Body mass index and waist circumference combined predicts obesity-related hypertension better than either alone in a rural Chinese population

Environmental chemical exposures and a machine learning-based model for predicting hypertension in NHANES 2003-2016

BACKGROUND

Hypertension is a common disease, often overlooked in its early stages due to mild symptoms. And persistent elevated blood pressure can lead to adverse outcomes such as coronary heart disease, stroke, and kidney disease. There are many risk factors that lead to hypertension, including various environmental chemicals that humans are exposed to, which are believed to be modifiable risk factors for hypertension.

OBJECTIVE

To investigate the role of environmental chemical exposures in predicting hypertension.

METHODS

A total of 11,039 eligible participants were obtained from NHANES 2003-2016, and multiple imputation was used to process the missing data, resulting in 5 imputed datasets. 8 Machine learning algorithms were applied to the 5 imputed datasets to establish hypertension prediction models, and the average accuracy score, precision score, recall score, and F1 score were calculated. A generalized linear model was also built to predict the systolic and diastolic blood pressure levels.

RESULTS

All 8 algorithms had good predictions for hypertension, with Support Vector Machine (SVM) being the best, with accuracy, precision, recall, F1 scores and area under the curve (AUC) of 0.751, 0.699, 0.717, 0.708 and 0.822, respectively. The R2 of the linear model on the training and test sets was 0.28, 0.25 for systolic and 0.06, 0.05 for diastolic blood pressure.

CONCLUSIONS

In this study, relatively accurate prediction of hypertension was achieved using environmental chemicals with machine learning algorithms, demonstrating the predictive value of environmental chemicals for hypertension.

Correlation between obesity-related indices and hypertension

OBJECTIVES

To explore the correlation between obesity-related indices and hypertension, as well as their predictive ability for hypertension, to provide new insights for the prevention and treatment of the disease.

METHODS

This retrospective study included participants aged over 18 years from Chongqing General Hospital, spanning January 2023 to January 2024. Based on the presence or absence of hypertension, 160 participants were divided into two groups: an observation group (with hypertension, n=83) and a control group (without hypertension, n=77). Demographic and obesity-related indices were collected to assess their correlation with hypertension.

RESULTS

The mean waist circumference (WC) was significantly higher in the observation group 82.46 (78.87-84.35) compared to the control group 82.64 (78.00-84.87), albeit with a typographical error in reporting (P=0.012). The mean A Body Shape Index (ABSI) was significantly higher in the observation group 0.778 (0.078-0.081) compared to the control group 0.076 (0.083-0.087) (P=0.004). The mean body roundness index (BRI) was also significantly higher in the observation group 3.38 (3.07-3.84) than in the control group 3.40 (2.98-3.87) (P=0.02). Logistic regression revealed ABSI (OR=1.15, 95% CI 1.06-1.28, P=0.014), BRI (OR=1.14, 95% CI 1.03-1.23, P=0.048), and WC/BRI (OR=1.13, 95% CI 1.04-1.34, P=0.031) as statistically significant risk factors. The area under the curve values for ABSI, BRI, WC/BRI, and their combination were 0.572, 0.629, 0.652, and 0.731, respectively.

CONCLUSION

ABSI, BRI, and WC/BRI may serve as independent risk factors for hypertension. These indices, individually or combined, could aid in predicting the risk of hypertension.

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.

Revisiting Waist Circumference: A Hypertension Risk Factor that Requires a More In-depth Understanding

As a major cause of various cardiovascular diseases, the prevalence of hypertension has been increasing in the past 30 years, leading to significant socioeconomic and health burdens. Obesity is one of the major risk factors for hypertension. Body mass index (BMI) is the most used anthropometric index to measure obesity in clinical practice and to assess the risk of obesity-related diseases. However, obesity is a heterogeneous disease, and the accumulation of fat in different body regions leads to differences in cardiovascular and metabolic risks. BMI only reflects the overall obesity but does not consider the distribution of fat and muscle mass. The limitation of BMI makes it insufficient to assess the risk of hypertension attributed to obesity. In addition, waist circumference is an easily obtainable anthropometric index to evaluate abdominal fat distribution. High waist circumference is an independent risk factor for various cardiovascular diseases and all-cause mortality regardless of BMI. Preliminary data indicate that waist circumference is significantly associated with the risk of hypertension at different BMI levels. However, routine measurement of waist circumference is currently not required in current clinical guidelines or is only recommended for obese populations, indicating an insufficient understanding of waist circumference. In this review, we summarize the measurement methods and diagnostic thresholds of waist circumference for abdominal obesity, the trend of central obesity prevalence, the superiority of waist circumference over other anthropometric indices, and recent cross-sectional and longitudinal studies on the association between obesity and hypertension.

Life's Essential 8 and Risk of Stroke: A Prospective Community-Based Study

BACKGROUND

Data are lacking regarding cardiovascular health (CVH) with Life's Essential 8 approach and future stroke risk. We sought to elucidate whether the CVH score constructed by the Life's Essential 8 metrics predicted stroke risk in 2 Chinese ongoing cohorts.

METHODS

This included 41 043 participants of the Kailuan I study and 27 842 participants of the Kailuan II study who were free of cardiovascular disease or cancer in 2014. CVH score (ranged from 0 to 100) was assessed using the Life's Essential 8 metrics (body mass index, cigarette smoking, diet quality, physical activity, sleep health, lipid, blood glucose, and blood pressure). A composite of incident stroke events (ischemic stroke and hemorrhagic stroke) was identified via review of medical records. The follow-up period was calculated from the finishing date of the 2014 survey to either the date of stroke occurrence, death, loss to follow-up, or the end of follow-up (December 31, 2020). We also examined the longitudinal association between the CVH score and arterial stiffness status, as assessed by brachial-ankle pulse wave velocity, in 25 922 participants free of cardiovascular disease during the follow-up. We performed a meta-analysis to assess the association between CVH, based on the 2010 American Heart Association recommendation, and stroke integrating the results of current study and previous studies.

RESULTS

During a median follow-up of 5.65 years (interquartile range, 5.20-6.09), a total of 1750 incident stroke events were identified in the pooled Kailuan study. The pooled hazard ratios were 0.33 (95% CI, 0.20-0.54) for ideal versus poor health category of CVH (Ptrend<0.0001). Higher CVH scores were also associated with lower brachial-ankle pulse wave velocity values at baseline and slower increments of brachial-ankle pulse wave velocity during follow-up (Ptrend≤0.001 for both). Arterial stiffness mediated 9.07% (95% CI, 5.83%-15.0%) of the total association between CVH and incident stroke. The pooled hazard ratio comparing 2 extreme CVH categories for stroke was 0.45 (95% CI, 0.35-0.59) when including 10 published studies and the current study.

