樱花视频

Skip to main content
  • Research
  • Published:

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

Abstract

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鈥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鈥=鈥1.21, 95% CI: 1.09鈥1.35, p鈥<鈥0.001) and Pb (Crude model: OR鈥=鈥1.01, 95% CI: 1.01鈥1.02, p鈥<鈥0.001) with FI. After adjusting for all covariates, the positive associations remained significant for Cd (Model 2: Q1 vs. Q3, OR鈥=鈥1.38, 95% CI: 1.04鈥1.83, p鈥=鈥0.026) and Pb (Model 2: OR鈥=鈥1.01, 95% CI: 1.00鈥1.01, p鈥=鈥0.004). The 2iWQS regression analysis demonstrated a positive correlation between the mixture of three blood HMs and FI (OR鈥=鈥1.18, 95% CI: 1.05鈥1.32, p鈥=鈥0.005), with Cd having the highest weight among the metals (0.76). The qgcomp analysis confirmed this finding (OR鈥=鈥1.12, 95% CI: 1.01鈥1.26, p鈥=鈥0.036; weight鈥=鈥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)鈥>鈥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鈥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.

Peer Review reports

Introduction

In recent years, the health issues caused by heavy metals (HMs) exposure have garnered widespread attention. Ubiquitous in daily life, HMs are found in soil, air, dust, drinking water, food, and industrial products [1, 2]. However, existing studies have demonstrated that long-term bioaccumulation of HMs can inflict damage on various tissues and organs and may even lead to increased mortality rates [3]. For instance, exposure to cadmium (Cd) is primarily linked to the increased risk of cardiovascular diseases, renal damage, and osteoporosis [4,5,6]. Lead (Pb) and mercury (Hg), due to their neurotoxicity, are associated with central nervous system disorders, such as cognitive decline [7,8,9,10]. Furthermore, emerging research underscores the significant health impacts of co-exposure to multiple HMs, with associations to conditions such as hypertension, diabetes, metabolic syndrome, dyslipidemia, as well as liver damage, pulmonary harm, and psoriasis [11,12,13,14,15,16]. Therefore, it is crucial to identify which organs or systems are adversely affected by HMs.

Diet is a significant source of HMs [17]. Research indicates that over 90% of non-occupational Cd exposure in the general population (excluding smokers) comes from the consumption of grains, vegetables, and other plant-based foods [18]. According to a study by the Centers for Disease Control and Prevention (CDC), Hg exposure in young children and childbearing-aged women primarily arises from the consumption of seafood, including freshwater fish, marine fish, and shellfish [19]. Given that the digestive tract is the primary site for food digestion and absorption, exposure to HMs can cause substantial damage to the gastrointestinal system, including a reduced abundance and diversity of gut microbiota and alterations in intestinal structure [20]. Despite these concerns, there is limited research investigating the relationship between HMs and gastrointestinal diseases.

Fecal incontinence (FI) is a prevalent gastrointestinal disorder characterized by the involuntary leakage of solid or liquid feces [21]. The global prevalence of FI is approximately 8%, with higher rates observed among the elderly and females [22]. FI not only significantly impacts quality of life but is also associated with various conditions, including gastrointestinal cancers, lymphomas, depression, and sarcopenia [23,24,25,26]. The etiologies of FI encompass neurological degenerative diseases, muscle damage, and gastrointestinal disorders [27]. Given the neurotoxic effects of HMs and their impact on the gastrointestinal tract, a potential link between HMs and FI may exist; however, supporting evidence remains limited.

Therefore, this study aims to investigate the associations between blood Cd, Pb, Hg, as well as their mixture and FI using data from 12,142 participants in NHANES 2005鈥2010. To evaluate these relationships, we employed weighted logistic regression, two-indices weighted quantile sum (2iWQS), quantile g-computation (qgcomp), and restricted cubic spline (RCS) analyses.

Methods

Study design and population

The National Health and Nutrition Examination Survey (NHANES), conducted by the National Center for Health Statistics (NCHS) under the CDC, is a large-scale survey designed to assess the health and nutritional status of U.S. adults and children. The survey employs a multistage probability sampling method, drawing representative samples from various counties across the United States every two years for health and nutrition assessments. All NHANES projects receive approval from the NCHS Research Ethics Review Board, and participants provide written consent upon enrollment (NHANES鈥擭CHS Research Ethics Review Board Approval (cdc.gov)).

