The association between weight-adjusted-waist index and abdominal aortic calcification in adults aged ≥ 40 years: results from NHANES 2013-2014

Association of Life's Essential 8 with abdominal aortic calcification and mortality among middle-aged and older individuals

AIM

To assess the association of Life's Essential 8 (LE8) and the presence of abdominal aortic calcification (AAC) with mortality among middle-aged and older individuals.

METHODS

Participants aged older than 40 years were enrolled from the National Health and Nutrition Examination Survey 2013-2014. AAC was assessed using dual-energy X-ray absorptiometry. Mortality data were ascertained through linkage with the National Death Index until 31 December 2019. The LE8 score incorporates eight components: diet, physical activity, nicotine exposure, sleep health, body mass index, blood lipids, blood glucose and blood pressure. The total LE8 score, an unweighted average of all components, was categorized into low (0-49), medium (50-79) and high (80-100) scores.

RESULTS

This study included 2567 individuals, with a mean LE8 score of 67.28 ± 0.48 and an AAC prevalence of 28.28%. Participants with low LE8 scores showed a significantly higher prevalence of AAC (odds ratio = 2.12 [1.12-4.19]) compared with those with high LE8 scores. Over a median 6-year follow-up, there were 222 all-cause deaths, and 55 cardiovascular deaths occurred. Participants with AAC had an increased risk of all-cause (hazard ratio [HR] = 2.17 [1.60-2.95]) and cardiovascular (HR = 2.35 [1.40-3.93]) mortality. Moreover, individuals with AAC and low or medium LE8 scores exhibited a 137% (HR = 2.37 [1.58-3.54]) and 119% (HR = 2.19 [1.61-2.99]) higher risk of all-cause mortality, as well as a 224% (HR = 3.24 [1.73-6.04]) and 125% (HR = 2.25 [1.24-4.09]) increased risk of cardiovascular mortality, respectively.

CONCLUSIONS

The LE8 score correlates with AAC prevalence in middle-aged and older individuals and serves as a valuable tool for evaluating the risk of all-cause and cardiovascular mortality in individuals with AAC.

The negative association between weight-adjusted-waist index and lung functions: NHANES 2007-2012

Obesity is a common public health issue worldwide, and its negative impact on lung function has garnered widespread attention. This study sought to investigate the possible association between a new obesity metric, the weight-adjusted waist index (WWI), and lung functions, providing a basis for the monitoring and protection of lung functions. We conducted a cross-sectional evaluation, analyzing data from adults in the U.S. gathered through the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2012. To explore the correlation between WWIs and lung functions, we utilized a multivariate logistic regression model with appropriate weighting to ensure accuracy. Smooth curve fitting also helped to confirm the linear nature of this relationship. Subgroup analyses were conducted to confirm the uniformity and dependability of the results. Our study included data from 13,805 adults in the United States. Multivariate linear regression analysis revealed that, in the fully adjusted model, higher WWIs were negatively correlated with forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), FEV1/FVC, peak expiratory flow rate (PEF), and forced expiratory flow rate (FEF) 25%-75% (β = -0.63; 95% confidence interval [CI] [-0.71, -0.55]; β = -0.55; 95% CI [-0.62, -0.48]; β = -0.02; 95% CI [-0.03, -0.01]; β = -1.44; 95% CI [-1.65, -1.23]; β = -0.52; 95% CI [-0.65, -0.39], respectively). Additionally, when analyzing the WWI as a categorical variable, a significant downward trend in the FVC, FEV1, PEF, and FEF 25%-75% was observed from Q2 to Q4 as the WWI increased (trend P < 0.05). Subgroup analysis showed stronger associations between WWI and lung functions, particularly among younger, non-Hispanic white, male participants, and current smokers. Our results indicate that elevated WWI is strongly associated with declining lung functions, demonstrating the importance of long-term monitoring and tracking of WWIs.

Association of weight-adjusted-waist index with all-cause and cardiovascular mortality in individuals with diabetes or prediabetes: a cohort study from NHANES 2005-2018

Weight-adjusted waist index (WWI) is a new marker of central obesity. This study explored the association of WWI with all-cause and cardiovascular disease (CVD) mortality in individuals with diabetes or prediabetes. 6551 participants with diabetes or prediabetes from the National Health and Nutrition Examination Survey (NHANES) records between 2005 and 2018 were included. The association of WWI with all-cause and CVD mortality was assessed using Kaplan-Meier survival analysis, Cox proportional hazards model (Cox regression), and restricted cubic spline (RCS). The predictive value of WWI for mortality was analyzed using time-dependent receiver operating characteristic curves (ROC). There were 1083 all-cause deaths and 360 CVD deaths. Multivariable-adjusted Cox regression analyses showed WWI was positively correlated with the risk of all-cause and CVD mortality in subjects with diabetes or prediabetes. Multivariate-adjusted RCS analyses showed a linear and positive correlation of WWI with all-cause mortality risk, and a nonlinear relationship with CVD mortality, with a threshold of 12.35. The area under the curve (AUC) for 3, 5, and 10-years survival for all-cause mortality was 0.795, 0.792, and 0.812, respectively, and for CVD mortality was 0.815, 0.833, and 0.831, respectively. WWI is a valuable predictor of all-cause mortality risk in patients with diabetes and prediabetes, and a valuable predictor of CVD mortality risk when patients with diabetes and prediabetes are considered as a whole.

