Association between weight-adjusted-waist index and heart failure: Results from National Health and Nutrition Examination Survey 1999-2018

Weight-adjusted waist index as a practical predictor for diabetes, cardiovascular disease, and non-accidental mortality risk

BACKGROUND AND AIM

Identifying a more suitable marker among various measures of adiposity, demonstrating strong associations and predictive ability for clinical use, remains a topic of debate. Weight-adjusted waist index (WWI) has been proposed as a novel index of adiposity, yet its exploration is limited, especially in Chinese populations. This study seeks to examine the associations between body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHTR), weight-adjusted waist index (WWI), waist circumference divided by body mass to the power of 0.333 (WC/M0.333), visceral adiposity index (VAI), lipid accumulation product (LAP), and the incidence of diabetes, cardiovascular disease, and non-accidental mortality in Chinese populations. Furthermore, our goal is to compare the respective predictive values of these measures for these health outcomes.

METHODS AND RESULTS

This prospective cohort study included 21,750 subjects with a 9-year follow-up period. Cox proportional hazard models were used to investigate the relationship between eight anthropometric indexes and the incidence of diabetes, cardiovascular disease, and non-accidental mortality. The predictive value of these eight indexes was compared using the area under the curve metric. Significant positive associations were found between WWI and the risk of diabetes. Using the first quartile (Q1) of WWI as the reference group, hazard ratios with 95% confidence intervals for the risk of diabetes were 1.58 (0.98-2.55) for Q2, 2.18 (1.34-3.35) for Q3, and 2.27 (1.41-3.67) for Q4. Significant associations were observed with the highest quartile of WWI for the risk of cardiovascular disease [Q2: HR 1.45 (95% CI 1.06-1.98); Q3: 1.33 (0.97-1.83); Q4: 1.55 (1.13-2.14)] and risk of non-accidental mortality [Q2: 0.94 (0.80-1.11); Q3: 1.24 (1.04-1.48); Q4: 1.44 (1.16-1.79)]. Receiver operating characteristic analysis revealed that WWI exhibited superior discrimination and accuracy in predicting cardiovascular disease and non-accidental mortality compared to other adiposity indexes (BMI, WC, WHR, WHTR, WC/M0.333, VAI, and LAP).

CONCLUSION

WWI exhibited the most robust and consistent association with the incidence of cardiovascular disease and non-accidental mortality. Given its simplicity and widespread use, WWI emerges as a novel and practical predictor of diabetes, cardiovascular disease, and non-accidental mortality among the eight adiposity indexes investigated in this study.

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.

The association between the weight-adjusted-waist index and frailty in US older adults: a cross-sectional study of NHANES 2007-2018

Objective

This study aimed to evaluate the relationship between the weight-adjusted waist circumference index (WWI) and the frailty in American adults aged over 60 years.

Methods

We utilized data from the National Health and Nutrition Examination Surveys (NHANES) spanning from 2007 to 2018. WWI was calculated using the square root of waist circumference (cm) divided by body weight (kg). The frailty index ≥ 0.25 was employed to assess frailty. Weighted multivariate logistic regression was conducted to explore the association between WWI and frailty. Generalized Additive Modeling (GAM) was used to explore potential non-linear relationships. Receiver operating characteristic curve (ROC) analysis was used to assess the predictive ability of WWI for frailty.

Results

The study encompassed 7765 participants. Higher WWI was significantly associated with higher odds of frailty. In the fully adjusted model, each unit increase of WWI was associated with an 82% increased odds of frailty (OR: 1.82, 95% CI: 1.61 - 2.06; P < 0.001). GAM found significant nonlinear relationships and threshold effects.

Conclusion

The study presented a robust correlation between elevated WWI and increased odds of frailty among American older adults. However, these findings require further validation in large-scale, prospective studies.

