Body Mass Index and Mortality in the General Population and in Subjects with Chronic Disease in Korea: A Nationwide Cohort Study (2002-2010)

Dietary Habits, Anthropometric Values, and Microvascular Reactivity in Older Persons of Both Sexes Living at Retirement Home in Osijek, Croatia

Purpose

To examine the correlation between dietary habits, anthropometric measurements, and microvascular reactivity with respect to sex in older adults (aged > 65 years) residing in organized accommodation within retirement homes.

Patients and Methods

Sixty-nine older persons who live in a retirement home in Osijek, Croatia volunteered to participate (34 men and 35 women) in this observational cross-sectional study. Study was performed in the period from May 1, 2024 to July 1, 2024. Subjects weight, height, waist circumference, hip circumference, blood pressure and heart rate were measured, and body mass index (BMI) and waist to hip ratio (WHR) were calculated. To assess microvascular endothelium-dependent vasodilation, skin microvascular post-occlusion reactive hyperemia (PORH) was assessed by Laser Doppler Flowmetry. Long-term dietary patterns and dietary habits were evaluated with validated EPIC-Norfolk food frequency questionnaire, in Croatian language. Study was approved by Ethical Committee of Faculty of Medicine Osijek (Class: 641-01/24-01/04, No: 2158-61-46-24-86).

Results

Mean age (standard deviation, SD) of 34 older men was 83.8 (5.4) years, and of 34 older women 83.6 (5.5) years. The mean BMI of all subjects was 27.1 kg/m2 classifying them as overweight. Both men (WHR 0.99 (0.07)) and women (WHR 0.90 (0.06) had significantly higher than normal WHR (normal WHR, men <0.90, women <0.80), suggesting the visceral type of obesity. The mean intake of NaCl was higher (NaCl g/day men 6.91 (1.43), women 6.93 (2.51)), and intake of vitamin D lower (vitamin D µg/day men 3.64 (1.35), women 3.47 (2.61)) than recommended values (NaCl g/day <5 g/day, vitamin D 15 µg/day). Men consumed significantly more alcohol (alcohol g/day men 1.48 (3.36) vs women 0.17 (0.39), P = 0.03), while women had higher carotene intake (β-carotene, µg/day men 2603 (1020) vs women 3478 (1580), P = 0.009). Microvascular reactivity was similar in women and men (PORH, R-O% men 85.2 (30.6) vs women 76.2 (31.5), P > 0.05). However, women had a significant negative correlation of waist circumference (R = -0.350, P =0.04) and WHR (R = -0.406, P = 0.02) to PORH.

Conclusion

Dietary habits were similar between older men and women, except for higher alcohol intake in men and higher carotene intake in women. In older women, microvascular reactivity was negatively associated with waist circumference and WHR, underscoring central obesity as a key cardiovascular risk factor in this population. Given the increased cardiometabolic vulnerability in postmenopausal women, measures of central adiposity should be routinely monitored in geriatric care.

Association between the weight-adjusted waist index and age-related macular degeneration in US adults aged≥40 years: the NHANES 2005-2008

Objective

The association between the weight-adjusted waist index (WWI) and age-related macular degeneration (AMD) in US adults aged 40 years and older is unknown. The goal of this study was to ascertain a possible association between the two.

Methods

Data were obtained from the National Health and Nutrition Examination Survey (NHANES) in the US from 2005 to 2008. The WWI was calculated by dividing waist circumference (WC) by the square root of body weight (kg). AMD was diagnosed based on distinctive features observed in the fundus, using a standard classification system. Weighted logistic regression analyses were conducted to investigate the association between the WWI and AMD. Spline smoothing and threshold effects were applied to explore non-linear correlations. Subgroup analyses were performed to identify underlying covariates affecting this relationship. In addition, receiver operating characteristic (ROC) curve analysis was used to evaluate the predictive power of the WWI for AMD.

Results

A total of 5,132 participants were enrolled in this study. The results showed a significant positive association between the WWI and risk of AMD (OR = 1.76 (1.52, 2.04); p < 0.0001). When the WWI was categorized into tertiles, the highest group exhibited a stronger association compared to the lowest tertile (OR = 2.90 (2.18, 3.86); p < 0.0001) in model 1. The subgroup analyses and interaction tests indicated that the relationship between the WWI and AMD was stable across various populations. The spline smoothing and threshold effects showed a positive non-linear correlation between the WWI and AMD incidence. Furthermore, compared to body mass index (BMI), WC, and weight, the WWI showed better predictability for AMD, as shown by the ROC analysis.

Conclusion

There exists a positive non-linear association between the WWI and AMD in US adults aged 40 years and older. The WWI-related obesity management is necessary for the prevention and treatment of AMD.

Correlation between weight-adjusted waist index and coronary heart disease: NHANES 1999-2020

Background

The weight adjusted waist index (WWI) represents a novel indicator for assessing central obesity. The objective of this study is to investigate the association between WWI and coronary heart disease (CHD).

Method

The data of 44,528 participants in total were gathered from NHANES database from 1999 to 2020. WWI is calculated as the waist circumference (WC, cm) divided by the square root of the body weight (kg), and CHD was determined based on participants' self-reports. The association between WWI and CHD was examined using multiple logistic regression analysis, restrictive cubic spline (RCS), receiver operating characteristic (ROC) curve, mediation analysis, subgroup and interaction analyses.

Result

This was a cross-sectional investigation. A total of 44,528 participants were included [50.23% male; mean WWI 10.89 (0.01) cm/√kg]. The multivariate logistic regression analysis revealed that in three models, one-standard-deviation increment in WWI was associated with an increased probability of CHD occurrence by 2.39 (2.22,2.57),1.47 (1.32,1.65), and 1.15 (1.00,1.32) times, respectively. Additionally, RCS analysis indicated a linear relationship between WWI and CHD. and the ROC analysis results showed that the discriminatory power of WWI for CHD was superior to that of body mass index (BMI) and WC. Glycated hemoglobin (HbA1c) partially mediated the relationship between WWI and CHD. Subgroup and interaction analyses confirmed that age, systolic blood pressure, and diabetes status had a significant impact on the association between WWI and CHD (P for interaction <0.05).

Conclusion

The level of WWI has been demonstrated to be associated with an increased risk of CHD. Specifically, as WWI increases, the risk of CHD becomes higher. On this basis, it is hypothesized that WWI may potentially serve as an independent risk factor for CAD, thereby highlighting the substantial value of WWI in the identification and management of CHD.

Weight-adjusted waist index predicts metabolic syndrome in Caucasian patients with obesity

Introduction

Background and aims: the usefulness of the weight-adjusted waist index (WWI) among persons with metabolic syndrome (MS) has not been previously evaluated. The objective of this study was to evaluate the ability of WWI to predict MS in a Caucasian population with obesity. Methods: we conducted a cross sectional study in 2162 Caucasian patients with obesity. Anthropometric data (weight, height, body mass index [BMI], waist circumference, [WWI]), bioimpedanciometer parameters (total fat mass [FM], skeletal muscle mass [SMM] and skeletal muscle mass index [SMMi]), blood pressure, presence of MS and biochemical parameters were recorded and compared by tertiles of WWI. Results: a total of 1,176 subjects had MS (54.4 %) and 986 did not show MS (45.6 %). Compared with the lowest WWI category Q1 (< 11.24 cm/√kg), the prevalence of MS increased in the logistic regression model adjusted by sex and age in the Q3 group (OR = 2.53, 95 % CI = 1.71-3.23; p = 0.001). In addition, the prevalence of MS was higher in the Q3 group than in Q2 (OR = 1.65, 95 % CI = 1.25-2.17; p = 0.005). Finally, the prevalence of MS in Q2 was higher than in the Q1 group (OR = 1.21, 95 % CI = 1.06-3.11; p = 0.01). The area under the curve (AUC) to assess the ability of WWI to identify MS showed values of 0.811 (0.687-0.871; p = 0.001). The cut-off point according to the Youden index was 11.59, with sensitivity and specificity of 70 % and 93.4 %, respectively. Conclusion: we described a good accuracy of WWI to identify MS an independent association between WWI in Caucasian patients with obesity.

Survival benefit of metformin use according to cancer diagnosis in diabetic patients with metabolic syndrome

Background

Metabolic syndrome (MetSyn) is a disease cluster causing cardiovascular disease, cancer, and high mortality. Metformin is the most common antidiabetic agent inhibiting the tumorigenesis and insulin resistance of MetSyn. We describe the association between metformin intake and survival of patients with type 2 diabetes mellitus (T2DM) and MetSyn, according to the presence of cancer.

Methods

We analyzed the clinical characteristics and all-cause mortality of patients with T2DM and MetSyn using a 5-year dataset between January 1, 2009 and December 31, 2013 derived from the Korean National Health Insurance Service-National Health Screening Cohort (NHIS-HEALS). Cox proportional hazards regression models were used to investigate metformin effects adjusted for other potential confounding variables.

Results

Among a total of 43,043 patients with both MetSyn and T2DM, 24,725 patients (57.4 %) received metformin regularly. Female sex, high income, regular exercise, and metformin use were good prognostic factors, whereas hypertension, current smoking, cancer, and diabetes medication (except metformin) were poor prognostic factors. After adjustment for possible confounding variables, metformin showed a significant effect on patient survival (hazard ratio [HR], 0.68; 95 % confidence interval [CI], 0.63-0.75; p < 0.001). The effect of metformin was pronounced on the group of patients with liver, lung, colorectal, or prostate cancers (HR, 0.57; CI, 0.46-0.70).

Conclusions

Metformin intake may be related to favorable survival among patients with T2DM and MetSyn. The efficacy might be more remarkable in those with liver, lung, colorectal, and prostate cancers. The potential benefit of metformin in patients with these risk factors should be further investigated.