The relationship between weight-adjusted-waist index, body mass index and diabetic retinopathy among American adults: a population-based analysis

Diabetic retinopathy (DR) is a common complication of diabetes, with its prevalence increasing globally. While previous research has linked obesity indices such as body mass index (BMI) to DR, the association with weight-adjusted-waist index (WWI) remains unclear. Additionally, the relationship between WWI and DR has not been fully elucidated. This cross-sectional study analyzed data from the National Health and Nutrition Examination Survey (2005-2008) to investigate these associations in Americans aged 40 and above. The study included 5436 participants (2705 men and 2731 women). Weighted logistic regression analysis revealed a significant increase in DR prevalence with higher WWI and BMI values. Smooth curve analysis demonstrated a linear correlation between WWI and DR. The findings suggest that both WWI and BMI are independently associated with DR risk among older US adults, highlighting the importance of considering central obesity measures in assessing diabetic complications.

The association between weight-adjusted waist index and sleep disorders in U.S. adults: results from NHANES 2005-2008

The detrimental effects of obesity on sleep disorders have garnered a lot of interest. The weight-adjusted waist index (WWI) is a newly developed anthropometric index calculated in terms of weight and waist circumference. The body mass index has been employed to evaluate obesity in the majority of studies that connect obesity to sleep disorders. This study seeks to investigate the correlation between WWI and sleep disorders among adults in the United States. This cross-sectional study was part of the National Health and Nutrition Examination Survey and included adults aged >20 from 2005 to 2008. This study investigated the linear relationship between sleep disorders and WWI using weighted binary logistic regression models. Nonlinear relationships were characterized using smooth curve fitting and threshold effects analyses. After that, based on variables like gender, age, marital status, diabetes, hypertension, and smoking, subgroup analyses were performed. Our study included 9869 participants who were at least 20 years old. Higher WWI was linked to greater odds of sleep disorders prevalence, according to weighted binary logistic regression (odds ratio = 1.15; 95% confidence interval, 1.10, 1.20). In subgroup analyses based on age, marital status, diabetes, hypertension, and smoking, this connection remained robust. However, there were notable differences in this connection depending on gender. Furthermore, a nonlinear correlation with inflection points between WWI and sleep disorders was shown using smooth curve fitting. The nonlinear association between WWI and sleep disorders has an inflection point of 8.1 cm/√kg, as indicated by the threshold effect analyses. A higher WWI exposure may elevate the odds of sleep disorder prevalence, underscoring the importance of considering WWI in the prevention and management of sleep disorders.

Relationship between weight-adjusted-waist index and blood pressure as well as incident hypertension among middle-aged and elderly Chinese: A longitudinal study

BACKGROUND AND AIM

The Weight-Adjusted Waist Index (WWI) is a novel obesity metric linked to metabolic disorders. Its relationship with blood pressure and hypertension prevalence in middle-aged and elderly Chinese is unclear. This study examined the association between WWI, blood pressure, and hypertension incidence.

METHODS AND RESULTS

This cross-sectional study included 9298 participants from the China Health and Retirement Longitudinal Study, with 4120 non-hypertensive individuals enrolled in the cohort study. In the cross-sectional analysis, WWI was positively associated with systolic blood pressure (SBP) (Beta 0.88, 95% CI: 0.57-1.21, p < 0.001), showing stronger correlations than waist circumference (WC) (Beta 0.20, 95% CI: 0.16-0.23, p < 0.001) and body mass index (BMI) (Beta 0.63, 95% CI: 0.52-0.74, p < 0.001). WWI also showed a positive association with diastolic blood pressure (DBP) (Beta 0.51, 95% CI: 0.32-0.69, p < 0.001), stronger than those with WC (Beta 0.13, 95% CI: 0.11-0.15, p < 0.001) and BMI (Beta 0.43, 95% CI: 0.37-0.50, p < 0.001). In the longitudinal cohort study, there were 1325 (32%) incident cases of hypertension by the end of follow-up. WWI was positively associated with incident hypertension (OR 1.11, 95% CI: 1.04-1.18, p = 0.001), with a stronger predictive value than WC (OR 1.02, 95% CI: 1.01-1.03, p < 0.001) and BMI (OR 1.04, 95% CI: 1.02-1.06, p < 0.001).

CONCLUSION

Elevated WWI may serve as an independent risk factor for incident hypertension in the middle-aged and elderly Chinese population.

The association between weight-adjusted-waist index and psoriasis: A cross-sectional study

INTRODUCTION

This study explored the association between psoriasis and the weight-adjusted waist index (WWI), a newly developed measure of adiposity. The research was conducted among adults in the United States.