In this study, data were retrieved from the NHANES cycles of 2005鈥2006, 2007鈥2008, and 2009鈥2010. We excluded participants who were under the age of 20 (N鈥=鈥13,902), had missing FI data (N鈥=鈥2,415), missing blood HMs data (N鈥=鈥550), missing covariate data (N鈥=鈥1,529), or had used laxatives in the past 30 days (N鈥=鈥496). A total of 12,142 participants were ultimately included in the final analysis (Fig.听1).

Fig.听1
figure 1

Flowchart of participant selection

Definition of FI

In the NHANES 2005鈥2010 questionnaire section, the Bowel Health Questionnaire (BHQ) offered detailed information on FI and bowel function for adults aged 20 or older. In the Mobile Examination Center (MEC), participants were asked about the involuntary leakage of feces, including solids, liquids, mucus, or gas, and the frequency of these occurrences over the past 30 days. Additionally, the Bristol Stool Form Scale (BSFS) cards were used to assess stool morphology. Consistent with previous studies [28, 29], FI in this study was defined as the involuntary discharge of solid, mucus, or liquid stools at least once in the past month, excluding gas.

Measurement of blood HMs

Considering that the NHANES 2005鈥2010 dataset includes data only on three blood HMs (Cd, Pb, and Hg), this study focuses exclusively on their relationship with FI, excluding manganese (Mn) and selenium (Se), which were introduced in later survey cycles. Within the MECs, trained personnel collected blood samples directly from participants, which were then stored at 鈭30鈩 and sent to the National Center for Environmental Health and the CDC for subsequent analysis. Blood concentrations of Cd, Pb, and total Hg were measured using inductively coupled plasma mass spectrometry (ICP-MS). Detailed experimental procedures and methods are outlined in the NHANES laboratory protocol. According to the NHANES analysis guidelines, measurements below the limit of detection (LOD) were substituted with LOD divided by the square root of 2 (\(\sqrt{2}\)) [30]. Additionally, the concentrations of the three blood HMs in this study are expressed in 渭g/L. The specific LOD values for the three metals, as well as the proportions of values below the detection limit, can be found in Table S1 and Table S2.

Covariates

Based on previous research [31,32,33], we included several potentially significant variables that could affect FI as confounders, such as demographic characteristics (age, sex, race, education level, family poverty income ratio [PIR]); body mass index (BMI); lifestyle behaviors (smoking status, alcohol consumption); and chronic conditions (hypertension, diabetes). A directed acyclic graph was created, as shown in Figure S1.

Race was categorized as non-Hispanic Black, non-Hispanic White, Mexican American, and other races (including other Hispanics and multiple races). Education level was classified as less than high school, high school, and college or above. BMI was categorized as: normal (<鈥25 kg/m2), overweight (25鈥29.9 kg/m2), and obese (鈮モ30 kg/m2). The continuous variable PIR was dichotomized into a binary variable (PIR鈥<鈥2, PIR鈥夆墺鈥2). Smoking status was defined as: never (having smoked fewer than 100 cigarettes in a lifetime), former (having smoked more than 100 cigarettes in a lifetime but not currently smoking), and now (having smoked more than 100 cigarettes in a lifetime and currently smoking). Alcohol consumption was categorized as: never (fewer than 12 alcoholic drinks in a lifetime); former (12 or more alcoholic drinks in a lifetime but none in the past 2 years); mild (women consuming more than 1 drink per day, men more than 2 drinks per day); moderate (women 2 drinks per day, men 3 drinks per day); and heavy (women 3 or more drinks per day, men 4 or more drinks per day). Hypertension was defined as: [1] a doctor鈥檚 diagnosis of hypertension; [2] use of antihypertensive medication; or [3] systolic blood pressure greater than 140 mmHg or diastolic blood pressure greater than 90 mmHg. Diabetes was defined as: [1] a doctor鈥檚 diagnosis of diabetes; [2] glycated hemoglobin鈥夆墺鈥6.5%; [3] fasting blood glucose鈥夆墺鈥7.0 mmol/L, random blood glucose鈥夆墺鈥11.1 mmol/L, or 2-h OGTT blood glucose鈥夆墺鈥11.1 mmol/L; or [4] use of antidiabetic medication or insulin.

Statistical analysis

Continuous variables were presented as weighted means (卤鈥塻tandard errors), while categorical variables were shown as unweighted counts (weighted percentages). Comparisons between continuous variables were performed using t-tests, whereas comparisons between categorical variables were conducted using chi-square tests. The associations among the three blood HMs were assessed using Pearson correlation analysis.