Association of systemic immune-inflammation index with all-cause and cardio-cerebrovascular mortality in individuals with diabetic kidney disease: evidence from NHANES 1999-2018

Background

Emerging evidence suggests a potential role of immune response and inflammation in the pathogenesis of diabetic kidney disease (DKD). The systemic immune-inflammation index (SII) offers a comprehensive measure of inflammation; however, its relationship with the prognosis of DKD patients remains unclear.

Methods

Using data from the National Health and Nutrition Examination Survey (NHANES) spanning 1999 to 2018, this cross-sectional study involved adults diagnosed with DKD. Cox proportional hazards models were utilized to assess the associations between SII and all-cause or cardio-cerebrovascular disease mortality. Additionally, restricted cubic spline, piecewise linear regression, and subgroup analyses were performed.

Results

Over a median follow-up duration of 6.16 years, 1338 all-cause deaths were recorded. After adjusting for covariates, elevated SII levels were significantly associated with increased risks of all-cause and cardio-cerebrovascular disease mortality. Specifically, per one-unit increment in natural log-transformed SII (lnSII), there was a 29% increased risk of all-cause mortality (P < 0.001) and a 23% increased risk of cardio-cerebrovascular disease mortality (P = 0.01) in the fully adjusted model. Similar results were observed when SII was analyzed as a categorical variable (quartiles). Moreover, nonlinear association was identified between SII and all-cause mortality (P < 0.001) through restricted cubic spline analysis, with threshold value of 5.82 for lnSII. The robustness of these findings was confirmed in subgroup analyses. Likewise, the statistically significant correlation between SII levels and cardio-cerebrovascular disease mortality persisted in individuals with DKD.

Conclusion

Increased SII levels, whether examined as continuous variables or categorized, demonstrate a significant association with elevated risks of all-cause and cardio-cerebrovascular disease mortality among DKD patients. These findings imply that maintaining SII within an optimal range could be crucial in reducing mortality risk.

Correlation of weight-adjusted waist index with diabetic retinopathy in US adults aged ≥ 40 years: the NHANES 2005-2008

The effect of obesity on diabetic retinopathy (DR) has been under scrutiny in recent years. The weight-adjusted waist index (WWI) has been reported to better assess the degree of centripetal obesity in humans, with a higher WWI indicating a higher amount of body fat. The present study is the first to investigate the relationship between WWI and DR and to assess the difference in the predictive ability of WWI and other obesity indices for DR. This cross-sectional study utilized data from the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2008. Researchers collected complete anthropometric data (weight and waist circumference), dilated fundus images, and adult baseline information. Independent interactions between WWI and DR were investigated using multivariate regression and subgroup analyses. In addition, nonlinear associations and threshold effects between WWI and DR were searched for by smoothed curve fitting and by two-stage linear regression modeling. Finally, the receiver operating characteristic curve (ROC) was plotted to compare the predictive power of WWI with other indices of obesity for DR. A total of 1228 eligible patients with diabetes were collected in this study. There were 631 (51.38%) males and 597 (48.62%) females. Among them, 545 (44.38%) were without diabetic retinopathy, 555 (45.20%) had mild diabetic retinopathy, 100 (8.14%) had moderate/severe diabetic retinopathy and 28 (2.28%) had proliferative diabetic retinopathy (PDR). In the fully adjusted model, each unit increase in WWI was associated with a corresponding 31% reduction in the prevalence of DR [OR (95% CI) = 0.69 (0.58, 0.83)]. Compared with subjects in the lowest quartile (quartile 1), subjects in the highest quartile of WWI levels (quartile 4) were 45% less likely to have DR [OR (95% CI) = 0.55 (0.38, 0.78)]. In the case of female participants, a U-shaped correlation was observed between WWI and DR with an inflection point of 11.49. WWI also possesses a better predictive ability for DR compared to obesity indicators such as weight, BMI, and ABSI. This study showed a negative association between WWI and DR in the U.S. population aged 40 years and older.

An analysis of protective health behavior and polypharmacy among older patients: a nationwide cohort study

BACKGROUND

This study analyzed the relationship between protective health behaviors and polypharmacy in individuals aged 65 years and older.

METHODS

We used data from a nationwide survey (KNHANES) from 2012 to 2016 in conjunction with the health insurance claims databases. A total of 3297 adults aged 65 or older were included in the study. Polypharmacy was defined as more than 30 prescription days in 6 months with five or more different drugs. Health-related behaviors (BMI, smoking, drinking, regular walking, and living alone) were extracted for 6 months before measuring polypharmacy. We used multivariable logistic regression on polypharmacy for each protective health behavior, as well as a composite score of protective health behavior. Subgroup analysis was also conducted by age and sex.

RESULTS

Among protective health behaviors, BMI < 25 (OR, 0.76; 95% CI, 0.66-0.88) and never smoking (OR, 0.78; 95% CI, 0.62-0.98) were associated with a lower risk of polypharmacy. Polypharmacy was significantly associated with BMI < 25 in both sex subgroups (male: OR, 0.71; 95% CI, 0.56-0.88; female: OR, 0.81; 95% CI, 0.67-0.99) and 65-79 subgroup (OR, 0.74; 95% CI, 0.63-0.86). The association between never smoking and polypharmacy was only significant in the 65-79 subgroup (OR, 0.71; 95% CI, 0.55-0.91). Participants with five protective health behaviors had a lower risk of polypharmacy than participants with zero or one health behavior, which was only statistically significant in the subgroup analysis of participants aged 65-79 years (OR, 0.52; 95% CI, 0.29-0.94).

CONCLUSIONS

This study finds that health behaviors such as obesity and smoking are associated with a higher risk of polypharmacy. Furthermore, we confirm that a high score of protective health behaviors is associated with a lower risk of polypharmacy. Our findings indicate the need for geriatric-centered management of protective health behaviors to prevent polypharmacy.

Association between weight-adjusted waist index and risk of diabetes mellitus type 2 in United States adults and the predictive value of obesity indicators

BACKGROUND

The weight-adjusted waist index (WWI) is a quantitative anthropometric index that can be applied to evaluate obesity. This study examined the relationship between adult United States (US) residents' risk of diabetes mellitus type 2 (T2DM) and WWI.

METHODS

The NHANES (National Health and Nutrition Examination Survey) 2001-2018 provided the data for this investigation. This study used multifactorial logistic regression analysis, smoothed curve fitting, subgroup analysis, and interaction tests to assess the association between WWI and T2DM. Additionally, threshold effects were calculated using a two-stage linear regression model. The receiver operating characteristic(ROC) curves evaluated the diagnostic ability of the WWI and commonly used obesity indicators.

RESULTS

20,477 participants were enrolled in the analysis, and patients with greater levels of WWI had a higher prevalence of T2DM. WWI and T2DM have a non-linear relationship, with a positive association found on the left side of the breakpoint (WWI = 12.35) (OR = 1.82, 95%CI:1.64-2.02), whereas, on the right side, no such relationship was found (OR = 0.9, 95%CI:0.61-1.34). For every unit rise in WWI, the probability of having T2DM increased by 67% after controlling for all other variables (OR:1.67,95%CI:1.53-1.83). Based on subgroup analyses, individuals under 40 had a higher correlation between WWI and T2DM (P < 0.001).ROC analyses showed that WWI had the best discrimination and accuracy in predicting T2DM compared to other obesity indicators (WC, BMI, and Weight).

CONCLUSION

Higher WWI values had a higher prevalence of T2DM in US individuals, especially in adults under 40. WWI has the strongest ability to predict T2DM. Therefore, the importance of WWI in the early identification of T2DM in US adults should be emphasized.

Life Expectancy of Patients Undergoing Total Knee Arthroplasty: Comparison With General Population

BACKGROUND

This study aimed to analyze the life expectancy and cause of death in osteoarthritis (OA) patients who underwent total knee arthroplasty (TKA) and to identify risk factors that affect long-term mortality rate after TKA.

METHODS

Among 601 patients, who underwent primary TKA due to OA by a single surgeon from July 2005 to December 2011, we identified patients who died after the operation using data obtained from the National Statistical Office of Korea. We calculated 5-, 10-, and 15-year survival rates of the patients and age-specific standardized mortality ratios (SMRs) compared to general population of South Korea according to the causes of death. We also identified risk factors for death.

RESULTS

The 5-year, 10-year, and 15-year survival rates were 94%, 84%, and 75%, respectively. The overall age-specific SMR of the TKA cohort was lower than that of the general population (0.69; P < 0.001). Cause-specific SMRs for circulatory diseases, neoplasms, and digestive diseases after TKA were significantly lower than those of the general population (0.65, 0.58, and 0.16, respectively; all P < 0.05). Male gender, older age, lower body mass index (BMI), anemia, and higher Charlson comorbidity index (CCI) were significant factors associated with higher mortality after TKA.

CONCLUSION

TKA is a worthwhile surgery that can improve life expectancy, especially from diseases of the circulatory system, neoplasms, and digestive system, in patients with OA compared to the general population. However, careful follow-up is needed for patients with male gender, older age, lower BMI, anemia, and higher CCI, as these factors may increase long-term mortality risk after TKA.

LEVEL OF EVIDENCE

III.

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 weight-adjusted-waist index and risk of cardiovascular diseases in United States adults: a cross-sectional study

BACKGROUND

As a new obesity-related index, the weight-adjusted-waist index (WWI) appears to be a good predictor of cardiovascular disease (CVD) in East Asian populations. This study aimed to validate the association between WWI and CVD in United States (US) adults and also evaluate its relationships with the prevalence of specific CVDs.