METHODS

Utilizing survey data from the National Health and Nutrition Examination Survey (NHANES) spanning the years 2009 to 2014, the present study aimed to investigate the potential correlation between psoriasis and WWI within a sample of 15,920 adult participants. Employing multivariable logistic regression and nonlinear curve fitting techniques, we analyzed this plausible association. Additionally, a subgroup analysis was conducted to ascertain the consistency across diverse populations.

RESULTS

A significant positive association was discovered between psoriasis and WWI in the investigated sample of 15,920 adults. After conducting a comprehensive adjustment of the model, it was observed that each incremental unit of WWI was significantly associated with an 14% elevated likelihood of developing psoriasis (OR = 1.16, 95% CI 1.01-1.36). Moreover, individuals belonging to the highest quartile of WWI exhibited a 47% higher risk of psoriasis compared to those in the lowest quartile (OR = 1.44, 95% CI 1.01-2.06). This positive correlation remained consistent across various subgroups. The study also compared WWI with BMI and waist circumference, finding that WWI is a more stable metric of obesity.

CONCLUSIONS

Our study suggested that in US adults, there is a positive association between WWI and psoriasis. It also indicated that WWI showed potential as a valuable index of psoriasis among the general population.

Association between weight-adjusted waist index and bone mineral density in adolescents

The negative effects of obesity and excess body fat on bone mineral density (BMD) have been widely reported. As opposed to waist circumference (WC) or body mass index (BMI), weight-adjusted waist index (WWI) is a superior method for assessing obesity. WWI also indicates centripetal obesity independently of the weight of the individual. An investigation of WWI and adolescents' BMD was conducted in this study. The National Health and Nutrition Examination Survey (NHANES) 2011-2018 provided the data for this cross-sectional investigation. In this study, weighted multivariate logit models were employed to assess the correlation between teenage BMD and WWI. Additionally, we conducted interaction tests and subgroup analysis. Through multivariate linear regression, we discovered that WWI was negatively linked with lumbar, trunk, and total BMD but not pelvis BMD in this study, which included 6828 subjects. We found that each unit increase in WWI resulted in a lumbar BMD decline of 0.04 g/cm2 (95%CI -0.04, -0.04), a trunk BMD decrease of 0.03 g/cm2 (95%CI -0.03, -0.02), and a total BMD decrease of 0.02 g/cm2 (95%CI -0.02, -0.02). In conclusion, in US teenagers, there were negative connections discovered between WWI and lumbar, trunk, and total BMD, but not pelvis BMD.

Association between the serum uric acid/serum creatinine ratio and cognitive function in older adults: NHANES in the United States

Cognitive impairment can potentially become a significant health concern in older adults. However, early effective diagnostic methods are still lacking. Therefore, we utilized the NHANES database in the US to investigate the relationship between serum uric acid to serum creatinine (SUA/SCR) ratio and cognitive impairment. In our study, a total of 3874 participants were included (2001-2002, 2011-2014). Weighted t tests or chi-square tests were utilized to analyze the basic characteristics of the population. Weighted logistic regression analysis, smooth-fit curves, threshold effects, and subgroup analysis were conducted to investigate the correlation between the SUA/SCR and cognitive impairment. In this study, the SUA/SCR was significantly lower in individuals with cognitive impairment. The logistic regression model, after adjusting for all covariates, revealed that the Q2-Q4 were 0.65 (95% CI 0.49, 0.86), 0.60 (95% CI 0.40, 0.90), 0.55 (95% CI 0.39, 0.77) respectively. This indicates that participants in the Q4 had a 45% reduced risk of cognitive impairment. Smooth-fit curves and threshold effect analysis revealed a nonlinear relationship between SUA/SCR and cognitive impairment, with a turning point at 4.13. Subgroup analysis showed no statistically significant differences in the relationship between SUA/SCR and cognitive impairment among different subgroups (P > 0.05). Our findings indicate a negative correlation between the SUA/SCR and the risk of cognitive impairment in the population of adults aged 60 and above in the US. This suggests that the SUA/SCR holds promise as a potential indicator for cognitive impairment.

Associations between waist-to-height ratio and abdominal aortic calcification: A cross-sectional study

Waist-to-height ratio (WtHR) is a validated biomarker of central obesity that appears to be preferable to other body composition measurements in the evaluation of cardiovascular disease. The goal of this research was to explore the connection between WtHR and abdominal aortic calcification (AAC) among adults. On the basis of data from the 2013 to 2014 National Health and Nutrition Examination Survey, multivariate logistic regression, sensitivity analysis, as well as smoothed curve fitting were used to evaluate the connection between WtHR and AAC. Subgroup analyses along with interaction tests were done to see if this link was consistent across populations. Among 3079 participants aged >40 years, there was a negative association between WtHR and ACC. Each 1-unit emergence of WtHR was related to a 2% reduction in the probability of severe AAC in the entirely adjusted model (odds ratio = 0.02, 95% confidence interval: [0.00-0.12]). Participants in the highest WtHR quartile were 39% less likely to acquire severe AAC compared with those in the lowest quartile. (odds ratio = 0.61, 95% confidence interval: [0.37-1.00]). This negative association was more pronounced in the diabetes subgroup. We discovered a reversed U-shaped association between WtHR as well as AAC score utilizing a 2-stage linear regression model, with an intersection point of 0.56. WtHR was negatively associated with AAC among US adults.

