Metal Mixture Inflammatory Index and diabetes risk in US adults: a cross-sectional analysis of NHANES 1999–2020 and development of a LASSO-based prediction model

Exploring the associations of serum concentrations of PCBs, PCDDs, and PCDFs with walking speed in the U.S. general population: Beyond standard linear models

To investigate the association between high-sensitivity C-reactive protein (Hs-CRP) levels and the risk of postoperative delirium (POD) following general anesthesia. This retrospective cross-sectional study included 644 patients who underwent general anesthesia. Univariate and multivariate logistic regression analyses were performed to evaluate the relationship between Hs-CRP and POD, with subgroup analyses used to assess stratified associations. Receiver operator characteristic (ROC) curve analysis was employed to assess the predictive efficacy of Hs-CRP for POD. Restricted cubic spline (RCS) analysis was conducted to explore the linear relationship between the log-transformed Hs-CRP (Log10Hs-CRP) and POD risk. The total population consisted of 644 individuals with a mean age of 64.02 ± 13.20 years, 506 (78.60%) of whom were male, and 114 patients (17.7%) had POD. Compared to the lower Hs-CRP group, patients in the higher Hs-CRP group exhibited higher age, heart rate, white blood cell count, blood urea nitrogen, creatinine, uric acid, fasting glucose, hemoglobin A1c, fibrinogen, D-dimer, and a higher prevalence of CKD, but lower hemoglobin, high-density lipoprotein cholesterol, albumin and estimated glomerular filtration rate. Additionally, the prevalence of POD was higher in the higher Hs-CRP group (24.7% vs. 9.5%, p < 0.001). Multivariate logistic regression confirmed that elevated Hs-CRP and its forms (Log10Hs-CRP, standardized Hs-CRP, and higher Hs-CRP group) consistently increased the risk of POD across all adjusted models (p < 0.05). Stratified analyses further highlighted significant associations between Hs-CRP and POD in specific subgroups, notably in patients aged ≥65 years, female patients, and those with or without hypertension, diabetes, or stroke history, and without chronic kidney disease (p < 0.05). ROC curve analysis demonstrated that Hs-CRP had a significant predictive ability for POD in the overall population (AUC = 0.646), as well as in male (AUC = 0.644) and female patients (AUC = 0.654). Additionally, RCS analysis indicated a linear positive association between Log10Hs-CRP and POD risk (p = 0.003, nonlinear p = 0.896). Elevated Hs-CRP levels are significantly associated with an increased risk of POD following general anesthesia.

Introduction: The association between obesity and wet overactive bladder (wet OAB) was few and was also inconsistent and controversial in sex differences. This study aimed to ascertain the specific association between obesity and wet OAB for females and males using five obesity measures. Methods: This cross-sectional study included 29,041 participants from the 2005–2020 National Health and Nutrition Examination Survey database. The outcome was the risk of wet OAB. Five obesity measures were exposure using quintile, including body mass index (BMI), waist-to-stature ratio (WSR), body fat percentage (BFP), fat mass, and lean mass. The associations were elucidated using weighted logistic regression models and restricted cubic spline (RCS) analysis. Results: The elevated BMI, WSR, BFP, and fat mass were positively associated with the risk of wet OAB in both sexes, which was evident in females. Interestingly, lean mass was adversely associated with the risk of wet OAB in both sexes. In RCS analysis about BMI, WSR, BFP, and fat mass, monotonically increasing nonlinear associations were found in males, while positive linear associations were found in females. Besides, negative linear and nonlinear relationships were shown between lean mass and the risk of wet OAB in females and males, respectively. Conclusions: Obesity was positively associated with the risk of wet OAB in both sexes. Controlling BMI, WSR, BFP, fat mass, and strengthening lean mass may help prevent the development of wet OAB.