METHODS

The data were obtained from the 2009-2016 National Health and Nutrition Examination Survey. WWI was calculated as waist circumference divided by the square root of weight, and CVD was ascertained based on self-reported physician diagnoses. Multivariable logistic regression models and subgroup analyses were performed to evaluate the association between WWI and CVD.

RESULTS

A total of 21,040 participants were included. There was a positive linear relationship between WWI and the odds of CVD (P = 0.310). After adjusting for all covariates, each unit of increased WWI was associated with 48% increased risk of CVD (odds ratio [OR]: 1.48, 95% confidence interval [CI]: 1.25-1.74). Moreover, compared with the lowest quintile (< 10.3 cm/√kg), the multivariable-adjusted OR was 3.18 (95% CI: 1.80-5.59) in the highest quintile (≥ 11.8 cm/√kg). Besides, positive associations were also found between WWI and increased prevalence of congestive heart failure (OR: 1.47, 95% CI: 1.11-1.96), coronary heart disease (OR: 1.27, 95% CI: 1.01-1.60), angina (OR: 1.44, 95% CI: 1.06-1.96), heart attack (OR: 1.66, 95% CI: 1.29-2.12), and stroke (OR: 1.32, 95% CI: 1.02-1.70). Subgroup analyses showed that stronger associations between WWI and CVD were detected in participants younger than 50 years of age (P < 0.001).

CONCLUSIONS

High levels of WWI were significantly associated with an increased risk of CVD in US adults, particularly in people under 50 years of age. These findings indicate that WWI may be an intervention indicator to reduce the risk of CVD in the general adult population.

Lower alanine aminotransferase levels are associated with increased all-cause and cardiovascular mortality in nonalcoholic fatty liver patients

BACKGROUND

Serum alanine aminotransferase (ALT) levels are often considered a marker to evaluate liver disease and its severity.

AIM

To investigate the association between ALT levels and all-cause and cause-specific mortality in patients with nonalcoholic fatty liver disease (NAFLD).

METHODS

The Third National Health and Nutrition Examination Survey (NHANES-III) from 1988 to 1994 and NHANES-III-related mortality data from 2019 onward were used to obtain the necessary data for the study. NAFLD was defined as hepatic steatosis, as diagnosed by ultrasound, with no other liver diseases. ALT levels were categorized into four groups according to the different recommended upper limits of normal (ULN) in men and women: < 0.5 ULN, 0.5-1 ULN, 1-2 ULN, and ≥ 2 ULN. The hazard ratios for all-cause mortality and cause-specific mortality were analyzed using the Cox proportional hazard model.

RESULTS

Multivariate logistic regression analysis demonstrated that the odds ratio of NAFLD correlated positively with increased serum ALT levels. In patients with NAFLD, all-cause mortality and cardiovascular mortality were the highest when ALT was < 0.5 ULN, yet cancer-related mortality was the highest when ALT was ≥ 2 ULN. The same results could be found in both men and women. Univariate analysis showed that severe NAFLD with normal ALT levels had the highest all-cause and cause-specific mortality, but the difference was not statistically significant after adjustment for age and multivariate factors.

CONCLUSION

The risk of NAFLD was positively correlated with ALT level, but all-cause and cardiovascular mortality were the highest when ALT was < 0.5 ULN. Regardless of the severity of NAFLD, normal or lower ALT levels were associated with higher mortality than elevated ALT levels. Clinicians should be aware that high ALT levels indicate liver injury, but low ALT levels are associated with a higher risk of death.

The Obesity Paradox and Mortality in Older Adults: A Systematic Review

“Obesity paradox” describes the counterintuitive finding that aged overweight and obese people with a particular disease may have better outcomes than their normal weight or underweight counterparts. This systematic review was performed to summarize the publications related to the obesity paradox in older adults, to gain an in-depth understanding of this phenomenon. PubMed©, Embase©, and Scopus© were used to perform literature search for all publications up to 20 March 2022. Studies were included if they reported data from older adults on the relation between BMI and mortality. The following article types were excluded from the study: reviews, editorials, correspondence, and case reports and case series. Publication year, study setting, medical condition, study design, sample size, age, and outcome(s) were extracted. This review has been registered with PROSPERO (no. CRD42021289015). Overall, 2226 studies were identified, of which 58 were included in this systematic review. In all, 20 of the 58 studies included in this review did not find any evidence of an obesity paradox. Of these 20 studies, 16 involved patients with no specific medical condition, 1 involved patients with chronic diseases, and 2 involved patients with type 2 diabetes mellitus. Seven out of the nine studies that looked at short-term mortality found evidence of the obesity paradox. Of the 28 studies that examined longer-term mortality, 15 found evidence of the obesity paradox. In the studies that were conducted in people with a particular medical condition (n = 24), the obesity paradox appeared in 18 cases. Our work supports the existence of an obesity paradox, especially when comorbidities or acute medical problems are present. These findings should help guide strategies for nutritional counselling in older populations.

Assessment of existing anthropometric indices for screening sarcopenic obesity in older adults

Sarcopenic obesity is defined as the presence of high fat mass and low muscle mass combined with low physical function, and it is closely related with the onset of cardiovasular diseases (CVD). The existing anthropometric indices, which are being utilised in clinical practice as predictors of CVD, may also be used to screen sarcopenic obesity, but their feasibility remained unknown. Using cross-sectional data of 2031 participants aged 70-84 years (mean age, 75·9 ± 3·9 years; 49·2 % women) from the Korean Frailty and Aging Cohort Study, we analysed the association of anthropometric indices, including body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR) and weight-adjusted waist index (WWI) with sarcopenic obesity. Body composition was measured using dual-energy X-ray absorptiometry. Higher WWI, WHtR and WC quartiles were associated with higher risk of sarcopenic obesity; the odds ratio (OR) of sarcopenic obesity were highest in the fourth quartile of the WWI (OR: 10·99, 95 % CI: 4·92-24·85, P_{for trend} < 0·001). WWI provided the best diagnostic power for sarcopenic obesity in men (area under the receiver operating characteristic curve: 0·781, 95 % CI: 0·751-0·837). No anthropometric indices were significantly associated with sarcopenic obesity in women. WWI was the only index that was negatively correlated with physical function in both men and women. WWI showed the strongest association with sarcopenic obesity, defined by high fat mass and low muscle mass combined with low physical function only in older men. No anthropometric indices were associated with sarcopenic obesity in older women.

The Association between Plant-Based Diet Indices and Metabolic Syndrome in Chinese Adults: Longitudinal Analyses from the China Health and Nutrition Survey

Objectives: To investigate the association between a plant-based diet and metabolic syndrome (MetS) among Chinese adults. Methods: Based on the data from the 2004–2015 China Health and Nutrition Survey and the corresponding edition of China Food Composition, we calculated the healthy plant-based diet indices (hPDI) and unhealthy plant-based diet indices (uPDI). The Cox proportional hazards regression model was used to estimate the hazard ratios (HRs) with 95% confidence intervals (CIs) for MetS. Mediation analysis was further conducted to explore the mediator role of Body Mass Index (BMI) in the association between hPDI and MetS. Results: We included 10,013 participants, and over a median follow-up of 5 years, 961 patients (9.60%) developed MetS. Compared to those in the lowest quintile of hPDI score, we found that those in the highest quintile of hPDI score had a 28% lower ([HR]: 0.72, 95% CI 0.56–0.93, Ptrend = 0.021) risk of developing MetS and had a 20% lower (hazard ratio [HR]: 0.80, 95% CI 0.70–0.92, Ptrend = 0.004) risk of developing abdominal obesity. No significant associations were observed between uPDI and the MetS, but those in the highest quintile of uPDI score had a 36% higher (hazard ratio [HR]: 1.36, 95% CI 1.20–1.64, Ptrend < 0.001) risk of developing abdominal obesity, compared to those in the lowest quintile of uPDI score. In exploratory analysis, we observed that BMI at baseline mediated 27.8% of the association between hPDI and incident MetS, and BMI at baseline mediated 29.7% of the association between hPDI and abdominal obesity. Conclusion: The current findings reveal a possible causal relationship between a healthy plant-based diet and a reduced risk of MetS, especially abdominal obesity. It is observed that BMI may mediate the relationship between hPDI score and MetS. Controlling early dietary patterns and BMI may help reduce the risk of MetS.

Twelve-Year Trajectory of Disease Burden and Mortality by Obesity Level in Korea: Analysis of the National Health Insurance Service Database

INTRODUCTION

Despite increases in obesity prevalence, awareness of obesity as a disease requiring active treatment remains lacking in Korea. We investigated differences in medical problems and expenditures and mortality across obesity categories using 12-year data from the National Health Insurance Service.

MATERIALS AND METHODS

Individuals aged 40-79 years who underwent medical examinations during 2003-2004 (n = 415,201) were divided based on Asian body mass index (kg/m²) criteria: normal weight (18.5 to < 23.0, 36.4%), overweight (23.0 to < 25.0, 28.3%), obesity (25.0 to < 30.0, 32.5%), and severe obesity (≥ 30.0, 2.8%). Medical problems and expenditures were fitted to linear mixed models. Mortality was analyzed via Cox proportional-hazards model.

RESULTS

More severe obesity was associated with a higher rate of medical problems, relative to normal weight: coefficient = 0.31 (95% confidence interval [CI], 0.30-0.32) for overweight, 0.61 (0.60-0.61) for obesity, and 1.07 (1.04-1.09) for severe obesity. A similar association was observed for medical expenditure: coefficient = 8.85 (95%CI, 6.80-10.89) for overweight, 20.04 (18.07-22.01) for obesity, and 48.76 (43.66-53.86) for severe obesity. Relative to overweight participants, those with normal weight and severe obesity exhibited a higher mortality risk (hazard ratio [HR] 1.21 [95%CI, 1.18-1.25] for normal; 1.27 [1.19-1.36] for severe obesity). In age-specific analyses, mortality risk was the highest for participants with severe obesity, aged < 60 years (HR, 1.58 [95%CI, 1.41-1.77]).

