Nonlinear Association Research Articles

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.

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

Some 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. This 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. This 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. This 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.

Nonlinear association between lung needle path CT attenuation values and postprocedural immediate pneumothorax following computed tomography-guided lung biopsy: a retrospective cohort study.

Pneumothorax is a potential complication following computed tomography-guided lung biopsy (CT-LB). However, the relationship between the lung needle path CT attenuation values and risk of post-procedural immediate pneumothorax remains unclear. The study aims to investigate this relationship. The present single-center retrospective cohort study analyzed the data obtained from 453 patients who underwent CT-LB from 2019 to 2022. The relationship between the lung needle path CT attenuation values and post-procedural immediate pneumothorax was assessed using restricted cubic splines, which were adjusted for potential confounders, and validated using linear and nonlinear binomial logistic models. A total of 453 patients (mean age: 60.2 ± 12.0 years old, 217 male patients) were evaluated. The incidence of post-procedural immediate pneumothorax was 41.06% (186/453). The median needle path CT attenuation was - 831 Hounsfield units (Hu). The linear models indicated an unstable association between lung needle path CT attenuation and post-procedural immediate pneumothorax (odds ratio: 0.99, 95% confidence interval: 0.99-1.00). The nonlinear analysis identified an inflection point at a CT attenuation value of -805 Hu. A stronger negative link was identified for needle path CT attenuation values below - 805 Hu (odds ratio: 0.99, 95% confidence interval: 0.98-0.99) between the needle path CT attenuation value and pneumothorax, while no statistically significant association was identified between these when the CT attenuation value was above - 805 Hu. There is a nonlinear association between the lung needle path CT attenuation values and risk of post-procedural immediate pneumothorax. For CT attenuation values below - 805 Hu, increasing the needle path CT attenuation values might reduce the risk of pneumothorax.

Association between sick child facility readiness and quality of care at the individual and facility level in five low- and middle-income countries.

Raising the quality of health services is key to continued progress in improving child health, however, data on service quality are limited and difficult to interpret. The relationship between facility readiness and the quality of care is complex. Using publicly available data sets from five low- and middle-income countries (LMICs), we assessed the relationship between structural factors and the clinical quality of care for managing sick children. We developed indices for readiness and quality accounting for available indicators, expert opinion, and alignment with integrated management of childhood illness (IMCI) guidelines. In each country, we assessed the association between readiness and quality, with and without adjusting for other factors. We considered associations overall, by domain, and by provider type, explored non-linear associations, and compared associations at the individual and facility-level. The analysis included data from 3,149 health facilities and 11,159 sick child observations. In four of the five countries included in the analysis, we observed for every 10%-point increase in readiness, quality increased by about 1% point after adjusting for facility type and managing authority. There was little evidence of a non-linear relationship or a threshold effect altering the relationship between readiness and quality of care. Beyond readiness, younger child age, higher cost of care, and having a respiratory, digestive, or febrile diagnosis were most often associated with a higher quality of care. Higher "human resources" readiness domain scores were most consistently associated with better quality of care, while the quality of care domain of "treatment" was the least influenced by readiness. Facility-level associations did not vary greatly from individual-level associations. The weak correlation observed suggests readiness plays an important role in quality but as currently measured cannot be used to characterize clinical quality of care. Data for assessing quality of health services are limited, presenting challenges for understanding impediments, assessing interventions, and gauging changes in the quality of care over time. We need better data to assess the quality of care being delivered in LMICs to understand what factors drive quality, with the goal of improving the management of sick children.

J-shaped association of serum uric acid with all-cause and cardiovascular mortality in patients with diabetic kidney disease.