Sedentary behavior and impaired thyroid hormone sensitivity are linked to a variety of comorbid conditions; however, the exact nature of their relationship remains inadequately studied. This study sought to examine the association between sedentary time and thyroid hormone sensitivity. Utilizing a cross-sectional design, the study analyzed data from U.S. participants in the National Health and Nutrition Examination Survey (NHANES) conducted between 2007 and 2012. The Least Absolute Shrinkage and Selection Operator (LASSO) regression and the Boruta algorithm were employed to screen out confounding factors closely associated with sedentary time and the parametric thyroid feedback quantile-based index (PTFQI). Multivariate linear regression models were applied to analyze the association between sedentary time and indicators of thyroid hormone sensitivity. After adjusting for all confounding factors, restricted cubic spline (RCS) curves were utilized to further explore the potential non-linear relationship between sedentary time and indicators of thyroid hormone sensitivity. Additionally, subgroup analyses and interaction tests were conducted to further explore this association. A total of 22 significant confounding factors were identified through LASSO regression and the Boruta algorithm. Among these potential confounding factors, body mass index (BMI) occupied a central position, and it partially mediated the association between sedentary time and the PTFQI. RCS analysis indicated that, after adjusting for all covariates, there was a significant linear association between sedentary time and PTFQI in men (P for overall = 0.002, P for non-linear = 0.085). In contrast, in women, the relationship presented an "inverted U-shaped" curve, which was not statistically significant (P for overall > 0.05). Moreover, the results of the interaction analysis revealed a significant interaction effect of race on the association between sedentary time and PTFQI (P for interaction = 0.004). In this study, we found a positive association between impaired thyroid hormone sensitivity and sedentary time in men after adjusting for confounders, and BMI partially mediated this positive association. Additionally, the factor of race exhibited a significant interaction effect on the association between sedentary time and the PTFQI.

Circadian syndrome comprises metabolic risk factors and comorbidities associated with circadian rhythm disruption. However, whether overall diet quality is associated with circadian syndrome remains unclear. This study aimed to investigate the association between the Healthy Eating Index-2015 (HEI-2015), an indicator of overall diet quality, and circadian syndrome to address this knowledge gap. This cross-sectional study used data from the National Health and Nutrition Examination Survey conducted from 2005 to 2018, including adults aged 20 years and older. The HEI-2015 was used to assess individual dietary quality, while circadian syndrome was defined based on the components of metabolic syndrome, along with sleep deprivation and depression. In weighted multivariable logistic regression, HEI-2015 was modeled both as a continuous variable and in tertiles, with HEI-2015 as the independent variable and circadian syndrome (yes/no) as the dependent variable. Restricted cubic spline (RCS) analysis was used to examine potential dose–response relationships, and subgroup analyses were performed by age, sex, physical activity, body mass index, trouble sleeping, cardiovascular disease, chronic kidney disease, and cancer. A total of 11,557 participants (mean age 48.7 years; 51.4% female) were included in the study, of whom 3317 were defined as having circadian syndrome. The proportions of participants in HEI-2015 tertiles 1, 2, and 3 were 33.3%, 33.3%, and 33.4%, respectively. In the fully adjusted model, HEI-2015 was inversely associated with circadian syndrome when treated as a continuous variable (OR: 0.90, 95% confidence interval (CI): 0.86–0.94), and when categorized into tertiles, the odds ratio (OR) for the highest tertile compared with the lowest was 0.78 (95% CI: 0.67–0.90). RCS analysis indicated a linear negative association (P for nonlinearity = .11). The results of subgroup analyses were consistent across various subgroups. Among U.S. adults, higher HEI-2015 scores were linearly associated with lower risk of circadian syndrome. Further validation in more diverse populations is needed, and clinicians may consider assessing dietary quality in patients with circadian syndrome to optimize management strategies.

