Nonlinear Association Research Articles

Nonlinear relationship between Hemoglobin-to-Age Ratio and all-cause mortality in patients with septic shock: A retrospective cohort study in the MIMIC-IV database.

Previous studies have shown that both age and hemoglobin are closely associated with the prognosis of septic shock. A recent study found that hemoglobin may change with age. Hemoglobin-to-Age Ratio (HAR) takes both age and hemoglobin into consideration as essential factors. So far, the effect of HAR on the prognosis of septic shock is still unclear. This research aimed to investigate the association between the HAR and the prognosis of patients with septic shock. Cox proportional hazards regression analysis, restricted cubic spline, Kaplan-Meier survivor analysis and stratified interaction analysis were used to elucidate the relationship between the HAR and prognosis of patients with septic shock. There is a nonlinear association between the HAR and mortality within 28 days after intensive care unit admission. When the HAR was lower than 0.13, mortality within 28 days after ICU admission decreased significantly as the HAR increased. When the HAR was higher than 0.13, the HAR was not a protective factor for mortality within 28 days after ICU admission. In patients with septic shock, the HAR was more effective in reducing the risk of death in patients with atrial fibrillation than in patients without atrial fibrillation. There is a nonlinear association between the HAR and mortality within 28 days after intensive care unit admission. When the HAR was at a low level, mortality within 28 days after ICU admission decreased significantly as the HAR increased. When the HAR was at high levels, the HAR might not be a protective factor for mortality within 28 days after ICU admission. In patients with septic shock, the HAR was more effective in reducing the risk of death in patients with atrial fibrillation than in patients without atrial fibrillation.

Association of oxygen saturation and mortality in patients with acute respiratory failure.

The variability and disparities in the recommended targets across different international guidelines suggest the optimal oxygen saturation (SpO2) target for acute respiratory failure (ARF) patients be further explored. To explore the association between SpO2 and in-hospital mortality of ARF patients, as well as to determine the optimum SpO2 for ARF patients. In this cohort study, 3,225 ARF patients were included at the end of the follow-up; among them, and 1,249 patients survived and 1,976 died. The restricted cubic spline (RCS) was drawn to show the nonlinear association between the median SpO2 and the risk of in-hospital mortality of ARF patients and to identify the optimal range of SpO2. Cox regression was applied to identify the association between the median SpO2 and the risk of in-hospital mortality in ARF patients. Kaplan-Meier curves were plotted to identify the in-hospital mortality of ARF patients. The in-hospital mortality rate was 61.2% in all ARF patients at the end of the follow-up. The median SpO2 was associated with decreased risk of in-hospital mortality of ARF patients after adjusting for confounders (hazard ratio (HR) = 0.95, 95% confidence interval (95% CI): 0.93-0.97). The median SpO2 was non-linearly correlated with the in-hospital mortality of ARF patients. The overall survival (OS) was higher in the 96-98% group. A median SpO2 ≤ 96% was associated with an increased risk of in-hospital mortality in ARF patients accompanied by malignant cancer (HR = 1.55, 95% CI: 1.24-1.94), renal failure (HR = 1.45, 95% CI: 1.24-1.70), chronic obstructive pulmonary disease (COPD; HR = 1.70, 95% CI: 1.27-2.28) and atrial fibrillation (AF; HR = 1.25, 95% CI: 1.02-1.53). The median SpO2 > 98% was associated with an elevated risk of in-hospital mortality in ARF patients accompanied by AF (HR = 1.22, 95% CI: 1.04-1.44). The median SpO2 was linked to a decreased risk of in-hospital mortality in ARF patients.

Association between dyslipidemia and depression: a cross-sectional analysis of NHANES data from 2007 to 2018

BackgroundThe relationship between depression and dyslipidemia remains controversial, with inconsistent findings across studies. This study aimed to investigate the association between blood lipid levels and depression using data from the National Health and Nutrition Examination Survey (NHANES) spanning from 2007 to 2018.MethodsThis cross-sectional study included 12,819 adult participants from NHANES. Depression was assessed using a nine-item depression screening instrument. Serum lipid levels, including total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG), were measured using Roche modular P and Roche Cobas 6000 chemistry analyzers. Survey-weighted multiple logistic regression was used to assess the relationships between serum lipid levels and depression.ResultsWe observed a statistically significant negative association between HDL levels and depression (odds ratio [OR]: 0.72, 95% confidence interval [CI]: 0.58–0.90). After adjustments for covariates, HDL-C, TG, and the triglyceride glucose (TyG) index showed significant associations with depression (ORs: 0.66, 1.08, and 1.01, respectively). A linear correlation was observed between HDL-C levels and depression (P < 0.01), while TG levels and the TyG index exhibited nonlinear associations (p < 0.01 and p < 0.05, respectively). No significant positive associations were observed between increased TC or LDL-C levels and the risk of depression.ConclusionsHigh HDL-C levels were negatively associated with depression, while TG levels and the TyG index were positively associated with depression. Clinical attention should be given to the detection of lipid levels in patients with depression.