First, weighted logistic regression analysis was used to assess the relationship between each HM and FI. Three models were constructed to adjust for confounding variables: the crude model, unadjusted; Model 1, adjusted for age, sex, race, education level, and PIR; and Model 2, further adjusted for BMI, smoking status, alcohol consumption, hypertension, and diabetes. Subsequently, we performed a test for linear trends by inputting the median value of each metal as a continuous variable into the model.

Second, given that traditional WQS regression models may be limited by the directional effects of mixtures on outcomes, and that mixtures may contain both 鈥済ood鈥 and 鈥渂ad鈥 components [34], we employed the two-indices WQS (2iWQS) regression model to separately assess the positive and negative effects of HMs [35]. Specifically, data were randomly divided into training and validation sets with a 4:6 ratio. We performed 200 iterations in the training set to obtain weights for each HM and tested their significance in the validation set. The 2iWQS index comprises 鈥淧WQS鈥 and 鈥淣WQS,鈥 which represent the positive and negative effects, respectively. Additionally, to further validate the robustness of the results, quantile g-computation (qgcomp) analysis was conducted to explore the association between HMs and FI.

Restricted Cubic Splines (RCS) were used to assess the nonlinear relationship between HMs and FI. To avoid underfitting or overfitting and ensure model accuracy, the optimal number of knots for RCS was selected based on the minimum Akaike Information Criterion (AIC). Ultimately, the RCS curve was fitted with 4 knots. Finally, subgroup analyses were conducted to explore the relationship between HMs and FI based on age, sex, race, education level, PIR, BMI, smoking status, alcohol consumption, hypertension, and diabetes.

All analyses in this study were conducted using R software (version 4.3.2). Weighted logistic regression, 2iWQS, qgcomp, and RCS analyses were performed using the 鈥渟urvey,鈥 鈥済WQS,鈥 鈥渜gcomp,鈥 and 鈥渞ms鈥 packages, respectively. A p-value of less than 0.05 was considered statistically significant.

Results

Baseline characteristics

A total of 12,142 participants were included in this study, with a mean age of 46.6 years (卤鈥0.3). Among them, 40.4% were aged between 40 and 59 years, 50.2% were female, and the majority were non-Hispanic white (72.6%). FI was observed in 1,074 participants, accounting for 8.8% of the sample. The blood levels of HMs were 0.52 (卤鈥0.01) 渭g/L for Cd, 16.53 (卤鈥0.27) 渭g/L for Pb, and 1.65 (卤鈥0.05) 渭g/L for Hg, with no significant correlations among them (r鈥<鈥0.2) (Figure S2). Compared to the non-FI individuals, FI was more common among older individuals, females, non-Hispanic Whites, those with lower PIR, obesity, smokers, heavy drinkers, and those with hypertension or diabetes. Additionally, FI participants had higher blood levels of Cd (0.60 vs 0.51, p鈥<鈥0.001) and Pb (19.27 vs 16.28, p鈥<鈥0.001) compared to those without FI. However, FI participants had lower blood levels of Hg, though this difference was not statistically significant (Table听1).

Table 1 Baseline characteristics of normal and FI participants in NHANES 2005鈥2010

Multiple logistic analysis

Logistic regression analysis showed a significant positive association between blood Cd levels and FI when Cd was analyzed as a continuous variable (Crude model: OR鈥=鈥1.21, 95% CI: 1.09鈥1.35, p鈥<鈥0.001; Model 1: OR鈥=鈥1.14, 95% CI: 1.01鈥1.28, p鈥<鈥0.001). However, after adjusting for all covariates, this association was no longer significant (Model 2: OR鈥=鈥1.10, 95% CI鈥=鈥0.96鈥1.27, p鈥=鈥0.156). When Cd was categorized into tertiles, the highest tertile (Q3) showed a significant positive association with FI compared to the lowest tertile (Q1) (Crude model: Q3 vs. Q1, OR鈥=鈥1.83, 95% CI: 1.47鈥2.28, p鈥<鈥0.001, p for trend鈥<鈥0.001; Model 1: OR鈥=鈥1.38, 95% CI: 1.09鈥1.73, p鈥=鈥0.008, p for trend鈥=鈥0.008). This relationship remained robust after adjusting for all confounders (Model 2: Q3 vs. Q1, OR鈥=鈥1.38, 95% CI鈥=鈥1.04鈥1.83, p鈥=鈥0.026, p for trend鈥=鈥0.026) (Table听2).