The association of serum uric acid (SUA) with mortality remains unclear in patients with diabetic kidney disease (DKD). Thus, this prospective cohort study aimed to explore the association of SUA with all-cause and cardiovascular disease (CVD) mortality among patients with DKD in a large, nationally representative sample. This cohort study included data from the National Health and Nutrition Examination Survey (NHANES) 1999-2018 and the National Death Index mortality data until 31 December 2019. The restricted cubic spline and the Cox proportional hazards regression were conducted to describe the association of SUA with all-cause and CVD mortality and evaluate potential nonlinear associations. The analysis included 3470 patients with DKD from NHANES 1999-2018. During the follow-up time of 24,633 person-years, we recorded 1489 all-cause deaths, including 542 CVD deaths. We identified a J-shaped association of SUA with all-cause and CVD mortality. The corresponding inflection points were observed at 5.1 and 5.7mg/dL. When SUA were higher than inflection points, each 1mg/dL increase in SUA was linked to a 13% and 22% higher risk of all-cause (HR: 1.13; 95% CI: 1.07-1.20;P < 0.001) and CVD (HR: 1.22; 95% CI: 1.06-1.41;P = 0.006) mortality, respectively. This study indicated the J-shaped association of SUA with all-cause and CVD mortality in patients with DKD. The corresponding inflection points were 5.1 mg/dL for all causes and 5.7mg/dL for CVD, respectively. More clinical randomized trials are needed to confirm the optimal uric acid-lowering target.

The nonlineard association between triglyceride to HDL cholesterol ratio and long-term heart disease risk: findings from China Health and Retirement Longitudinal Study (CHARLS).

The aim of this study was to investigate the relationship between triglyceride to high-density lipoprotein cholesterol ratio (TG/HDL-C) and the risk of cardiovascular disease (CVD) in middle-aged and elderly Chinese population. CVD has high morbidity and mortality in China, with 5.09million CVD deaths in 2019 and a mortality rate of 364.5 cases per 100,000 people. Existing studies have focused on specific populations and lack studies on the general population. This study used data from the China Health and Aged Care Tracking Survey (CHARLS) to analyse the middle-aged and elderly population between 2011 and 2020. The exposure variable was TG/HDL-C ratio, the outcome variable was the occurrence of heart disease (including myocardial infarction, coronary heart disease, etc.), and the covariates included age, gender, education level, and body mass index. The final sample size was 4,551 participants. Weighted Cox regression models were used to assess the association between TG/HDL-C and CVD risk, and nonlinear associations and stratified analyses were performed. The results demonstrated a significant association between TG/HDL-C ratios and cardiac morbidity, with a risk ratio of 0.71 (95% CI: 0.71-0.71) in the adjusted model II. Nonlinear analysis revealed a threshold effect. Within the TG/HDL-C 0.15-1.5 interval (inflection point LnTG/HDL-C 0.41), each 1-unit increase in Ln (TG/HDL-C) was associated with a 17% reduction in the risk. The inflection point was associated with a 0.83-fold reduction in the risk of CVD (95% CI: 0.75, 0.92; p = 0.0003), but beyond this point, the association was no longer significant (1.00-fold reduction in risk; 95% CI: 0.95, 1.05; p = 0.9701). In contrast, stratified analyses demonstrated that the results were more applicable to women and those younger than 65 years. In summary, the study found a significant inverse relationship between the triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio and the risk of cardiovascular disease in the middle-aged and elderly Chinese population, with a nonlinear threshold effect observed at a TG/HDL-C ratio of around 1.5.

Informatics-based design of polyaniline-carbon nanotube thermoelectric nanocomposite using ANN and GA

Abstract Conducting polymer and carbon nanotube (CNT) based nanocomposites have emerged as prospective thermoelectric (TE) materials due to their potential application in flexible electronics. Non-conventional charge and heat transport in these nanocomposites, presents the possibility to enhance the TE conversion efficiency, given by Z T . However, the highly non-linear and complex association of structure and composition with the overall TE properties have hindered the development of any general strategy to develop high Z T nanocomposites. Here, we implement artificial neural network and genetic algorithm to develop data driven models followed by optimization to design high efficiency nanocomposites based on CNT dispersed in polyaniline (PANI) matrix. Our models suggest that CNT concentration plays the most crucial role in determining Z T . Non-dominated Pareto optimal solutions consisting of different combinations of design variables are obtained by multi-objective optimization. Although a range of optimal solutions span over different regions of the search space, in general we note that longer CNTs boost Seebeck coefficient ( S ) and electrical conductivity ( σ ) , and smaller length lowers thermal conductivity ( k ), while higher diameter of CNTs increase S and lowers σ and k . The results provide a general guideline for developing CNT-PANI nanocomposites with enhanced TE figure of merit.