Serum concentrations of different or multiple vitamins and Sarcopenia risk among US adults: insights from NHANES

BackgroundThe relationship between serum concentrations of different or multiple vitamins and sarcopenia remains underexplored. This investigation evaluates potential links between serum concentrations of different or multiple vitamins and sarcopenia prevalence among adults in the United States.MethodsUtilizing a cross-sectional design, this research draws from the National Health and Nutrition Examination Survey (NHANES) dataset of 2003–2006, encompassing 5,060 participants with comprehensive serum vitamin A, E, B9, B12, C, and D concentrations, alongside sarcopenia and covariate measurements. Participant stratification into distinct vitamin co-exposure clusters was achieved through K-means clustering. Analytical models, including weighted logistic regression, restricted cubic splines (RCS), weighted quantile sum regression (WQS), quantile g-computation (Q-gcomp), and Bayesian kernel machine regression (BKMR), were employed to evaluate the association between serum concentrations of different or multiple vitamins and sarcopenia risk, with an emphasis on nonlinearity.ResultsIn this study, sarcopenia was detected in 681 individuals (13.46%). Logistic regression results did not demonstrate any linear association between individual vitamin levels and sarcopenia risk (PFDR > 0.05). Contrastingly, the RCS model unveiled significant non-linear relationships for vitamins A and D (P_non-linear < 0.05). The K-means clustering results showed that participants in high-level vitamin exposure group had lower sarcopenia risk compared with those in low-level vitamin exposure group (OR (95% CI): 0.582 (0.397, 0.852)). Additionally, higher serum concentrations of different or multiple vitamins correlated inversely with sarcopenia risk (P_trend = 0.002). This inverse association was corroborated by WQS, Q-gcomp, and theBKMR models and remained consistent upon sensitivity analysis.ConclusionsThis study elucidates an inverse correlation between serum concentrations of different or multiple vitamins and sarcopenia risk, emphasizing a non-linear association, particularly with suboptimal vitamin D concentrations. Given the limitations of the NHANES study, further researches are required to clarify the existence of these relationships.

Association between non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio and sarcopenia based on NHANES

The ratio of non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol, or NHHR, has garnered increased attention because of its connection to metabolic diseases. It is yet unknown, nevertheless, how NHHR and sarcopenia relate to one another in the US population. Examining the relationship between NHHR and the prevalence of sarcopenia in the US population is the main goal of this study. Utilizing information gathered from the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2018, a study was conducted to look at the connection between NHHR and sarcopenia in the US population. The individuals’ baseline features were categorized based on whether or not sarcopenia was present. We used subgroup analysis, restricted cubic spline (RCS), and weighted logistic regression to examine the connection between NHHR and sarcopenia prevalence. Sensitivity analysis was used to confirm that the study’s findings were reliable and consistent. R (version 4.2.3) was used for all analyses, and P < 0.05 was used to indicate statistical significance. There were 10,087 individuals in all, 9,187 of whom were not sarcopenic and 900 of whom were. Sarcopenic patients were generally older, predominantly of Mexican American descent, and had lower educational levels. These patients were generally less active and exhibited higher levels of total cholesterol and BMI, along with lower HDL levels. Following complete adjustment, the weighted logistic regression model indicated that a 7% increased risk of sarcopenia was linked to every unit rise in NHHR (OR = 1.07, 95% CI = 1.02–1.13). An inflection point was identified at 2.90 by RCS analysis, which revealed a nonlinear association between NHHR and the prevalence of sarcopenia. Subgroup analysis showed that, regardless of the demographic group, there was a continuous positive correlation between NHHR and the prevalence of sarcopenia. The results of the interaction test provided evidence in favor of NHHR functioning as a stand-alone risk factor for sarcopenia. Our research suggests that a higher prevalence of sarcopenia may be linked to an increase in NHHR. Consequently, NHHR may function as a separate risk factor for sarcopenia.