Association between the weight-adjusted-waist index and circadian syndrome in findings from a nationwide study

Weight-adjusted-waist index (WWI) is an emerging parameter for evaluating obesity. We sought to ascertain the link between WWI and circadian syndrome (CircS). The study population consisted of 8275 eligible subjects who were included in the ultimate analysis from the NHANES 2011-2018. By using multivariable regression models, the association of WWI and CircS was analyzed. In subgroup analysis, we explored the relationship in different groups and tested the stability of the intergroup connection using interaction testing. To investigate whether WWI and CircS had a potential non-linear relationship, smooth curve fittings, and threshold effects tests were also constructed. In a multivariate linear regression model, WWI is significantly positively related to CircS (OR = 1.77, 95% CI 1.50-2.08). Through subgroup analysis and interaction testing, the stability of this positive association was also validated. It was further found that there was an inverted U-shaped association, with a turning point of 11.84, between WWI and CircS. Our findings supported a strong association between WWI values and CircS. Central obesity management is pivotal for preventing or alleviating CircS.

The association between weight-adjusted waist circumference index and cardiovascular disease and mortality in patients with diabetes

Cardiovascular disease (CVD) is a significant health concern, particularly among patients with diabetes. The weight-adjusted waist circumference index (WWI), a novel metric that accounts for central obesity, has shown potential in predicting obesity-related health risks. This study aimed to evaluate the association of WWI with CVD and mortality in patients with diabetes. Utilizing data from the National Health and Nutrition Examination Survey from 1999 to 2020, WWI was calculated by dividing waist circumference (WC) by the square root of body weight. Multivariate logistic regression, multivariate Cox regression and restricted cubic spline curves were used to assess the association between WWI and the prevalence of CVD and mortality in patients with diabetes, subgroup and sensitivity analyses were carried out to delve into the stability of the findings. The predictive performance of WWI was evaluated using the area under the receiver operating characteristic curve (ROC). This study included 8,005 individuals with diabetes. With the increase in WWI values, the risk of developing CVD and the likelihood of mortality progressively rise. The fully adjusted continuous model indicated a 28% higher chance of developing CVD and a 25% higher risk of all-cause mortality for each one-unit increase in WWI. When using the lowest quartile of WWI as the reference category, the highest quartile was linked to an increased risk of CVD (OR 1.66; 95% CI 1.10-2.50, p = 0.015) and all-cause mortality (HR 1.53, 95% CI 1.27-1.83, p < 0.001) among patients with diabetes. Subgroup and sensitivity analyses confirmed that these associations were consistent and stable in most different demographics. The ROC analysis indicated that WWI had a higher predictive capacity for CVD and all-cause mortality than WC, waist to hip ratio, and weight to height ratio. The WWI was significantly associated with the prevalence of CVD and all-cause mortality among patients with diabetes in the United States and may serve as a useful tool for identifying individuals at risk.

Association of weight-adjusted waist index with cardiovascular disease and mortality among metabolic syndrome population

Metabolic syndrome (MetS) is prevalent and significantly impacts global public health, with obesity being a major risk factor for cardiovascular diseases (CVD) and mortality. Traditional metrics like body mass index (BMI) have limitations in assessing obesity-related risks. The weight-adjusted waist circumference index (WWI) has emerged as a novel obesity metric, this study aimed to evaluate the association of WWI with CVD and mortality in MetS patients. This study used data from 12,641 participants with MetS, derived from the National Health and Nutrition Examination Survey (NHANES) conducted from 1999 to 2020. The WWI was calculated, and its association with CVD and mortality was assessed using multivariate logistic and Cox regression models. The study controlled for potential confounders and performed subgroup and sensitivity analyses to validate the robustness of the findings. The predictive performance of WWI was evaluated using the area under the receiver operating characteristic curve (ROC). Kaplan-Meier (KM) curves further were used to evaluate the associations between WWI and mortality of the MetS population. As WWI values escalated, there was a proportional rise in the risk of CVD and mortality in MetS. The fully adjusted continuous model revealed a 32.0% elevated likelihood of CVD development, a 69.5% increased probability of heart failure (HF), a 51.1% heightened risk for CVD mortality, and a 22.8% augmented risk for all-cause mortality with each one-unit increment in WWI. Comparing the highest to the lowest quartile of WWI, the top quartile exhibited a significantly increased risk of CVD (odds ratio [OR] = 1.883; 95% confidence interval [CI]: 1.276-2.633, p-value = 0.001), HF (OR = 2.909; 95% CI: 1.490-5.677, p-value = 0.002), CVD mortality (hazard ratio [HR] = 2.088; 95% CI: 1.279-3.409, p-value = 0.003), and all-cause mortality (HR = 1.394; 95% CI: 1.070-1.816, p-value = 0.014) among individuals with MetS. Sensitivity and subgroup analyses substantiated the consistency and stability of these associations across various demographic groups. The ROC analysis demonstrated that WWI outperforms BMI in predicting adverse outcomes in MetS. The KM curves validated that higher WWI values was correlated with diminished survival rates in MetS population. The WWI served as a significant indicator for assessing the risk of CVD and mortality in the MetS population. This study recommended the regular assessment of WWI in MetS individuals for evaluating their risk of CVD and mortality, potentially enhancing preventive and treatment strategies for this patient 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.