Table 2 Multiple logistic analysis between blood heavy metals and FI

Similarly, when blood Pb was analyzed as a continuous variable, logistic regression analysis revealed a significant positive association between blood Pb levels and FI, with this relationship maintaining statistical significance across all three models (Crude model: OR鈥=鈥1.01, 95% CI: 1.01鈥1.02, p鈥<鈥0.001; Model 1: OR鈥=鈥1.01, 95% CI: 1.00鈥1.01, p鈥=鈥0.007; Model 2: OR鈥=鈥1.01, 95% CI: 1.01鈥1.01, p鈥=鈥0.004). However, when Pb was considered as a categorical variable, a significant positive association between Pb and FI was observed only in the unadjusted model (Crude model: Q2 vs Q1, OR鈥=鈥1.58, 95% CI: 1.28鈥1.94, p鈥<鈥0.001; Q3 vs Q1, OR鈥=鈥1.88, 95% CI: 1.53鈥2.30, p鈥<鈥0.001). This statistical significance not observed after adjusting for confounders.

Regarding blood Hg, logistic regression analysis showed no significant association between blood Hg levels and FI, whether Hg was considered as a continuous or categorical variable (all p-惫补濒耻别蝉鈥&驳迟;鈥0.05).

2iWQS and qgcomp model

As shown in Table听3, the 2iWQS regression analysis indicated a positive association between combined exposure to the three blood HMs and FI (OR鈥=鈥1.18, 95% CI: 1.05鈥1.32, p鈥=鈥0.005), with no negative association observed. The qgcomp analysis corroborated this finding (OR鈥=鈥1.12, 95% CI: 1.01鈥1.26, p鈥=鈥0.036). The estimated weights for individual HMs in the WQS analysis are shown in Fig.听2. Among the three HMs, Cd had the highest positive weight (0.76), while Hg had the highest negative weight (0.76); however, no significant negative association was observed. Similarly, the qgcomp analysis confirmed these findings, demonstrating the robustness of the findings (Figure S3).

Table 3 Result of the 2iWQS and qgcomp models
Fig.听2
figure 2

WQS model regression index weights for blood heavy metals exposure on fecal incontinence

RCS

The RCS curves demonstrated a significant nonlinear association between Cd and FI after adjusting for all covariates (p-辞惫别谤补濒濒鈥=鈥0.019, p-nonlinear鈥=鈥0.028) (Fig.听3A). In contrast, a linear positive correlation was observed between Pb and FI (p-辞惫别谤补濒濒鈥=鈥0.008, p-nonlinear鈥=鈥0.492) (Fig.听3B). No significant relationship was found between Hg and FI (Fig.听3C).

Fig.听3
figure 3

RCS curves between blood Cd(A), Pb(B), Hg(C) and fecal incontinence. ALL were adjusted for age, gender, race, PIR, education level, BMI, smoking status, alcohol consumption, hypertension and diabetes

Subgroup analyses

As shown in Fig.听4, the subgroup analysis revealed that the positive correlation between Cd and FI was more pronounced among males, Mexican Americans, those with PIR鈥>鈥2, individuals with college or above education, overweight participants, never-smokers, heavy drinkers, those with hypertension, and non-diabetic individuals. The positive association between Pb and FI was stronger among participants aged 40鈥60, overweight participants, and never-smokers. No specific subgroup exhibited a significant correlation between Hg and FI.

Fig.听4
figure 4

Forest plot of subgroup analysis based on age, gender, race, PIR, education level, BMI, smoking status, alcohol consumption, hypertension and diabetes. * represents P鈥&濒迟;鈥0.05

Discussion

Utilizing a large-scale, nationally representative study, we identified a significant positive correlation between blood HMs and FI, which remains robust even after adjusting for various confounding factors. Multivariate logistic regression analysis revealed that exposure to Cd and Pb is associated with FI. Both the 2iWQS and qgcomp analyses confirmed that the positive association between three blood HMs and FI persists, with Cd emerging as the most substantial contributor. The RCS curves suggested a nonlinear positive correlation between Cd and FI and a linear positive correlation between Pb and FI. Subgroup analysis highlighted that the positive association between Cd and FI was more pronounced among males, Mexican Americans, those with a PIR鈥>鈥2, individuals with college or above education, overweight individuals, heavy drinkers, those with hypertension, and non-diabetics. The positive association between Pb and FI is more evident in the 40鈥60 age group, overweight individuals, and non-smokers. To our knowledge, this is the first study to explore the relationship between blood HMs and FI.