Nonlinear associations between street-level greenery quantity and quality, physical activity, and sedentary behaviour in Chinese middle-aged and older adults: A socioeconomic equity perspective

Despite studies investigating the relationships among greenery, physical activity, and sedentary behaviour, it remains unclear whether such associations are nonlinear. Scant attention has also been paid to the role of greenery from a socioeconomic equity perspective. Thus, we assessed possible nonlinear associations between street-level greenery, physical activity, and sedentary behaviour in middle-aged and older adults. We also examined whether and how street-level greenery may increase socioeconomic equity in physical activity and sedentary behaviour. Data on physical activity and sedentary behaviour were obtained from the WHO Study on Global Ageing and Adult Health in Shanghai, China. The quantity and quality of street-level greenery were assessed using segmented street-view images based on deep learning methods. The results of fitting gradient-boosting decision trees showed that street-level greenery quantity was positively related to physical activity. We observed a steep increase in physical activity at low greenery quantity and flattening out at higher quantity. Street-level greenery quality was negatively related to sedentary behaviour. While sedentary behaviour did not change significantly at low greenery quality, the decrease became steep at higher quality. The greenery association was stronger for low incomers and those in deprived neighbourhoods.

The association of thyroid stimulating hormone and body fat in adults.

Thyroid stimulating hormone (TSH) has been proven to be closely associated with metabolic abnormalities, including obesity. The objective of this investigation was to scrutinize the intricate association between TSH concentration and obesity, within the adult population. The study focused on a comprehensive examination of the relationship, delving into specific adiposity parameters such as total percent fat (TPF), android percent fat (APF), and gynoid percent fat (GPF). This study included 809 participants aged 20 and above with normal TSH values from the National Health and Nutrition Examination Survey (NHANES) 2007-2012. Multivariable linear regression models examined the associations of TSH concentration with TPF, APF, and GPF. Subgroup analyses, stratified by sex, were performed using multivariable linear regression. Fitted smoothing curves and generalized additive models addressed non-linear relationships between TSH and TPF, APF, and GPF. In fully adjusted models, a significant positive association was observed between TPF and TSH (β = 0.01, 95% CI: 0.00-0.02, p<0.05), while no such association was evident in APF and GPF. Upon sex stratification, females exhibited significant positive correlations between TSH and TPF, APF, and GPF (all p < 0.001), contrasting with males where no such correlations were found. Notably, a non-linear association was identified in males, specifically a U-shaped curve (inflection point: 32.6%) for TSH and APF. The study unveiled a statistically significant positive association between TSH and TPF in adults. Upon sex stratification, similar statistically significant relationships were observed between TSH and adiposity (TPF, APF, GPF) in females, while males exhibited a U-shaped non-linear relationship between TSH and APF.

Prevalence of mental disorders and their associations with age at diagnosis and time since diagnosis of nasopharyngeal cancer.

Despite advancements in cancer treatment, understanding the long-term mental health implications for nasopharyngeal carcinoma (NPC) survivors remains an underexplored area. This study aims to examine the prevalence of mental disorders and their correlations with age at diagnosis and time since diagnosis among NPC survivors. A total of 1872 NPC patients were surveyed from September 2020 to June 2021 in this cross-sectional survey. Logistic regression models were used to analyze the associations of age at diagnosis and time since NPC diagnosis with the risk of mental disorders. Additionally, the potential nonlinear trend between these factors was examined using restricted cubic splines. Analyses were conducted both overall and stratified by gender. Gender interaction was also examined. The prevalences of depression, anxiety, and sleep disorders were 32.4, 33.2, and 61.5%, respectively. Age at NPC diagnosis was significantly associated with an elevated risk of depression (adjusted OR (aOR): 1.75 for 30-39 years old; 2.33 for 50-59 years old; 2.59 for ≥60 years old) and sleep disorders (aOR: 2.41 for 40-49 years old; 1.95 for 50-59 years old; 2.26, for ≥60 years old), compared to patients diagnosed with NPC at age < 30 years. Conversely, the risk of depression, anxiety, and sleep disorders exhibited negative associations with the time since diagnosis, compared to patients <3 months. Notably, significant nonlinear associations were observed between time since diagnosis and the risk of depression, anxiety, and sleep disorders, which showed an initial increase, with the highest risk occurring at approximately 3.0 (ORmax: 2.7), 1.5 (ORmax: 2.1), and 4.0 (ORmax: 1.9) months since NPC diagnosis, followed by a gradual recovery to a lower risk level at around 12 months. No gender interactions were observed. The prevalence of mental disorders is notable among NPC survivors, showing a positive correlation with age at diagnosis while displaying a negative correlation with time since diagnosis, thus indicating the need for psychological support, especially within the initial several months following NPC diagnosis.