CONCLUSION

Disease burden including medical problems and expenditure, and mortality in middle-aged adults, increased proportionally to the degrees of obesity. Health policies and medical systems aimed at reducing the burden of obesity may help reduce the burden of disease on society.

Association between the weight-adjusted-waist index and abdominal aortic calcification in United States adults: Results from the national health and nutrition examination survey 2013–2014

Background

Abdominal aortic calcification (AAC) is recognized as a strong predictor of cardiovascular disease (CVD) events. This study aimed to evaluate the association between weight-adjusted-waist index (WWI) and AAC in United States adults aged ≥ 40 years.

Materials and methods

Data were derived from the 2013–2014 National Health and Nutrition Examination Survey (NHANES). WWI was calculated as waist circumference divided by the square root of weight. AAC scores were quantified by the Kauppila scoring system, and severe AAC was defined as an AAC score ≥ 6. Weighted multivariable regression analysis and subgroup analysis were performed to evaluate the relationship between WWI with AAC scores and severe AAC. The restricted cubic spline model was used for the dose-response analysis.

Results

A total of 2,772 participants were included with the mean WWI of 11.17 ± 0.73 cm/√kg and mean AAC score of 1.48 ± 3.27. The prevalence of severe AAC was 9.64%. WWI was positively associated with higher AAC scores [β = 0.95, 95% confidence interval (CI): 0.65–1.25, P < 0.001] and increased risk of severe AAC [odds ratio (OR) = 1.82; 95% CI: 1.20–2.75; P = 0.005]. A nearly linear relationship between the WWI and the odds of severe AAC was found after adjustment for multiple potential covariates (P for non-linear = 0.625). Subgroup analysis indicated that the association between WWI and AAC was similar in different population settings.

Conclusion

Higher WWI was associated with higher AAC score and increased risk of severe AAC in United States adults. Further studies are needed to confirm this relationship.

Associations between Weight-Adjusted Waist Index and Abdominal Fat and Muscle Mass: Multi-Ethnic Study of Atherosclerosis

BACKGROUND

The weight-adjusted waist index (WWI) reflected body compositional changes with aging. This study was to investigate the association of WWI with abdominal fat and muscle mass in a diverse race/ethnic population.

METHODS

Computed tomography (CT) data from 1,946 participants for abdominal fat and muscle areas from the Multi-Ethnic Study of Atherosclerosis (785 Whites, 252 Asians, 406 African American, and 503 Hispanics) were used. Among them, 595 participants underwent repeated CT. The WWI was calculated as waist circumference (cm) divided by the square root of body weight (kg). The associations of WWI with abdominal fat and muscle measures were examined, and longitudinal changes in abdominal composition measures were compared.

RESULTS

In all race/ethnic groups, WWI was positively correlated with total abdominal fat area (TFA), subcutaneous fat area, and visceral fat area, but negatively correlated with total abdominal muscle area (TMA) and abdominal muscle radiodensity (P<0.001 for all). WWI showed a linear increase with aging regardless of race and there were no significant differences in the WWI distribution between Whites, Asians, and African Americans. In longitudinal analyses, over 38.6 months of follow-up, all abdominal fat measures increased but muscle measures decreased, along with increase in WWI. The more the WWI increased, the more the TFA increased and the more the TMA decreased.

CONCLUSION

WWI showed positive associations with abdominal fat mass and negative associations with abdominal muscle mass, which likely reflects the abdominal compositional changes with aging in a multi-ethnic population.

Modified Body Mass Index at Diagnosis is a Useful Predictor of Mortality in Patients With Antineutrophil Cytoplasmic Antibody-associated Vasculitis

Objective

We investigated whether modified body mass index (mBMI) at diagnosis could predict all-cause mortality during follow-up in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).

Methods

The medical records of 203 AAV patients with BMI ≥18.5 kg/m2 were reviewed. mBMI was calculated using an equation mBMI=BMI (kg/m2)×serum albumin (g/L). All-cause mortality was considered as a poor outcome, and the follow-up duration based on all-cause mortality was defined as the period from AAV diagnosis to death for deceased patients, and the period from AAV diagnosis to the last visit for surviving patients.

Results

The median age was 59.0 years (35.5% were male). The median BMI and mBMI were 22.8 kg/m2 and 813.2 kg · g/m2 · L. Twenty-five patients (12.3%) died. mBMI was well correlated with age, BVAS, FFS, erythrocyte sedimentation rate and C-reactive protein at diagnosis. Deceased patients exhibited significantly lower mBMI at diagnosis compared to surviving patients. AAV patients mBMI ≤570.1 kg · g/m2 · L showed a significantly higher frequency of all-cause mortality (38.5% vs. 8.5%), and furthermore, exhibited a significantly higher risk for all-cause mortality than those with mBMI >570.1 kg · g/m2 · L (RR 6.750). mBMI ≤570.1 kg · g/m2 · L showed a significantly lower cumulative patients' survival rate than those with mBMI >570.1 kg · g/m2 · L. In the multivariable Cox hazards model analysis, either serum albumin or mBMI was significantly associated with all-cause mortality in AAV patients.

Conclusion

In conclusion, mBMI ≤570.1 kg · g/m2 · L at diagnosis may be a useful predictor of all-cause mortality during follow-up additionally to serum albumin in AAV patients.

Cardiorespiratory Fitness and Carotid Intima-Media Thickness in Physically Active Young Adults: CHIEF Atherosclerosis Study

Background: The relationship of cardiorespiratory fitness (CRF) with subclinical atherosclerosis affected by the body adiposity has been observed in children, whereas this relationship remains unclear in young adults. Methods and Results: A total of 1520 military recruits, aged 18−40 years, were included in Taiwan in 2018−2020. All subjects underwent detailed physical and blood laboratory examinations. CRF was evaluated by time for a 3000 m run, and subclinical atherosclerosis was evaluated by intima−media thickness of the bulb of the left common carotid artery (cIMT) utilizing high-resolution ultrasonography. Multivariable linear regression analysis with adjustments for age, sex, cigarette smoking, alcohol intake, systolic and diastolic blood pressure, high- and low-density lipoprotein cholesterols, fasting glucose, waist circumference, serum uric acid and serum triglycerides were utilized to determine the correlation between CRF and cIMT. CRF was independently correlated with cIMT (standardized β: 0.11, p < 0.001). Of the cardiometabolic risk markers, serum triglycerides were the only independent risk marker of cIMT (standardized β: 0.063, p = 0.03). In addition, the association of CRF with cIMT did not differ between those with a body mass index (BMI) ≥ 25 kg/m2 and those with BMI < 25 kg/m2 (standardized β: 0.103 and 0.117; p = 0.01 and 0.005, respectively). Conclusions: In physically active young men and women, there was an inverse association of cIMT with CRF, which was observed in both overweight/mild obesity and normal-weight individuals, highlighting the importance of endurance capacity on reducing risk of early atherosclerosis and implying that the moderation effect of body adiposity might not be present in this population.

Association of the Weight-Adjusted-Waist Index With Risk of All-Cause Mortality: A 10-Year Follow-Up Study

Background

To explore the relationship between weight-adjusted-waist index (WWI) and the risk of all-cause mortality in one urban community-dwelling population in China.

Methods

This is a prospective cohort study with a sample of 1,863 older adults aged 60 years or over in Beijing who completed baseline examinations in 2009-2010 and a 10-year follow-up in 2020. WWI was calculated as waist circumference (cm) divided by the square root of weight (kg). Cox regression analysis was performed to investigate the significance of the association of WWI with all-cause mortality. The area under the receiver operating characteristic (ROC) curves were used to compare the ability of each obesity index to predict mortality.

Results

During a median follow-up of 10.8 years (1.0 to 11.3 years), 339 deaths occurred. After adjusted for covariates, the hazard ratios (HRs) for all-cause mortality progressively increased across the tertile of WWI. Compared with the lowest WWI category (tertile1 <10.68 cm/√kg), with WWI 10.68 to 11.24cm/√kg, and≥11.25 cm/√kg, the HRs (95% confidence intervals (CIs)) for all-cause mortality were 1.58 (1.12-2.22), and 2.66 (1.80-3.92), respectively. In stratified analyses, the relationship between WWI and the risk of all-cause mortality persisted. The area under ROC for WWI was higher for all-cause mortality than BMI, WHtR, and WC.

Conclusion

WWI was associated with a higher risk for all-cause mortality, and the association was more robust with the highest WWI category.

The effect of age, gender, economic state, and urbanization on the temporal trend in sudden cardiac arrest: a nationwide population-based cohort study

Background

Sudden cardiac arrest (SCA) has not been well studied in Asian countries. This study investigated the temporal trends in the incidence and outcomes of SCA and the impact of age, gender, economic state, and urbanization on SCA using a nationwide population-based sample cohort of South Korea.

Methods

In the Korean National Health Insurance Service—Sample Cohort consisting of one million persons from 2003 through 2013, we identified 5,675 (0.56%) patients with SCA using ICD-10 code I46 and I49.0. We evaluated the impact of the age, gender, household income, and urbanization level on the incidence and outcome of SCA.

