Curve Fitting Analysis Research Articles

Nonlinear association between liver fat content and lumbar bone mineral density in overweight and obese individuals: evidence from a large-scale health screening data in China.

The impact of fatty liver disease on lumbar bone mineral density (BMD) represents an intriguing area of study, particularly in light of established research linking obesity to bone metabolism. However, there remains limited investigation into the correlation between quantifying liver fat content (LFC) and lumbar BMD among overweight and obese populations, particularly within the Chinese demographic. This study aims to accurately quantify LFC and investigate its association with lumbar BMD in overweight or obese individuals. This cross-sectional study was conducted at the Health Management Center of Henan Provincial People's Hospital from January 2019 to February 2023, involving 6996 participants with a body mass index (BMI) of 24 kg/m² or higher. LFC and lumbar BMD were assessed using computed tomography. The study utilized one-way ANOVA, subgroup analysis, multifactor regression analysis, smooth curve fitting, and threshold and saturation effect analysis to explore the relationship between LFC and lumbar BMD. Furthermore, inflammatory cell analysis was included to investigate the potential mediating role of inflammatory cells in the association between LFC and lumbar BMD. After adjusting for confounding variables, multivariate regression analysis revealed a significant negative association between LFC and lumbar BMD (β = -0.323, 95% CI: -0.464 to -0.183, P < 0.001). Particularly, participants in the highest baseline LFC quartile (Q4 group) exhibited a more pronounced negative impact on lumbar BMD compared to those in the lowest quartile (Q1 group) (β = -5.026, 95% CI: -7.040 to -3.012, P < 0.001). Threshold saturation effect analysis identified a turning point in the LFC-BMD relationship (K = 5.4). Below this point, LFC showed a positive correlation with lumbar BMD (β = 0.962, 95% CI: 0.016-1.907, P < 0.05), whereas above it, LFC was significantly negatively correlated with lumbar BMD (β = -0.405, 95% CI: -0.558 to -0.253, P < 0.001). Additionally, mediation analysis indicated that leukocytes and monocytes potentially mediated the association between LFC and lumbar BMD, with mediation ratios of -5.78 and -6.68%, respectively. Among individuals categorized as overweight or obese, elevated levels of LFC were associated with reduced lumbar BMD, particularly noticeable above a threshold of 5.4%. Additionally, various types of inflammatory cells are presumed to exert a substantial mediating influence on the correlation between LFC and lumbar BMD.

Triglyceride glucose-waist circumference as a useful predictor for diabetes mellitus: a secondary retrospective analysis utilizing a Japanese cohort study

Background and objectiveWhile the connection between the Triglyceride glucose-waist circumference (TyG-WC) index and the risk of diabetes remains understudied, this particular research delves into the potential predictive value of the TyG-WC index within a significant Japanese population.MethodsThis retrospective cohort study encompassed a comprehensive analysis of 15,413 Japanese adults, all of whom were diabetes-free at the outset of the study period from 2004 to 2015. Comprehensive medical records were obtained for all participants who underwent physical examinations. The study employed Cox proportional-hazards regression, smooth curve fitting, various sensitivity, and subgroup analyses to explore the association between TyG-WC and the development of diabetes. Furthermore, a Receiver Operating Characteristic (ROC) curve was created to detect the predictive capability of TyG-WC for diabetes risk.ResultsAfter a maximum of 13.0 years of follow-up, 358 people finally developed diabetes. Upon adjusting for covariates, the result showed TyG-WC was positively and independently associated with incident Diabetes Mellitus (DM) (Hazard Ratio (HR): 1.004, 95%C: 1.001–1.006). Furthermore, ROC curve analysis demonstrated that TyG-WC outperformed both the triglycerides-glucose index and triglyceride glucose-body mass index in predicting the onset of diabetes.ConclusionHigh levels of TyG-WC are autonomously linked to a heightened risk of diabetes in the Japanese demographic, indicating its potential as a dependable predictive indicator for diabetes mellitus in individuals at elevated risk.

Association of anxiety status and anxiety duration with constipation in adult Americans: a cross-sectional study using data from the NHANES 2007–2010