Association between uric acid to high-density lipoprotein cholesterol ratio and chronic kidney disease among Chinese middle-aged and older adults with abnormal glucose metabolism: a nationwide cohort study.

Previous research has demonstrated a correlation between uric acid to high-density lipoprotein cholesterol ratio (UHR) and chronic kidney disease (CKD), yet the evidence remains unclear in individuals with abnormal glucose metabolism. The objective of this research was to investigate the correlation between UHR and the occurrence of CKD, as well as the rapid kidney function decline among individuals aged over 45years with abnormal glucose metabolism, using data from the China Health and Retirement Longitudinal Study (CHARLS). This study employed K-means clustering to categorize individuals based on UHR control levels into four classes. Subsequently, multivariate logistic regression analyses were utilized to explore the relationships between UHR and the occurrence of CKD as well as rapid kidney function decline. To examine the potential nonlinear relationship, restricted cubic spline (RCS) analyses were employed. Subgroup analyses and various sensitivity analyses were applied to validate the reliability of the results. This study encompassed 3902 participants, all of whom had prediabetes or diabetes. In the fully adjusted logistic regression model assessing the risk of CKD development, the odds ratios (ORs) for Class 2, Class 3, and Class 4, versus Class 1, were 1.08 (0.71 to 1.67), 1.71 (1.06 to 2.77), and 2.13 (1.02 to 4.35), respectively. For every 1 standard deviation (SD) increase in cumulative UHR exposure, there was a 32% elevation in the risk of CKD incidence (OR: 1.32, 95% CI 1.12 to 1.56). RCS curves suggested a linear association between cumulative UHR (CumUHR) and CKD occurrence, but a nonlinear association with rapid renal function progression. Subgroup analysis indicated an interaction between age and UHR on the development of CKD. The application of multiple sensitivity analyses yielded consistent outcomes, suggesting the robustness of the findings. In individuals with abnormal glucose metabolism, suboptimal control of UHR signifies an elevated risk of rapid kidney function decline and the incidence of CKD in the future. Therefore, close monitoring of long-term variations in UHR can facilitate early identification of the risk for CKD development.

Antioxidants and the risk of metabolic dysfunction-associated steatotic liver disease: results of National Health and Nutrition Examination Survey and two-sample Mendelian randomization analyses.

The link between antioxidants and metabolic dysfunction-associated steatotic liver disease (MASLD) is a topic of considerable discussion in the field of observational studies, with the exact causal connections still being unclear. In this investigation, a cohort consisting of 17 061 participants from the National Health and Nutrition Examination Surveys was studied. Initially, a cross-sectional analysis was carried out to examine the relationship between the CDAI and MASLD. Further, Mendelian randomization (MR) was utilized to assess the possible causal links between antioxidant levels in the bloodstream and MASLD. The association between the CDAI and MASLD was found to be significant in the fully adjusted logistic regression model, showing an OR of 0.95 [95% confidence interval (CI): 0.94-0.97; P < 0.001]. The use of restricted cubic spline regression revealed no significant nonlinear association between the CDAI and the occurrence of MASLD ( Pnonlinearity = 0.321). Additionally, MR findings did not suggest any causal connections between circulating levels of various antioxidants and MASLD. These antioxidants included vitamin A (retinol) (IVW: OR: 0.67, 95% CI: 0.33-1.36, P = 0.272), vitamin C (ascorbate) (IVW: OR: 0.61, 95% CI: 0.34-1.09, P = 0.094), vitamin E (α-tocopherol) (IVW: OR: 0.55, 95% CI: 0.13-2.25, P = 0.407), vitamin E (γ-tocopherol) (IVW: OR: 0.89, 95% CI: 0.36-2.23, P = 0.806), zinc (IVW: OR: 0.95, 95% CI: 0.82-1.09, P = 0.449), selenium (IVW: OR: 0.98, 95% CI: 0.84-1.16, P = 0.855), and carotene (IVW: OR: 0.80, 95% CI: 0.36-1.81, P = 0.596). The findings highlight a significant negative linear relationship between CDAI and MASLD prevalence in the observational component of the study. However, the MR analysis did not indicate any causal effects of circulating antioxidant levels on MASLD.