However, the specific mechanisms underlying the relationship between HMs and FI remain unclear. We propose that this relationship may be influenced by several factors. Firstly, exposure to HMs can alter the diversity and structure of gut microbiota. Trevors et al. demonstrated that Cd inhibited the growth of intestinal microbiota by interfering with protein synthesis and the function of various enzyme systems [36]. Zhang et al. showed that Cd disrupted the composition of gut microbiota in mice, notably reducing the abundance of Firmicutes and Proteobacteria while increasing the population of Bacteroidetes [37]. Even at low concentrations, Cd exposure has been observed to decrease both the abundance and diversity of gut microbiota [38]. Moreover, Cd exposure leads to a significant reduction in bacteria that produce short-chain fatty acids (SCFAs), impairing the function of intestinal epithelial cells, increasing intestinal permeability, and causing intestinal inflammation [39]. Similarly, Pb exposure has been found to affect the composition of gut microbiota and the integrity of the gut barrier. For instance, a recent study administering low concentrations of Pb to mice over 15 weeks found a significant increase in the abundance of Bacteroidetes and a decrease in fungi within the gut [40]. Human studies have also indicated that the 伪- and 尾-diversity of gut microbiota are influenced by urinary Pb levels [41]. Increasing evidence supports a 鈥渂idirectional relationship鈥 between HMs exposure and the gut microbiota [42], suggesting that HMs exposure can alter the metabolism of normal gut microbiota, which in turn can influence the biotransformation and toxicological effects of HMs. In summary, the impact of HMs on the gut microbiota and gut structure likely represents a significant mechanism contributing to the occurrence of FI.

Secondly, the neurotoxicity of Cd and Pb directly impacts on the central nervous system, contributing to cognitive decline [43]. A recent NHANES study found a negative correlation between blood levels of Pb and Cd and cognitive function, while blood selenium demonstrated a positive correlation with cognitive function in older adults, particularly among men [44]. Additionally, HMs have been found to positively correlate with systemic immune-inflammation index (SII) and systemic inflammation response index (SIRI). Given that inflammation is a crucial factor in the development of FI, this relationship may further elucidate the pathway by which HMs contribute to FI [45, 46].

In summary, this cross-sectional study identified a positive correlation between blood HMs and FI. This finding not only offers new insights into the detrimental effects of HMs on human health but also provides valuable reference for the prevention of FI. Reducing the intake of foods with high levels of HMs could significantly aid in preventing the onset of FI. Moreover, reducing the release of pollutants, especially waste gases and wastewater containing HMs, is essential for maintaining safe environmental levels of these metals. This is particularly important considering that a significant portion of inhaled Cd eventually enters the gastrointestinal tract [47].

Our study possesses several strengths. Firstly, it is based on a comprehensive national population dataset, providing a large sample size. Secondly, we employed multivariate logistic regression, 2iWQS, qgcomp, and RCS to adjust for multiple potential confounders, enhancing the reliability of our findings. However, there are also some limitations. Firstly, as a cross-sectional study, it cannot establish causal relationships between HMs and FI. Secondly, due to limitations in the NHANES dataset, we were unable to adjust for other potentially relevant variables associated with FI, such as congenital diseases, surgeries, and radiotherapy. Thirdly, using the NHANES-recommended method of dividing metal concentrations below the detection limit by the square root of 2 may affect the accuracy of the study results. Lastly, our study focused exclusively on the association between blood HMs and FI, leaving the relationship between dietary or urinary HMs and FI unexplored. Future research is needed to further investigate these associations.

Conclusion

Given the various health risks posed by HMs in blood and the significant prevalence of FI, understanding the connection between these factors is essential. Our study identifies an association between exposure to blood HMs, particularly cadmium (Cd), and FI. These findings provide valuable insights into the potential implications of heavy metal exposure and could inform preventive strategies for FI. However, the cross-sectional nature of this study presents limitations, emphasizing the need for future investigations to establish causal relationships and explore the underlying biological mechanisms.

Data availability

Publicly available datasets were analyzed in this study. This data can be found at: https://www.cdc.gov/nchs/nhanes/index.htm.

Abbreviations

HMs:

Heavy metals

FI:

Fecal incontinence

NHANES:

National Health and Nutrition Examination Survey

Cd:

Cadmium

Pb:

Lead

Hg:

Mercury

LOD:

Low limit of detection

2iWQS:

Two-indices weighted quantile sum

Qgcomp:

Quantile g-computation

RCS:

Restrict cubic splines

PIR:

Poverty income ratio

BMI:

Body mass index

OR:

Odds ratio

CI:

Confidence interval

References

  1. Kavamura VN, Esposito E. Biotechnological strategies applied to the decontamination of soils polluted with heavy metals. Biotechnol Adv. 2010;28(1):61鈥9.