Association of weight-adjusted waist index with all-cause mortality among non-Asian individuals: a national population-based cohort study

INTRODUCTION

The Weight-Adjusted Waist Index (WWI) is a new indicator of obesity that is associated with all-cause mortality in Asian populations. Our study aimed to investigate the linear and non-linear associations between WWI and all-cause mortality in non-Asian populations in the United States, and whether WWI was superior to traditional obesity indicators as a predictor of all-cause mortality.

METHODS

We conducted a cohort study using data from the 2011-2018 National Health and Nutrition Examination Survey (NHANES), involving 18,592 participants. We utilized Cox proportional hazard models to assess the association between WWI, BMI, WC, and the risk of all-cause mortality, and performed subgroup analyses and interaction tests. We also employed a receiver operating characteristics (ROC) curve study to evaluate the effectiveness of WWI, BMI, and WC in predicting all-cause mortality.

RESULTS

After adjusting for confounders, WWI, BMI, and WC were positively associated with all-cause mortality. The performance of WWI, BMI, and WC in predicting all-cause mortality yielded AUCs of 0.697, 0.524, and 0.562, respectively. The data also revealed a U-shaped relationship between WWI and all-cause mortality. Race and cancer modified the relationship between WWI and all-cause mortality, with the relationship being negatively correlated in African Americans and cancer patients.

CONCLUSIONS

In non-Asian populations in the United States, there is a U-shaped relationship between WWI and all-cause mortality, and WWI outperforms BMI and WC as a predictor of all-cause mortality. These findings may contribute to a better understanding and prediction of the relationship between obesity and mortality, and provide support for effective obesity management strategies.

The association between weight-adjusted-waist index and stress urinary incontinence in female adults: a population-based study

INTRODUCTION

Obesity has a significant impact on female stress urinary incontinence. The weight-adjusted-waist index (WWI), a newly explored metric for measuring physical obesity and stress urine incontinence, has not been investigated.

METHODS

Cross-sectional data were obtained from the 2011 to 2018 National Health and Nutrition Examination Survey (NHANES) of participants with complete data for WWI and SUI. The independent connection between WWI and SUI was examined using weighted multivariable logistic regression analyses. Smoothed curve fitting was used to study their relationship. In addition, subgroup analyses were performed, and interaction tests were undertaken.

RESULTS

In 2,361 female participants over 20, WWI and SUI showed a positive association. Model 3 found that for each one-unit increase in WWI, SUI prevalence increased by 38% [1.38 (1.20, 1.59)]. The prevalence of SUI was 84% higher among participants in the highest quartile of WWI compared to those in the lowest quartile [1.84 (1.32, 2.57)]. Observed nonlinear positive correlation between WWI and SUI was revealed through smoothed curve fitting. In addition, we found that WWI was more strongly associated with SUI than traditional indicators of obesity, including BMI and weight.

CONCLUSIONS

Females with higher weight-adjusted waist index levels were more likely to develop stress urinary incontinence and have a stronger correlation than traditional indicators of obesity. According to our research, WWI may help detect women's stress urinary incontinence (SUI), and managing obesity through the WWI index may reduce SUI prevalence rates.

Systemic immune-inflammatory index and its association with female sexual dysfunction, specifically low sexual frequency, in depressive patients: Results from NHANES 2005 to 2016

Sexual dysfunction, particularly in females, is a complex issue influenced by various factors, including depression and inflammation. The Systemic immune-inflammation index (SII), an inflammatory biomarker, has shown associations with different health conditions, but its relationship with female sexual dysfunction (FSD) remains unclear. This study aimed to investigate the association between SII and FSD in the context of depression, utilizing low sexual frequency as an assessment indicator. Data from the National Health and Nutrition Examination Survey (NHANES) 2005 to 2016, involving 1042 depressed female participants, were analyzed. FSD, indicated by low sexual frequency, and SII, derived from complete blood count results, were assessed. Logistic regression and subgroup analyses were conducted, considering demographic and health-related factors. A total of 1042 individuals were included in our analysis; 11.5163% of participants were categorized as having FSD, which decreased with the higher SII tertiles (tertile 1, 13.8329%; tertile 2, 13.5447%; tertile 3, 7.1839%; p for trend < 0.0001). Multivariate linear regression analysis showed a significant negative association between SII and FSD [0.9993 (0.9987, 0.9999)]. This negative association in a subgroup analysis is distinctly and significantly present in the Mexican American subgroup [0.9959 (0.9923, 0.9996)], while it does not reach statistical significance in other racial categories. Furthermore, the association between SII and FSD was nonlinear; using a 2-segment linear regression model, we found a U-shaped relationship between SII and FSD with an inflection point of 2100 (1000 cells/µL). In summary, in depressed individuals, a higher SII is independently associated with a decreased likelihood of FSD, emphasizing the potential role of inflammation in female sexual health.