CONCLUSIONS

The CVH score as assessed by the Life's Essential 8 metrics significantly predicted future stroke risk and arterial stiffness status.

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.

Association of adiposity indices with prehypertension among Chinese adults: A cross-sectional study

The association of adiposity indices with prehypertension remains unclear in the Chinese non-hypertensive population. This study aimed to compare the association of adiposity indices, including waist circumference (WC), waist-to-height ratio, body roundness index (BRI), a body shape index (ABSI), and conicity index (CI), and prehypertension in the Chinese population. We recruited 61 475 participants from a population-based screening project in Guangdong province, China. Multiple logistic regression analyses were performed to detect the association between the six adiposity indices and prehypertension. Receiver operator characteristic curve (ROC) analysis was used to evaluate the predictive values of adiposity indices to prehypertension. The individuals were divided into two categories by blood pressure (BP) levels: normotension (<120/80 mmHg) and prehypertension (120-139/80-89 mmHg). A total of 33 233 people had prehypertension, with a prevalence of 54.04% and 42% males. Both logistics regression models presented a positive association between each adiposity index and prehypertension (p < .05), except for ABSI. The body mass index (BMI) was slightly more correlated with prehypertension than any other index. The standardized ORs for the six indices were 1.392, 1.361, 1.406, 1.039, 1.372, and 1.151, respectively. Compared to other adiposity indices, the WC had a significantly higher area under the curve (AUC) for predicting prehypertension (AUC: .619, sensitivity: 57%, specificity: 60.6%). In conclusion, WC and BMI might be the best indicators for prehypertension. Increasing evidence supports avoiding obesity as a preferred primary prevention strategy for prehypertension while controlling other major hypertension risk factors.

Prevalence and Predictors of Combined Body Mass Index and Waist Circumference Among Indian Adults

Objective: To determine the prevalence and predictors of combined BMI-WC disease risk categories among Indian adults.

Methods: The study utilizes data from Longitudinal Ageing Study in India (LASI Wave 1) with an eligible sample of 66, 859 individuals. Bivariate analysis was done to get the proportion of individuals in different BMI-WC risk categories. Multinomial logistic regression was used to identify the predictors of BMI-WC risk categories.

Results: Poor self-rated health, female sex, urban place of residence, higher educational status, increasing MPCE quintile, and cardio-vascular disease increased with increasing BMI-WC disease risk level while increasing age, tobacco consumption, and engagement in physical activities was negatively associated with BMI-WC disease risk.

Conclusion: Elderly persons in India have a considerable higher prevalence of BMI-WC disease risk categories which make them vulnerable to developing several disease. Findings emphasize the need of using combined BMI categories and waist circumference to assess the prevalence of obesity and associated disease risk. Finally, we recommend that intervention programs with an emphasis on urbanites wealthy women and those with a higher BMI-WC risk categories be implemented.

Multiple Trajectories of Body Mass Index and Waist Circumference and Their Associations with Hypertension and Blood Pressure in Chinese Adults from 1991 to 2018: A Prospective Study

Body mass index (BMI) and waist circumference (WC) have been suggested to be involved in the etiology of hypertension. The present study aimed to determine multiple trajectories of BMI and WC, then examined their associations with the risks of hypertension and high blood pressure in Chinese adults. The study used China Health and Nutrition Survey data from 1991 to 2018. The sample included 9651 adults aged 18 years or older. We used group-based multi-trajectory modeling to identify trajectories. We estimated the relationships between the trajectories and the risks of hypertension with a Cox proportional hazards regression model and the trajectories' relationships with blood pressure levels with a generalized linear model. We identified four trajectories for each gender: low stable BMI, low increasing WC (group 1); medium increasing BMI, medium increasing WC (group 2); increasing BMI to overweight, increasing WC to central obesity (group 3), increasing BMI to obesity, increasing central obesity WC (group 4). Group 1 was the reference group. Among males in groups 2, 3, and 4, the adjusted hazard ratios (HR) and 95% confidence intervals (95% CI) of hypertension were 1.30 (1.15-1.48), 1.86 (1.58-2.18), and 2.60 (2.02-3.34), respectively. The systolic blood pressure (SBP) and diastolic blood pressure (DBP) of males in group 4 increased by 11.90 mm of mercury (mmHg) and 7.75 mmHg, respectively. Among females in groups 2, 3, and 4, the HR and 95% CI of hypertension were 1.35 (1.18-1.54), 1.92 (1.62-2.26), and 2.37 (1.85-3.03), respectively. The SBP and DBP of females in group 4 increased by 8.84 mmHg and 5.79 mmHg, respectively. These data indicated that increases in BMI and WC were associated with unfavorable hypertension risks. Attention to both BMI and WC trajectories has the potential to prevent hypertension.

The value of combining the simple anthropometric obesity parameters, Body Mass Index (BMI) and a Body Shape Index (ABSI), to assess the risk of non-alcoholic fatty liver disease

Background

Body mass index (BMI) and A Body Shape Index (ABSI) are current independent risk factors for non-alcoholic fatty liver disease (NAFLD). The aim of this study was to explore the value of combining these two most common obesity indexes in identifying NAFLD.

Methods

The subjects in this study were 14,251 individuals from the NAfld in the Gifu Area, Longitudinal Analysis (NAGALA) cohort who underwent routine health examination. We integrated BMI with WC and with ABSI to construct 6 combined obesity indicators—obesity phenotypes, the combined anthropometric risk index (ARI) for BMI and ABSI, optimal proportional combination O_BMI+WC and O_BMI+ABSI, and multiplicative combination BMI*WC and BMI*ABSI. Several multivariable logistic regression models were established to evaluate the relationship between BMI, WC, ABSI, and the above six combined indicators and NAFLD; receiver operating characteristic (ROC) curves were drawn to compare the ability of each obesity indicator to identify NAFLD.

Results

A total of 2,507 (17.59%) subjects were diagnosed with NAFLD. BMI, WC, ABSI, and all other combined obesity indicators were significantly and positively associated with NAFLD in the current study, with BMI*WC having the strongest correlation with NAFLD in female subjects (OR per SD increase: 3.13) and BMI*ABSI having the strongest correlation in male subjects (OR per SD increase: 2.97). ROC analysis showed that ARI and O_BMI+ABSI had the best diagnostic performance in both sexes, followed by BMI*WC (area under the curve: female 0.8912; male 0.8270). After further age stratification, it was found that ARI and multiplicative indicators (BMI*WC, BMI*ABSI) and optimal proportional combination indicators (O_BMI+WC, O_BMI+ABSI) significantly improved the NAFLD risk identification ability of the basic anthropometric parameters in middle-aged females and young and middle-aged males.