Results

During the study period, the overall age- and gender-adjusted annual incidence of SCA increased by 46.9% from 30.9 in 2003 to 45.4 in 2013 (per 100,000 person-years, p < 0.001 for trend). The medical cost per 100,000 person-years also greatly increased about four times (p < 0.001 for trend). The overall adjusted survival to hospital discharge rate increased from 8.9% in 2003 to 13.2% in 2013 (adjusted rate ratio per year 1.05; p < 0.001 for trend). Old age and low household incomes of the population was related to increased SCA and poor survival to hospital discharge rate. The proportion of patients with intensive or advanced therapeutic modalities after SCA greatly increased from 1.6% in 2003 to 10.0% in 2013 (p < 0.001 for trend). This increase was consistent regardless of age, gender, economic state, and urbanization level.

Conclusions

Although the incidence of SCA was increased, the outcome was improved for the decade. However, in the elderly and low-income population, the incidence of SCA continued to rise and survival outcome was not improved.

Combined Effect of Famine Exposure and Obesity Parameters on Hypertension in the Midaged and Older Adult: A Population-Based Cross-Sectional Study

OBJECTIVES

Undernutrition early in life may increase the incidence of adverse effects on adult health. The relations between undernutrition and obesity parameters (body mass index (BMI) and WC (waist circle)) and hypertension were often contradictory. Our study is aimed at identifying the combined effects of famine exposure and obesity parameters on hypertension in middle-aged and older Chinese.

DESIGN

A population-based cross-sectional study. Setting. Data were selected from the China Health and Retirement Longitudinal Study Wave2011 (CHARLS Wave2011). Participants. The sample included 12945 individuals aged 45 to 96. Main Outcome Measurements. The study analyzed data from 12945 middle-aged and older Chinese selected from CHARLS Wave2011. Differences between baseline characteristics and famine exposure/BMI levels/WC levels were evaluated using the t-, Chi-square- (χ 2-), and F-test. Then, the difference in the prevalence of hypertension between baseline characteristics was estimated by the t- and χ 2-test. Finally, multivariable-adjusted logistic regression models were used to explore the associations of famine exposure and obesity parameters with odds of prevalence of hypertension.

RESULTS

Among the 12945 participants, 1548 (11.96%) participants had been exposed to the Chinese famine during the fetal group, whereas 5101 (39.41%) participants and 4362 (33.70%) participants had been exposed to the famine during childhood and adolescence/adult group, respectively. Regarding the participants with BMI levels, 3746 (28.94%) were overweight, and 1465 (11.32%) were obese, whereas 5345 (41.29%) of the participants with WC levels were obese, respectively. Furthermore, 1920 (31.17%) had hypertension in males and 2233 (32.91%) in females. In multivariable-adjusted models, famine exposure and obesity parameters were related with prevalence of hypertension independently in total populations ((1) model threec, famine exposure with prevalence of hypertension: the fatal-exposed vs. no-exposed group (OR1.27; 95% CI 1.08, 1.49); childhood-exposed vs. no-exposed group (OR1.64; 95% CI 1.44, 1.87); the adolescence/adult-exposed vs. no-exposed group (OR3.06; 95% CI 2.68, 3.50); P for trend < 0.001; (2) model threee, famine exposure with prevalence of hypertension: the fatal-exposed vs. no-exposed group (OR1.25; 95% CI 1.06, 1.47); childhood-exposed vs. no-exposed group (OR1.52; 95% CI 1.34, 1.73); the adolescence/adult-exposed vs. no-exposed group (OR2.66; 95% CI 2.33, 3.03); P for trend < 0.001; (3) model threeg, BMI levels with prevalence of hypertension: overweight vs. normal (OR1.75; 95% CI 1.60, 1.91); obesity vs. normal (OR2.79; 95% CI 2.48, 3.15); P for trend < 0.001; (4) WC levels with prevalence of hypertension: overweight vs. normal (OR1.42; 95% CI 1.36, 1.48)). When stratified by sex, results in both males and females were mostly similar to those in the total population. In general, interaction analysis in the multivariable-adjusted model, compared with the combination of normal BMI/WC levels and no-exposed famine group, all groups trended towards higher odds of prevalence of hypertension (the greatest increase in odds, adolescence/adult-exposed group with obesity in BMI levels: (OR8.13; 95% CI 6.18, 10.71); adolescence/adult-exposed group with obesity in WC levels: (OR6.36; 95% CI 5.22, 7.75); P for interaction < 0.001). When stratified by sex, the results in both males and females were also similar to those in the total population.

CONCLUSION

Our data support a strongly positive combined effect of famine exposure and obesity parameters on hypertension in middle-aged and elderly Chinese.

Blood Pressure and Cardio-Metabolic Risk Profile in Young Saudi Males in a University Setting

Background and Objectives: The prevalence of cardiovascular diseases (CVDs) poses significant clinical and public health challenges across the world. This study aimed to study the metabolic risk factors and the association with blood pressure alteration. Materials and Methods: This was a cross-sectional study conducted between 2017 and 2018 among 284 male university students in Eastern province, Saudi Arabia. The obesity and cardiovascular measurements were taken using standardized instruments, including blood pressure (BP), mean arterial pressure, body mass index (BMI), body adiposity index (BAI), waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), body fat percentage (BFP), and basal metabolic rate (BMR). Statistical Analysis: Blood pressure was classified according to the United States of America, Sixth Joint National committee (JNC-VI) guidelines. The mean and standard error were calculated for each hypertension group variable. Logistic regression was applied to predict associations. Results: The prevalence of hypertension in the present study was 61.6%., and that of overweight and obesity was 16.5% and 34.9%, respectively. The cut-off values of BMI and WC were 22.23 and 75.24, respectively. Conclusions: The results demonstrated that BMI, WC, WHR, and WHtR significantly predict hypertension and that WC has a greater discrimination capacity than other measures. The findings also emphasize the importance of cardiovascular risk screening for young adults to detect any alterations in blood pressure and thus identify the population that is vulnerable to CVDs at an early stage. The findings highlight the need for health and university policymakers to adopt measures to monitor and control hypertension and obesity at the university level.

Optimal cut-off values for anthropometric measures of obesity in screening for cardiometabolic disorders in adults

Excessive accumulation of body fat (BF) promotes obesity, whilst posing a significant health hazard. There being no agreed, optimal quantifying methods, application of BF variable in clinical practice is not deemed an effective assessment option. The study, involving 4,735 patients (33.6% men), aged 45-64, aimed to identify optimal cut-off values for anthropometric indicators of obesity to evaluate cardiometabolic risk. A minimum P-value approach was applied to calculate the cut-offs for BF%. Threshold values for body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height (WHTR) ratio, facilitating optimal differentiation of cardiometabolic risk, were based on BF%, expressed as a binary classifier. The newly estimated cut-off values for predicting cardiometabolic risk, based on BMI, were lower than the referential obesity thresholds, whereas the threshold values of WC, WHR, and WHTR were higher. Apart from dyslipidemia, the odds of cardiometabolic disorders were higher, when the anthropometric indicators under study exceeded the cut-off points in both sexes. The proposed cut-offs proved instrumental in predicting cardiometabolic risk, whilst highlighting diagnostic and clinical potential of BF%, whereas BMI boasted the highest predictive potential. Cardiometabolic risk also proved significantly higher even in the overweight patients.

Differential effect of obesity on the incidence of retinal vein occlusion with and without diabetes: a Korean nationwide cohort study

We aimed to evaluate the association between obesity and the incidence of retinal vein occlusion (RVO) with and without diabetes mellitus (DM).This is a retrospective cohort study using Korean National Health Insurance System data. The participants were 23,061,531 adults older than 20 years who received a health examination at least once between 2009 and 2012, and all patients were observed for RVO development until 2015. We used a multivariate adjusted Cox regression analysis to evaluate the association between RVO and body mass index (BMI) with and without DM. The analysis were evaluated via a hazard ratio (HR) and 95% confidence interval (CI). The age-, sex-, and multivariable-adjusted HRs for RVO were stratified by BMI. This population-based study revealed evidence that obesity has a different effect on the incidence of RVO in the presence and absence of DM.In people with DM, a lower BMI was associated with an increased risk of RVO, and a higher BMI was associated with a lower risk for RVO. In people without DM, the correlation was reversed: a lower BMI was associated with a lower risk for RVO and vice versa.

Cumulative evidence for the relationship between body mass index and the risk of esophageal cancer: An updated meta-analysis with evidence from 25 observational studies

BACKGROUND AND AIM

A large number of papers reporting the relationships between body mass index (BMI) and esophageal cancer (EC) risk have been published in the past few decades; however, these results are inconsistent. Therefore, we carried out meta-analyses to explore the relationships between BMI and the risk of EC (including esophageal squamous cell carcinoma [ESCC] and esophageal adenocarcinoma [EADC]).

METHODS

We used the Web of Science, PubMed, and Embase to identify all published/online articles before December 30, 2018, which yielded 25 articles eligible for data extraction (including 16,561 cases and 11,954,161 controls), and then pooled the relative risks (RRs) and corresponding 95% confidence intervals (CIs) using random-effects model.

RESULTS

Our study presented that underweight had statistically significant association with the risk of EC (RR = 1.78, 95% CI = 1.48, 2.14, P < 0.001) and ESCC (RR = 1.57, 95% CI = 1.20, 2.06, P = 0.001) when compared with normal weight. Interestingly, both overweight and obesity could increase the risk of EADC (RR = 1.56, 95% CI = 1.42, 1.71, P < 0.001; RR = 2.34, 95% CI = 2.02, 2.70, P < 0.001) while decrease the risk of ESCC (RR = 0.71, 95% CI = 0.60, 0.84, P < 0.001; RR = 0.63, 95% CI = 0.60, 0.84, P = 0.002). Additionally, obesity could increase the risk of EC (RR = 1.51, 95% CI = 1.21, 1.89, P < 0.001).