The relationship between weight-adjusted-waist index and suicidal ideation: evidence from NHANES

BACKGROUND

Amidst growing evidence of the intricate link between physical and mental health, this study aims to dissect the relationship between the waist-to-weight index (WWI) and suicidal ideation within a representative sample of the US population, proposing WWI as a novel metric for suicide risk assessment.

METHODS

The study engaged a sample of 9500 participants in a cross-sectional design. It employed multivariate logistic and linear regression analyses to probe the association between WWI and suicidal ideation. It further examined potential nonlinear dynamics using a weighted generalized additive model alongside stratified analyses to test the relationship's consistency across diverse demographic and health variables.

RESULTS

Our analysis revealed a significant positive correlation between increased WWI and heightened suicidal ideation, characterized by a nonlinear relationship that persisted in the adjusted model. Subgroup analysis sustained the association's uniformity across varied population segments.

CONCLUSIONS

The study elucidates WWI's effectiveness as a predictive tool for suicidal ideation, underscoring its relevance in mental health evaluations. By highlighting the predictive value of WWI, our findings advocate for the integration of body composition considerations into mental health risk assessments, thereby broadening the scope of suicide prevention strategies.

Association between Weight-Adjusted Waist Index and depressive symptoms: A nationally representative cross-sectional study from NHANES 2005 to 2018

BACKGROUND

Depressive symptoms are strongly associated with the development of various diseases and are one of the leading causes of disability in the world. However, the relationship between weight-adjusted waist index (WWI) and depressive symptoms has not been studied. This study aimed to assess the relationship between depressive symptoms and WWI.

METHODS

This study took NHANES data from 2005 to 2018 with 32,374 participants. Depressive symptoms were measured by a questionnaire (PHQ-9).WWI was determined by dividing the square root of waist circumference (cm) by weight (kg). Multivariate logistic regression models, smoothed curve fitting, and weighted generalized additive model (GAM) regression were used to examine the relationship between depressive symptoms and WWI, BMI, and waist circumference. Subgroup analyses and interaction tests were also performed.

RESULTS

In fully adjusted models, the OR (95 % CI) for WWI and depressive symptoms with WWI, BMI, and waist circumference were 1.18 (1.05, 1.34), BMI 1.01 (1.00, 1.02, 1.01 (1.00, 1.01), respectively. Participants in the highest quartile (Q4) had a 49 % higher depressive symptoms compared to those in the lowest quartile (Q1) (OR = 1.49, 95 % CI:1.14-1.96). Subgroup analyses and interaction tests showed a stable relationship between depressive symptoms and WWI.

LIMITATIONS

It is difficult to determine a causal relationship between the two; questionnaire collection may be somewhat biased; CONCLUSIONS: WWI was positively associated with depressive symptoms. This association was stronger than BMI and waist circumference. However, this relationship was stable. This study emphasizes the potential utility of WWI in preventing depressive symptoms and improving prognosis in the population.

Associations between pan-immune-inflammation value and abdominal aortic calcification: a cross-sectional study

Background

Abdominal aortic calcification (AAC) pathogenesis is intricately linked with inflammation. The pan-immune-inflammation value (PIV) emerges as a potential biomarker, offering reflection into systemic inflammatory states and assisting in the prognosis of diverse diseases. This research aimed to explore the association between PIV and AAC.

Methods

Employing data from the National Health and Nutrition Examination Survey (NHANES), this cross-sectional analysis harnessed weighted multivariable regression models to ascertain the relationship between PIV and AAC. Trend tests probed the evolving relationship among PIV quartiles and AAC. The study also incorporated subgroup analysis and interaction tests to determine associations within specific subpopulations. Additionally, the least absolute shrinkage and selection operator (LASSO) regression and multivariable logistic regression were used for characteristics selection to construct prediction model. Nomograms were used for visualization. The receiver operator characteristic (ROC) curve, calibration plot and decision curve analysis were applied for evaluate the predictive performance.

Results

From the cohort of 3,047 participants, a distinct positive correlation was observed between PIV and AAC. Subsequent to full adjustments, a 100-unit increment in PIV linked to an elevation of 0.055 points in the AAC score (β=0.055, 95% CI: 0.014-0.095). Categorizing PIV into quartiles revealed an ascending trend: as PIV quartiles increased, AAC scores surged (β values in Quartile 2, Quartile 3, and Quartile 4: 0.122, 0.437, and 0.658 respectively; P for trend <0.001). Concurrently, a marked rise in SAAC prevalence was noted (OR values for Quartile 2, Quartile 3, and Quartile 4: 1.635, 1.842, and 2.572 respectively; P for trend <0.01). Individuals aged 60 or above and those with a history of diabetes exhibited a heightened association. After characteristic selection, models for predicting AAC and SAAC were constructed respectively. The AUC of AAC model was 0.74 (95%CI=0.71-0.77) and the AUC of SAAC model was 0.84 (95%CI=0.80-0.87). According to the results of calibration plots and DCA, two models showed high accuracy and clinical benefit.