BackgroundConstipated patients may exhibit anxious behaviors, but the relationship between the two remains unclear. This population-based study aims to investigate the relationships of anxiety status and anxiety duration with constipation among U.S. adults.MethodsUsing data from the National Health and Nutrition Examination Survey (NHANES) database spanning from 2007 to 2010, a cross-sectional study included 8945 participants was performed to assess the relationships of anxiety status and anxiety duration with constipation. Participants’ characteristics were presented using mean or proportion. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using multivariable logistic regression models. The analysis accounted for potential confounding factors, including gender, age, race/ethnicity, education level, marital status, PIR, BMI, smoking status, drinking status, chronic diseases, and dietary intake. Subgroup analyses were conducted to ensure the stability of the results. Smoothed curve fitting was applied to investigate both linear and nonlinear associations between anxiety duration and constipation risk. Threshold effects were assessed using two-piecewise linear regression models.ResultsOf the 8945 participants, 922 reported constipation, with a prevalence of 10.3%. After adjusting for confounding factors, individuals with anxiety status exhibited an increased risk of constipation (OR: 1.49, 95% CI: 1.28–1.73). Stratified analyses indicated that the association between anxiety status and constipation remained relatively stable across different stratification levels. Smoothed curve fitting and threshold effect analyses revealed a linear association between anxiety duration and constipation among adults aged 20–60, while a nonlinear inverted U-shaped relationship was observed in those aged 60 and older, with an inflection point at 10 days. The two variables correlated positively on the left side of the inflection point but not on the right.ConclusionThis study showed that a significant association between anxiety status and constipation among U.S. adults. Additionally, an age-dependent association between anxiety duration and constipation was observed, particularly among individuals aged 60 and older.

The nonlinear association between body roundness index and infertility in married women

Infertility is increasingly linked to obesity, especially visceral fat accumulation. The Body Roundness Index (BRI) provides a precise quantification of body and visceral fat but its implications for infertility risks and diagnostic value are yet to be fully determined. This study analyzed data from 1,305 married women aged 20–45 years, drawn from the National Health and Nutrition Examination Survey (NHANES). Logistic regression was utilized to examine the relationship between BRI and infertility, incorporating univariate and multivariate regression analyses, smooth curve fittings, and subgroup analyses. Additionally, Receiver Operating Characteristic (ROC) analysis assessed the predictive capability of BRI for infertility. An increase in one unit of BRI correlated with a 13% higher prevalence of infertility after adjusting for covariates (OR = 1.13; 95% CI: 1.05, 1.21). Women with higher BRI exhibited greater infertility odds compared to the reference group (OR: 2.20, 95% CI: 1.42, 3.42). Smooth curve fitting analysis revealed a positive, nonlinear relationship, with an inflection point observed at a BRI value of 7.95. Subgroup analyses upheld the robustness of this association across varied demographic segments. ROC curves indicated significant diagnostic potential of BRI in younger women, whereas its predictive relevance diminished in those over 35, akin to other obesity markers. This study is the first to rigorously affirm a strong link between increased BRI and the higher prevalence of infertility among married women aged 20–45. To optimize fertility, maintaining a healthy weight and waist circumference is recommended. The integration of BRI into clinical practice could assist in early intervention for women at risk of infertility. However, further research is required to identify effective predictive markers for infertility in women aged 36–45.

Association between cardiometabolic index and overactive bladder in adult American women: A cross-sectional study.

Overactive bladder (OAB) is a common disorder, particularly in women, and its symptoms, including urgency, frequency, and nocturia, can significantly affect quality of life. The cardiometabolic index (CMI) is a novel metabolic risk indicator that has been receiving more attention lately. This study investigated the association between CMI and OAB in adult women. A cross-sectional analysis was performed using data from the National Health and Nutrition Examination Survey (NHANES) covering the years 2007 to 2018, including 6323 female participants. CMI was calculated based on waist-to-height ratio, triglyceride, and HDL cholesterol levels, while OAB was assessed using the overactive bladder symptom score (OABSS). The association between CMI and OAB was evaluated through multivariate logistic regression, generalized additive models (GAM), smoothing curve fitting, and subgroup analysis. We finally included male participants for sensitivity analysis. A significant positive association was found between female CMI and OAB prevalence (OR = 1.46, 95% CI: 1.29-1.65). When compared to the lowest CMI quartile (Q1), women in the highest CMI quartile were 70% more likely to have OAB (OR = 1.70, 95% CI: 1.42-2.04). Smoothed curve fitting analysis showed a linear association between CMI and OAB. Subgroup analysis revealed that the association between CMI and OAB was stronger in women aged 20-50 years as well as in women without hypertension. Sensitivity analysis confirmed the robustness of our result. CMI was significantly and positively associated with the prevalence of OAB, especially in women aged 20-50 years without hypertension. This finding provides a new perspective on metabolic risk management and may contribute to the early prevention and improvement of bladder function in women.