Association between inflammatory markers and anemia in patients with diabetic foot ulcer.

Aim: Anemia of inflammation (AI) is common among patients with diabetic foot ulcers (DFU). This study aimed to investigate the specific relationship between inflammation indicators and anemia in patients with DFU.Materials & methods: This cross-sectional study was carried out among patients with DFU between 2018 and 2023. Clinical data were gathered before treatment. Restricted cubic spline regression was employed to investigate the non-linear associations between inflammation and anemia.Results: A total of 395 patients with Wagner grades 2-4 were enrolled in the study. About 63.54% of the patients with DFU had anemia which was primarily presented with normocytic hypopigmentation anemia. Elevated IL-6 levels (39.10-369pg/ml) were significantly associated with an increased likelihood of anemia (OR=4.84; 95% CI: 1.97-11.90). Similarly, high CRP levels (48.56-385mg/l) were linked to a higher prevalence of anemia (OR=5.01; 95% CI: 2.35-10.68). Furthermore, a nonlinear relationship was observed between CRP levels and anemia, suggesting that CRP values exceeding 53.889mg/l may trigger anemia in patients with diabetic foot ulcers.Conclusion: Inflammation is identified as an independent risk factor for AI in patients with DFU. The inflammation indicators (CRP and IL-6) and anemia exhibit an L-shaped nonlinear correlation in patients with DFU.

Abstract 4125581: Association Between Life’s Essential 8 and Premature Atherosclerotic Cardiovascular Disease: A Cross-sectional Study Among Young Adults in the United States

Background: Among patients presenting with atherosclerotic cardiovascular disease (ASCVD), the proportion of young individuals has increased in recent years. Life’s Essential 8 (LE8), containing two domains of health behaviors and health factors, is an updated monitoring measurement of cardiovascular health by assessing 8 modifiable risk factors. Objective: The objective of this study is to investigate the potential relationship between the LE8 score and a history of premature ASCVD among young adults residing in the United States. Methods: This population-based cross-sectional study utilized data from the National Health and Nutrition Examination Survey spanning 2005 to 2018, focusing specifically on adults aged 20 to 45. LE8 score was measured and categorized into low (0-49), moderate (50-79), and high (80-100) levels (Figure 1). Premature ASCVD status was determined by interviews conducted at enrollment, encompassing a self-reported composite disease history of coronary heart disease, angina pectoris, heart attack, and stroke. Following descriptive statistics, weighted multivariable logistic regression and restricted cubic spline models were employed to evaluate the associations between the LE8 score and premature ASCVD. Additionally, subscale and subgroup analysis were developed. Results: Among 17,499 participants, 9846 were eligible for analysis (weighted mean age, 32.7 years; male, 50.3%), and 167 had premature ASCVD history (weighted percentage, 1.46%). The weighted mean LE8 score of the study population was 71.99 (0.3). Following the adjustment for potential confounders, individuals with higher LE8 scores exhibited a reduced risk of developing premature ASCVD (Table 1). A nonlinear relationship was observed and similar patterns were also identified in the association of health behaviors and health factors scores with premature ASCVD (Figure 2). This inverse association was consistently observed across various subgroups, including sex, age strata, ethnicity, education, and income levels, with no significant interactions identified. Conclusions: The LE8 score and its subscale scores exhibited a negative, nonlinear association with premature ASCVD. Maintaining a healthy lifestyle and controlling modifiable risk factors are crucial in preventing premature ASCVD in the younger demographic. Further studies, encompassing prospective cohorts, are needed to confirm this finding.