Conclusion

The research findings illuminate the potential correlation between elevated PIV and AAC presence. Our models indicate the potential utility of PIV combined with other simple predictors in the assessment and management of individuals with AAC.

Association between weight-adjusted waist index and myopia in adolescents and young adults: results from NHANES 1999-2008

BACKGROUND

Previous studies have indicated a possible link between obesity and myopia, although the results have varied. The objective of this study was to investigate the correlation between a new measure of obesity, the weight-adjusted waist index (WWI), and myopia.

METHOD

This cross-sectional study included individuals between the ages of 12 and 25 who participated in a noncycloplegic vision examination as part of the National Health and Nutrition Examination Survey (NHANES) conducted from 1999 to 2008. WWI was calculated as waist circumference divided by the square root of body weight. Myopia was characterized by a spherical equivalent (SE) of ≤ - 0.5 diopters (D) and further categorized into mild (-3.00D < SE≤-0.50 D), moderate (-6.00D < SE ≤-3.00 D), or high (SE≤-6.00 D). We utilized a weighted multivariable logistic regression and a generalized additive model to evaluate the correlation between WWI and myopia. Threshold effects were analyzed, and we performed subgroup analysis and interaction tests.

RESULTS

A grand total of 11,180 individuals were registered for the study. Decreased myopia severity was observed with higher WWI, as evidenced by elevated SE (β = 0.098, 95% CI: 0.028-0.167). Individuals in the top tertile of WWI experienced a 19.8% decrease in risk compared to those in the lowest group (OR = 0.802, 95% CI: 0.800-0.804; P for trend < 0.001). Similar associations were observed for high myopia. Gender-specific nonlinear associations were found, with different breakpoints for males (10.774) and females (10.025). In males, a significant positive association was found on the right side of the breakpoint (OR = 1.398, 95% CI: 1.038-1.884), while no significant association was found on the left side. Conversely, among females, a negative association was observed on the left side of the breakpoint (OR = 0.679, 95% CI: 0.512-0.899), whereas no notable correlation was detected on the right side.

CONCLUSION

Increased WWI level was linked to a lower risk of myopia and high myopia in the overall sample, with gender-specific variations.

Accelerated Bone Loss in Older Men With Severe Abdominal Aortic Calcification-the Prospective MINOS Study

CONTEXT

Data on the association between the severity of abdominal aortic calcification (AAC) and bone loss are discordant.

OBJECTIVE

Our aim was to assess the association between baseline AAC and prospectively assessed bone loss in older men.

METHODS

This prospective cohort study started in 1995 (MINOS). Men aged 50 to 85 years (n = 778) had AAC assessed on the lateral radiograph of the spine using Kauppila's semiquantitative score and was followed prospectively for 7.5 years. Bone mineral density (BMD) and bone mineral content (BMC) were measured by dual-energy x-ray absorptiometry every 18 months. Statistical analysis was performed using linear mixed models.

RESULTS

In comparison to men without AAC (AAC = 0), severe AAC (>6) was associated with more rapid bone loss at the total hip (-0.62 ± 0.06 vs -0.32 ± 0.04%/year; P < .001), trochanter, and distal forearm (-0.72 ± 0.06 vs -0.45 ± 0.03%/year; P < .001). The highest decile (AAC >10) was associated with more rapid bone loss at the femoral neck, whole body, and ultradistal radius (-0.86 ± 0.12 vs -0.34 ± 0.05%/year; P < .001). The results were similar for BMD and for BMC. The patterns were similar in sensitivity analyses (eg, after excluding men with abdominal obesity, after excluding current smokers, after excluding men with ischemic heart disease or with diabetes mellitus, after excluding men with abnormal concentrations of lipids, bioavailable 17β-estradiol or 25-hydroxycholecalciferol, after excluding men with glomerular filtration rate <60 mL/min).

CONCLUSION

Severe AAC is associated with faster bone loss in older men and may contribute to the higher fracture risk observed in this population.

The association between weight-adjusted-waist index and self-reported infertility among women of reproductive age in the United States

AIM

This study aimed to determine whether the weight-adjusted-waist index (WWI) affected infertility in women of childbearing age in the United States.

METHODS

In this study, a database from the 2013 to 2018 National Health and Nutrition Examination Survey (NHANES) was used. We analyzed 3374 participants' data cross-sectionally. The survey used WWI and fertility status as independent and dependent variables. To determine the effect of WWI, an analysis of the independent relationship between WWI and infertility was conducted using weighted multivariable logistic regression and a generalized additive mode (GAM). A smooth curve fitting test was used to calculate whether there was a linear association between WWI and the incidence rate of infertility, as well as subgroup analyses and interaction tests.

RESULTS

The prevalence of infertility was 10.19% among 3374 participants. Higher WWI quartiles were associated with higher infertility rates. Based on a fully adjusted model, the effects of WWI on fertility were positive (odds ratio = 1.39, 95% confidence interval: 1.17-1.66). As a result of smooth curve fitting, the association was linear across the entire WWI. Different characteristics were associated with different risks of infertility in subgroup analysis.