Single and Joint Associations Between Blood Cell-Based Inflammatory Indicator in Early Pregnancy and Risk of Gestational Diabetes Mellitus (GDM): A Prospective Cohort Study.

This study aims to introduce the Bayesian kernel machine regression (BKMR) model to explore the single and joint associations between exposure to blood cell-based inflammatory in early pregnant women and gestational diabetes mellitus (GDM). The study included 536 singleton pregnant women from the Zunyi Birth Cohort. Logistic regression, restricted cubic spline regression, and BKMR were used to investigate single, nonlinear, and combined associations. In this study, the adjusted odds ratio (OR) of white blood cell (WBC), neutrophil (NEUT), monocyte (MONO), platelet (PLT), neutrophil-to-lymphocyte ratio (NLR), and systemic immune inflammation index (SII) were 2.20 (95% confidence interval [CI]: 1.43-3.37), 2.27 (95% CI: 1.48-3.48), 1.67 (95% CI: 1.09-2.57), 1.66 (95% CI: 1.07-2.58), 1.65 (95% CI: 1.08-2.54), and 1.89 (95% CI: 1.23-2.91), respectively. Nonlinear associations of WBC (cutoff level: 7.91×109/L) and NEUT (cutoff level: 5.52×109/L) with GDM were also observed. Furthermore, BKMR analysis showed that the risk of GDM was linked with increased levels of blood cell-based inflammatory indicators. In early pregnancy, multiple blood cell-based inflammatory indicators are significantly positively correlated with the risk of GDM. Specifically, WBC and NEUT counts exhibit the most prominent association with GDM risk. Therefore, more attention should be paid to the inflammation levels of early pregnant women.

Retrospective Study on the Association Between Climate Factors and Infant Colic in Beijing (2021-2022).

To assess seasonal variations in infant colic (IC) prevalence and explore the association between climate factors, including temperature, air pollutants, and their interactions, with IC. Medical records of 1955 infants aged 0-3 months from October 2021 to September 2022 were analyzed, with IC diagnosed according to Rome IV criteria. Seasonal differences in IC prevalence were compared using chi-square tests. Climate data, including weekly averages of temperature, PM2.5, PM10, NO2, CO, O3, and AQI, along with 1-, 2-, and 4-week lags, were collected via web scraping. Interaction terms between temperature and pollutants (including lagged variables) were created. Variance Inflation Factors (VIF) addressed multicollinearity. Pearson correlation assessed linear relationships, while Generalized Additive Models (GAM) evaluated non-linear associations. The overall IC prevalence was 38.62%. Demographic analysis showed no significant differences between infants with and without IC. Seasonal analysis revealed significant differences, with the highest IC prevalence in winter. After Bonferroni correction, spring (34.52%) and winter (43.60%) differed significantly (p < 0.0083). Linear correlation analysis indicated weak associations between temperature, pollutants, and their interactions with IC (correlation coefficients: -0.05 to 0.03). GAM confirmed these findings, with individual climate factors explaining only 0.002 of the deviance and their interactions explaining 0.007. No meaningful relationship between climate factors and IC prevalence was identified. This study identified significant seasonal differences in IC prevalence, with the highest rates observed in winter. However, no significant linear or non-linear associations were found between IC and temperature, air pollutants, or their interactions. These findings underscore the need for future research to explore non-climatic factors.

Association of daily physical activity and bone microarchitecture in young adults with type 1 diabetes — A pilot exploratory study

PurposePhysical activity (PA) is an important determinant of skeletal health. In young adults with type 1 diabetes (T1D) fracture risk is increased, yet few studies have examined the PA and bone health relationship. Therefore, this pilot cross-sectional study characterized PA levels and their association with bone parameters measured by high resolution peripheral quantitative computed tomography (HR-pQCT) in young adults with T1D. MethodsHR-pQCT (Xtreme CTII) was used to measure bone outcomes at the distal tibia and radius, and accelerometery (ActiGraph GT3X) recorded daily minutes of light and moderate-vigorous physical activity (MVPA). Quadratic regression analyses were conducted with a p-value ≤ 0.05 considered significant. ResultsPA data from 19 young adults (23.1 ± 1.9 years) with T1D was analyzed. Over half (63 %) of participants completed ≥150 min of MVPA per week, however, most measured activity time per day (57 %) was spent in sedentary pursuits. Significant non-linear associations were found between the duration of MVPA and several trabecular bone parameters at the tibia. ConclusionsIn young adults with T1D, MVPA may have site specific (tibia) and compartment specific (trabecular) non-linear associations with bone. Further studies should confirm these findings, which may help inform evidence-based exercise recommendations to optimize bone health in young adults with T1D.