CONCLUSION

These meta-analyses provide a comprehensive and updated epidemiological evidence to confirm the associations between BMI and EC risk. These findings have public health implications with respect to better control bodyweight and then reduce the occurrence of EC (including ESCC and EADC).

Obesity, smoking habits, and serum phosphate levels predicts mortality after life-style intervention

Background

Life-style interventions, including smoking cessation and weight control are of importance for managing future escalating prevalence of obesity. Smoking habits and obesity have jointly great impact on mortality, however mechanisms behind the effect and variables involved in the obesity paradox is still unknown.

Objectives

This study examines risk factors for all-cause, cardiovascular, and cancer mortality in males and females with high cardiovascular risk, mediated by smoking habits, body mass index (BMI, kg/m²), and serum phosphate (S-P) levels.

Methods

Patients were admitted to the Vindeln Patient Education Center in groups of 30 for a four-week residential comprehensive program (114 hours) focusing on smoking cessation, stress reduction, food preferences and selections, and physical exercise. The follow-up, in years from 1984 to 2014 corresponds to 30 years. This study included 2,504 patients (1,408 females and 1,096 males). Cox regression analysis was used to assess mortality risk associated with smoking habits, low and high BMI, and low and high S-P levels.

Results

High BMI (>34,2 kg/m²), current smoking, type 2 diabetes mellitus (T2DM), high serum calcium (S-Ca), mmol/L and high systolic blood pressure (SBP, mmHg) were associated with all-cause mortality irrespective of sex. Former and current smoking females had a high all-cause mortality (adjusted hazard ratio [HR] 1.581; 95% CI 1.108–2.256, adjusted hazard ratio [HR] 1.935; 95% CI 1.461–2.562, respectively) while current smoking and high BMI increased risk for cardiovascular mortality (adjusted hazard ratio [HR] 3.505; 95% CI 2.140–5.740 and [HR] 1.536; 95% CI 1.058–2.231, respectively). Neither low nor high levels of S-P predicted all-cause, cardiovascular disease (CVD) and cancer mortality in males or females while low levels of S-P predicted all-cause mortality in smokers (adjusted hazard ratio [HR] 1.713; 95% CI 1.211–2.424). In non-smokers, low BMI (<27.6 kg/m²) was protecting and high BMI a risk for all-cause mortality. In males, ischemic heart disease (IHD), and low serum albumin (S-Alb) were associated with all-cause mortality. In females, an interaction between high BMI and smoking (HbmiSM) decreased the cardiovascular mortality (adjusted hazard ratio [HR] 0.410; 95% CI 0.179–0.937, respectively).

Conclusions

High BMI and current smoking were associated with all-cause mortality in both males and females in the present high cardiovascular-risk cohort. In current smokers and non-smokers, T2DM and high S-Ca were associated with an increase in all-cause mortality, while low S-P was associated with all-cause mortality in smokers. Interaction between high BMI and smoking contribute to the obesity paradox by being protective for cardiovascular mortality in females.

Sex-Specific Differences in the Association of Metabolically Healthy Obesity With Hyperuricemia and a Network Perspective in Analyzing Factors Related to Hyperuricemia

BACKGROUND

Although obesity is a well-known risk factor for hyperuricemia, it remains unclear whether obese subjects with metabolically healthy status have a decreased the risk of hyperuricemia and whether sex modifies the association of metabolically healthy obesity (MHO) with hyperuricemia risk. We aimed to investigate the sex-specific association between MHO and other obesity phenotypes and hyperuricemia, and to use Bayesian networks to determine and visualize the interactions among hyperuricemia and its related factors.

METHODS

This study was conducted using data from the China Health and Nutrition Survey 2009. Hyperuricemia was defined as serum uric acid ≥ 420 μmol/L in men and ≥ 360 μmol/L in women according to the guidelines. Body mass index (BMI) was used to define normal weight, overweight, and obese status in subjects, and metabolic health state was defined by the Adult Treatment Panel (ATP)-III and Visceral Adiposity Index (VAI) criteria, respectively. Subjects were categorized into six phenotypes according to their metabolic health and BMI level status.

RESULTS

Of the 7,364 Chinese adult individuals included, the prevalence of hyperuricemia among MHO women was only 8.5% (95% CI 4.8 to 14.3%), but increased to 30.7% among MUO women, whereas the highest prevalence among men was found in the MUOW phenotype (39.4%, 95% CI 35.4 to 43.6%), compared to 15.4% for male subjects with MHO. After adjusting for confounders, the MHO phenotype was significantly associated with an increased risk of hyperuricemia compared with their MHNW counterparts in women (OR: 1.95, 95% CI: 1.02-3.74) whereas a significant association was not found in men (OR: 1.46, 95% CI: 0.8-2.68). A complex network structure was established by BNs and then used to find connections between hyperuricemia and its related factors, as well as their interrelationships. By using BN reasoning, the probability of having hyperuricemia was 0.076 among MHO men, while it reached 0.124 in MHO women.

CONCLUSIONS

In conclusion, our results demonstrated that the MHO phenotype was significantly associated with the risk of hyperuricemia only in women, not in men. This sex-specific differences in the association may suggest a favorable condition of MHO for Chinese men with respect to hyperuricemia risk, meanwhile more attention should be paid to the increased risk of hyperuricemia among MHO women.

Association of Exposure to Diagnostic Low-Dose Ionizing Radiation With Risk of Cancer Among Youths in South Korea

IMPORTANCE

Diagnostic low-dose ionizing radiation has great medical benefits; however, its increasing use has raised concerns about possible cancer risks.

OBJECTIVE

To examine the risk of cancer after diagnostic low-dose radiation exposure.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study included youths aged 0 to 19 years at baseline from South Korean National Health Insurance System claim records from January 1, 2006, to December 31, 2015. Exposure to diagnostic low-dose ionizing radiation was classified as any that occurred on or after the entry date, when the participant was aged 0 to 19 years, on or before the exit date, and at least 2 years before any cancer diagnosis. Cancer diagnoses were based on International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes. Data were analyzed from March 2018 to September 2018.

MAIN OUTCOMES AND MEASURES

The primary analysis assessed the incidence rate ratios (IRRs) for exposed vs nonexposed individuals using the number of person-years as an offset.

RESULTS

The cohort included a total of 12 068 821 individuals (6 339 782 [52.5%] boys). There were 2 309 841 individuals (19.1%) aged 0 to 4 years, 2 951 679 individuals (24.5%) aged 5 to 9 years, 3 489 709 individuals (28.9%) aged 10 to 14 years, and 3 317 593 individuals (27.5%) aged 15 to 19 years. Of these, 1 275 829 individuals (10.6%) were exposed to diagnostic low-dose ionizing radiation between 2006 and 2015, and 10 792 992 individuals (89.4%) were not exposed. By December 31, 2015, 21 912 cancers were recorded. Among individuals who had been exposed, 1444 individuals (0.1%) received a cancer diagnosis. The overall cancer incidence was greater among exposed individuals than among nonexposed individuals after adjusting for age and sex (IRR, 1.64 [95% CI, 1.56-1.73]; P < .001). Among individuals who had undergone computed tomography scans in particular, the overall cancer incidence was greater among exposed individuals than among nonexposed individuals after adjusting for age and sex (IRR, 1.54 [95% CI, 1.45-1.63]; P < .001). The incidence of cancer increased significantly for many types of lymphoid, hematopoietic, and solid cancers after exposure to diagnostic low-dose ionizing radiation. Among lymphoid and hematopoietic cancers, incidence of cancer increased the most for other myeloid leukemias (IRR, 2.14 [95% CI, 1.86-2.46]) and myelodysplasia (IRR, 2.48 [95% CI, 1.77-3.47]). Among solid cancers, incidence of cancer increased the most for breast (IRR, 2.32 [95% CI, 1.35-3.99]) and thyroid (IRR, 2.19 [95% CI, 1.97-2.20]) cancers.

CONCLUSIONS AND RELEVANCE

This study found an association of increased incidence of cancer with exposure to diagnostic low-dose ionizing radiation in a large cohort. Given this risk, diagnostic low-dose ionizing radiation should be limited to situations in which there is a definite clinical indication.

The effects of blood pressure components on cardiovascular events in a Korean hypertensive population according to age and sex: A nationwide population-based cohort study

There is no known study regarding the usefulness of each blood pressure (BP) component based on stratification by age and sex for predicting cardiovascular (CV) events among hypertensive populations without chronic kidney disease (CKD) or diabetes mellitus (DM). This study was performed to investigate the association of BP components and CV events in a Korean hypertensive population according to age and sex. A total of 22,853 Korean hypertensive participants without CKD and DM were stratified into six groups according to age [40-49, 50-59, and 60 years or older] and sex. In each group, multivariate Cox proportional regression analysis was performed to reveal the associations of BP components [systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP) and pulse pressure (PP)] with CV events. The increase in PP and decrease in DBP were significantly associated with increase of CV events in males, but neither BP component was significantly associated with risk of CV events in females. When subjects were stratified by age and sex, an increase of SBP or PP was significantly related to the increased risk of CV events in 40's male group, and only the elevation of PP was significantly associated with increase in incidence of CV events in 50's male group, while a decrease in DBP was significantly associated with increased risk of CV events in older male group. In addition, there were no the significant associations with the incidence of CV events in MAP, after stratification according to age and sex. In conclusion, this study suggests that, in hypertensive populations, BP management may need to be performed after full consideration of age and sex.