This study aimed to investigate the relationship between lipoprotein(a) [Lp(a)] levels and non-alcoholic fatty liver disease (NAFLD), and to analyze its linear association and subgroup differences. This cross-sectional analysis was based on data from 2308 participants in the National Health and Nutrition Examination Survey (NHANES) III. Multivariate logistic regression models were used to assess the association between Lp(a) and NAFLD, adjusting for demographic factors, lifestyle behaviors, comorbidities, and biomarkers. Subgroup analyses were conducted based on age, sex, body mass index (BMI), diabetes, and hypertension. Restricted cubic spline (RCS) regression model was used to explore the nonlinear relationship between Lp(a) and NAFLD. Higher Lp(a) levels were significantly associated with a lower risk of NAFLD. In the fully adjusted model, compared to the lowest quartile group (Q1), the third and fourth quartiles (Q3 and Q4) had significantly reduced risks of NAFLD [Q3: OR = 0.701, 95% CI 0.511, 0.961; P = 0.027; Q4: OR = 0.605, 95% CI 0.438, 0.835; P = 0.002]. Subgroup analysis showed that the association between higher Lp(a) levels and reduced NAFLD risk was significant in individuals aged 50 years and older, those with BMI ≥ 30 kg/m2, non-diabetics, and those with hypertension. RCS analysis further confirmed a linear negative association between Log10Lp(a) and NAFLD risk (P = 0.029, P nonlinearity = 0.888). There is a significant linear negative association between Lp(a) levels and the risk of NAFLD, suggesting that Lp(a) may serve as a potential biomarker for assessing NAFLD risk.

Frailty, characterized by functional decline and disability, is an emerging public health concern in aging populations. Chronic inflammation and low high-density lipoprotein cholesterol (HDL-C) levels are key contributors to the progression of frailty. This study aims to examine the association between the ratio of high-sensitivity C-reactive protein (hs-CRP) to HDL-C and frailty among middle-aged and older adults in the United States. Our study included participants aged 45 years and older from the 2015-2020 National Health and Nutrition Examination Survey (NHANES). Logistic regression and restricted cubic spline (RCS) analysis were utilized to assess the relationship between the hs-CRP/HDL-C ratio and frailty, adjusting for potential confounding covariates. Mediation analysis was performed to determine whether plasma proteins mediated this association. Least absolute shrinkage and selection operator (LASSO) regression was employed to identify variables strongly correlated with frailty, and a nomogram was subsequently developed based on these variables. Our study included 3,626 middle-aged and older participants, among whom 787(21.7%) were identified as frailty. After adjusting for all covariates, a high hs-CRP/HDL-C ratio was identified as a significant risk factor for frailty (OR = 1.736, 95% CI: 1.009-2.988). RCS analysis disclosed a nonlinear correlation between the hs-CRP/HDL-C ratio and frailty incidence. Furthermore, mediation analysis suggested that albumin and globulin partially mediated this association, accounting for 37.82% and 11.23% of the indirect effect, respectively. A nomogram, constructed using variables selected via LASSO regression, exhibited promising discriminative ability, with an area under the curve (AUC) of 79.7% (95% CI: 77.7-81.75%). Our findings suggest that a higher hs-CRP/HDL-C ratio is associated with an increased risk of frailty among middle-aged and older adults. Albumin and globulin partially mediate this relationship. Additionally, the nomogram developed in our study shows strong predictive ability for identifying individuals at high risk of frailty in this population.

BackgroundRheumatoid arthritis (RA) is a chronic autoimmune disease with a higher prevalence in women. Triglycerides, key indicators of lipid metabolism, are linked to inflammation and metabolic disorders, both contributing to RA pathogenesis. However, the association between triglyceride levels and RA prevalence in women remains unclear. This study analyzes this association using NHANES (1999–2018) data to provide evidence for prevention and personalized intervention strategies.MethodsThis study utilized data from the National Health and Nutrition Examination Survey (NHANES) spanning 1999 to 2018. It included 10,728 female participants, of whom 639 were diagnosed with RA. Triglyceride levels were categorized into four quartiles (Q1 to Q4), and multivariable logistic regression models were used to analyze the association between triglyceride levels and RA prevalence in women. Restricted cubic spline (RCS) analyses were performed to evaluate the potential nonlinear association between triglyceride levels and RA prevalence. Subgroup and interaction analyses were conducted to further investigate the association across different populations.ResultsAmong the 639 RA patients, higher triglyceride levels were significantly positively associated with RA prevalence in women. In the unadjusted model, elevated triglyceride levels were significantly associated with an increased RA prevalence (OR: 1.30, 95% CI: 1.04–1.61, P = 0.019). This association remained significant in the adjusted model, with the highest quartile showing a substantially higher risk compared to the lowest quartile (OR: 2.46, 95% CI: 1.22–4.95, P for trend = 0.04). RCS analyses indicated a linear association between triglyceride levels and RA prevalence (P for nonlinearity = 0.19). Subgroup analyses revealed consistent trends across various subgroups, with no significant interactions observed (all interaction P-values > 0.05).ConclusionThis study demonstrates a significant positive association between elevated triglyceride levels and RA prevalence in women, with a linear trend observed in this association. Future research should further investigate the role of triglyceride levels in the pathogenesis of RA and explore potential intervention pathways.