Association between five novel anthropometric indices and erectile dysfunction in US adults from NHANES database

Erectile Dysfunction (ED) is the leading cause of sexual dysfunction affecting hundreds of millions of men worldwide, and has been described as an important public health problem. The association of five novel anthropometrics related to obesity, lipids and glucose with ED remains unclear. To investigate the association of lipid accumulation products index (LAP), triglyceride glucose index (TyG), waist triglyceride index (WTI), weight-adjusted-waist index (WWI) and a body shape index (ABSI) with ED. Cross-sectional data from the NHANES were used. Participants were adults aged 20–85 y from 2001 to 2004. The analysis of logistic regressions, smooth curve fitting, subgroup analyses and generalized addition model were performed to examine the relationship between five novel anthropometric indicators and the prevalence of ED. An overall 1413 adult men were included in the study. After adjusting for confounding factors, the results of multiple regression analysis showed, ED positively correlated with LAP(OR = 1.0031, P < 0.05), TyG(OR = 1.2981, P < 0.05), WTI(OR = 1.4220, P < 0.05), WWI(OR = 1.6043, P < 0.001), and ABSI(OR = 1.6211, P < 0.05). Smoothed curve fitting and subgroup analyses proved the stability of the relationship. This cross-sectional study showed a positive correlation between these five novel anthropometric indicators (LAP, TyG, WTI, WWI, ABSI) and ED. Further studies are needed to explore their association better and the underlying mechanisms.

Association between daily sitting time and sarcopenia in the US population: a cross-sectional study

BackgroundSarcopenia is an age-related syndrome marked by a gradual decline in skeletal muscle mass and function. While various factors influencing sarcopenia have been studied, the link between daily sedentary time and sarcopenia remains underexplored.MethodThis study analyzed the association between daily sitting time and sarcopenia using data from the National Health and Nutrition Examination Survey (NHANES 2011–2018). Daily sitting time was assessed through questionnaires, while sarcopenia was measured using body mass index (BMI) adjusted appendicular skeletal muscle mass (ASM). The relationship was analyzed using weighted logistic regression models and smoothing curves. Stratified analyses and interaction testing were employed to investigate population-specific characteristics of this association. Furthermore, chi-square test and grouped logistic regression were used to further analyze the impact of vigorous activity on the relationship between the two variables.ResultThis study included 9998 participants with complete information. The fully adjusted model showed a significant positive correlation between daily sitting time and the prevalence of sarcopenia (OR = 1.07, 95% CI: 1.03–1.10, P = 0.0026). The group with daily sitting time ≥ 9 h had a 90% higher risk of sarcopenia compared to the < 4 h group (OR = 1.90, 95% CI: 1.22–2.84, P = 0.0040). Smooth curve fitting analysis showed a linear correlation between this relationship. Stratified analysis shows that non-Hispanic white men with a lower BMI (BMI < 25) have a higher risk of sarcopenia. Compared to those who actively participate in vigorous activities, individuals who lack recreational activities have a higher prevalence and risk of sarcopenia.ConclusionOur research has found that increased sedentary time significantly increases the risk of sarcopenia, especially among non-Hispanic white men with lower BMI. Additionally, individuals who lack vigorous physical activity also have a higher prevalence and risk of sarcopenia. Therefore, reducing sedentary behavior and increasing moderate exercise may be effective prevention strategies.

Association of serum calcium level with periodontitis: a cross-sectional study from NHANES 2009-2014.

This study aimed to investigate the association between serum calcium levels and periodontitis in a U.S. adult population, using data from the National Health and Nutrition Examination Survey (NHANES) 2009-2014. Data were analyzed from 8,601 participants aged over 30 years, who were categorized based on the presence or absence of periodontitis. Serum calcium levels were measured using standardized NHANES protocols, and periodontitis status was determined through clinical oral examinations. To assess the relationship between calcium levels and periodontitis, multivariate logistic regression models were applied across three levels of adjustment. Additionally, trend tests and subgroup analyses were conducted to explore associations across different demographic and clinical subgroups. A smoothing curve fitting and threshold effect analysis were also performed to examine potential nonlinear relationships. After adjusting multiple covariates, participants in the highest quartile of serum calcium showed an 18% reduced risk of periodontitis compared to those in the lowest quartile (OR = 0.82, 95% CI: 0.71-0.95, p = 0.0083; p for trend = 0.0057). The association remained stable across various subgroups. Smoothing curve fitting indicated a nonlinear negative correlation between calcium levels and periodontitis, though without a significant inflection point at 2.48 mmol/L (p = 0.094). Elevated serum calcium levels appear to be associated with a lower risk of periodontitis in adults. These findings suggest that adequate calcium intake may play a role in periodontitis prevention, providing valuable insight for clinical guidance on nutritional and preventive strategies in periodontal health.

The relationship between non-HDL-C/HDL-C ratio and bone mineral density: an NHANES study.