Conclusion

In the general population, BMI combined with ABSI best identified obesity-related NAFLD risk and was significantly better than BMI or WC, or ABSI. We find that ARI and the multiplicative combined indicators BMI*WC and BMI*ABSI further improved risk prediction and may be proposed for possible use in clinical practice.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-022-01717-8.

Hypertensive patients’ knowledge and practices on lifestyle modification in Extension 6, Middelburg

Background

Hypertension (HTN) is one of the most common chronic diseases affecting the majority of patients worldwide, including in South Africa. The control of HTN and prevention of complications are major challenges for patients and healthcare workers. The proper control of the disease requires a multifactorial approach consisting of medical treatment, as well as lifestyle modification, with the assistance of healthcare workers. Addressing patients’ beliefs, the practice of lifestyle and acceptance of change are some of the ways of aiding control.

Methods

The researchers used a cross-sectional and descriptive survey to establish the knowledge and practices of lifestyle modifications in patients with hypertension. A validated questionnaire was adopted. A total of 250 participants from the Extension 6 Clinic in Middelburg, Mpumalanga, constituted the study population.

Results

Most of the participants had borderline high blood pressure (37.2%) or uncontrolled high blood pressure (46%). The participants’ knowledge of HTN and its complications was not adequate. The study established that increased age and long duration of HTN were associated with high numbers of uncontrolled HTN. Most of the participants (88.8%) had difficulty exercising. Also, most of the participants (90.8%) did not have a place or facility for exercises. Fifty per cent of the participants were unable to maintain a balanced healthy diet which included fruits and vegetables.

Conclusion

The study explored the participants’ knowledge and practice of lifestyle modification. The participants lacked knowledge regarding the definition of HTN and the meaning of controlled HTN. To assist the patients and improve on the identified pitfalls, each consultation session should include some methods of education, and motivation for healthy behaviours and lifestyle modification. This should be extended to all the people visiting the health facilities for them to adopt a healthier diet, greater intake of vegetables and availability of fitness facilities for the community.

Examining sex disparity in the association of waist circumference, waist-hip ratio and BMI with hypertension among older adults in India

Hypertension is a public health issue touted as a “silent killer” worldwide. The present study aimed to explore the sex differential in the association of anthropometric measures including body mass index, waist circumference, and waist-hip ratio with hypertension among older adults in India. The study used data from the Longitudinal Aging Study in India (LASI) conducted during 2017–18. The sample contains 15,098 males and 16,366 females aged 60 years and above. Descriptive statistics (percentages) along with bivariate analysis were presented. Multivariable binary logistic regression analyses were used to examine the associations between the outcome variable (hypertension) and putative risk or protective factors. About 33.9% of males and 38.2% of females aged 60 years and above suffered from hypertension. After adjusting for the socioeconomic, demographic and health-behavioral factors, the odds of hypertension were 1.37 times (CI: 1.27–1.47), significantly higher among older adults who were obese or overweight than those with no overweight/obese condition. Older adults with high-risk waist circumference and waist-hip ratio had 1.16 times (CI: 1.08–1.25) and 1.42 times (CI: 1.32–1.51) higher odds of suffering from hypertension, respectively compared to their counterparts with no high-risk waist circumference or waist-hip ratio. The interaction effects showed that older females with overweight/obesity [OR: 0.84; CI: 0.61–0.74], high-risk waist circumference [OR: 0.89; CI: 0.78–0.99], and high-risk waist-hip ratio [OR: 0.90; CI: 0.83–0.97] had a lower chance of suffering from hypertension than their male counterparts with the similar anthropometric status. The findings suggested a larger magnitude of the association between obesity, high-risk waist circumference, high-risk waist-hip ratio and prevalent hypertension among older males than females. The study also highlights the importance of measuring obesity and central adiposity in older individuals and using such measures as screening tools for timely identification of hypertension.

The association between a combination of healthy lifestyles and the risks of hypertension and dyslipidemia among adults-evidence from the northeast of China

BACKGROUND AND AIMS

There is increasing evidence that lifestyle factors play an important role in the development of hypertension and dyslipidemia. However, existing research usually evaluated these risk factors individually (such as physical activity, smoking, drinking, obesity and so on), rather than joint evaluation. The aim of this study was to quantify the association between a combination of a healthy lifestyle and the risk of hypertension and dyslipidemia.

METHODS AND RESULT

A healthy lifestyle score was created based on 4 factors: never smoking, moderate to high-intensive physical activity, no alcohol drinking, and normal body mass index. We calculated the healthy lifestyle score using the cumulative number of health factors for each individual. Also, a multivariate analysis was used to assess the relationship between healthy lifestyle and hypertension and dyslipidemia. Among 6446 participants, 650 (10.08%) had lowest healthy lifestyle score (0) and 627 (9.72%) had highest healthy lifestyle score (4), respectively. The adjustment model indicated that participants with the highest score (score: 4), which integrated the four lifestyles, had significantly lower ORs for hypertension compared with the lowest score (score: 0) (0.21; (95%CI: 0.10, 0.43 P-trend< 0.001)). In the adjustment models, compared with lowest healthy lifestyle score, the ORs of highest healthy lifestyle score was: 0.17; (95%CI: 0.07, 0.42 P-trend<0.001) for dyslipidemia.

CONCLUSION

Hypertension and dyslipidemia were negatively correlated with healthy lifestyle score. Interventions with healthy lifestyle to reduce hypertension, dyslipidemia and promote population health are warranted.

Trends of central obesity and associations with nutrients intake and daily behaviors among women of childbearing age in China

Background

Obesity among women of childbearing age has becoming an important public health concern. We aimed to describe the trends of central obesity among Chinese women of childbearing age from 2004 to 2011 and to examine its associations with nutrients intake and daily behaviors.

Methods

Longitudinal data were derived from the China Health and Nutrition Survey. Participants consisted of 2481 women aged 15–44 years old. WC (Waist circumference) and WHtR (Waist to height ratio) were adopted as indicators of central obesity. Generalized linear mixed model was performed to analyze the associations of nutrients intake and daily behaviors with central obesity.

Results

From 2004 to 2011, the prevalence of central obesity among Chinese women of childbearing age increased from 21.6 to 30.7% (WC as indice) or from 22.8 to 32.6% (WHtR as indice) (both p < 0.001). Protein intake above the AMDR (Acceptable macronutrient distribution range) (OR = 1.21, 95% CI 1.05–1.39, p < 0.01) and non-participation in LTPA (Leisure time physical activity) (OR = 1.45, 95% CI 1.17–1.80, p < 0.001) were risk factors for high WC, and the latter was also associated with high WHtR (OR = 1.36, 95% CI 1.10–1.67, p < 0.01). For those women who had high WC & high WHtR, the impacts of protein intake and LTPA became stronger, especial LTPA (OR = 1.53, 95% CI 1.21–1.94, p < 0.001). Age-stratified analyses found that non-participation in LTPA was key factor for central obesity in 15–34 age group, while protein intake above the AMDR was pronounced in the 35–44 age group.