    CAS听 听 听

  2. Clemens S, Ma JF. Toxic Heavy Metal and Metalloid Accumulation in Crop Plants and Foods. Annu Rev Plant Biol. 2016;67:489鈥512.

    CAS听 听 听

  3. Wang Y, Wang Y, Li R, Ni B, Chen R, Huang Y, et al. Low-grade systemic inflammation links heavy metal exposures to mortality: A multi-metal inflammatory index approach. Sci Total Environ. 2024;947: 174537.

    CAS听 听 听

  4. Martinez-Morata I, Schilling K, Glabonjat RA, Domingo-Relloso A, Mayer M, McGraw KE, et al. Association of Urinary Metals With Cardiovascular Disease Incidence and All-Cause Mortality in the Multi-Ethnic Study of Atherosclerosis (MESA). Circulation. 2024;150(10):758鈥69.

    CAS听 听 听

  5. Zhu H, Tang X, Gu C, Chen R, Liu Y, Chu H, et al. Assessment of human exposure to cadmium and its nephrotoxicity in the Chinese population. Sci Total Environ. 2024;918: 170488.

    CAS听 听 听

  6. Ma Y, Ran D, Shi X, Zhao H, Liu Z. Cadmium toxicity: A role in bone cell function and teeth development. Sci Total Environ. 2021;769: 144646.

    CAS听 听 听

  7. Shao K, Yu Y, Ritz B, Paul KC. DNA methylation biomarkers for cumulative lead exposures and cognitive impairment. Environ Res. 2024;264(Pt 2):120304.

  8. Reuben A. Childhood Lead Exposure and Adult Neurodegenerative Disease. J Alzheimers Dis. 2018;64(1):17鈥42.

    听 听 听 听

  9. Saavedra S, Fern谩ndez-Recamales 脕, Sayago A, Cervera-Barajas A, Gonz谩lez-Dom铆nguez R, Gonzalez-Sanz JD. Impact of dietary mercury intake during pregnancy on the health of neonates and children: a systematic review. Nutr Rev. 2022;80(2):317鈥28.

    听 听 听

  10. Shah S, Jeong KS, Park H, Hong YC, Kim Y, Kim B, et al. Environmental pollutants affecting children鈥檚 growth and development: Collective results from the MOCEH study, a multi-centric prospective birth cohort in Korea. Environ Int. 2020;137: 105547.

    CAS听 听 听

  11. Wang X, Han X, Guo S, Ma Y, Zhang Y. Associations between patterns of blood heavy metal exposure and health outcomes: insights from NHANES 2011鈥2016. 樱花视频. 2024;24(1):558.

    CAS听 听 听 听

  12. Zha B, Liu Y, Xu H. Associations of mixed urinary metals exposure with metabolic syndrome in the US adult population. Chemosphere. 2023;344: 140330.

    CAS听 听 听

  13. Wang G, Fang L, Chen Y, Ma Y, Zhao H, Wu Y, et al. Association between exposure to mixture of heavy metals and hyperlipidemia risk among U.S. adults: A cross-sectional study. Chemosphere. 2023;344:140334.

  14. Li W, Li X, Su J, Chen H, Zhao P, Qian H, et al. Associations of blood metals with liver function: Analysis of NHANES from 2011 to 2018. Chemosphere. 2023;317: 137854.

    CAS听 听 听

  15. Wu L, Cui F, Ma J, Huang Z, Zhang S, Xiao Z, et al. Associations of multiple metals with lung function in welders by four statistical models. Chemosphere. 2022;298: 134202.

    CAS听 听 听

  16. Chen Y, Pan Z, Shen J, Wu Y, Fang L, Xu S, et al. Associations of exposure to blood and urinary heavy metal mixtures with psoriasis risk among U.S. adults: A cross-sectional study. The Science of the total environment. 2023;887:164133.

  17. Tchounwou PB, Yedjou CG, Patlolla AK, Sutton DJ. Heavy Metal Toxicity and the Environment. In: Luch A, editor. Molecular, Clinical and Environmental Toxicology: Volume 3: Environmental Toxicology. Basel: Springer Basel; 2012. p. 133鈥64.

    听 听

  18. Clemens S, Aarts MG, Thomine S, Verbruggen N. Plant science: the key to preventing slow cadmium poisoning. Trends Plant Sci. 2013;18(2):92鈥9.

    CAS听 听 听

  19. Blood mercury levels in young children and childbearing-aged women--United States, 1999鈥2002. MMWR Morbidity and mortality weekly report. 2004;53(43):1018鈥20.