The non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) is a newly developed lipid parameter. However, the current research has only explored the relationship with lumbar spine bone mineral density, lacking studies on bone mineral density at other sites, total body bone mineral density, and an analysis of risk factors. This study aims to determine the potential association between NHHR and lumbar BMD, increase awareness of the impact of lipid levels on bone health. By utilizing data from the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2018, we conducted univariate and generalized linear models (GLMs) analysis, stratified analysis, threshold effect analysis, smooth curve fitting and stratified analysis to investigate the association between NHHR and BMD. NHHR levels were categorized into tertiles (low, medium, and high) based on their distribution among the study population. The study included 8,671participants, studies have shown, the ratio of non-high-density lipoprotein to high-density lipoprotein (NHHR) exhibits a stratified correlation with bone mineral density (BMD). In the BMI subgroup, NHHR is significantly negatively correlated with BMD at multiple sites in the low-to-middle BMI group (BMI <25 kg/m2), while no significant correlation is found in the high BMI group (BMI ≥30 kg/m2). In the gender subgroup, NHHR has a more pronounced effect on male BMD, mainly reflected in the reduction of lumbar spine and total body BMD. In the age subgroup, the negative correlation between NHHR and BMD is strongest in the younger group (18-30 years), gradually weakening in the middle-aged (31-44 years) and older groups (45-59 years). Further analysis suggests that dyslipidemia may influence bone metabolism through pathways such as inflammation and oxidative stress. The effect of NHHR on bone mineral density (BMD) varies by BMI, gender, and age. This study suggests that controlling NHHR levels may be a potential intervention target for bone health management, particularly for individuals with low-to-middle BMI, males, and younger populations. These findings offer a new perspective on the relationship between lipid metabolism and bone metabolism and provide scientific evidence for the development of personalized osteoporosis prevention and treatment strategies.

HDL-C is inversely associated with the incidence of osteoarthritis among the USA: evidence from the NHANES program of 1999–2020

Osteoarthritis (OA) has been the most common arthritis affecting public health all over the world. Previous experimental research reported that increased low-density lipoprotein cholesterol, along with decreased high-density lipoprotein cholesterol may be associated with increased ectopic bone formation and possible knee OA, while clinical evidence is absent. This study aimed to investigate the association between blood high-density lipoprotein cholesterol (HDL-C) and OA. In this cross-sectional study, all the data were acquired from the National Health and Nutrition Examination Survey (NHANES) program from 1999 to 2020. The blood lipid metabolites of each participant were acquired from the laboratory data, using the standard approach. The diagnosis of OA was established through a questionnaire interview. The multivariate logistic regression analysis, subgroup analysis, and smooth curve fitting analysis were applied to investigate the association between the blood lipid metabolites and OA after adjusting with covariates including gender, age, race, BMI, marital status, physical activity, smoking, hypertension, and diabetes. The interaction analysis and Subgroup analysis were also performed. A total of 28,933 participants, including 3710 people with self-reported OA and 25,223 people without arthritis, were finally eligible for inclusion in this study. The multiple logistic regression indicated that in the 3rd and 4th quartiles, the HDL-C level showed a positive association with the risk of OA (Q3: OR = 1.1342, 95% CI 1.0071, 1.2773, p < 0.05; Q4: OR = 1.2354, 95% CI 1.0937, 1.3956, p < 0.001). The smooth curve fitting showed a trend that the OA odds ratio increased with the increase of HDL-C. Subgroup analysis continued to show that increased HDL led to increased OA risk at certain quartiles in different subgroups. This study shows a positive correlation between blood HDL-C levels and osteoarthritis (OA) risk, suggesting HDL-C may be a risk factor. Further research is needed, especially on lipid-lowering drugs like statins, which can affect HDL-C and influence this association.

Association between cardiometabolic index and all-cause and cause-specific mortality among the general population: NHANES 1999–2018