CONCLUSION

Among women of reproductive age in the United States, WWI levels were positively associated with infertility. This relationship needs to be confirmed by further studies.

Relationship between weight-adjusted waist circumference index and prevalence of gallstones in U.S. adults: a study based on the NHANES 2017-2020

Objective

We aimed to assess the association between weight-adjusted waist circumference index (WWI) and gallstone prevalence in US adults.

Methods

We selected individuals from the National Health and Nutrition Examination Survey (NHANES) database from 2017 to 2020 and used logistic regression analyses, subgroup analyses, and dose-response curves to assess the association between WWI and gallbladder stone prevalence and age, sex, and ethnicity.

Results

A total of 7971 participants aged ≥20 years were enrolled in our study; 828 patients had a self-reported history of gallstones. After correcting for confounders, for each unit of WWI after Ln conversion, the prevalence of gallbladder stones increased by 34% (OR=1.34, 95% CI:1.20, 1.50). Dose-response curves showed a positive correlation between WWI and gallbladder stone prevalence.According to the subgroup analysis, the positive association between TyG index and high-frequency HI was more significant in males(OR=1.34, 95% CI:1.07, 1.69), <40 years old(OR=1.42, 95% CI:1.18, 1.71), white people Americans(OR=1.35, 95% CI:1.08, 1.68) and other races(OR= 1.56, 95% CI:1.13, 2.14).

Conclusion

Higher WWI was positively associated with the prevalence of gallbladder stones and was associated with gender, age, and ethnicity. This is noteworthy, although a causal relationship could not be established.

Higher weight-adjusted waist index is associated with increased likelihood of kidney stones

Objectives

The objective of this study was to evaluate the association between weight-adjusted waist index (WWI) and the prevalence of kidney stones among adults in the United States.

Methods

The cross-sectional study utilized data from the National Health and Nutrition Examination Survey (NHANES) spanning the years 2007-2018. A total of 31,344 participants were categorized into two groups: those with kidney stones and those without. WWI was determined by dividing waist circumference (cm) by the square root of body weight (kg). To examine the relationship between kidney stones and WWI, multivariate logistic regression models, smoothed curve fitting, and weighted generalized additive model (GAM) regression were employed. Subgroup analysis and interaction tests were conducted to explore the stability of this association across different groups.

Results

The final analysis comprised a total of 31,344 participants, including 2,928 individuals who had a history of kidney stones. In the fully adjusted model, an increase in WWI exhibited a positive correlation with the prevalence of kidney stones (OR=1.34, 95% CI: 1.18-1.51). When WWI was converted into quartiles (Q1-Q4), participants in the highest quartile (Q4) had a 69% greater risk of developing kidney stones compared to those in the lowest quartile (Q1) (OR=1.69, 95% CI: 1.28-2.25). This positive association was particularly notable among non-diabetic patients.

Conclusion

Our study demonstrates a significant positive association between weight-adjusted waist index levels and an elevated prevalence of kidney stones among US adults. Furthermore, this research highlights the potential utility of weight-adjusted waist index in the prevention of kidney stones in the overall population. This relationship is limited and further research is needed to test this hypothesis.

Associations between weight-adjusted waist index and bone mineral density: results of a nationwide survey

BACKGROUND

The weight-adjusted waist circumference index (WWI) is a novel obesity indicator that offers improved accuracy in assessing both muscle and fat mass compared to traditional measures. This study aimed to investigate the association between WWI and bone mineral density (BMD) in adults.

METHODS

Weighted multivariate logistic regression, subgroup analysis, interaction tests and restricted cubic spline (RCS) curves were used to explore the relationship between WWI and BMD based on data from the National Health and Nutrition Examination Survey (NHANES).

RESULTS

This study had 40,568 individuals in total. At all four measurement sites, we detected a negative linear correlation between WWI and BMD. Even when quartile factors for WWI were created, this unfavorable connection maintained. In comparison to those in the lowest quartile, those in the highest percentile of WWI showed declines in lumbar BMD of 0.08 g/cm2 and femoral neck BMD of 0.03 g/cm2, respectively. This adverse correlation, nevertheless, differed among several categories.

CONCLUSIONS

Our findings suggest an adverse correlation between WWI and BMD among US adults. Employing WWI as a tool for osteoporosis prevention in the general population may enhance interventions.

Associations between systemic immune-inflammation index and abdominal aortic calcification: Results of a nationwide survey

BACKGROUND AND AIM

The Systemic Immune-Inflammation Index (SII) is a novel index of inflammation assessment that appears to be superior to the common single blood index in the assessment of cardiovascular disease. The purpose of this study was to investigate the association between SII and abdominal aortic calcification (AAC) in adults.