The weight-adjusted waist index and frailty: A cohort study from the China Health and Retirement Longitudinal Study

OBJECTIVES

This cohort study's aim was to assess the association between the weight-adjusted waist index (WWI) and frailty among middle-aged and elderly individuals in China.

METHODS

Seven-year complete follow-up data from 10,349 adults aged ≥45 years, initially surveyed in 2 011 in the China Health and Retirement Longitudinal Study, were analyzed, including clinical demographic characteristics, anthropometric indices, frailty scores, and relevant covariates. The WWI was calculated as waist circumference divided by the square root of the body weight. Frailty was evaluated using the Frailty Index. Relationships between the WWI and frailty were evaluated via Cox proportional hazards modeling. Receiver operating characteristic curve analyses assessed the effectiveness of obesity-related indicators in predicting frailty.

RESULTS

Over a median 84-month follow-up period, frailty occurred in 23.7% (2453/10,349) of participants. After potential confounder adjustment, the WWI positively correlated with frailty (adjusted hazard ratio: 1.14; 95% confidence interval: 1.08-1.20; p < 0.001). After WWI-stratification into quartiles based on frailty and covariate adjustment, regression analyses were conducted; the adjusted hazard ratios exhibited a significant upward trend (p < 0.001). The subgroup analyses revealed higher positive correlations between the WWI and frailty in males and those aged ≥65 years and lower correlations in those with a high school or higher educational level and in married or cohabiting individuals. The strong positive correlation was unaltered in the other subgroup analyses. The WWI outperformed all other obesity-related indicators as a frailty predictor.

CONCLUSIONS

The WWI is a dependable and innovative obesity-related predictor of frailty and could help in mitigating its development.

J-Shaped Relationship Between Weight-Adjusted-Waist Index and Cardiovascular Disease Risk in Hypertensive Patients with Obstructive Sleep Apnea: A Cohort Study

Background

A newly introduced obesity-related index, the weight-adjusted-waist index (WWI), emerges as a promising predictor of cardiovascular disease (CVD). Given the known synergistic effects of hypertension and obstructive sleep apnea (OSA) on cardiovascular risk, we aimed to explore the relationship between the WWI and CVD risk specifically within this high-risk cohort.

Methods

A total of 2265 participants with hypertension and OSA were included in the study. Multivariate Cox regression analysis was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for CVD events. The restricted cubic spline (RCS) was used to further evaluate the nonlinear dose-response relationship.

Results

During a median follow-up period of 6.8 years, 324 participants experienced a CVD event. Multivariate Cox regression analysis revealed that compared to the reference group, the HRs for the second, third, and fourth groups were 1.12 (95% CI, 0.79-1.59), 1.35 (95% CI, 0.96-1.89), and 1.58 (95% CI, 1.13-2.22), respectively. Moreover, RCS analysis illustrated a clear J-shaped relationship between the WWI and CVD risk, particularly notable when WWI exceeded 11.5 cm/√kg, signifying a significant increase in CVD risk.

Conclusion

There was a J-shaped relationship between WWI and CVD in hypertensive patients with OSA, especially when the WWI was greater than 11.5 cm/√kg, the risk of CVD was significantly increased.

Association between weight-adjusted-waist index and cognitive decline in US elderly participants

Objective

To investigate the association between the weight-adjusted-waist index (WWI) and cognitive decline in elderly Americans from 2011 to 2014.