BackgroundCardiometabolic index (CMI) is a comprehensive clinical parameter which integrates overweight and abnormal lipid metabolism. However, its relationship with all-cause, cardiovascular disease (CVD), and cancer mortality is still obscure. Thus, a large-scale cohort study was conducted to illustrate the causal relation between CMI and CVD, cancer, and all-cause mortality among the common American population.MethodsOur research was performed on the basis of National Health and Nutrition Examination Survey (NHANES) database, involving 40,275 participants ranging from 1999 to 2018. The formula of CMI is [waist circumference (cm) / height (cm)] × [triglyceride (mg/dL) / high-density lipoprotein cholesterol (mg/dL)]. Outcome variables consisted of CVD, cancer, and all-cause mortality, which were identified by the International Classification of Diseases (ICD)-10. The correlation between CMI and mortality outcomes was analyzed utilizing the Kaplan–Meier survival modeling, univariate/multivariate Cox regression analysis, smooth curve fitting analysis, threshold effect analysis, and subgroup analysis. Stratification factors for subgroups included age, race/ethnicity, sex, smoking behavior, drinking behavior, BMI, hypertension, and diabetes.ResultsThe baseline characteristics table includes 4,569 all-cause-induced death cases, 1,113 CVD-induced death cases, and 1,066 cancer-induced death cases. Without adjustment for potential covariates, significantly positive causal correlation existed between CMI and all-cause mortality (HR = 1.03, 95% CI 1.02,1.04, P-value<0.05), CVD mortality (HR = 1.04, 95% CI 1.03, 1.05, P-value<0.05) and cancer mortality(HR = 1.03, 95% CI 1.02, 1.05, P-value<0.05); whereas, after confounding factors were completely adjusted, the relationship lost statistical significance in CMI subgroups (P for trend>0.05). Subgroup analysis found no specific subgroups. Under a fully adjusted model, a threshold effect analysis was performed combined with smooth curve fitting, and the findings suggested an L-shaped nonlinear association within CMI and all-cause mortality (the Inflection point was 0.98); in particular, when the baseline CMI was below 0.98, there existed a negative correlation with all-cause mortality with significance (HR 0.59, 95% CI 0.43, 0.82, P-value<0.05). A nonlinear relation was observed between CMI and CVD mortality. Whereas, the correlation between CMI and cancer mortality was linear.ConclusionsAmong the general American population, baseline CMI levels exhibited an L-shaped nonlinear relationship with all-cause mortality, and the threshold value was 0.98. What’s more, CMI may become an effective indicator for CVD, cancer, and all-cause mortality prediction. Further investigation is essential to confirm our findings.

Preliminary experiment on simulated human manual acupuncture of intelligent acupuncture robot based on Bama miniature pigs

To evaluate the performance of a newly developed intelligent acupuncture robot that simulates human manual acupuncture techniques through an animal experiment using miniature pigs. Two 3-month-old Bama miniature pigs were selected. One pig was used for the manual needling techniques of the practitioner, and the other pig was used for the intelligent acupuncture robot. The acupoints selected were "Qiangfeng" "Bojian" "Xiaokua" "Huiyang" (BL 35) and "Baihui" (GV 20), with a straight insertion depth of 25-35 mm. The manipulation techniques, including lifting-thrusting and twisting at a frequency of 90 times/min, were applied for 1 min, with 30 s each for lifting-thrusting (10 mm amplitude) and twisting (180° angle). The practitioner's needling techniques were captured using an optical motion capture system, and the collected data were input into the intelligent acupuncture robot for replication on the second miniature pig. A complete needling session of five acupoints was considered one round, and three rounds were performed per session, every other day, for a total of five sessions, completing 15 rounds. The Fréchet distance method was used to compare the robot's replicated needling data with the practitioner's data, and curve fitting analysis was conducted to evaluate the robot's performance and precision. The intelligent acupuncture robot achieved a total completion rate of 96.00% for 75 needling operations, with a non-completion rate of 4.00%. The robot's replication of the practitioner's needling techniques showed a good fit, with many characteristic points overlapping. The average Fréchet distance was 18.67. The Fréchet distance for the lifting-thrusting and twisting techniques at Baihui (GV 20) and "Huiyang" (BL 35) acupoints was smaller than that at "Xiaokua" and "Qiangfeng" points (P<0.01). The accuracy of the lifting-thrusting technique at "Xiaokua" and "Qiangfeng" acupoints was lower than the twisting technique (P<0.01). The intelligent acupuncture robot is able to replicate the pre-recorded manual needling parameters with a high degree of accuracy.

Auditory Temporal Processing Can Predict Reading Measurements in Neurotypical Adults: Evidence for Cascading Effects of Low-Level Auditory Processing on High-Level Cognitive Ability

ABSTRACT Accurate processing of auditory timing information has been proposed as crucial for the development of various complex cognitive abilities, such as literacy. However, empirical validation of this hypothesis has primarily involved using isochronous stimuli, which do not capture the nonlinearity inherent in the perception of timing in speech and music. Additionally, most work has focused on clinical/developmental populations and assessed timing at slower time scales, limiting our knowledge of this relationship. The current study introduces a perturbation stimulus design aimed at overcoming these limitations. We examined the association between reading abilities and behavioral entrainment to perturbation stimuli and applied a novel curve-fitting technique to analyze participants’ entrainment in response to perturbations. We demonstrate that behavioral entrainment during the post-perturbation time window yields superior predictive value across a wide array of reading measurements compared to entrainment to isochronous stimuli (before the perturbation) in a neurotypical adult population. Our perturbation paradigm effectively reveals individual differences in auditory temporal processing among neurotypical adults, offering a novel approach to investigating the link between auditory temporal processing and literacy skills beyond clinical/developmental contexts. Our novel curve-fitting analysis effectively captures the nonlinear aspects of participants’ entrainment when recovering from tempo perturbations.