Relationship of Neutrophil Percentage-to-Albumin Ratio With Stroke: Evidence From NHANES 1999-2020.

The objective of this research is to examine the association between neutrophil percentage-to-albumin ratio (NPAR) and stroke, providing a reference for the prevention and prognosis of clinical stroke. The study included 56,566 participants from the National Health and Nutrition Examination Survey (NHANES) to explore the association between NPAR and stroke using logistic regression and restricted cubic splines. Upon identifying the nonlinear relationship, inflection points were calculated using recursive algorithms and two-stage linear regression models. Stratified analyses and interaction tests examined variations across population groups. After adjusting for confounders, NPAR was positively associated with stroke (OR: 1.09, 95% CI: 1.05-1.12). Restricted cubic spline analysis indicated a nonlinear trend. Beyond the inflection point, the increasing trend of stroke incidence with higher NPAR levels began to slow down. This relationship remained nonlinear in males but was linear in females. This study revealed a nonlinear positive association between NPAR and stroke, with higher NPAR increasing the risk of stroke.

Correlation Between Thyroid Hormone and Controlled Attenuation Parameters: A Cross-Sectional Population-Based Study.

The aim of the present study was to investigate how thyroid hormone levels are related to controlled attenuation parameters (CAP), which may provide insights for understanding the role of these factors in hepatic steatosis. A total of 3461 participants who underwent CAP diagnosis between 2018 and 2023 were included. The associations between thyroid hormone levels and CAP were evaluated through multiple linear regression, restricted cubic splines (RCS) and threshold effect analyses. Multiple linear regression analysis revealed an inverse relationship between free thyroxine (FT4) and CAP, with a coefficient of -0.855 and a confidence interval of -1.297 to -0.412. The negative connection in a subset examination persisted in males [-0.729 (-1.295, -0.162)] and females [-1.234 (-1.996, -0.473)]. A strong correlation was found between free 3,5,3'-triiodothyronine (FT3) and CAP, with values of 2.182 (1.154, 3.211). Further analysis was conducted on both male [1.626 (0.188, 3.065)] and female [2.835 (1.137, 4.533)] subgroups. In the severe liver steatosis group, there was a significant negative correlation between FT3 and CAP based on the subgroup analysis stratified by the level of liver steatosis [-3.804 (-6.711, -0.898)]. The RCS analysis showed a nonlinear association between FT4 and CAP, with a turning point at 11.14 pmol/L. There was a significant linear and nonlinear relationship between FT4, FT3 and CAP. Thyroid hormones could have a significant impact on liver steatosis, offering fresh perspectives on how to prevent and treat this condition.

Association of weight-adjusted waist index (WWI) and a body shape index (ABSI) with serum neurofilament light chain levels in a national study of U.S. adults

ObjectiveThis study explored how the weight-adjusted waist index (WWI) and a body shape index (ABSI) are related to serum neurofilament light chain (sNfL) levels among U.S. adults. We aimed to evaluate sNfL, which plays key roles in neuronal injury in neurological diseases, given its understudied connection to obesity.MethodsWe used cross-sectional data from the 2013–2014 National Health and Nutrition Examination Survey (NHANES) of people with complete information on the weight-adjusted waist index (WWI), a body shape index (ABSI), and serum neurofilament light chain (sNfL). Multiple linear regression analysis allowed us to investigate the separate connections among the WWI, ABSI, and sNfL. Moreover, interaction testing and subgroup analysis were performed to improve the general validity of our results. To assess any nonlinear correlations, we also performed threshold effect analysis and smoothed curve fitting.ResultsWWI and ABSI were positively linked with sNfL (WWI: β = 0.05, 95% CI 0.01–0.09; ABSI: β = 1.65, 95% CI 3.53–13.72). There was no clear reliance on this association according to subgroup analysis and interaction tests. Smoothed curve fitting and saturation effects also demonstrated nonlinear associations between WWI and ABSI and sNfL, with inflection points of 10.38 and 0.38, respectively.ConclusionIn the adult American population, while the WWI and ABSI are linearly positively correlated with serum neurofilament light protein (sNfL), the effect size is greater for the ABSI. This correlation provides fresh evidence connecting obesity to neurological conditions, deepening our comprehension of the extensive health impacts associated with obesity.Level of Evidence Level I, experimental studies.