  20. Liu X, Zhang J, Si J, Li P, Gao H, Li W, et al. What happens to gut microorganisms and potential repair mechanisms when meet heavy metal(loid)s. Environmental pollution (Barking, Essex : 1987). 2023;317:120780.

  21. Bharucha AE, Dunivan G, Goode PS, Lukacz ES, Markland AD, Matthews CA, et al. Epidemiology, pathophysiology, and classification of fecal incontinence: state of the science summary for the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) workshop. Am J Gastroenterol. 2015;110(1):127鈥36.

    听 听 听

  22. Mack I, Hahn H, G枚del C, Enck P, Bharucha AE. Global Prevalence of Fecal Incontinence in Community-Dwelling Adults: A Systematic Review and Meta-analysis. Clin Gastroenterol Hepatol. 2024;22(4):712-31.e8.

    听 听 听

  23. Ten Hoor MBC, Trzpis M, Broens PMA. The Severity of Fecal Problems Is Negatively Associated With Quality of Life in a Dutch Population Without Bowel Function Comorbidities. Dis Colon Rectum. 2024;67(3):448鈥56.

    听 听

  24. Adelborg K, Veres K, Sundb酶ll J, Gregersen H, S酶rensen HT. Risk of cancer in patients with fecal incontinence. Cancer Med. 2019;8(14):6449鈥57.

    CAS听 听 听 听

  25. Wang Y, Li N, Zhou Q, Wang P. Fecal incontinence was associated with depression of any severity: insights from a large cross-sectional study. Int J Colorectal Dis. 2023;38(1):271.

    听 听 听

  26. Mizuno S, Wakabayashi H, Yamakawa M, Wada F, Kato R, Furiya Y, et al. Sarcopenia Is Associated with Fecal Incontinence in Patients with Dysphagia: Implication for Anal Sarcopenia. J Nutr Health Aging. 2022;26(1):84鈥8.

    CAS听 听 听

  27. Menees S, Chey WD. Fecal Incontinence: Pathogenesis, Diagnosis, and Updated Treatment Strategies. Gastroenterol Clin North Am. 2022;51(1):71鈥91.

    听 听 听

  28. Ditah I, Devaki P, Luma HN, Ditah C, Njei B, Jaiyeoba C, et al. Prevalence, trends, and risk factors for fecal incontinence in United States adults, 2005鈥2010. Clin Gastroenterol Hepatol. 2014;12(4):636鈥43.e1鈥2.

  29. Whitehead WE, Borrud L, Goode PS, Meikle S, Mueller ER, Tuteja A, et al. Fecal incontinence in US adults: epidemiology and risk factors. Gastroenterology. 2009;137(2):512鈥7, 7.e1鈥2.

  30. Duan W, Xu C, Liu Q, Xu J, Weng Z, Zhang X, et al. Levels of a mixture of heavy metals in blood and urine and all-cause, cardiovascular disease and cancer mortality: A population-based cohort study. Environmental pollution (Barking, Essex : 1987). 2020;263(Pt A):114630.

  31. Mahjoob DM, Knol-de Vries GE, de Boer M, van Koeveringe GA, Blanker MH. The association of fecal incontinence, constipation, and pelvic pain with the course of lower urinary tract symptoms in community-dwelling men and women. Neurourology and urodynamics.听Neurourol Urodyn. 2024;43(7):1566鈥73.

  32. Seitz V, Calata J, Mei L, Davidson ERW. Racial Disparities in Sacral Neuromodulation for Idiopathic Fecal Incontinence.听Urogynecology (Phila). 2024;30(11):873鈥9.

  33. Hiramoto B, Flanagan R, Muftah M, Shah ED, Chan WW. Centrally Distributed Adiposity as a Modifiable Risk Factor for Fecal Incontinence: United States Population-based Analysis. Clin Gastroenterol Hepatol. 2024;22(9):1908鈥16.e1.

  34. Yu L, Liu W, Wang X, Ye Z, Tan Q, Qiu W, et al. A review of practical statistical methods used in epidemiological studies to estimate the health effects of multi-pollutant mixture. Environmental pollution (Barking, Essex : 1987). 2022;306:119356.

  35. Renzetti S, Gennings C, Calza S. A weighted quantile sum regression with penalized weights and two indices. Front Public Health. 2023;11:1151821.

    听 听 听 听

  36. Trevors JT, Stratton GW, Gadd GM. Cadmium transport, resistance, and toxicity in bacteria, algae, and fungi. Can J Microbiol. 1986;32(6):447鈥64.