Association between C-reactive protein-triglyceride glucose index and depressive symptoms in American adults: results from the NHANES 2005 to 2010

BackgroundThe novel serum C-reactive protein-triglyceride glucose index (CTI) has been identified as an ideal parameter that integrates inflammation and insulin resistance, which are potential mechanisms underlying depressive symptoms. Our research aimed to investigate the association between CTI and depressive symptoms.MethodsOur cross-sectional investigation utilized data from the National Health and Nutrition Examination Survey conducted between 2005 and 2010. The integrated CTI was calculated as 0.412 × Ln (C-reactive protein) (mg/dL) + Ln [triglyceride (mg/dL) × fasting glucose (mg/dL)/2]. The severity of depressive symptoms was evaluated through the continuous Patient Health Questionnaire-9 (PHQ-9) scores, and the categorical definition of depressive symptoms (PHQ-9 score ≥ 10) reflected moderate to severe symptoms. Survey-weighted linear and logistic regression models were conducted to establish the correlation between CTI and PHQ-9 scores, and between CTI and depressive symptoms. Moreover, subgroup analyses, interaction tests, and smoothed curve fitting were performed to scrutinize the steadiness of the results.ResultsA total of 5,954 participants were enrolled in our study, including 477 with depressive symptoms and 5,477 without. The results revealed a significant positive relationship between CTI and PHQ-9 scores (β: 0.40, 95% CI: 0.25,0.55, p < 0.001) and depressive symptoms (OR: 1.30, 95% CI: 1.06,1.61, p = 0.02). Additionally, individuals in the fourth quartile of CTI exhibited a higher likelihood of depressive symptoms than those in the first quartile (PHQ-9 score: β: 0.83, 95% CI: 0.39,1.26, p < 0.001; depressive symptoms: OR: 2.00, 95% CI:1.19,3.36, p = 0.01). Smooth curve fitting and subgroup analyses consistently demonstrated the positive relationship.ConclusionsElevated CTI was correlated with a higher risk of depressive symptoms, underscoring CTI as a potential clinical indicator for identifying and stratifying depressive symptoms.Clinical trial numberNot applicable.

The Role of Fibrinogen in Mediating NGAL-Associated Neuronal Damage in Acute Ischemic Stroke: A Moderated Mediation Analysis.

Both neutrophil gelatinase-associated lipocalin (NGAL) and fibrinogen are involved in the inflammation in acute ischemic stroke (AIS), but the interaction among them is unknown. Clarifying this issue will contribute to a better understanding of the mechanisms of injury in AIS. This study aimed to explore the association between NGAL, fibrinogen and neuronal damage in AIS. This study is a cross-section study. One hundred ninety-six successively hospitalized AIS patients in Renji Hospital in China between January 1, 2023, and May 31, 2023, were included. Circulating NGAL and fibrinogen were measured, and neuron-specific enolase (NSE) was detected to evaluate central neuronal damage. All data were analyzed by linear curve fitting analysis, multiple linear regression analysis, and moderated mediation analysis, respectively. There are linear relationships between log2-transformed NGAL, NSE, and fibrinogen, respectively. The β (95%) for the positive association between log2-transformed NGAL and NSE was 2.24 (1.15-3.32, p < 0.01), between log2-transformed NGAL and fibrinogen was 0.37 (0.19-0.56, p < 0.01), and between fibrinogen and NSE was 1.16 (0.48-1.85, p < 0.01) adjusting for potential confounders. These associations remained consistent in sensitivity analysis and hierarchical analysis. Increased fibrinogen significantly (p < 0.01) mediated 14.28% of log2-transformed NGAL-associated increased NSE risk. The NGAL levels were associated with NSE, and the NGAL-associated neuronal damage might be partially mediated by fibrinogen, suggesting that the inflammatory response among NGAL, fibrinogen, and NSE should be intervened to reduce neuronal damage after ischemic stroke. Further animal experiments are needed to clarify their specific mechanisms and precise relationships.

How much should the resting heart rate be controlled in patients with atrial fibrillation and coronary heart disease?