Total, dietary, and supplemental calcium intake and risk of all-cause, cardiovascular, and cancer mortality among U.S. adults: a prospective cohort study from the National Health and Nutrition Examination Survey.

The study aimed to investigate the association of total, dietary, or supplemental calcium intake with all-cause, cardiovascular, and cancer mortality in American adults. This prospective cohort study used the National Health and Nutrition Examination Survey from 2005 to 2018. Participants were categorized into tertiles based on calcium intake. Risks of all-cause, cancer, or cardiovascular mortality and the dose-response relationship were estimated using weighted Cox proportional hazard regression and restricted cubic splines, with adjustments for demographic characteristics, comorbidities, laboratory parameters, and dietary data. In total, 6172 participants were included (median age: 61 years), and 869 had died (CVD:217, cancer:224) during a median follow-up of 81 months. After adjusting for confounders, higher total calcium(≥ 1660mg/d) [HR, 95%CI: 0.867 (0.865-0.869)], dietary calcium(≥ 1075mg/d) [HR, 95%CI: 0.711 (0.709-0.713)], and supplemental calcium (≥ 600mg/d) [HR, 95%CI: 0.786 (0.784-0.787)] intake groups were associated with lower all-cause mortality risk compared to the lowest intake group. Similar beneficial associations were found for cardiovascular, cancer mortality, and across subgroups of various ages, genders, races and body mass indexes. In the dose-response analysis, a 'J-shaped' nonlinear relationship was observed between calcium intake and the risk of all-cause, cardiovascular, and cancer mortality. Higher levels of total, dietary, or supplemental calcium were associated with lower all-cause, cardiovascular, or cancer mortality. However, a nonlinear association between calcium intake and mortality suggested that excessive calcium intake beyond a certain threshold may increase mortality risk.

Association Between Daily Internet Use and Intrinsic Capacity Among Middle-Aged and Older Adults in China: Large Prospective Cohort Study.

Intrinsic capacity (IC), as a comprehensive measure of an individual's functional ability, has gained prominence in the framework for healthy aging introduced by the World Health Organization (WHO). As internet usage continues to integrate into daily life, it is imperative to scrutinize the association between internet use and IC to effectively promote healthy aging among the middle-aged and older population. This study aimed to investigate whether daily internet use in middle-aged and older adults delays or accelerates the decline in IC. Participants included in the China Health and Retirement Longitudinal Study (CHARLS) comprised individuals aged ≥45 years residing in China. We analyzed 4 years of CHARLS data from the first wave (May 2011-March 2012) to the third wave (July 2015-January 2016). Data from the first and third waves were used for longitudinal studies. Self-reported data encompassed internet use, frequency of use, and demographic baseline characteristics. In addition, the IC evaluation involved physical examination and blood test data. Initially, linear regression was used to assess the relationship between daily internet use and IC, followed by regression splines to explore potential nonlinear associations. Subgroup and sensitivity analyses were used to investigate the heterogeneity of IC in specific conditions and the robustness of our results. Mediation effect analysis was conducted to identify the factors that mediate the relationship between daily internet use and IC, focusing on social participation, physical activity, and health status. Among the 12,826 participants included in the longitudinal analyses, 12,305 (95.9%) did not use the internet, while 521 (4.1%) reported daily internet use with a mean age of 52.62 (SD 7.67) years. After adjusting for demographic variables, socioeconomic factors, lifestyle behaviors, and health conditions and examining the impact of daily internet use and frequency on changes in IC, our findings indicated important associations. Specifically, daily internet use is significantly linked to a slower decline in IC over time (marginal effect 1.58, 95% CI 1.03-2.12; P<.001). Individuals with moderate and regular internet use frequency exhibit higher levels of maintenance in IC (marginal effect 0.74, 95% CI 0.45-1.03, P<.001). In addition, the relationship between IC changes and internet use frequency demonstrated a nonlinear inverted U-shaped curve (nonlinear P=.003). Subgroup analysis further revealed that improvements in IC vary based on age and gender. Furthermore, mediation analysis denoted that more than 28.78% (95% CI 21.24-40.33) of the observed association is mediated by social participation (P<.001). The findings of our research underscore the potential benefits of consistent and moderate internet use in promoting and preserving IC, particularly in cognitive capacity, sensory, vitality, and locomotion. The observed effects may be related to social participation. These insights offer valuable guidance for crafting strategies aimed at fostering healthy aging within the middle-aged and older adult demographics.