Utility of Anthropometric Indexes for Detecting Metabolic Syndrome in Resource-Limited Regions of Northwestern China: Cross-Sectional Study.

Anthropometric indexes offer a practical approach to identifying metabolic syndrome (MetS) and its components. However, there is a scarcity of research on anthropometric indexes tailored to predict MetS in populations from resource-limited regions. This study aimed to examine the association between 8 easy-to-collect anthropometric indexes and MetS, and determine the most appropriate indexes to identify the presence of MetS for adults in resource-limited areas. A total of 10,520 participants aged 18-85 years from Ningxia Hui Autonomous Region, China, were included in this cross-sectional study. Participants were recruited through a stratified sampling approach from January 1, 2020, to December 31, 2021. MetS was defined using the International Diabetes Federation (IDF) criteria. Eight anthropometric indexes were examined, including BMI, waist-to-height ratio (WHtR), weight-adjusted waist index (WWI), conicity index, a body shape index (ABSI), lipid accumulation products (LAP), visceral obesity index (VAI), and the triglyceride-glucose (TyG) index. Logistic regression analysis and restricted cubic splines (RCSs) were applied to identify the association between the anthropometric indexes. The receiver operating characteristic curve and the area under the curve (AUC) were analyzed to identify and compare the discriminative power of anthropometric indexes in identifying MetS. The Youden index was used to determine a range of optimal diagnostic thresholds. Logistic regression analysis was applied to identify the association between the anthropometric indexes. A total of 3324 (31.60%) participants were diagnosed with MetS. After adjusting for age, ethnicity, current residence, education level, habitual alcohol consumption, and tobacco use, all the 8 indexes were positively correlated with the risks of MetS (P<.05). LAP presented the highest adjusted odds ratios (adjOR 35.69, 95% CI 34.59-36.80), followed by WHtR (adjOR 29.27, 95% CI 28.00-30.55), conicity index (adjOR 11.58, 95% CI 10.95-12.22), TyG index (adjOR 5.53, 95% CI 5.07-6.04), BMI (adjOR 3.88, 95% CI 3.71-4.05), WWI (adjOR 3.23, 95% CI 3.02-3.46), VAI (adjOR 2.11, 95% CI 2.02-2.20), and ABSI (adjOR 1.71, 95% CI 1.62-1.80). Significantly nonlinear associations between the 8 indexes and the risk of MetS (all Pnonlinear<.001) were observed in the RCSs. WHtR was the strongest predictor of MetS for males (AUC 0.91, 95% CI 0.90-0.92; optimal cutoff 0.53). LAP were the strongest predictor of MetS for females (AUC 0.89, 95% CI 0.89-0.90; optimal cutoff 28.67). Statistical differences were present between WHtR and all other 7 anthropometric indexes among males and overall (all P<.05). In females, the AUC values between LAP and BMI, WWI, ABSI, conicity index, VAI, and TyG index were significantly different (P<.001). No statistical difference was observed between LAP and WHtR among females. According to 8 anthropometric and lipid-related indices, it is suggested that WHtR and LAP are the most appropriate indexes for identifying the presence of MetS in resource-limited areas.

Decoding the fatty liver-hyperuricemia link in the obese and nonobese hypertensive patients: insights from a cohort study

Metabolic-dysfunction-associated fatty liver disease (MAFLD) and serum uric acid are closely related to cardiovascular and cerebrovascular diseases. However, the causal association between MAFLD and serum uric acid remains unclear. A total of 3417 patients without hyperuricemia were included in the final analysis. MAFLD was defined as fatty liver index (FLI) ≥ 30. Multivariate Cox regression analysis was used to explore the association between FLI and new-onset hyperuricemia. Restricted cubic splines and threshold saturation effect analysis were used to detect nonlinear associations. The mean age was 62.8 ± 8.3 year, and 68.5% were women. A total of 738 (21.6%) hypertensive patients developed new-onset hyperuricemia, 388 (11.4%) new-onset hyperuricemia10 and 190 (5.6%) new-onset hyperuricemia20 during the 4-year midday follow-up period. In the fully adjusted model, compared with the Q1 (FLI ≤ 8.5) group, the risk of hyperuricemia increased by 56% (HR: 1.56; 95% CI: 1.02, 2.38) in the Q4 (FLI > 39.4) group, new-onset hyperuricemia10 increased by 108% (HR: 2.08; 95% CI: 1.15, 3.78), and new-onset hyperuricemia20 increased by 156% (HR: 2.56; 95% CI: 1.11, 5.94), respectively. Saturation effects showed a nonlinear association between FLI and new-onset hyperuricemia (p for log likelihood ratio test < 0.05). Subgroup analysis and stratified analysis showed that there had a significantly higher risk of new-onset hyperuricemia in the patients with normal body mass index (< 24 kg/m2) (p for interaction: 0.018) and non-central obesity (p for interaction: 0.024). MAFLD is an independent risk factor for hyperuricemia in hypertensive patients, especially in patients with normal body mass index and non-central obesity.

