammatory indicators, and concurrent exposure to mixed metals may exacerbate the inflammatory response. Furthermore, this relationship varies across gender populations.

Association of two novel systemic inflammatory biomarkers and frailty based on NHANES 2007-2018

Background

Frailty is a significant concern in the field of public health. However, currently, there is a lack of widely recognized and reliable biological markers for frailty. This study aims to investigate the association between systemic inflammatory biomarkers and frailty in the older adult population in the United States.

Methods

This study employed data from the National Health and Nutrition Examination Survey (NHANES) spanning 2007 to 2018 and conducted a rigorous cross-sectional analysis. We constructed weighted logistic regression models to explore the correlation between the Systemic Immune-Inflammation Index (SII), Systemic Inflammatory Response Index (SIRI), and frailty in the population aged 40 to 80 years. Using restricted cubic spline (RCS), we successfully visualized the relationship between SII, SIRI, and frailty. Finally, we presented stratified analyses and interaction tests of covariates in a forest plot.

Results

This study involved 11,234 participants, 45.95% male and 54.05% female, with an average age of 64.75 ± 0.13 years. After adjusting for relevant covariates, the weighted logistic regression model indicated an odds ratio (OR) and 95% confidence interval(CI) for the correlation between frailty and the natural logarithm (ln) transformed lnSII and lnSIRI as 1.38 (1.24-1.54) and 1.69 (1.53-1.88), respectively. Subsequently, we assessed different levels of lnSII and lnSIRI, finding consistent results. In the lnSII group model, the likelihood of frailty significantly increased in the fourth quartile (OR = 1.82, 95% CI: 1.55-2.12) compared to the second quartile. In the lnSIRI group model, the likelihood of frailty significantly increased in the third quartile (OR = 1.30, 95% CI: 1.10-1.53) and fourth quartile (OR = 2.29, 95% CI: 1.95-2.70) compared to the second quartile. The interaction results indicate that age and income-to-poverty ratio influence the association between lnSIRI and frailty. RCS demonstrated a nonlinear relationship between lnSII, lnSIRI, and frailty.

Conclusion

The results of this cross-sectional study indicate a positive correlation between systemic inflammatory biomarkers (SII, SIRI) and frailty.

Combined exposure to multiple metals on abdominal aortic calcification: results from the NHANES study

Exposure to metals increases the risk of many diseases and has become a public health concern. However, few studies have focused on the effect of metal on abdominal aortic calcification (AAC), especially the combined effects of metal mixtures. In this study, we aim to investigate the combined effect of metals on AAC risk and determine the key components in the multiple metals. We tried to investigate the relationship between multiple metal exposure and AAC risk. Fourteen urinary metals were analyzed with five statistical models as follows: generalized linear regression, weighted quantile sum regression (WQS), quantile g-computation (Qgcomp), and Bayesian kernel machine regression (BKMR) models. A total of 838 participants were involved, of whom 241 (28.8%) had AAC. After adjusting for covariates, in multiple metal exposure logistic regression, cadmium (Cd) (OR = 1.364, 95% CI = 1.035-1.797) was positively associated with AAC risk, while cobalt (Co) (OR = 0.631, 95% CI = 0.438-0.908) was negatively associated with AAC risk. A significant positive effect between multiple metal exposure and AAC risk was observed in WQS (OR = 2.090; 95% CI = 1.280-3.420, P < 0.01), Qgcomp (OR = 1.522, 95% CI = 1.012-2.290, P < 0.05), and BKMR models. It was found that the positive association may be driven primarily by Cd, lead (Pb), uranium (U), and tungsten (W). Subgroups analysis showed the association was more significant in participants with BMI ≥ 25 kg/m2, abdominal obesity, drinking, and smoking. Our study shows that exposure to multiple metals increases the risk of AAC in adults aged ≥ 40 years in the USA and that Cd, Pb, U, and W are the main contributors. The association is stronger in participants who are obese, smoker, or drinker.