BackgroundCurrent guidelines recommend maintaining a resting heart rate below 100–110 beats per minute (bpm) for patients with atrial fibrillation (AF). However, there is a lack of research on various treatment approaches for patients with both atrial fibrillation and coronary heart disease (AF&CHD). We have discussed the primary therapeutic options for controlling resting heart rate in patients with AF&CHD.MethodsWe conducted a post hoc analysis of the AFFIRM (Atrial Fibrillation Follow-up Investigation of Rhythm Management) trial. Our study included 3986(98.2%) participants with AF, of which 1522 had AF&CHD. The primary outcome was all-cause mortality. We utilized the chi-squared test to identify significant differences in categorical variables. Multivariate Cox regression analysis was performed to compare the risk of death by standard deviation of heart rate visit to visit variability quartile.ResultsCompared to the AF group, a higher proportion of patients in the AF&CHD group had histories of smoking, hypertension, diabetes, heart failure, cardiomyopathy, valvular heart disease, peripheral vascular disease, bradycardia, hepatic or renal disease, pulmonary disease, and stroke (all P < 0.001). Additionally, patients with AF&CHD were more likely to undergo coronary artery bypass grafting (CABG) and pacemaker surgeries than those with AF alone. After adjusting for multiple clinical variables, patients with AF&CHD had a significantly higher risk of all-cause mortality compared to the AF group (RR = 1.79, 95% CI: 1.49–2.60; P < 0.01). Nonlinear multivariate curve-fitting analysis identified an optimal resting heart rate of 70 bpm for patients with AF&CHD (P < 0.001). Subgroup analysis revealed that patients with a resting heart rate below 70 bpm had lower all-cause mortality than those with a resting heart rate above 70 bpm (P < 0.001).ConclusionsFor resting heart rates below 70 bpm, our results suggest an inverse causal relationship between genetically determined resting heart rate and all-cause mortality in patients with AF&CHD.Clinical trial numberNot applicable.

A nonlinear relationship between alcohol consumption and cognitive function in elderly people: a population-based study from NHANES 2011-2014.

This study aims to explore the association between alcohol intake and cognitive function in elderly Americans, including potential nonlinear relationships and interactions across different subgroups. The study analyzed data from the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2014. The sample included 2,675 Americans aged 60 or older. Multivariate regression analysis was used to evaluate the relationship between alcohol intake and cognitive function. Smooth curve fitting and threshold effect analysis were employed to explore potential nonlinear relationships. Subgroup analyses were conducted to examine the stability of the results across different subgroups. The results indicate a significant negative correlation between alcohol intake and cognitive function. In the CERAD total word recall test, for every unit increase in alcohol intake, the score decreased by 0.15 points (-0.15, 95% CI: -0.25, -0.04), and in the CERAD delayed recall test, it decreased by 0.07 points (-0.07, 95% CI: -0.12, -0.01). Compared to Non-Heavy Drinkers, Heavy Drinkers showed a reduction in their CERAD total word recall scores by-0.77 points (-0.77, 95% CI: -1.23, -0.32) and in their CERAD delayed recall scores by-0.28 points (-0.28, 95% CI: -0.52, -0.04). Smooth curve fitting analysis revealed a nonlinear relationship between alcohol intake and cognitive function, with breakpoints at 10.7 for the CERAD total word recall test, 4.7 for the Animal fluency test, and 3.85 for the Digit symbol substitution test. Additionally, subgroup analysis indicated that gender, educational level, and smoking status significantly moderated the relationship between alcohol intake and cognitive function, while marital status, race, hypertension, diabetes, and cancer status showed no significant interactions. The association between alcohol intake and cognitive function in the elderly is complex, influenced by both the amount of intake and individual subgroup characteristics.

Preoperative D‑dimer level and prognosis in patients diagnosed with gastric cancer and undergoing gastric cancer radical surgery: A retrospective cohort study.