Conclusions

Non-participation in LTPA and protein intake above the AMDR were significant contributors of central obesity, which could be intervention targets to deal with the growing trend of central obesity among women of childbearing age.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12905-022-01600-9.

Assessment of Future Hypertension Risk by Sex Using Combined Body Mass Index and Waist-to-Height Ratio

Background: Body mass index (BMI) and the waist-to-height ratio (WHtR) are widely used anthropometric indices of obesity to predict cardiovascular risks. However, the usefulness of combining WHtR and BMI values to predict hypertension risk by sex has not been well elucidated.

Methods and Results: This cohort study enrolled 45,921 participants (mean [±SD] age 53.8±10.5 years; 47.0% men) without hypertension from among those undergoing annual health checkups. Participants were divided into 4 categories based on median BMI and WHtR values, and the 5-year incidence of hypertension was assessed for both sexes using logistic regression analysis. Mean (±SD) BMI and WHtR values were 23.5±3.1 kg/m² and 0.50±0.05, respectively, in men and 22.4±3.3 kg/m² and 0.53±0.06, respectively, in women. Among the women, those with high BMI and low WHtR had an increased risk of hypertension compared with those with low BMI and low WHtR (odds ratio [OR] 1.37, P<0.001); however, the same result was not found in men (OR 1.14, P=0.080). In both sexes, the incidence of hypertension was higher among participants with low BMI and high WHtR than among those with low BMI and low WHtR (men: OR 1.26, P<0.001; women: OR 1.15, P=0.048).

Conclusions: Using WHtR and BMI together provides a better hypertension risk assessment. Among men, those with a high BMI had no increased hypertension risk when WHtR was low.

Association of Obesity and Hypertension: A Cohort Study in China

The prevalence of general and central obesity has increased rapidly in China for decades, while little is known on obesity-normal weight-central obesity (NWCO) in China. In this study, we aim to depict the trend of the three kinds of obesity and to explore their associations with hypertension in a cohort study in China. We used data from eight waves of the China Health and Nutrition Survey (CHNS) in 1993, 1997, 2000, 2004, 2006, 2009, 2011, and 2015 for analysis. The Cochran–Armitage test was used for trend of the three kinds of obesity or hypertension. Mixed logistic regression was used to explore their relationship. In this study, we found the prevalence of general obesity increased from 20.81% in 1993 to 50.57% in 2015 in China, which was from 19.23% to 56.15% for central obesity and from 27.20% to 49.07% for NWCO, respectively. Males had the highest increase among all the subgroups. The RR for hypertension and general obesity was 3.71 (95%CI: 3.26–4.22), 3.62 (95%CI 3.19–4.12) for central obesity, and 1.60 (95%CI 1.23–2.06) for NWCO after adjusted for age, sex, education, smoking, alcohol drinking, marriage status, urbanicity and income. Both prevalence of obesity and hypertension have increased significantly in China for the two decades. The general obesity was most likely to develop hypertension compared to central or NOCWO in this study.

Predicting the Risk of Hypertension Based on Several Easy-to-Collect Risk Factors: A Machine Learning Method

Hypertension is a widespread chronic disease. Risk prediction of hypertension is an intervention that contributes to the early prevention and management of hypertension. The implementation of such intervention requires an effective and easy-to-implement hypertension risk prediction model. This study evaluated and compared the performance of four machine learning algorithms on predicting the risk of hypertension based on easy-to-collect risk factors. A dataset of 29,700 samples collected through a physical examination was used for model training and testing. Firstly, we identified easy-to-collect risk factors of hypertension, through univariate logistic regression analysis. Then, based on the selected features, 10-fold cross-validation was utilized to optimize four models, random forest (RF), CatBoost, MLP neural network and logistic regression (LR), to find the best hyper-parameters on the training set. Finally, the performance of models was evaluated by AUC, accuracy, sensitivity and specificity on the test set. The experimental results showed that the RF model outperformed the other three models, and achieved an AUC of 0.92, an accuracy of 0.82, a sensitivity of 0.83 and a specificity of 0.81. In addition, Body Mass Index (BMI), age, family history and waist circumference (WC) are the four primary risk factors of hypertension. These findings reveal that it is feasible to use machine learning algorithms, especially RF, to predict hypertension risk without clinical or genetic data. The technique can provide a non-invasive and economical way for the prevention and management of hypertension in a large population.

Weight change and mental health according to obesity in relatively healthy middle-aged Korean women: The Korea National Health and Nutrition Examination Survey 2014, 2016, 2018

BACKGROUND

Obesity is a known risk factor for various chronic conditions, as well as mental health disorders. However, there have been few studies on weight change and mental health according to obesity. This study was performed to elucidate the association between weight changes and mental health according to obesity in middle-aged women.

METHODS

Data from the Korean National Health and Nutrition Examination Survey (2014, 2016, 2018), which included 3953 women aged 40 to 59, were used in this study. After excluding those who had chronic conditions possibly affecting weight change, 2964 women were included in the study. The associations between weight changes and mental health, including perceived stress, depressed mood surveyed by the patient health questionnaire-9(PHQ-9), and current depressive disorder were analyzed.

RESULTS

Weight change in non-obese and obese women was associated with poorer mental health, including perceived stress and depressed mood (p<0.05), although the significance disappeared in covariates-adjusted analysis in obese women. Both non-obese and obese women with weight gain had higher perceived stress than women with weight loss, while in the PHQ-9 scores, higher scores were observed in non-obese women with weight gain, and in obese women with weight loss.

LIMITATIONS

Our study could not define causality because this was a cross-sectional study. And the information on body weight change was obtained by self-reported questionnaires.

CONCLUSIONS

Our study suggested that in relatively healthy middle-aged Korean women, weight change was a significant factor associated with mental health, but obesity itself was not.

Abdominal Obesity in Comparison with General Obesity and Risk of Developing Rheumatoid Arthritis in Women

OBJECTIVE

Being overweight or obese increases rheumatoid arthritis (RA) risk among women, particularly among those diagnosed at a younger age. Abdominal obesity may contribute to systemic inflammation more than general obesity; thus, we investigated whether abdominal obesity, compared to general obesity, predicted RA risk in 2 prospective cohorts: the Nurses' Health Study (NHS) and NHS II.

METHODS

We followed 50,682 women (1986-2014) in NHS and 47,597 women (1993-2015) in NHS II, without RA at baseline. Waist circumference (WC), BMI, health outcomes, and covariate data were collected through biennial questionnaires. Incident RA cases and serologic status were identified by chart review. We examined the associations of WC and BMI with RA risk using time-varying Cox proportional hazards models. We repeated analyses restricted to age ≤ 55 years.