Systemic inflammation is increasingly recognized as a critical factor in the development of coronary heart disease (CHD). The systemic inflammation response index (SIRI) integrates the neutrophil, lymphocyte, and monocyte counts to provide a comprehensive inflammatory marker. However, the relationship between the SIRI and CHD risk remains unclear. This study aimed to investigate the association between SIRI and CHD risk in adults using data from the 2012 to 2018 National Health and Nutrition Examination Survey (NHANES) 2012–2018. Restricted cubic spline (RCS) analysis was conducted to explore potential nonlinear relationships, and subgroup analyses were used to evaluate the demographic and clinical modifiers. Logistic regression analysis was performed to assess the association between SIRI and CHD risk after adjusting for demographic, behavioral, and clinical covariates. RCS analysis examined nonlinear trends and subgroup analyses stratified the results by age and sex. Of the 8612 participants initially screened, 1121 were included in the final analysis. Elevated SIRI levels were significantly associated with higher CHD risk (odds ratio [OR] = 1.14, 95% confidence interval [CI]: 1.05–1.25, P < .001). RCS analysis showed a linear relationship between the SIRI and CHD risk (P for nonlinearity = .056). Subgroup analysis demonstrated stronger associations in males (OR = 1.21, 95% CI: 1.10–1.34) and individuals aged ≥55 years (OR = 1.18, 95% CI: 1.08–1.29), whereas no significant associations were found in female or younger populations. This study underscores the utility of the SIRI as a potential biomarker for CHD risk. The linear association between the SIRI and CHD risk emphasizes the importance of systemic inflammation, particularly in males and older adults. Further studies should investigate targeted anti-inflammatory interventions to potentially reduce CHD risk. However, due to the cross-sectional design of this study, it is important to note that no temporal or causal relationship can be inferred between SIRI levels and CHD risk intention-to-treat.

The association between micronutrient intake and the risk of periodontitis has received much attention in recent years. However, most studies focused on the linear relationship between them. This study aimed to explore the dose–response association between micronutrient intake and periodontitis. A total of 8959 participants who underwent a periodontal examination, and reported their micronutrient intake levels were derived from the US National Health and Nutrition Examination Survey (NHANES, 2009–2014) database. Logistic regression was performed to evaluate associations between micronutrient intake and periodontitis after propensity score matching (PSM), and restricted cubic splines (RCS) analysis was conducted to explore the dose–response associations. Following PSM, 5530 participants were included in the RCS analysis. The risk of periodontitis was reduced with sufficient intake of the following micronutrients: vitamin A, vitamin B1, vitamin B2, and vitamin E. In addition, the risk of periodontitis was increased with excessive intake of the following micronutrients: vitamin B1 (1.8 mg/day, males; 1.3 mg/day, females), vitamin C (90 mg/day, males), and copper (1.1 mg/day, combined). In conclusion, a linear association was found between vitamin A, vitamin B2, vitamin C, and copper and periodontitis—namely, a sufficient intake of vitamin A and vitamin B2 might help reduce the prevalence of periodontitis; by contrast, a high intake of vitamin C and copper increased the risk. In addition, a nonlinear dose–response association was found for the incidence of periodontitis with vitamin B1 and vitamin E. When within reasonable limits, supplemental intake helped reduce the prevalence of periodontitis, while excessive intake did not help significantly and might even increase the risk. However, confounding factors, such as health awareness, should still be considered.