Gastric cancer, one of the most aggressive tumors affecting the digestive tract, has seen a rise in both incidence and mortality rates in recent years, with a lack of clear prognostic indicators. D-dimer, a byproduct of fibrin degradation, is a conventional coagulation biomarker that has been investigated as a potential adverse prognostic factor for postoperative cancer patients. However, conflicting results exist, with some studies suggesting that D-dimer is an independent risk factor for the postoperative prognosis of gastric cancer, and others suggesting that there is no significant association between D-dimer level and gastric cancer prognosis. This controversy underscores the need for further research to determine the true influence of D-dimer level on the prognosis of postoperative cancer patients, including exploring the linear and non-linear associations, and identifying optimal critical values before surgery. The present study aimed to assess the association between preoperative D-dimer levels and 5-year overall survival (OS) rate in patients undergoing radical surgery for gastric cancer. Data was analyzed from patients diagnosed with gastric cancer who underwent a radical gastrectomy at Shanxi Cancer Hospital (Taiyuan, China) in 2017 and were followed up for 5 years until December 2022. Preoperative D-dimer levels and tumor-related indicators were collected as covariates from hospital records, with patient follow-up information obtained from the hospital's tracking system. Utilizing multivariate Cox regression, curve fitting and inflection point analysis, the present study sought to investigate the link between preoperative D-dimer levels and 5-year OS rate following radical surgery for gastric cancer. After strict admission and exclusion procedures, a total of 133 patients were included in the study and were then classified based on D-dimer level. Based on the mean value, the D-dimer levels were segregated into two distinct cohorts: The D-dimer_high group (n=66) and the D-dimer_low group (n=67). Cox multiple regression analysis was conducted using both continuous and binary variables. The results showed no effect in terms of the continuous variables, but higher preoperative D-dimer levels were significantly associated with a higher 5-year overall survival compared with lower preoperative D-dimer levels in the categorical variables. Therefore, curve fitting was performed, which indicated that the association between D-dimer level and 5-year survival rate after radical gastrectomy for cancer showed a U-shaped curve, with P<0.001, high and low D-dimer levels both indicated poorer prognosis. A curvilinear correlation was demonstrated between preoperative D-dimer levels and the 5-year survival rate following radical gastrectomy for cancer. Subsequently, an inflection point analysis found that the inflection point was located at 100-200 ng/ml. In conclusion, in patients undergoing radical gastrectomy for gastric cancer, preoperative D-dimer can be used to indicate the current state of the tumor to some extent through blood coagulation status. Notably, a U-shaped association exists between D-dimer levels and 5-year postoperative survival rate in gastric cancer. This association demonstrates varying effects across different intervals. Specifically, D-dimer levels <100 ng/ml are associated with a worse prognosis, whereas levels >200 ng/ml are associated with a better prognosis.

Association of Body Roundness Index and A Body Shape Index with Obstructive Sleep Apnea: insights from NHANES 2015-2018 data.

This study examines the relationship between several anthropometric indices-Body Roundness Index (BRI), A Body Shape Index (ABSI), Waist-to-Weight Index (WWI), Waist Circumference (WC), and Body Mass Index (BMI)-and the prevalence of Obstructive Sleep Apnea (OSA) using data from the National Health and Nutrition Examination Survey (NHANES) spanning 2015 to 2018. A retrospective cross-sectional analysis of 7,004 adult participants was conducted using NHANES 2015-2018 data. Multivariable-adjusted logistic regression models were employed to assess the association between BRI, ABSI, and OSA. Non-linear relationships were explored via smooth curve fitting and threshold effect analysis using a two-part linear regression model. Subgroup analyses identified sensitive populations, and the discriminatory power of the indices in screening OSA was assessed using Receiver Operating Characteristic (ROC) curves. The analysis revealed a significant positive association between BRI and OSA, with a threshold effect observed at a BRI of 4.3. Below this threshold, OSA risk increased with higher BRI; however, no significant association was found above this threshold. Similarly, ABSI demonstrated a threshold effect at 8.2, with OSA risk positively associated to the left and negatively associated to the right. Subgroup analyses indicated stronger associations in younger and non-diabetic populations. ROC analysis identified BRI as a promising predictive tool for OSA, with an AUC of 0.64 (95% CI: 0.62-0.65). BRI demonstrates significant potential as a predictive index for OSA incidence, warranting further large-scale prospective studies to validate these findings.

Association between serum unsaturated fatty acids levels and infertility among American women from the National Health and Nutrition Examination Survey 2013–2014

BackgroundSome research indicates that unsaturated fatty acids (UFAs) in the diet could enhance reproductive outcomes in infertile women. However, other research holds different views, possibly due to differences in the conversion rates of UFAs from various foods and bioavailability in the body. Therefore, this research examined the link between serum UFAs and infertility issues.MethodsThis research included reproductive-age women participating in the 2013–2014 American National Health and Nutrition Examination Survey (NHANES). Serum levels of four UFAs, including palmitoleic acid (16:1n-7), vaccenic acid (18:1n-7), oleic acid (18:1n-9), and linoleic acid (18:2n-6) were measured through gas chromatography-mass spectrometry. Infertility data was collected by affirmative responses to targeted questionnaire items. Associations between serum UFA levels and infertility were evaluated utilizing Poisson regression models and smooth curve fitting methods. Sensitivity analysis was also conducted.ResultsThis study included 535 women, aged between 18 and 45. Poisson regression analysis, both adjusted and unadjusted for confounders, revealed no associations between palmitoleic acid, vaccenic acid, oleic acid, or linoleic acid and female infertility (all P > 0.05). However, four UFAs all showed non-linear relationships with infertility in smooth curve fitting analysis. Sensitivity analysis confirmed the stability of the findings.ConclusionThis research established non-linear associations between serum UFAs and infertility in American women. Specifically, maintaining appropriate serum levels of these UFAs may lower infertility risk. These findings offer new insights and practical dietary recommendations for improving female fertility.