Genetic background, epigenetic factors and dietary interventions which influence human longevity

Longevity is mainly conditioned by genetic, epigenetic and environmental factors. Different genetic modifications seem to be positively associated to longevity, including SNPs in SIRT1, APOE, FOXO3A, ACE, ATM, NOS1 and NOS2 gene. Epigenetic changes as DNA hyper- and hypo-methylation influence significantly human longevity by activating/deactivating different genes involved in physiological mechanisms. Several studies have confirmed that centenarians have a lower DNA methylation content compared to young subjects, which showed more homogeneously methylated DNA region. Also the up-regulation of miR-21 seems to be more associated with longevity in different populations of long-lived subjects, suggesting its role as potential epigenetic biomarkers. A non-pharmacological treatment that seems to contrast age-related diseases and promote longevity is represented by dietary intervention. It has been evaluated the effects of dietary restriction of both single nutrients or total calories to extend lifespan. However, in daily practice it is very difficult to guarantee adherence/compliance of the subjects to dietary restriction and at the same time avoid dangerous nutritional deficiencies. As consequence, the attention has focused on a variety of substances both drugs and natural compounds able to mime the beneficial effects of caloric restriction, including resveratrol, quercetin, rapamycin, metformin and 2-deoxy-D-glucose.

Effect of late-life weight change on dementia incidence: a 10-year cohort study using claim data in Korea

BACKGROUND

The association between body mass index (BMI) in late-life and dementia risk remains unclear. We investigated the association between BMI changes over a 2-year period and dementia in an elderly Korean population.

METHODS

We examined 67 219 participants aged 60-79 years who underwent BMI measurement in 2002/2003 and 2004/2005 as part of the National Health Insurance Service-Health Screening Cohort. Baseline characteristics including BMI, socioeconomic status and cardiometabolic risk factors were measured at baseline (2002/2003). The difference between BMI at baseline and at the next health screening (2004/2005) was used to calculate the BMI change. After 2 years, the incidence of dementia was monitored for a mean 5.3 years from 2008 to 2013. Multivariate HRs for dementia incidence were estimated on the basis of baseline BMI and its changes after adjusting for various other risk factors. A subgroup analysis was conducted to determine the effects of baseline BMI and BMI changes.

RESULTS

We demonstrated a significant association between late-life BMI changes and dementia in both sexes (men: >-10% HR=1.26, 95% CI 1.08 to 1.46, >+10% HR=1.25, 95% CI 1.08 to 1.45; women: >-10% HR=1.15, 95% CI 1.03 to 1.29, >+10% HR=1.17, 95% CI 1.05 to 1.31). However, the baseline BMI was not associated with dementia, except in underweight men. After stratification based on the baseline BMI, the BMI increase over 2 years was associated with dementia in men with a BMI of <25 kg/m² and women with a BMI of 18.5-25 kg/m², but not in the obese subgroup in either sex. However, BMI decrease was associated with dementia in those with a BMI of ≥18.5 kg/m², but not in the underweight subgroup in either sex.

CONCLUSION

Both weight gain and weight loss may be significant risk factors associated with dementia. Continuous weight control and careful monitoring of weight changes are necessary to prevent dementia development.

Waist Circumference and All-Cause Mortality Independent of Body Mass Index in Korean Population from the National Health Insurance Health Checkup 2009⁻2015

BACKGROUND

Waist circumference (WC) is an index of abdominal obesity and associated with co-morbidities and mortality. Higher WC is positively associated with increased mortality; therefore, we examined the relationship between WC and mortality in Korean populations with the interaction of body mass index (BMI) and WC for mortality.

METHODS

A total of 23,263,878 subjects (men = 11,813,850 and women = 11,450,028) who were older than 20 years and underwent the National Health Insurance Service health checkup were included. WC was divided into six categories by 5 cm increments and level 3 (85⁻90 cm in men and 80⁻85 cm in women) was referenced. Multivariable Cox proportional hazard models were used to obtain the hazard ratios (HRs) and 95% confidence intervals for all-cause mortality according to the six levels of WC.

RESULTS

WC in 5 cm increments showed a positively increased all-cause mortality after adjusting for all covariates including BMI. Men showed higher HRs for mortality than women as WC increased, and the HRs were higher in the lower WC levels, but lower in the higher WC levels among the subjects aged 65⁻85 years than subjects aged 40⁻65 years. Even in subjects with normal weight and overweight, increased WC (levels 4, 5, and 6) showed increased HRs for mortality (HRs = 1.156, 1.412, and 1.614 in normal BMI and 1.145, 1.401, and 1.909 in overweight, respectively).

CONCLUSION

There was a linear association between WC and all-cause mortality across all BMI categories even in the subjects with normal or overweight BMI. Physicians should check WC routinely even in the subjects with normal weight or overweight.

Body mass index and mortality in people with and without diabetes: A UK Biobank study

BACKGROUND AND AIMS

To investigate the association of body mass index with all-cause, cardiovascular and cancer mortality in individuals with and without diabetes.

METHODS AND RESULTS

We used data on 490,852 participants from the UK Biobank, with linkage to national mortality data between 2006 and 2016. Using Cox regression, we calculated hazard ratios (HRs) and 95% confidence intervals (95%CI) for all-cause, cardiovascular and cancer mortality within body mass index categories in people with and without diabetes adjusting for potential confounders. 24,789 (5.0%) participants reported having diabetes at baseline. Over a median follow-up of 6.9 years, 13,896 participants died, of which 1800 had diabetes. Compared with normal body mass index (18.5-24.9 kg/m²), mortality risk in the overweight group (25.0-29.9 kg/m²) was 33% lower in people with diabetes (HR 0.67, 95%CI 0.62-0.73) and 12% lower in participants without (HR 0.88, 95%CI 0.85-0.90). For class I obesity (30.0-34.9 kg/m²), mortality risk was 35% lower in participants with diabetes (HR 0.65, 95%CI 0.59-0.71) and 5% lower in participants without (HR 0.95, 95%CI 0.91-0.99). For class III obesity (≥40 kg/m²), there was a 10% non-significant lower mortality risk compared to normal body mass index in people with diabetes (HR 0.90, 95%CI 0.77-1.05); in contrast, the risk was 29% higher in people without diabetes (HR 1.29, 95%CI 1.13-1.45). Similar patterns were observed for cardiovascular mortality but not for cancer mortality.

CONCLUSION

The impact of obesity on the risk of mortality was dependent on the presence of diabetes: for the same level of obesity, mortality risk was higher in people without diabetes compared to those with diabetes.

Association between body mass index and mortality in the Korean elderly: A nationwide cohort study

The objective of this study was to investigate the relationship between body mass index (BMI) and mortality in the elderly. This study was a nation-wide population-based retrospective cohort study of the National Health Insurance System-Senior Database (NHIS-SD). In this study, a total of 75,856 subjects were identified and selected from among 251,593 individuals aged ≥ 65 years who underwent health screening at least once between 2009 and 2012 and who had no history of diabetes, cardiovascular disease, stroke, cancer, or chronic obstructive pulmonary disease (COPD). The subjects of this study were followed-up until 2013 to identify the total mortality and the cause-specific mortality of 6 groups divided according to BMI. The hazard ratio (HR) by reference group (23 ≤ BMI < 25 kg/m²) of each group was calculated. A significant increase in the HR with a decreased BMI was observed in the group with a BMI < 23 kg/m², whereas the HR in the group with a BMI ≥ 25 kg/m² was not significantly different than that of the reference group (23 ≤ BMI < 25 kg/m²). This pattern was also seen in the subgroup analyses in relation to age, smoking history, alcohol use, exercise level, and socioeconomic status. In this study, we found that a low BMI was a risk factor for death in the elderly and that no significant difference in mortality was seen in the elderly with a BMI of 25 or over. In terms of an optimal BMI in the elderly, it is important to maintain an appropriately healthy range of BMI with the aim of preventing weight loss.

A novel adiposity index as an integrated predictor of cardiometabolic disease morbidity and mortality

We propose a new anthropometric index, weight-adjusted-waist index (WWI), to assess adiposity by standardizing waist circumference (WC) for weight. WWI, calculated as WC (cm) divided by the square root of weight (kg) (cm/√kg), was measured from 465,629 subjects in the Korean nationwide cohort (2008-2013). Cox regression analysis was used to compare WWI with BMI, WC, waist-to-height ratio (WHtR), and a body shape index (ABSI) for cardiometabolic morbidity and mortality risk in diagnostic and prognostic prediction models. For incident hypertension, type 2 diabetes and cardiovascular disease (CVD), BMI had the strongest predictive power, followed by WWI and WC. However, WWI showed the best predictive performance for CVD mortality. Also, a linear positive association between adiposity indices and cardiovascular and all-cause mortality was only shown in WWI and ABSI, not BMI, WC and WHtR which showed inverse J-shaped patterns. In the test of joint effects of each index, WWI combined with BMI was the strongest in both diagnostic and prognostic models. WWI is a unique adiposity index that shows linear positive association with both cardiometabolic morbidity and mortality. It also predicts incident cardiometabolic disease, cardiovascular and all-cause mortality risk with excellence in predictive power, especially when combined with BMI.

Serum alanine aminotransferase level and liver-related mortality in patients with chronic hepatitis B: A large national cohort study

BACKGROUND

The serum alanine aminotransferase (ALT) level has been used to identify at-risk patients with chronic hepatitis B (CHB) who need antiviral therapy. However, the level associated with increased liver-related mortality requiring active treatment is still unclear.

METHODS

We used a Health Examination Cohort of the National Health Insurance Service of Korea that included approximately 0.5 million individuals aged 40-79 years. In total, 12 486 patients with CHB and no other concurrent liver disease were enrolled, and patients' liver-related mortality, including that owing to liver cancer, was investigated over 9 years.