ABSTRACT: Background Erectile dysfunction (ED) is associated with metabolic disorders like hypertension and diabetes. The lipid accumulation product (LAP), a marker of visceral fat and dyslipidemia, has not been well studied in relation to ED in these populations. This study examined the relationship between LAP and ED. Methods A cross-sectional analysis of National Health and Nutrition Examination Survey (NHANES) 2001–2004 data included 756 men with hypertension or diabetes. Weighted multivariable logistic regression and restricted cubic spline (RCS) analysis evaluated LAP-ED associations, with subgroup analysis for effect modification. Results ED prevalence was 43.65% (330/756). LAP correlated positively with ED risk (continuous: OR = 1.005, 95%CI:1.000–1.005). Highest vs lowest LAP quartile (Q4 vs Q1) showed 2.92-fold higher ED risk (OR = 2.92, 95%CI:1.21–7.06). RCS analysis indicated linear association (P for non-linearity = 0.290). Subgroup analysis showed no significant interactions. Conclusion This study demonstrates a positive correlation between LAP and ED in men with diabetes or hypertension; further studies are needed to confirm findings and explore mechanisms.

Objective:This study aimed to evaluate the association of conicity index (C-index), a marker of abdominal obesity, with hearing impairment (HI) in US adults using data from the National Health and Nutrition Examination Survey (NHANES).Methods:We conducted a cross-sectional investigation using data from nine NHANES cycles spanning from 2001 to 2018. The C-index was used as the independent variable, whereas HI—defined as a pure-tone average hearing threshold exceeding 25 dB HL—was the outcome measure. Multivariable logistic regression models were used to assess the association between C-index and HI, adjusting for potential confounders including age, sex, race/ethnicity, hypertension, diabetes, total cholesterol, haemoglobin and blood urea nitrogen. Dose–response relationships were evaluated using trend tests (P for trend) and restricted cubic spline (RCS) analysis. Subgroup analyses were performed to assess potential interaction effects.Results:A total of 7394 adults aged 20–69 were included. Higher C-index values were significantly associated with an increased prevalence of HI. In the fully adjusted model, each unit increase in C-index was associated with 7.35-fold higher odds of HI (95% CI: 3.03–17.82, P < 0.01). When stratified into tertiles, individuals in the highest tertile had a 57% higher likelihood of HI compared to the lowest tertile (Odds Ratio = 1.57, 95% Confidence Interval: 1.14–2.18, P < 0.01). RCS analysis indicated a significant non-linear association (P for non-linearity < 0.05) with an inflection point at a C-index of 1.17. Subgroup analysis revealed significant interaction effects of C-index with gender, diabetes and hypertension (P for interaction < 0.05) but not with age (P > 0.05).Conclusion:Higher C-index values are independently associated with greater odds of HI. Given the rising burden of obesity and its metabolic consequences, the C-index may serve as a practical tool for HI risk assessment, especially in populations with cardiometabolic risk factors.

Background:Statin therapy is associated with an increased risk of new-onset diabetes (NOD), possibly due to a reduction in coenzyme Q10 (CoQ10) levels as a result of statin use. This study aimed to investigate the relationship between exogenous CoQ10 supplementation and the development of NOD.Methods:This study included 4394 participants from the National Health and Nutrition Examination Survey (NHANES). Baseline characteristics were compared between those with and without NOD and between those with and without CoQ10. Univariate logistic regression was performed to identify factors associated with NOD. Two models were used for confounding factors, including demographics and various covariates. Multifactor logistic regression further assessed the association between CoQ10 supplementation and NOD. Additionally, restricted cubic spline (RCS) analysis was conducted to evaluate the potential nonlinear relationship between daily CoQ10 dose and NOD.Results:Univariate logistic regression showed an association between CoQ10 supplementation and a reduced risk of NOD (odds ratio [OR] = 0.323, 95% confidence interval [CI] 0.157–0.668, p = 0.003), which remained significant after adjustments in model 1 (OR = 0.344, 95% CI 0.160–0.737, p = 0.006) and model 2 (OR = 0.232, 95% CI 0.057–0.942, p = 0.041). There was no evidence of a linear association between daily CoQ10 dose and NOD in logistic regression analysis (OR = 0.999, 95% CI 0.994–1.004, p = 0.720), and no evidence of a nonlinear correlation in the RCS analysis (p > 0.05).Conclusions:CoQ10 supplementation in individuals taking statins was associated with a reduced risk of NOD, and this association was independent of the CoQ10 dose.