RESULTS

During 28 years of follow-up, we identified 844 incident RA cases (527 NHS, 317 NHS II). Women with WC > 88 cm (35 in) had increased RA risk (HR 1.22, 95% CI 1.06-1.41). A similar association was observed for seropositive RA, which was stronger among young and middle-aged women. Further adjustment for BMI attenuated the association to null. In contrast, BMI was associated with RA (HRBMI ≥ 30 vs < 25 1.33, 95% CI 1.05-1.68) and seropositive RA, even after adjusting for WC, and, as in WC analyses, this association was stronger among young and middle-aged women.

CONCLUSION

Abdominal obesity was associated with increased RA risk, particularly for seropositive RA, among young and middle-aged women; however, it did not independently contribute to RA risk beyond general obesity.

Longitudinal association between physical activity and blood pressure, risk of hypertension among Chinese adults: China Health and Nutrition Survey 1991-2015

OBJECTIVES

To examine the effects of physical activity (PA) in adults with or without prehypertension at baseline on systolic blood pressure (SBP), diastolic blood pressure (DBP), and hypertension risk by gender.

METHODS

A total of 5986 men and 6525 women (≥18 years old) without hypertension-related disease at baseline who attended surveys from China Health and Nutrition Survey (1991-2015) at least twice were selected. In terms of the nested data structure, three-level random intercept growth model and three-level logistic regression were used to estimate the relationship between the PA and SBP/DBP or hypertension risk.

RESULTS

The incidence of hypertension increased from 10.86% in 1991 to 20.34% in 2015, and the median of PA dropped from 408 MET·h/week in 1991 to 104 MET·h/week in 2015. After adjusting confounders, PA in the third and fourth quartiles decreased SBP (by 0.98 and 0.96 mm Hg, p < 0.05) and DBP (by 0.30 and 0.38 mm Hg, p < 0.05), and it reduced the odds of hypertension by 12 and 15% (p < 0.05), compared with PA in the lowest quartile. For normotensive women in the third quartile of PA and prehypertensive women in the fourth quartile of PA, the risk of hypertension was reduced 15 and 22%, compared with women in the lowest quartile of PA.

CONCLUSIONS

Physical activity should be improved to the relatively high level to be effective in controlling blood pressure. Normotensive women had an association between physical activity and SBP, DBP, and the risk of hypertension.

A prospective study of waist circumference trajectories and incident cardiovascular disease in China: the Kailuan Cohort Study

Background

Single measurements of waist circumference (WC) predict the incident cardiovascular disease (CVD); however, long-term patterns of WC and their association with the incidence of CVD are poorly characterized.

Objective

We aimed to identify WC trajectories and determine their association with incident CVD (stroke and myocardial infarction) and examine whether the association persisted among individuals without obesity.

Methods

We included 75,535 participants from a community-based cohort in China who were aged &gt;18 y and free of stroke, coronary artery disease, and cancer in 2010 (the baseline). WC and other covariates were repeatedly measured in 2006, 2008, and 2010. WC trajectories were identified by latent mixture modeling. A Cox proportional hazards model was used to examine the association between WC trajectories and incident CVD, after adjustment for age, sex, income, education, systolic blood pressure, lipid profiles, plasma concentrations of glucose, C-reactive protein, smoking, and alcohol drinking.

Results

We identified 4 WC trajectories based on 2006 WC measurement and change patterns during 2006–2010: low stable (n = 12,072; mean WC 74.1–75.1 cm), moderate stable (n = 41,750; mean WC 85.1–86.6 cm), moderate-high stable (n = 19,914; mean WC 95.6–97.2 cm), and high stable (n = 1,799; mean WC 106.3–110.9 cm). During 2010–2016, we documented 2819 incident CVD events. Compared with the low-stable group, groups with elevated WC trajectories had a higher risk of CVD events during 6 y of follow-up (2010–2016). Adjusted HRs (95% CIs) were 1.49 (1.21, 1.83) for the moderate stable group, 1.71(1.38, 2.12) for the moderate-high stable group, and 1.45 (1.06, 2.00) for the high stable group. After further adjusting for BMI or excluding obese participants, we observed similar results. The positive association between WC and incident CVD was higher in individuals who were aged &lt;60 y (P-interaction &lt; 0.0001).

Conclusions

WC trajectory patterns were associated with altered risk of CVD among Chinese adults, even among people without BMI-defined obesity. When stratifying by age, the association was observed to be higher in younger adults.

Association between the 2d:4d and cardiovascular risk factors: Body mass index, blood pressure and body fat

OBJECTIVES

To examine the relationship between the cardiovascular risk factors such as obesity as measured by Body mass index (BMI), body fat and blood pressure with the second to fourth digit ratio (2d:4d); a prenatal testosterone exposure marker.

METHODS

The 2d:4d for both hands were measured for the Indian male subjects' (n = 1217). Subject's anthropometric parameters such as height, weight, skinfold thicknesses at various regions and blood pressure measurements were collected in a cross-sectional study with a convenient sampling approach. The association between digit ratio and the other variables were examined using analysis of variance, Pearson's correlation test and linear regression methods.

RESULTS

The study included 1193 subjects and all were males aged 19.69 ± 5.38 years (range 13 to 40 years). The subjects' body mass index (BMI) was 19.45 ± 3.82 and right and left hand 2d:4d were 0.958 ± 0.054, and 0.958 ± 0.061 respectively. The systolic blood pressure (SBP) and BMI significantly differed between the higher and lower half of right 2d:4d. The left hand 2d:4d was significantly correlated with SBP (r = 0.075, p = 0.028) and significantly differed between different hypertensive groups (p < 0.003, F = 3.552, df = 5).

CONCLUSION

The study observed an association between 2d:4d with hypertension and BMI among young Indian population, emphasizing the effect of prenatal testosterone on late life cardiovascular risk factor.

Usefulness of waist-to-height ratio in screening incident hypertension among Japanese community-dwelling middle-aged and elderly individuals

Background

The incidence of hypertension is increasing worldwide and obesity is one of the most significant risk factors. Obesity can be defined by various anthropometric indices such as body mass index (BMI), waist-to-hip ratio (WHpR), and waist-to-height ratio (WHtR). This study examined a range of anthropometric indices and their relationships with hypertension.

Methods

This study included 768 men aged 70 ± 10 years and 959 women aged 70 ± 8 years from a rural village. The relationship between anthropometric indices (BMI, WHpR, and WHtR) and hypertension was examined using cross-sectional (baseline, N = 1727) and cohort data (follow-up, N = 419). Receiver operating characteristic (ROC) analysis was used to determine the predictive ability of obesity indices for hypertension in both genders. Logistic regression models were used to evaluate WHtR as a significant predictor of hypertension.