Methods

A cross-sectional study was conducted on 2,762 elderly participants from the National Health and Nutrition Examination (NHANES) between 2011 and 2014. WWI was calculated by dividing waist circumference (cm) by the square root of body weight (kg). Participants assessed their cognitive functions using tests such as the DSST, AFT, and CERAD W-L. In this research, multiple logistic regression, HIA, limited cubic spline (RCS), and threshold effect analysis methods were utilized to explore the relationship between cognitive decline and WWI.

Results

The study involved 2,762 participants aged 60 years and older, comprising 1,353 males (49%) and 1,409 females (51%), with a median age of 69.3 years (standard deviation = 6.7). The analysis revealed that the risk of cognitive decline was positively associated with the WWI. Fully adjusted models indicated significant correlations with the CERAD W-L [odds ratio (OR) = 1.24, 95% confidence interval (CI) = 1.06-1.46, p < 0.008], AFT (OR = 1.27, 95% CI = 1.08-1.49, p = 0.003), and DSST (OR = 1.56, 95% CI = 1.29-1.9, p < 0.001). Subgroup analysis demonstrated a consistent relationship across different population settings except for gender (average of interactions, p > 0.05). A J-shaped relationship between WWI and low DSST scores was observed using multivariate restricted cubic spline (RCS) regression (P for non-linearity <0.05), with the curve steepening when WWI ≥ 12.21 cm/√kg. Additionally, the study found that WWI was more strongly associated with an increased risk of cognitive decline than other obesity indicators such as Body Mass Index (BMI), waist circumference (WC), and A Body Shape Index (ABSI).

Conclusion

Our data have shown a significant positive association between the WWI and a higher risk of cognitive decline in older Americans, with a J-shaped non-linear relationship between WWI and DSST. In addition, our findings indicate that WWI was associated with greater cognitive decline than other markers of obesity.

Association between weight-adjusted-waist index and depression: a cross-sectional study

Background

Depression has become a multifaceted global health issue, with complex connections to obesity. Weight-adjusted-waist index (WWI) can effectively evaluate central obesity, but the relationship between WWI and depression has not been well studied. The study aims to investigate the potential correlation between these two health parameters.

Methods

According to the data from National Health and Nutrition Examination Survey, this cross-sectional study used multiple regression analysis, subgroup analysis, and smooth curve fitting to explore the relationship between WWI and depression. The assessment ability of WWI was evaluated and compared to other obesity indicators using the receiver operating characteristic (ROC) curve.

Results

This study analyzed 38,154 participants. Higher WWI is associated with higher depression scores (β = 0.41; 95% CI, 0.36-0.47). After adjusting for various confounding factors, the positive correlation between WWI and depression remained significant (P for trend < 0.0001). Nonlinear positive correlation was detected with a breakpoint of 11.14. ROC analysis shows that compared to other obesity indicators (ROCWWI = 0.593; ROCBMI = 0.584; and ROCWC = 0.581), the correlation between WWI and depression has better discrimination and accuracy. DII mediated 4.93%, SII mediated 5.08%, and sedentary mediated 0.35% of the total association between WWI and depression.

Conclusion

WWI levels were related to an increased likelihood of depression and showed a stronger relationship than BMI and waist circumference. Our findings indicated that WWI may serve as a simple anthropometric index to evaluate depression.

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.

Association between weight-adjusted waist index and non-alcoholic fatty liver disease: a population-based study

BACKGROUND

Obesity is the most important driver of non-alcoholic fatty liver disease (NAFLD); nevertheless, the relationship of weight-adjusted waist index (WWI), a new obesity index, with NAFLD is unclear.

METHODS

This retrospective study used data from the NAGALA project from 1994 to 2016. WWI values were calculated using waist circumference (WC) and weight measurements of the participants. Three stepwise adjusted logistic regression models were developed to assess the relationship of WWI with NAFLD in the whole population and in both sexes. Additionally, we also conducted a series of exploratory analysis to test the potential impact of body mass index (BMI), age, smoking status and exercise habits on the association of WWI with NAFLD. Receiver operating characteristic (ROC) curves were used to estimate cut-off points for identifying NAFLD in the entire population and in both sexes.