Periodontitis and metabolic syndrome (MetS) are both linked to inflammation, but their association remains unclear. This study aimed to explore the association between periodontitis and MetS prevalence and evaluate its impact on the prognosis of all-cause and cardiovascular mortality in MetS. Data were obtained from the National Health and Nutrition Examination Survey (NHANES) database. Logistic regression analysis was used to investigate the association between periodontitis and the prevalence of MetS, while Cox regression analysis was applied to assess the association between periodontal status and the poor prognosis in individuals with MetS. Furthermore, restricted cubic spline (RCS) analysis was performed to evaluate the linear and nonlinear associations between periodontal parameters, including attachment loss (AL) and probing depth (PD), and the prevalence and mortality of MetS. A total of 9,270 individuals were included in the analysis. Individuals with periodontitis had a higher prevalence of MetS compared to those without periodontitis (OR=1.24, 95% CI: 1.08-1.43). Cox regression analysis revealed that periodontitis was associated with an increased risk of all-cause mortality (HR=2.03, 95% CI:1.40-2.92) and cardiovascular mortality (HR=2.32, 95% CI:1.05-5.10) among individuals with MetS. Furthermore, the RCS analysis demonstrated that AL had a nonlinear association with the risk of prevalence, all-cause mortality and cardiovascular mortality in MetS (P for nonlinearity < 0.05). However, PD was linearly associated with the increased risks of these outcomes (P overall < 0.05). Periodontitis is associated with an increased risk of MetS, as well as higher risks of all-cause and cardiovascular mortality.

BackgroundRheumatoid arthritis (RA) is a chronic, systemic autoimmune inflammatory disorder. Diet is recognized as a modifiable factor that may influence inflammation and potentially accelerate RA progression. Nevertheless, the effects of diverse dietary patterns and their combined impact on RA progression and long-term mortality remain inadequately understood. This study examined the association between dietary patterns and mortality in patients with RA, focusing on the Healthy Eating Index (HEI-2015) and Dietary Inflammatory Index (DII) and evaluating their combined effects.MethodsThe analysis included 2,069 patients with RA from the National Health and Nutrition Examination Survey (NHANES) spanning 2003–2018. Weighted multi-variable Cox regression models estimated the relationship between the DII, HEI-2015, combined dietary patterns, and all-cause mortality in patients with RA. Linear associations between the DII, HEI-2015, and all-cause mortality were analyzed using restricted cubic splines (RCS). Dietary factors associated with mortality were identified through the Least Absolute Shrinkage and Selection Operator (LASSO) method, and subgroup and sensitivity analyses were conducted to strengthen the findings.ResultsParticipants had a median age of 59 years (IQR: 48–69), with 42.1% male. Adjusting for potential confounders, the hazard ratio (HR) for individuals adhering to healthy and anti-inflammatory dietary patterns, as opposed to unhealthy and pro-inflammatory patterns, was 0.70 (95% CI: 0.53–0.92; adjusted P = 0.01; trend P = 0.02). In weighted Cox analyses of the DII and HEI-2015, higher quartiles showed no significant mortality risk difference from the lowest quartiles. The LASSO-Cox model identified 12 dietary components predictive of all-cause mortality in patients with RA, with an AUC of 0.749 (0.682–0.815) at 1 year, 0.763 (0.724–0.802) at 3 years, 0.783 (0.749–0.802) at 5 years, and 0.868 (0.712–0.938) for all death events. Kaplan-Meier analysis revealed that the low-risk dietary group exhibited significantly lower mortality compared to the high-risk group (P < 0.001).ConclusionsThese findings suggest that combining a higher HEI-2015 with a lower DII score correlates with reduced all-cause mortality risk among patients with RA, supporting dietary modification as a potential strategy to prevent premature death in this population.Graphic abstractSupplementary InformationThe online version contains supplementary material available at 10.1186/s13075-024-03462-y.