Association between adipose deposition and mortality among adults without major cardiovascular risk factors

AimTo examine the association between adiposity and mortality in U.S. adults without major cardiovascular risk factors. MethodsWe analyzed 7,948 adults (4,123 women, 3,825 men) aged > 20 years from the National Health and Nutrition Examination Survey (2003-2004, 2011-2016). Participants with cardiovascular disease, estimated glomerular filtration rate < 60 ml/min/1.73m², diabetes, hypertension, or pregnancy were excluded. Adiposity measures, assessed by dual-energy x-ray absorptiometry or anthropometrics, included android and gynoid fat mass index (FMI), android-to-gynoid ratio, subcutaneous, abdominal, and visceral FMI, BMI, and waist circumference. We employed multivariable-adjusted Cox regression and restricted cubic spline models to assess sex-specific associations between adiposity measures and all-cause mortality. ResultsOver a median follow-up of 7.8 years, there were 83 deaths among women and 119 among men. In women, BMI, waist circumference, and gynoid FMI showed non-linear associations with all-cause mortality, while in men, BMI, waist circumference, and android-to-gynoid ratio demonstrated similar non-linear associations. In final adjusted models, a 1-SD increase in visceral, subcutaneous, and abdominal FMI among women was associated with 61% (HR 1.61, 95% CI 1.17-2.21), 87% (HR 1.87, 95% CI 1.13-3.08), and 89% (HR 1.89, 95% CI 1.19-2.99) higher mortality risk, respectively. Women in the lowest tertile of gynoid FMI had an 82% (HR 1.82, 95% CI 1.01-3.29) higher mortality risk compared to those in the middle tertile. In final adjusted models, a 1-SD increase in gynoid, android, visceral, subcutaneous, and abdominal FMI among men was associated with 30% (HR 1.30, 95% CI 1.02-1.65), 41% (HR 1.41, 95% CI 1.09-1.83), 54% (HR 1.54, 95% CI 1.04-2.28), 69% (HR 1.69, 95% CI 1.25-2.29), and 76% (HR 1.76, 95% CI 1.25-2.48) higher mortality risk, respectively. Additionally, men in the middle tertile of android-to-gynoid ratio had a 2.68-fold higher mortality risk compared to the lowest tertile, while men in the highest BMI tertile had an 83% higher mortality risk compared to the lowest tertile. Sex modified the association between gynoid FMI and mortality (P-interaction = 0.008). ConclusionImaging-based adiposity measures have distinct prognostic value for mortality beyond traditional anthropometrics in adults without cardiovascular risk factors.

Vertical Living and Longevity: Examining Mortality by Floor of Residence in an Elderly Population.

Studies investigating the potential health effects of floor of residence have reported conflicting results. In the Rotterdam Study, we examined associations between floor and mortality among elderly residents of a neighborhood of Rotterdam, the Netherlands. Participants who were high-rise residents at baseline (n = 2330) were followed for 10years, until loss to follow-up or death (N = 602). Cox proportional hazard models revealed nonlinear association of floor of residence with mortality, albeit not statistically significant across all floor categories. Compared to floors 13 and above, adjusted hazard ratios [95% confidence interval] were: 1.31 [0.89-1.95] (floors 1-2), 1.52 [1.04-2.22] (floors 3-4), 1.07 [0.73-1.57] (floors 5-6), 1.12 [0.76-1.66] (floors 7-8), 1.45 [0.96-2.18] (floors 9-10), and 1.04 [0.69-1.58] (floors 11-12). In this prospective population-based cohort of elderly adults in Rotterdam, the Netherlands, a nonlinear association was observed between floor level of residence and mortality, with stronger associations observed at lower floors compared to the highest floors.