Triglyceride to high-density lipoprotein cholesterol ratio is associated with diabetes incidence in non-obese individuals with normoglycemia: a retrospective cohort study based on individuals from East Asia

BackgroundAlthough several studies have explored the association between the triglyceride to high-density lipoprotein cholesterol ratio (TG/HDL-c) and diabetes risk, most of these studies are cross-sectional and typically involve small sample sizes, limiting the ability to draw causal inferences. Additionally, there is currently a few studies specifically focusing on non-obese individuals. Consequently, we conducted a retrospective cohort study to investigate the impact of TG/HDL-c on the risk of developing diabetes among non-obese, normoglycemic individuals across East Asian countries.MethodsThis secondary retrospective cohort study recruited 85,029 non-obese individuals with normal glycemic levels from East Asian countries (China and Japan). We employed Cox proportional hazards regression models, incorporating cubic splines function for smooth curve fitting and using two-piecewise Cox regression for threshold effect analysis, to evaluate the nonlinear associations between baseline TG/HDL-c ratios and diabetes risk in non-obese individuals with normoglycemia. In addition, A range of subgroup and sensitivity analyses were performed to confirm the robustness of our results.ResultsAmong the individuals included, the average age was 42.14 ± 11.88 years, and 37,944 participants (44.62%) were male. After adjusting for covariates, the study revealed a significant correlation between the TG/HDL-c ratio and the risk of diabetes among non-obese individuals (HR=1.37, 95%CI: 1.22-1.54). Furthermore, a non-linear correlation was observed between the TG/HDL-c ratios and the incidence of non-obese diabetes, with an inflection point of 1.36. Under this threshold, the TG/HDL-c ratio notably boosts diabetes risk in non-obese populations, with an HR of 2.38 (95% CI: 1.57-3.59). Conversely, beyond the critical juncture, the upsurge in diabetes risk seems to level off, displaying no significant variation, with an HR of 1.18 (95% CI: 0.98-1.41).ConclusionsThis study reveals a non-linear association between the TG/HDL-c ratios and the likelihood of diabetes in non-obese individuals from East Asia. Maintaining a ratio of TG/HDL-C below 1.36 significantly reduces diabetes risk. However, once the ratio of TG/HDL-C exceeds 1.36, reducing it does not substantially lower diabetes onset risk.

An Improved Machine Learning Framework Considering Spatiotemporal Heterogeneity for Analyzing the Relationship Between Subway Station-Level Passenger Flow Resilience and Land Use-Related Built Environment

The COVID-19 pandemic and similar public health emergencies have significantly impacted global travel patterns. Analyzing the recovery characteristics of subway station-level passenger flow during the pandemic recovery phase can offer unique insights into public transportation operations and guide practical planning efforts. This pioneering study constructs a station-level passenger flow recovery resilience (PFRR) index during the rapid recovery phase using subway AFC system swipe data. Additionally, it develops an analytical framework based on a multiscale geographically weighted regression (MGWR) model, the improved gray wolf optimization with Levy flight (LGWO), and light gradient boosting machine (LightGBM) regression to analyze passenger flow resilience on weekdays and weekends in relation to land use-related built environment types. Finally, SHAP attribution analysis is used to study the nonlinear relationships between built environment variables and PFRR index. The results show significant spatial heterogeneity in the impact of commercial, recreational, and residential land, as well as POI (points of interest) of leisure and shopping on PFRR. On weekdays, the most relevant built environment variables for PFRR are POI of enterprises and shopping numbers. In contrast, the contribution of built environment variables affecting PFRR of weekend is more balanced, reflecting the recovery of non-essential travel on weekends. Most land use-related built environment variables exhibit nonlinear associations with PFRR values. The proposed analytical framework shows significant performance advantages over other baseline models. This study provides unique insights into subway passenger flow characteristics and surrounding land use-related development layouts under the impact of public health emergencies.