METHODS AND RESULTS

Multivariate logistic regression, sensitivity analysis, and smoothing curve fitting were used to investigate the relationship between SII and AAC based on data from the National Health and Nutrition Examination Survey (NHANES) 2013-2014. Subgroup analysis and interaction tests were used to investigate whether this association was stable across populations. There was a positive association between SII and ACC in 3036 participants >40 years of age. In the fully adjusted model, each 100-unit increase in SII was associated with a 4% increase in the risk of developing severe AAC [1.04 (1.02, 1.07)]. Participants in the highest quartile of SII had a 47% higher risk of developing severe AAC than those in the lowest quartile [1.47 (1.10, 1.99)]. This positive association was more pronounced in older adults >60 years of age.

CONCLUSIONS

SII is positively associated with AAC in US adults. Our findings imply that SII has the potential to improve AAC prevention in the general population.

Association between weight-adjusted-waist index with hepatic steatosis and liver fibrosis: a nationally representative cross-sectional study from NHANES 2017 to 2020

Background

The negative effects of obesity on hepatic steatosis and fibrosis have received considerable attention in recent years. The weight-adjusted-waist index (WWI) reflects weight-independent centripetal obesity. Herein, we provide the first investigation of a link between WWI, hepatic steatosis, and liver fibrosis.

Methods

We used data from the National Health and Nutrition Examination Survey 2017-2020 to conduct a cross-sectional study. The linear relationship between WWI, controlled attenuation parameters, and liver stiffness measurements (LSM) was investigated using multivariate linear regression models. The nonlinear relationship was described using fitted smoothed curves and threshold effect analyses. Subgroup analyses were performed based on gender, age, body mass index, diabetes, hypertension, drinking, and smoking.

Results

This population-based study included 7,594 people, 50.74% of whom were men and 49.26% of whom were women. Multivariate linear regression analysis revealed a significant positive relationship between WWI and hepatic steatosis [CAP, β=7.60, 95% confidence interval (CI) (4.42, 10.78), P<0.0001]. This positive association was stronger when excessive alcohol intake was present compared to when it was absent (P for interaction = 0.031), and when hypertension was present compared to when it was not (P for interaction = 0.014). The linear relationship between WWI and liver fibrosis was not statistically significant on multiple regression analysis [LSM, β=0.03, 95% CI (-0.26, 0.32), P=0.84]. However, a U-shaped association was seen between WWI and LSM, with a negative correlation when WWI< 10.92 and a positive correlation when WWI > 10.92.

Conclusion

We report a strong association between WWI and hepatic steatosis, and suggest that it may potentially be used as a simple anthropometric index to predict hepatic steatosis.

Associations between weight-adjusted waist index and fractures: a population-based study

INTRODUCTION

The weight-adjusted waist circumference index (WWI) is a novel obesity evaluation indicator that appears to be superior to body mass index (BMI) and waist circumference (WC) in evaluating muscle and fat mass. The purpose of this study was to investigate the association between WWI and fractures among adults.

METHODS

In this cross-sectional study, multivariate logistic regression and smoothed curve fitting were used to investigate linear and nonlinear associations between WWI and fractures, based on data from 28,679 adult participants in the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018.

RESULTS

After adjusting for all covariates, the prevalence of hip/wrist/spine fractures among all participants was 1.09%, 8.87%, and 1.97%, respectively. A 1-unit increase in WWI was associated with a 5% increase in the odds of hip fractures [1.05 (1.01, 1.10)], and a 9% increase in the odds of spine fractures [1.09 (1.06, 1.13)], but not with the prevalence of wrist fractures [0.97 (0.94, 1.06)].

CONCLUSIONS

Higher WWI was associated with an increased prevalence of hip fracture and spine fracture, but not wrist fracture.

Weight-Adjusted-Waist Index Predicts Newly Diagnosed Diabetes in Chinese Rural Adults

The relationship between the weight-adjusted waist index (WWI) and newly diagnosed type 2 diabetes (T2D) remains uncertain. This study intended to explore the association between the WWI and the incidence of newly diagnosed T2D among participants in rural areas of China. In the Northeast China Rural Cardiovascular Health Study, 9205 non-diabetic individuals (mean age 53 ± 10, 53.1% women) without T2D were included at baseline during 2012-2013. They were followed up from 2015 to 2017. WWI was calculated as waist circumference (cm) divided by the square root of weight (kg). We used multivariate logistic regression models to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the probability of new diagnoses across three WWI categories. A total of 358 participants had been diagnosed with T2D during a median follow-up of 4.6 years. After adjusting for potential confounders, compared with the lowest WWI category (<9.79 cm/√kg in men; <10.06 in women), men with WWI 10.06-10.72 and ≥10.37 cm/√kg showed OR (95%CI) for T2D 1.200 (0.816, 1.767) and 1.604 (1.088, 2.364), respectively, while women with WWI 10.06-10.72 and ≥10.37 cm/√kg showed ORs (95%CIs) for T2D 1.191 (0.703, 2.018) and 1.604 (1.088, 2.364), respectively. The ORs were generally consistent on subgroup analysis by gender, age, body mass index, and current smoking and drinking status. Increasing WWI was significantly associated with a higher incidence of newly diagnosed T2D among rural Chinese adults. Our findings help clarify the harmful effect of increasing WWI on newly diagnosed T2D and provide evidence for formulating healthcare policy in rural China.