    CAS听 听 听

  37. Zhang S, Jin Y, Zeng Z, Liu Z, Fu Z. Subchronic Exposure of Mice to Cadmium Perturbs Their Hepatic Energy Metabolism and Gut Microbiome. Chem Res Toxicol. 2015;28(10):2000鈥9.

    CAS听 听 听

  38. Ba Q, Li M, Chen P, Huang C, Duan X, Lu L, et al. Sex-Dependent Effects of Cadmium Exposure in Early Life on Gut Microbiota and Fat Accumulation in Mice. Environ Health Perspect. 2017;125(3):437鈥46.

    CAS听 听 听

  39. He X, Qi Z, Hou H, Qian L, Gao J, Zhang XX. Structural and functional alterations of gut microbiome in mice induced by chronic cadmium exposure. Chemosphere. 2020;246: 125747.

    CAS听 听 听

  40. Xia J, Jin C, Pan Z, Sun L, Fu Z, Jin Y. Chronic exposure to low concentrations of lead induces metabolic disorder and dysbiosis of the gut microbiota in mice. The Science of the total environment. 2018;631鈥632:439鈥48.

    听 听 听

  41. Eggers S, Safdar N, Sethi AK, Suen G, Peppard PE, Kates AE, et al. Urinary lead concentration and composition of the adult gut microbiota in a cross-sectional population-based sample. Environ Int. 2019;133(Pt A): 105122.

    CAS听 听 听 听

  42. Duan H, Yu L, Tian F, Zhai Q, Fan L, Chen W. Gut microbiota: A target for heavy metal toxicity and a probiotic protective strategy. The Science of the total environment. 2020;742: 140429.

    CAS听 听 听

  43. Deng Y, Lin X, Zhou J, Li M, Fu Z, Song D. Concurrent serum lead levels and cognitive function in older adults. Front Neurosci. 2023;17:1180782.

    听 听 听 听

  44. Song S, Liu N, Wang G, Wang Y, Zhang X, Zhao X, Chang H, Yu Z, Liu X. Sex Specificity in the Mixed Effects of Blood Heavy Metals and Cognitive Function on Elderly: Evidence from NHANES. Nutrients. 2023;15(13):2874.

  45. He YS, Cao F, Musonye HA, Xu YQ, Gao ZX, Ge M, et al. Serum albumin mediates the associations between heavy metals and two novel systemic inflammation indexes among U.S. adults. Ecotoxicol Environ Saf. 2024;270:115863.

  46. Li Z, Chen X, Huang J, Cheng F, Wu Z, Yuan L, et al. Association between dietary inflammatory index and fecal incontinence in American adults: a cross-sectional study from NHANES. 2024;2005鈥2010:11.

  47. Zalups RK, Ahmad S. Molecular handling of cadmium in transporting epithelia. Toxicol Appl Pharmacol. 2003;186(3):163鈥88.

    CAS听 听 听

Acknowledgements

Sincere thanks to the NHANES staff and participants for their invaluable contributions.

Funding

No Funding.

Author information

Authors and Affiliations

Authors

Contributions

Z.G.L performed the described studies, analyzed the data, and prepared the manuscript. S.Q.P and D.C.Z conducted the statistical analysis and revised the manuscript. L.L.L checked the data, review & editing and approved the final manuscript.

Corresponding author

Correspondence to Lulin Liu.

Ethics declarations

Ethics approval and consent to participate

All NHANES projects receive approval from the NCHS Research Ethics Review Board, and participants provide written consent upon enrollment (NHANES鈥擭CHS Research Ethics Review Board Approval (cdc.gov)).

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.

Additional information

Publisher鈥檚 Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary Information

Supplementary Material 1:听Table S1.LODs of blood Cd, Pb and Hg in NHANES 2005-2010.听Table S2. Proportion of blood Cd, Pb, and Hg below the limit of detection in NHANES 2005-2010.听Figure S1. Directed acyclic graph. PIR, poverty income ratio; BMI, body mass index.听Figure S2. Correlation between heavy metals in blood.听Figure S3. Quantile g-computation scaled weights of blood Cd, Pb, and Hg.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article鈥檚 Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article鈥檚 Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit .

About this article

Cite this article

Li, Z., Peng, S., Zhang, D. et al. Association between blood heavy metals and fecal incontinence in American adults:听A population-based study. 樱花视频 24, 3489 (2024). https://doi.org/10.1186/s12889-024-20958-z

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s12889-024-20958-z

Keywords