Leisure-time physical activity, cardiorespiratory fitness, and cognitive decline in middle-aged and older adults - The ELSA-Brasil study

ObjectivesDementia is a fast-growing public health problem. This study examined the association of physical activity and estimated cardiorespiratory fitness (eCRF) with the risk of cognitive impairment. Study designMulticentric, prospective cohort study. MethodsWe analyzed 10,121 participants of the ELSA-Brasil study. We assessed leisure-time physical activity using the long version of the IPAQ questionnaire and defined moderate-to-vigorous physical activity (MVPA) per week. We applied a non-exercise prediction equation to estimate eCRF and classified participants as unfit (lowest tertile) and fit. Leisure-time MVPA and eCRF were measured at baseline and follow-up. Incident cognitive impairment was based on memory, language, and executive function assessed at baseline and follow-up. ResultsDuring a median of 8.1 (7.8–8.5) years of follow-up, we identified 396 (3.9 %) incident cases of cognitive impairment. There was an inverse, non-linear association between the incidence of cognitive impairment and both leisure time MVPA and eCRF. Low eCRF (IRR: 1.29; 95%CI: 1.02, 1.64) and low MVPA (IRR: 1.40; 1.09, 1.82) were independently associated with an increased incidence. Increasing 1 MET in eCRF from baseline to follow-up visit was associated with a lower incidence of cognitive impairment (IRR: 0.80; 95%CI: 0.71, 0.91), while a decrease of 13.7 min per day in leisure time MVPA is associated with an increased incidence (IRR: 1.16; 95%CI: 1.01, 1.33) of cognitive impairment. These associations remained statistically significant in adults under 65 but not in older adults. ConclusionLow eCRF and leisure time MVPA are strong and independent predictors of incident cognitive impairment especially in middle-aged adults.

Dietary amino acids intake and all-cause and cause-specific mortality: results from the Golestan Cohort Study

BackgroundLess is known whether the amino acid composition of dietary protein sources effects on long-term health outcomes. We aimed to evaluate the association between dietary amino acid composition and all-cause and cause-specific mortality.MethodsThis study used data from the Golestan Cohort Study, which was performed in the Golestan Province of Iran from January 2004 to June 2008. Mortality, which was the primary outcome, was ascertained through September 2022. The Cox proportional hazards regression models were used to determine the adjusted hazard ratios (HR) and 95% confidence intervals (CI) for mortality according to the quintiles of amino acid consumption, taking the third quintile as the reference.ResultsA total of 47,337 participants (27,293 [57.7%] women) with a mean (standard deviation) age of 51.9 (8.9) years were included. During a median follow-up of 15 years, 9,231 deaths were documented. Regarding essential amino acid intakes, the HRs of all-cause mortality were 1.16 (95% CI, 1.07–1.26) in the first quintile, compared with the reference group (P for non-linear trend < 0.001). Similarly, non-linear associations were observed between risk of all-cause mortality and intake of branched-chain, aromatic, sulfur-containing, or non-essential amino acids (P for non-linear trend < 0.001 for all comparisons), with higher HRs for participants in the first quintiles. There was an age interaction for the associations between dietary amino acids and mortality (P for interaction ˂0.05). While high amino acid diets were detrimental in middle-aged adults (< 65 years), increased hazards of mortality were observed among older adults (≥ 65 years) with low amino acid intake.ConclusionsThis study showed the non-linear trend between amino acids intake and risk of mortality in the middle-aged and older Iranian population. Overall, our findings suggest that diets lower in amino acids were associated with increased hazards of mortality, particularly among older adults.