RESULTS

The current study included a population of 11,805 individuals who participated in health screenings, including 6,451 men and 5,354 women. After adjusting for all non-collinear variables in the multivariable logistic regression model, we found a significant positive correlation of WWI with NAFLD. For each unit increase in WWI, the risk of NAFLD increased by 72% in the entire population, by 84% in men, and by 63% in women. Furthermore, subgroup analyses revealed no significant discrepancies in the correlation of WWI with NAFLD across individuals with varying ages, exercise habits, and smoking status (all P-interaction > 0.05), except for different BMI groups (P-interaction < 0.05). Specifically, compared to the overweight/obese group, the relationship of WWI with NAFLD was significantly stronger in the non-obese group, especially in non-obese men. Finally, based on the results of ROC analysis, we determined that the WWI cut-off point used to identify NAFLD was 9.7675 in men and 9.9987 in women.

CONCLUSIONS

This study is the first to establish a positive correlation between WWI and NAFLD. Moreover, assessing the influence of WWI on NAFLD in individuals without obesity may yield more valuable insights compared to those who are overweight or obese.

Association between weight-adjusted-waist index and gallstones: an analysis of the National Health and Nutrition Examination Survey

BACKGROUND

The weight-adjusted-waist index (WWI) is a novel obesity index, and gallstones are associated with obesity. This study aimed to investigate the possible relationship between WWI and gallstones.

METHODS

The datasets from the National Health and Nutrition Examination Survey (NHANES) 2017-2020 were used in a cross-sectional investigation. Multivariate linear regression models were used to examine the linear connection between WWI and gallstones incidence. Fitted smoothing curves and threshold effect analysis were used to describe the nonlinear relationship.

RESULTS

The study comprised 8004 participants over the age of 20, including 833 reported with gallstones. Participants in the higher WWI tertile tended to have a higher gallstones prevalence. In the final adjusted model, a positive association between WWI and gallstones prevalence was observed (OR = 1.34, 95% CI: 1.20‒1.49). Participants in the highest WWI tertile had a significantly 71% higher risk of gallstones than those in the lowest WWI tertile (OR = 1.71, 95% CI: 1.35‒2.17). A nonlinear correlation was found between the WWI and gallstones prevalence, with an inflection point of 12.7.

CONCLUSIONS

Our study found that higher WWI levels connected with increased prevalence of gallstones. However, more prospective studies are needed to validate our findings.

Association between the weight-adjusted waist index and the odds of type 2 diabetes mellitus in United States adults: a cross-sectional study

Objective

To examine the association between the weight-adjusted waist index (WWI) and the odds of type 2 diabetes mellitus(T2DM)among U.S. adults.

Methods

Data from the National Health and Nutrition Examination Survey (NHANES) spanning six years (2007-2018) were utilized, encompassing 31001 eligible participants. Weighted multivariate logistic regression models and smoothed fit curves were employed to assess the association between WWI and the odds of T2DM, as well as dose-response relationships in the overall population and the odds of T2DM in various subgroups.

Results

In the fully adjusted continuous model, each one-unit increase in WWI was associated with a 1.14-fold increase in the odds of T2DM within the entire study population (2.14 [1.98,2.31], P < 0.0001). In the fully adjusted categorical model, when using the lowest tertile of WWI (T1) as the reference group, the second tertile (T2) and the third tertile (T3) were associated with a 0.88-fold (1.88 [1.64,2.17], P < 0.0001) and a 2.63-fold (3.63 [3.11,4.23], P < 0.0001) increase in the odds of T2DM. These findings indicated a positive correlation between WWI values and the odds of T2DM, aligning with the results of the smoothed-fitted curves. In the analysis of subgroups, in addition to maintaining consistency with the overall population results, we found interactions between age and hypertension subgroups.

Conclusion

In conclusion, WWI was found to be positively associated with the odds of T2DM in U.S. adults.

Significance of fatty liver index to detect prevalent ischemic heart disease: evidence from national health and nutrition examination survey 1999-2016

Background

Non-alcoholic fatty liver disease (NAFLD) contributes to the development of ischemic heart disease via multiple mechanisms. Fatty liver index (FLI) has been proposed as an accurate, convenient, and economic surrogate of the severity of NAFLD. Our present study aims to assess the association between FLI and the prevalent IHD and to evaluate the potential value of FLI to refine the detection of prevalent IHD in the general population.