Results

In the cross-sectional study, WHtR, BMI, and WHpR showed significant predictive abilities for hypertension in both genders, with WHtR showing the strongest predictive ability. Also, in the cohort study, WHtR showed a significant predictive ability for incident hypertension in both genders, and, for women, BMI as well as WHtR had also predictive ability. In the cross-sectional study, the optimal WHtR cutoff values were 0.53 (sensitivity, 44.3%; specificity, 80.2%) for men and 0.54 (sensitivity, 60.9%; specificity, 68.6%) for women. In the cohort study, the optimal WHtR values were 0.47 (sensitivity, 85.4%; specificity, 39.8%) for men and 0.51 (sensitivity, 66.7%; specificity, 58.2%) for women.

Conclusions

The results suggest that WHtR is a useful screening tool for hypertension among Japanese middle-aged and elderly community-dwelling individuals.

Obesity-related hypertension: Findings from The Korea National Health and Nutrition Examination Survey 2008-2010

We aimed to investigate the association of various obesity parameters and phenotypes with hypertension in nationally representative Korean adults. Among adults aged 19 years and older who participated in the Korea National Health and Nutrition Examination Survey in 2008-2010, a total of 16,363 subjects (8,184 men and 8,179 women) were analyzed. Hypertension was defined as blood pressure of 140/90 mm Hg or higher or taking antihypertensive medication. Multiple logistic regression analysis was used to estimate multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (CIs). Higher obesity parameters [body mass index (BMI) representing general obesity, waist circumference (WC) representing central obesity, and percentage body fat (PBF) representing elevated body fat] were consistently associated with increased odds of prevalent hypertension (OR, 7.54; 95% CI, 5.89-9.65 for BMI ≥30 vs. 18.5-23; OR, 3.97; 95% CI, 3.41-4.63 for WC ≥95 cm in males and ≥90 cm in females vs. <85 cm in males and <80 cm in females; OR, 3.56; 95% CI, 3.05-4.15 for PBF, highest vs. lowest quartile; all p trends<0.0001). These associations were stronger in the younger age group (<40 years), and were observed in both sexes. Furthermore, even in individuals with normal BMI (18.5-23), the odds of prevalent hypertension were consistently increased in those with central obesity (WC≥90 cm in males, WC≥80 cm in females; normal weight central obesity phenotype) (OR, 1.89; 95% CI, 1.63-2.19) and those with high PBF (highest quartile of PBF; normal weight obesity phenotype) (OR, 1.49; 95% CI, 1.25-1.77). These associations were consistent with updated hypertension guidelines in 2017. Obesity may be positively associated with hypertension, regardless of obesity parameters. Even within normal BMI range, high WC and high PBF may be associated with hypertension.

Associations between adiposity indicators and hypertension among children and adolescents with intellectual disability-A case-control study

BACKGROUND

Adiposity is closely related to hypertension (HTN) in paediatric population. However, which adiposity indicator is most associated with HTN among children and adolescents with intellectual disability remains unknown. The aim of this study was to evaluate the associations between HTN prevalence and different adiposity indicators: body mass index (BMI) percentile, body fat percentage (BFP), waist circumference (WC), hip circumference (HC), waist-hip ratio (WHR) and waist-to-height ratio (WHtR) in students with intellectual disability.

METHODS

Cross-sectional study included a sample of 568 schoolchildren with intellectual disability, aged 7-18 years. Blood pressure, BMI, body composition, WC and HC were determined using standardized equipment.

RESULTS

Multivariate logistic regression showed that male gender, adolescence, high HC and excessive BFP were significant independent factors that increased risk of HTN occurrence in population with intellectual disability.

CONCLUSIONS

Findings indicated that HC and BFP, in particular, may be helpful tools to detect HTN in population with intellectual disability.

Effects of Physical Exercises and Verbal Stimulation on the Functional Efficiency and Use of Free Time in an Older Population under Institutional Care: A Randomized Controlled Trial

Older people in institutional care are, for the most part, physically inactive and do not interact with each other or medical staff. Therefore, reducing sedentary behaviour is a new, important, and modifiable lifestyle variable that can improve the health of elderly people. The aim of the project was to assess the degree of improvement in functional performance and the possibility of changing habitual, free time behaviour among elderly people under institutional care by applying physical training with verbal stimulation. The study covered older people, aged 65–85 years, who are living a sedentary lifestyle in care homes in Southeastern Poland. Those who met the eligibility criteria were enrolled in the study and were assigned, at random, to one of four parallel groups: basic exercises (n = 51), basic exercises combined with verbal stimulation (n = 51), functional exercise training (n = 51), and functional exercise training with verbal stimulation (n = 51). No statistically significant differences in baseline characteristics were observed across the groups. Data were collected at baseline and at 12 and 24-weeks following the completion of the intervention. In the group with functional exercise training with verbal stimulation, in comparison to the group with basic exercises, the greatest positive short-term impact of intervention was demonstrated in terms of functional fitness (increased by 1.31 points; 95% confidence interval (CI) = 0.93–1.70), gait speed (improved by 0.17 m/s, 95% CI = 0.13–0.22), hand grip strength (by over 4 kg; 95% CI = 2.51–4.95), and upper-limb flexibility (by 10 cm; 95% CI = 5.82–12.65). There was also a significant increase in the level of free-time physical activity and an improvement in the quality of life, especially as expressed in the domain of overall physical functioning. Our study showed that a functional exercise program, combined with verbal stimulation, is effective at improving physical fitness and raising the level of free-time physical activity.

Obesity-related hypertension: a review of pathophysiology, management, and the role of metabolic surgery

Obesity is a significant public health challenge worldwide and is inextricably linked to adverse cardiovascular outcomes. The relationship between excess adiposity and increased blood pressure is well established, and it is estimated that obesity accounts for 65-78% of cases of primary hypertension. The mechanisms through which obesity causes hypertension are complex and include sympathetic nervous system overactivation, stimulation of the renin-angiotensin-aldosterone system, alterations in adipose-derived cytokines, insulin resistance, and structural and functional renal changes. Weight loss is the primary goal of treatment for obesity-related hypertension, although few individuals achieve success with nonpharmacological management alone. Specific considerations apply when selecting the most appropriate pharmacological therapy for obese hypertensive patients. Metabolic surgery has proved to be the most effective means of ensuring substantial and sustained weight loss and has also been shown to confer beneficial effects in type 2 diabetes mellitus. Increasing evidence suggests that metabolic surgery may also be an effective treatment for obesity-related hypertension, although prospective data on long-term blood pressure outcomes are awaited. This review will discuss the pathophysiological mechanisms that link obesity with hypertension and will provide an overview of treatment strategies, with a focus on metabolic surgery.