Nonlinear association between platelet to albumin ratio and disease activity in patients with early rheumatoid arthritis

The relationship between the platelet to albumin ratio (PAR) and the disease activity of early rheumatoid arthritis (ERA) remains to be elucidated. This cross-sectional study included 372 patients with ERA who were hospitalized at Xingtai People’s Hospital between January 2022 and January 2024. Multiple linear regression analysis was employed to assess the correlation of PAR with Disease Activity Score 28 (DAS28) using erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), and then generalized additive models were used to explore their relationship. After accounting for confounding variables, a positive correlation was observed between the PAR and DAS28-ESR and DAS28-CRP in ERA patients (β (95% CI): 0.20 (0.08, 0.32) and 0.20 (0.08, 0.33), respectively), and the general trends were consistent from the lowest tertile group (T1) to the highest tertile group (T3). Furthermore, a nonlinear relationship was identified between PAR and both DAS28-ESR and DAS28-CRP. Threshold effect analysis indicated that a value of 13.73 was a significant inflection point. In brief, PAR has a threshold effect on the disease activity of ERA. Increased PAR levels were independently positive associated with DAS28-ESR and DAS28-CRP among ERA patients with PAR < 13.73.

Non-linear relationship between lipid accumulation products and risk of diabetes in Japanese adults

The lipid accumulation product (LAP) is a novel, sex-specific indicator of lipid accumulation. While previous studies have investigated the relationship between LAP and diabetes, they have not specifically addressed potential sex differences in this association. The present study explores the potential sex-specific differences in the relationship between LAP and diabetes mellitus (DM) risk in the Japanese population. From 2004 to 2015, a total of 15,263 Japanese individuals without DM underwent physical assessments at Murakami Memorial Hospital. The association between LAP and incident diabetes was analyzed using Cox proportional hazards regression models, incorporating cubic spline functions and smooth curve fitting to identify potential non-linear relationships. Subgroup and sensitivity analysis assessments were conducted to validate the robustness of our findings. After adjusting for covariates, a positive association between LAP and DM risk was observed in both females (HR: 1.02, 95% CI: 1.00-1.03, P = 0.0138) and males (HR: 1.01, 95% CI: 1.00-1.01, P = 0.0314). A non-linear association between LAP and incident DM was identified for both sexes. The inflection points for LAP were 16.58 for females and 11.11 for males. In females, the HR to the left and right of the inflection point were 1.09 (95% CI: 1.02–1.17) and 1.01 (95% CI: 1.00-1.03), respectively. In males, the HR to the left and right of the inflection point were 0.92 (95% CI: 0.86–0.98) and 1.01 (95% CI: 1.00-1.01), respectively. Sensitivity analysis indicated a stronger association between LAP and DM risk. Elevated baseline LAP levels were associated with an increased risk of incident DM, with the relationship exhibiting non-linear characteristics. These findings suggest that maintaining lower LAP levels may help mitigate the risk of developing diabetes.

The association between android-to-gynoid lean mass ratio and all-cause and specific-cause mortality in US adults: A prospective study.

The associations of lean mass distribution with mortality risk are not fully elucidated. We aimed to evaluate the effects of a new lean mass distribution indicator-android/gynoid lean mass ratio (AGLR) evaluated by dual-energy x-ray absorptiometry (DXA) on the risk of all-cause and specific-cause mortality in a NHANES cohort. This was a population-based cohort study, which included 18 542 subjects aged 20 years and older from the US National Health and Nutrition Examination Survey (US NHANES, 2003-2006 and 2011-2018). The primary outcomes of our study were all-cause mortality, cardiovascular (CVD) mortality and cancer mortality, which were obtained from the linkage to registries. Cox proportional hazard regression models were used to investigate the association between lean mass distribution and mortality risk among the US NHANES general population. Restricted cubic spline nested in Cox regression was also used to test whether there was a non-linear association of AGLR as a continuous variable with the risk of mortality. During a median follow-up of 6.9 years, 1412 participants died, of whom 435 were due to CVD and 340 were due to cancer. The multivariable-adjusted (Model 4) hazard ratios (HRs) for each SD increase in AGLR were 1.53 (95% confidence interval [CI] 1.40-1.67) for all-cause mortality, 1.56 (95% CI 1.30-1.87) for cancer mortality and 1.64 (95% CI 1.47-1.84) for CVD mortality. The associations were robust in sensitivity analyses and present in most subgroups. AGLR evaluated by DXA was associated with a higher risk of all-cause and specific-cause mortality among the general population from the US NHANES cohort.