Methods

Our work recruited 32,938 subjects from the National Health and Nutrition Examination Survey 1999-2016. IHD was diagnosed according to the subjects' self-report. FLI was determined based on triglycerides, BMI, γ-glutamyltransferase, and waist circumference.

Results

2,370 (7.20%) subjects were diagnosed with IHD. After adjustment of age, sex, race, current smoking, current drinking, PIR, BMI, WC, TC, TG, GGT, Scr, FPG, SBP, anti-hypertensive therapy, anti-diabetic therapy, and lipid-lowering therapy, one standard deviation increase of FLI resulted in a 27.0% increment of the risk of prevalent IHD. In the quartile analysis, we observed a 1.684 times risk of prevalent IHD when comparing the fourth quartile with the first quartile, and there was a trend towards higher risk across the quartiles. The smooth curve fitting displayed a linear relationship between FLI and the presence of IHD without any threshold or saturation effect. Subgroup analysis revealed a robust association in conventional cardiovascular subpopulations, and the association could be more prominent in female subjects and diabetes patients. ROC analysis demonstrated an incremental value of FLI for detecting prevalent IHD after introducing it to conventional cardiovascular risk factors (AUC: 0.823 vs. 0.859, P for comparison <0.001). Also, results from reclassification analysis implicated that more IHD patients could be correctly identified by introducing FLI into conventional cardiovascular risk factors (continuous net reclassification index: 0.633, P < 0.001; integrated discrimination index: 0.034, P < 0.001).

Conclusion

The current analysis revealed a positive and linear relationship between FLI and the prevalent IHD. Furthermore, our findings suggest the incremental value of FLI to refine the detection of prevalent IHD in the general population.

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.

Association between the weight-adjusted waist index and stroke: a cross-sectional study

BACKGROUND

The weight-adjusted waist index (WWI) is a new measure of obesity, and this study aimed to determine the association between the WWI and stroke.

METHODS

Using the National Health and Nutrition Examination Survey (NHANES) 2011-2020 dataset, cross-sectional data from 23,389 participants were analysed. The correlation between the WWI and stroke was investigated through multivariate logistic regression and smoothing curve fitting. Subgroup analysis and interaction tests were also carried out.

RESULTS

The research involved 23,389 participants, of whom 893 (3.82%) had a stroke. The fully adjusted model revealed a positive correlation between the WWI and stroke [1.25 (1.05, 1.48)]. Individuals who were in the highest quartile of WWI exhibited a 62% higher likelihood of experiencing a stroke than those in the lowest quartile [1.62 (1.06, 2.48)]. Subgroup analysis and interaction tests revealed that this positive correlation was similar in different population settings (all P for interaction  > 0.05).

CONCLUSION

A higher WWI was associated with a higher prevalence of stroke. The results of this study underscore the value of the WWI in stroke prevention and management.

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.

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.

The association between weight-adjusted-waist index and total bone mineral density in adolescents: NHANES 2011-2018

Introduction

The weight-adjusted waist index (WWI) serves as an innovative obesity measure, seemingly surpassing body mass index (BMI) and waist circumference (WC) in evaluating lean and fat mass. This study aimed to explore the relationship between WWI and total bone mineral density (BMD) in US adolescents.

Methods

This population-based study investigated adolescents aged 8-19 years with comprehensive WWI and total BMD data from the National Health and Nutrition Examination Survey (NHANES) 2011-2018. WWI was computed by dividing WC by the square root of body weight. Weighted multivariate linear regression and smoothed curve fitting were employed to examine linear and non-linear associations. Threshold effects were determined using a two-part linear regression model. Additionally, subgroup analyses and interaction tests were conducted.

Results

Multivariate linear regression analysis revealed a significant negative association between WWI and total BMD in 6,923 US adolescents aged 8-19 years [β = -0.03, 95% CI: (-0.03, -0.03)]. This negative correlation remained consistent across all subcategories, with the exception of age, encompassing gender,ethnicity, and diabetes status subgroups. Furthermore, a non-linear relationship and saturation effect between WWI and total BMD were identified, with an inflection point at 9.88 cm/√kg.

Conclusions

Our research demonstrated a notable negative relationship and saturation effect between WWI and total BMD among US adolescents.

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.