Joint Effects of Body Mass Index and Waist Circumference on the Incidence of Hypertension in a Community-Based Chinese Population

OBJECTIVE

We aimed to investigate the relationships of body mass index (BMI), waist circumference (WC), and obesity defined using a combination of both indexes, with the incidence of hypertension in a Chinese community-based population.

METHODS

A total of 1,927 Chinese participants (57.2 ± 8.9 years old) with normal blood pressure at baseline were recruited from the Shijingshan community in Beijing. Incident hypertension was defined as blood pressure ≥140/90 mm Hg, self-reported hypertension, or the use of any antihypertensive medication at the follow-up visit.

RESULTS

During 2.3 years of follow-up, 19.1% (n = 97) of the men and 13.6% (n = 158) of the women developed incident hypertension. The adjusted odds ratios (ORs) (95% confidence intervals [CIs]) for obesity (BMI ≥30) were 3.49 (1.59-7.66) and 2.60 (1.48-4.55) for men and women, respectively. A 1-point increase in BMI was associated with 8% (OR = 1.08, 95% CI: 1.00-1.17) and 10% (OR = 1.10, 95% CI: 1.05-1.16) increases in the incidence of hypertension in men and women, respectively. Abdominal obesity (WC ≥90 cm in men and ≥85 cm in women) was positively associated with incident hypertension in both men (adjusted OR = 1.79, 95% CI: 1.10-2.91) and women (adjusted OR = 1.61, 95% CI: 1.09-2.40). A 1-cm increase in WC was associated with 4% (adjusted OR = 1.04, 95% CI: 1.01-1.07) and 4% (adjusted OR = 1.04, 95% CI: 1.02-1.07) increases in the incidence of hypertension in men and women, respectively. The combination of abnormal BMI and WC has the highest risk for hypertension in both men (adjusted OR = 3.10, 95% CI: 1.48-6.50) and women (adjusted OR = 2.51, 95% CI: 1.43-4.40).

CONCLUSIONS

This study shows that BMI, WC, and an index that combined the two are independently associated with incident hypertension in a Chinese community-based population.

The ability of waist-to-height ratio to identify health risk

OBJECTIVE

To evaluate the performance of the ratio between the waist circumference and the height in the identification of health risk compared with the correlation matrix between the anthropometric parameters body mass index and waist circumference.

METHODS

A population-based study presenting a transversal cut in a representative sample of the Brazilian adult and older population. The combination of the body mass index with the waist circumference resulted in health risk categories, and the cutoff points of the ratio between the waist circumference and the height as anthropometric indicator were used for classification of low and increased risk. Poisson regression was used to verify the association of systemic arterial hypertension with the health risk categories.

RESULTS

The results showed 26% of adult men, 10.4% of adult women and more than 30% of the older adults of both genders classified as without risk by the combination matrix between body mass index and waist circumference presented a ratio between the waist circumference and height that showed increased risk. All risk categories continued to be associated with hypertension after control for confounding factors, being almost two times higher for adults with moderate and high risk according to both methods. When the waist-to-height ratio was used as a risk indicator, the prevalence of hypertension ratios for the older adults was 1.37 (95%CI 1.16–1.63) and 1.35 (95%CI 1.12–1.62) for men and women, respectively, being these values close to the combination matrix body mass index and waist circumference.

CONCLUSIONS

The waist-to-height ratio identified more individuals at early health risk than the combination matrix between the body mass index and the waist circumference and showed comparable ability to identify health risk, regardless of gender and age, regarding the prevalence ratios for systemic arterial hypertension.

The effect of exercise training on blood pressure in African and Asian populations: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Exercise is key in the primary prevention and management of hypertension. Yet, current exercise recommendations are predominantly based on meta-analyses involving populations of European descent. Since blood pressure (BP) responses to pharmaceutical interventions are known to differ among ethnic groups, we aimed to investigate the BP responses to exercise training in non-European descendants.

PURPOSE

The aim of this study was to systematically summarize the available literature on the efficacy of exercise on BP in healthy adults (age ≥18 years) of African or Asian origin.

METHODS

We searched the MEDLINE database for randomized controlled trials that evaluated the effect of exercise training on BP in healthy African and Asian adults with optimal BP, elevated BP or hypertension and published in a peer-reviewed journal up to May 2019. Random effect models were fitted to estimate the effect sizes.

RESULTS

We identified 22 trials involving individuals of Asian origin (n = 931; mean age: 44 years; 41% male) and four trials involving individuals of African origin (n = 510; mean age: 56.7 years; 80% male). Aerobic exercise training significantly (p < 0.001) reduced systolic and diastolic BP in each ethnic group. Resistance training did not affect the BP of Asian participants with optimal BP. The effect of resistance training in Asians with elevated BP or hypertension and Africans could not be determined due to lack of data. Sub-analyses suggested somewhat larger reductions in systolic BP following aerobic training in hypertensive Africans compared with hypertensive Asians.

CONCLUSIONS

We found favorable effects of aerobic exercise training on BP in the African and the Asian populations. However, the overall low number of studies and especially the lack of data on resistance training and combined training in African and Asian populations warrant more research to improve the quality of evidence.

Changes in distributions of waist circumference, waist-to-hip ratio and waist-to-height ratio over an 18-year period among Chinese adults: a longitudinal study using quantile regression

BACKGROUND

Little is known about the long-term shifts in distributions of three abdominal-obesity-related indicators, waist circumference (WC), waist-to-hip ratio (WHpR) and waist-to-height ratio (WHtR) among Chinese adults. Traditional mean regression models used in the previous analyses were limited in their ability to capture cross-distribution among effects. The current study aims to describe the shift in distribution of WC, WHpR, and WHtR over a period of 18 years (1993-2011) in China, and to reveal quantile-specific associations of the three indicators with key covariates.

METHODS

Longitudinal data from seven waves of the China Health and Nutrition Surveys (CHNS) in 1993, 1997, 2000, 2004, 2006, 2009 and 2011 were analyzed. The LMS method was used to illustrate the gender-specific quantile curves of WC, WHtR and WHpR over age. Separate gender-stratified longitudinal quantile regressions were employed to investigate the effect of important factors on the trends of the three indicators.

RESULTS

A total of 11,923 participants aged 18-65 years with 49,507 observations were included in the analysis. The density curves of WC, WHtR and WHpR shifted to right and became wider. The three outcomes all increased with age and increased more at upper percentiles. From the multivariate quantile regression, physical activity was negatively associated in both genders; smoking only had a negative effect on male indicators. Education and drinking behavior both had opposite effects on the three indicators between men and women. Marital status and income were positively associated with the shifts in WC, WHtR and WHpR in male and female WC, while urbanicity index had a positive effect on three outcomes in men but inconsistent effect among female outcomes.