Adolescents’ dietary patterns, their drivers and association with double burden of malnutrition in adolescents: a cross-sectional study in Kenya’s urban slums

BackgroundThe double burden of malnutrition (DBM) during adolescence is associated with growth and developmental impairment and risk of non-communicable diseases. There is limited evidence on adolescent’s dietary patterns (DPs), and how they contribute to DBM in urban low income contexts in sub Saharan Africa. This study assessed DPs of adolescents, their drivers and association with DBM in Kenya’s urban slums.MethodsAnthropometric, socio-demographic and dietary-intake data were collected through a cross-sectional survey of 621 adolescents from three major urban slums in Nairobi, Kenya. DPs were derived using principal component analysis. Multinomial-logistic-regression was used to assess the association between the DPs, individual and environmental factors and DBM.ResultsTwo DPs were identified: traditional DP (whole grains/cereals, rice, fruits, legumes/nuts, and water) and transitioning DP (refined cereals (maize/wheat), vegetables, meat, tea/coffee, sweet ultra-processed/deep fried snacks). Adolescents from Mathare (the largest slum) were more likely to adhere to the traditional DP (RRR = 3.43; 95% CI 1.85–6.37). Cultural background (Luo) had a positive association (RRR = 4.28; 95% CI 1.97–9.32), while longer residency in the slum (> 10 years) had a negative association (RRR = 0.47; 95% CI 0.25–0.90) with transitioning DP. The transitioning DP had a positive (non-linear) association with overweight/obesity in girls (RRR = 2.79; 95% CI 1.16–6.71). The DPs were not associated with thinness or stunting.ConclusionThe DPs indicate various stages of nutrition transition of adolescent diets, which are influenced by cultural background, neighbourhood and duration of stay in the slum. Transitioning DP may expose adolescents to the risks of overweight/obesity in the long-term.

A cross-sectional study of the impact of stigma on quality of life in hemiplegic stroke patients following suicide attempts in nursing homes

To analyze the factors affecting stigma and quality of life in hemiplegic stroke patients following suicide attempts in nursing homes and to provide a theoretical basis for developing interventions in clinical care. General demographic information, the Stigma Scale for Chronic Illness (SSCI), and the Quality of Life Scale (SF-36) were used to investigate 259 patients with hemiplegia after stroke following nursing home suicide from January to April 2024. Univariate statistical analyses were performed to assess the impact of potential determinants on quality of life. Multiple regression models and stratified analyses with smoothed curve fitting were used for further evaluation. Multiple regression modeling showed that the factors influencing the quality of life in hemiplegic stroke patients following suicide attempts in nursing homes were stigma, Age, marital status, education, type of occupation, monthly household income, and duration of illness. The level of quality of life before unadjusted variables was strongly associated with high school and college education (β = 11.9, 95% CI: 8.2–15.6; P < 0.001), (β = 13.1, 95% CI: 9.2 -16.9; P < 0.001). After adjusting for confounders such as marital status (Married, Unmarried), Age (< 30, 30–40, 40–50, > 50) (β = 8.1, 95% CI: 4 .6–11.6; P < 0.0001). (β = 9.5, 95% CI: 6.0–13.1;P < 0.0001), the results were not significantly different. Curve fitting revealed threshold nonlinear associations between intrinsic and extrinsic stigma and quality of life, with quality of life decreasing as stigma increased. Conclusion Stigma is negatively correlated with the level of quality of life in hemiplegic stroke patients following suicide attempts in nursing homes. Different demographic profiles moderated patients’ quality of life levels, and effective psychological intervention strategies should be used to improve patients’ quality of life.