RESULTS

The serum ALT level was correlated positively with liver-related mortality. The rates in men were 0.14, 0.17, 0.24, 0.57, 0.63 and 0.85 per 100 person-years (%) for serum ALT levels of <20, 20-29, 30-39, 40-49, 50-79 and ≥80 U/L, respectively, and the corresponding liver-related mortality rates in women were 0.03%, 0.09%, 0.12%, 0.63%, 0.65% and 0.32%. In patients with ALT levels of 40-79 U/L, the liver-related mortality rates were 0.60% in men and 0.64% in women, which were similar to the overall mortality rate of age- and sex-matched subjects without CHB (0.69%). The best cut-off values for liver-related mortality prediction were >34 U/L in men and >30 U/L in women.

CONCLUSIONS

The liver-related mortality rate increased significantly, even in CHB patients with relatively low serum ALT levels. Careful monitoring or earlier antiviral therapy should be considered for patients aged >40 years with serum ALT levels above the upper limit of normal.

Ten-Year Mortality Trends for Adults with and without Diabetes Mellitus in South Korea, 2003 to 2013

BACKGROUND

To estimate and compare the trends of all-cause and cause-specific mortality rates for subjects with and without diabetes in South Korea, from 2003 to 2013.

METHODS

Using a population-based cohort (2003 to 2013), we evaluated annual mortality rates in adults (≥30 years) with and without diabetes. The number of subjects in this analysis ranged from 585,795 in 2003 to 670,020 in 2013.

RESULTS

Age- and sex-adjusted all-cause mortality rates decreased consistently in both groups from 2003 to 2013 (from 14.4 to 9.3/1,000 persons in subjects with diabetes and from 7.9 to 4.4/1,000 persons in those without diabetes). The difference in mortality rates between groups also decreased (6.61 per 1,000 persons in 2003 to 4.98 per 1,000 persons in 2013). The slope associated with the mortality rate exhibited a steeper decrease in subjects with diabetes than those without diabetes (regression coefficients of time: -0.50 and -0.33, respectively; P=0.004). In subjects with diabetes, the mortality rate from cardiovascular disease decreased by 53.5% (from 2.73 to 1.27 per 1,000 persons, P for trend <0.001). Notably, the decrease in mortality from ischemic stroke (79.2%, from 1.20 to 0.25 per 1,000 persowns) was more profound than that from ischemic heart disease (28.3%, from 0.60 to 0.43 per 1,000 persons).

CONCLUSION

All-cause and cardiovascular mortality rates decreased substantially from 2003 to 2013, and the decline in ischemic stroke mortality mainly contributed to the decreased cardiovascular mortality in Korean people with diabetes.

Perspective on Diagnostic Criteria for Obesity and Abdominal Obesity in Korean Adults

Excessive body weight is associated with increased health risks in humans. In general, the risk of mortality increases with greater obesity. The 2018 guideline for the management of obesity by the Korean Society for the Study of Obesity proposed the body mass index (BMI) cut-off levels of 25 kg/m2 and 23 kg/m2 as diagnostic criteria for obesity and overweight (pre-obese) in Korean adults, respectively. Abdominal obesity has been defined as waist circumference (WC) ≥90 cm in men and WC ≥85 cm in women. In this review, the validity of these criteria for Korean adults was examined based on the evidence regarding the associations of obesity index with mortality and morbidity. The American Association of Clinical Endocrinologists/American College of Endocrinology algorithm and American Diabetes Association guideline for the medical care of obese and overweight patients support a BMI of 25 kg/m2 and 23 kg/m2, respectively, as the cut-off levels for Asians (and some ethnicities) corresponding to the BMI values of 30 kg/m2 and 25 kg/m2, respectively, for Caucasians. In the future, the optimal cut-off levels for obesity and abdominal obesity may require adjustment as the demographic characteristics of the Korean population change. In addition, development of more valid indicators that better reflect health risks of obesity is needed.

Anthropometric measurements and mortality in frail older adults

BACKGROUND

As the number of older adults increases, so does the number of frail older adults. Although anthropometry has been widely used as a way to stratify the overall mortality risk of a person, the significance of these measurements becomes blurred in the case of frail older adults who have changes in body composition. Therefore, the aim of this study is to determine the association of anthropometric measurements (body mass index, knee-adjusted height body mass index, waist-to-hip ratio and calf circumference) with mortality risk in a group of older Mexican adults.

METHODS

This is a longitudinal analysis of the Mexican Health and Aging sub-sample (with biomarkers, n = 2573) from the first wave in 2001, followed-up to the last available wave in 2015. Only frail 50-year or older adults (Frailty Index with a cut-off value of 0.21 or higher, was used) were considered for this analysis (n = 1298). A survival analysis was performed with Kaplan-Meier curves and Cox regression models (unadjusted and adjusted for confounding). Socio-demographic, health risks, physical activity and comorbidities were variables used for adjusting the multivariate models.

RESULTS

From the total sample of 1298 older adults, 32.5% (n = 422) died during follow-up. The highest hazard ratio in the adjusted model was for calf circumference 1.31 (95% confidence interval 1.02-1.69, p = 0.034). Other measurements were not significant.

CONCLUSIONS

Anthropometric measurements have different significance in frail older adults, and these differences could have implications on adverse outcomes. Calf circumference has a potential value in predicting negative health outcomes.

Effects of Initial Body Mass Index and Weight Change on All-Cause Mortality: A 10-Year Cohort Study in Korea

We evaluated the effects of baseline body mass index (BMI) and its changes over 4 years on all-cause mortality in Korean population. We analyzed 351 735 participants whose BMI was measured in both 2002/2003 and 2006/2007. Mortality was assessed until 2013. Multivariate hazard ratios for all-cause mortality were estimated. Underweight and severe obesity with BMI >30 kg/m2 were significantly associated with higher mortality. Similarly, >5% decrease or >10% increase of BMI for 4 years was associated with the increased risk of death. Comparing the results between baseline BMI and BMI change, the BMI change showed more stable associations with mortality than the baseline BMI in subgroup analysis such as nonsmokers and healthy participants. This study suggests that BMI change could be a useful health indicator along with obesity level by BMI. In addition, maintaining a healthy weight is needed for longevity, but rapid weight change should be carefully monitored.

Weight Change During the Early Rheumatoid Arthritis Period and Risk of Subsequent Mortality in Women With Rheumatoid Arthritis and Matched Comparators

OBJECTIVE

To investigate whether weight change during the early rheumatoid arthritis (RA) period is associated with subsequent mortality and to evaluate whether there is an RA-specific effect.

METHODS

We identified patients with incident RA during the Nurses' Health Study (NHS; 1976-2016) and created a comparison cohort by matching each RA patient with up to 10 non-RA comparators by age and calendar year of the RA diagnosis (index date). To capture weight change around the early RA period ("peri-RA/index"), we used weight measurements collected 2-4 years before and 2-4 years after the index date. We used Cox regression analysis to estimate hazard ratios (HRs) for mortality according to peri-RA/index weight change categories, separately in each cohort and in the combined cohorts, evaluating for an RA-specific effect.

RESULTS

Among 121,701 women in the NHS, 902 patients with incident RA were identified and matched to 7,884 non-RA comparators. In the RA cohort, 371 deaths (41.1%) occurred during a mean follow-up of 17.0 years after the early RA period, and 2,303 deaths (29.2%) occurred in the comparison cohort during a mean follow-up of 18.4 years. Weight loss of >30 pounds during the peri-RA period had a hazard ratio (HR) for mortality of 2.78 (95% confidence interval [95% CI] 1.58-4.89) compared to stable weight; results in the comparison cohort were similar (HR 2.16, 95% CI 1.61-2.88). A weight gain of >30 pounds had no association with mortality in patients with RA (HR 1.45, 95% CI 0.69-3.07) or comparators (HR 1.19, 95% CI 0.89-1.59). For mortality, there was no statistically significant interaction between RA/comparator status and weight change category (P = 0.68).

CONCLUSION

Severe weight loss during the early RA period was associated with an increased subsequent mortality risk for women with and those without RA. These results extend prior observations by including non-RA comparators and finding no protective association between weight gain and mortality, providing evidence against an RA-specific obesity paradox for mortality.

Associations of changes in body mass index with all-cause and cardiovascular mortality in healthy middle-aged adults

Background

Conflicting data exist regarding the association of body mass index (BMI) changes with all-cause and cardiovascular (CV) mortality. The current study investigated the association between changes in BMI and all-cause, CV, and non-CV mortality in a large cohort of middle-aged adults.

Methods

A total of 379,535 adults over 40 years of age without pre-existing CV disease or cancer at baseline were enrolled to undergo a series of at least three health examinations of biennial intervals. Changes in BMI between baseline, midpoint follow-up, and final health examination during mean 9.3 years were defined according to the pattern of BMI change as follows: stable, sustained gain, sustained loss, and fluctuation. The relationship between BMI change category and mortality was assessed by multivariate Cox regression reporting hazard ratio (HR) with 95% confidence interval (95% CI).

Results

During a mean follow-up of 10.7 years for mortality, 12,378 deaths occurred from all causes, of which 2,114 were CV and 10,264 were non-CV deaths. Sustained BMI gain was associated with the lower risk of all-cause (HR 0.89, 95% CI: 0.83–0.95), CV (HR 0.84, 95% CI 0.72–0.98), and non-CV mortality (HR 0.90, 95% CI 0.84–0.96) compared with stable BMI. Conversely, sustained BMI loss (HR 1.25, 95% CI 1.19–1.32) and fluctuation (HR 1.13, 95% CI 1.08–1.19) displayed a higher risk of all-cause mortality compared with stable BMI, which was mainly attributable to the increase in non-CV mortality.

Conclusion

Sustained BMI gains were associated with reduced risk of all-cause, CV, and non-CV mortality in middle-aged healthy adults.