CONCLUSIONS

The abdominal-obesity related indicators of the Chinese adults experienced rapid growth according to our population-based, age- and gender-specific analyses. Over the 18-year study period, major increases in WC, WHtR and WHpR were observed among Chinese adults. Specifically, these increases were greater at upper percentiles and in men. Age, physical activity, energy intake, drinking, smoking, education, income and urbanicity index were associated with elevated abdominal obesity indicators, and the effects differed among percentiles and between genders.

Adjustment for Waist Circumference Reveals a U-Shaped Association Between Glycated Hemoglobin Levels and Body Mass Index in Young Adults

OBJECTIVES

Body mass index (BMI) is used to assess adiposity worldwide. However, additional adjustment for waist circumference (WC), a surrogate marker of abdominal fat, may be capable of revealing a latent relationship between low body weight and glycated hemoglobin (A1C) concentration. Here, we investigated the relationship between A1C and BMI in young adults, adjusting for WC.

METHODS

We reviewed A1C, BMI, WC and other clinical data in a cross-sectional study of 26,475 apparently healthy Japanese people 20 to 39 years of age who were undergoing health check-ups.

RESULTS

Although the values of most serum parameters were high in subjects with a high BMI in both younger (20 to 29 years of age, n=10,810) and older subjects (30 to 39 years of age, n=15,665), A1C had a J-shaped relationship with BMI category in younger subjects, regardless of sex. A traditional linear model via a generalized linear model showed that in younger subjects, an inverse association of A1C level with BMI category (19 to 26.9 kg/m² vs. ≤18.9 kg/m²) was identified after adjustment for WC. This indicates positive associations between A1C and BMI categories of ≤18.9 (beta=0.06; p<0.0001), 19.0 to 20.9 (beta=0.03; p<0.01) and ≥27.0 kg/m² (beta=0.08; p<0.0001), in contrast to individuals with BMIs of 23.0 to 24.9 kg/m². Similarly, in older subjects, BMIs ≤18.9 kg/m² were associated with A1C levels but to a lesser extent (beta=0.04; p<0.05) than in younger subjects.

CONCLUSIONS

Additional adjustment of BMI for WC revealed a latent U-shaped association between A1C concentration and BMI, particularly in young adults; this deserves further investigation.

C-reactive protein and incident hypertension in a worksite population of Japanese men

Inflammation plays a key role in the pathogenesis of cardiovascular diseases via the development of atherosclerosis. Here, we evaluated the impact of serum C-reactive protein (CRP) and the white blood cell (WBC) count on the risk of hypertension in middle-aged Japanese men at a work site. We evaluated a total of 2991 Japanese male workers without hypertension who ranged in age from 18 to 64 years (mean age 40.4 ± 0.2 years) at a worksite in 2010. The hazard ratio (HR) for incident hypertension was estimated according to quartile levels of serum high-sensitivity CRP (hs-CRP) or WBC count. These men were followed up for 5 years from 2010 to 2015. During the follow-up period, 579 (19.4%) subjects developed hypertension. In a multivariable analysis, the risk of incident hypertension was significantly increased with higher hs-CRP levels: HR 1.00 (reference) for the lowest quartile, 1.39 (1.04-1.85) for the 2nd quartile, 1.46 (1.08-1.98) for the 3rd quartile, and 1.57 (1.17-2.11) for the highest quartile. In contrast, the WBC count was not associated with a greater risk of incident hypertension after multivariable adjustment. These findings suggest that higher levels of serum hs-CRP, but not the WBC count, are associated with the future incidence of hypertension in middle-aged Japanese men.

Body mass index and risk of all-cause mortality with normoglycemia, impaired fasting glucose and prevalent diabetes: results from the Rural Chinese Cohort Study

BACKGROUND

Previous evidence of an association between body mass index (BMI) and mortality in patients with diabetes was inconsistent. The BMI-mortality association with normal fasting glucose (NFG), impaired fasting glucose (IFG) and prevalent diabetes is still unclear in the Chinese population.

METHODS

We analysed data for 17 252 adults from the Rural Chinese Cohort Study during 2007-2008 and followed for mortality during 2013-2014. Participants were classified with NFG, IFG and diabetes according to baseline measurement values of fasting glucose and self-reported diabetes. Multivariable Cox proportional hazard models were used to calculate HRs and 95% CIs across BMI categories by glycemic status.

RESULTS

During the 6-year follow-up, 1109 participants died (563/10 181 with NFG, 349/5572 with IFG and 197/1499 with diabetes). The BMI-mortality association was curvilinear, with low BMI (even in normal range) associated with increased mortality regardless of glycemic status. In adjusted Cox models, risk of mortality showed a decreasing trend with BMI≤18 kg/m², 18<BMI≤20 kg/m² and 20<BMI≤22 kg/m² vs 22<BMI≤24 kg/m²: HR 2.83 (95% CI 1.78 to 4.51), 2.05 (1.46 to 2.87) and 1.45 (1.10 to 1.90), respectively, for NFG; 2.53 (1.25 to 5.14), 1.36 (0.86 to 2.14) and 1.09 (0.76 to 1.57), respectively, for IFG; and 4.03 (1.42 to 11.50), 2.00 (1.05 to 3.80) and 1.52 (0.88 to 2.60), respectively, for diabetes. The risk of mortality was lower for patients with diabetes who were overweight or obese versus normal weight.

CONCLUSIONS

Low BMI was associated with increased mortality regardless of glycemic status. Future studies are needed to explain the 'obesity paradox' in patients with diabetes.

Impact of a motivational resistance-training programme on adherence and body composition in the elderly

Lack of physical activity is one of the major causes for obesity and functional disability in the elderly. Including regular exercise in the elderly's lifestyle is not an easy task. The main objective was to analyse the effect of a motivational resistance-training programme on satisfying the individual's psychological needs, level of self-determination and body composition. A quasi-experimental study was performed with 47 volunteers (29 females, 18 males) of 67-75 years of age, divided into two groups: experimental (n = 27) and control (n = 20). A 12-week intervention programme was performed, with a total of 36 sessions. The results of the inter-group analysis indicated significant differences in the post-test measurement between the experimental group and the control group (in favour of the experimental group) regarding basic psychological needs. The experimental group, in comparison to the control group, significantly decreased their percentage of fat mass and increased muscle mass. Body weight and BMI values increased in the control group, while significantly decreasing in the experimental group. In conclusion, the motivational resistance-training programme in the elderly gave rise to positive significant changes at the physical, psychological and social levels, according to the definition of health by the World Health Organization.