Prospective study of body size and risk for stroke amongst women below age 60

The effect of regular running on body weight and fat tissue of individuals aged 18 to 65

BACKGROUND

Age and reduction in performed physical activity cause physiological changes that include an increase in body fat (BF) and visceral fat (VF) during aging. These parameters, together with increased body mass (BM), are some of the risk factors of several noninfectious diseases. However, changes in body composition can be influenced by regular physical activity. Running is a suitable, accessible, and the most effective physical activity cultivating people. The objective of this study is to investigate the effects of long-term, regular PA, specifically recreational running, on changes in body composition among recreational adult runners covering a weekly distance of at least 10 km, compared with inactive adult individuals within the same age bracket.

METHODS

The study included 1296 runners and inactive individuals (691 male and 605 female), divided into 5 age groups: 18-25, 26-35, 36-45, 46-55, and 56-65 years. Runners are as follows: ran ≥ 10 km/week, and inactive is as follows: did not follow the WHO 2020 physical activity recommendations. The measured parameters included BM, BF, and VF. To check statistical significance, the Mann-Whitney U-test was used. Practical significance was assessed using the effect of size.

RESULTS

All age groups of runners were selected to include individuals who run at least 10 km per week. In fact, they ran, on average, from 21.6 to 31.4 km per week in relation to age and showed significantly lower values of BM, BMI, BF, and VF (p < 0.05) than inactive individuals. Exceptions included insignificant differences (p > 0.05) in BM and BMI in males in the age category of 18-25 and in females in the age category of 18-25 and 26-35.

CONCLUSION

The selected runners had to run at least 10 km per week. Their actual average volume was significantly higher (from 21.6 to 31.4 km/week), and the results showed that it could lead to significantly better body composition values. It may lead to significant changes in body mass, body fat, and visceral fat. It may meet the contemporary societal expectations for physical activities that are both achievable and effective at the lowest possible volume.

The relationship between body mass index and stroke: a systemic review and meta-analysis

BACKGROUND

Stroke is an acute cerebrovascular event closely related to brain tissue damage, and is one of the major causes of death and disability in worldwide. Various studies have reported the effects of body mass index (BMI) on the risk of stroke, but the results remain varied and these results have not been synthesized. Therefore, a meta-analysis was performed to evaluate the relationship between BMI and the risk of stroke.

OBJECTIVES

This systematic review was conducted to explore the relationship between BMI and the risk of stroke.

METHODS

PubMed, EMBASE, Web of Science and Cochrane Library, China Knowledge Resource Integrated Database (CNKI), WanFang Database, Chinese Biomedical Database (CBM), and CQVIP were comprehensively searched for studies exploring the relationship between BMI and stroke from inception to December 1, 2021.

RESULTS

This review included 24 studies involving 5,798,826 subjects. The results of meta-analysis showed that the pooled RR of stroke risk was 0.93 (95% confidence interval [CI] 0.82-1.06, I² = 88.8%, P = 0.29) for the underweight group. Higher BMI (overweight or obese group) was associated with an increased overall risk of stroke, with pooled RR values of 1.25 (95% CI 1.16-1.34, I² = 84.8%, P = 0.00) and 1.47 (95% CI: 1.02-2.11, I² = 99.4%, P = 0.04).

CONCLUSION

The risk of stroke was positively correlated with BMI, and the association was stronger in male and ischemic stroke. Lowering BMI can be used as a way to prevent stroke, and for people who are overweight or obese, lowering body weight can reduce the risk of stroke.

Sex-specific association of BMI change with stroke in middle-aged and older adults with type 2 diabetes

BACKGROUND AND AIMS

We aimed to evaluate the association between BMI change and stroke in middle-aged and older adults with type 2 diabetes and identify sex differences.

METHODS AND RESULTS

The China Health and Retirement Longitudinal Study is an ongoing national population-based cohort study. Participants aged 45 or above with type 2 diabetes were enrolled and followed for stroke incidence. BMI change was defined as BMI at 2013-BMI at 2011. Of 1774 participants (mean [SD] age in 2011, 60.23 [8.88] years), 795 (44.8 %) were men. A total of 112 incident stroke cases were confirmed up to 2018. The incidence rate of stroke was similar between men and women (6.79 % vs 5.92 %, P = 0.516). BMI increase was independently associated with an increased stroke risk (adjusted odds ratio, 1.15; 95 % CI, 1.05-1.31) in men, while this positive association was not significant in women (adjusted odds ratio, 1.12; 95 % CI, 0.98-1.29). In addition, the positive dose-response relationship between BMI increase and stroke was observed only in men.

CONCLUSION

Among middle-aged and older adults with type 2 diabetes, there is a sex-specific association of BMI change with stroke. An increase in BMI could result in a higher risk of incident stroke in men.

Association between cardiometabolic index and stroke: A population-based cross-sectional study

BACKGROUND

Cardiometabolic index (CMI) is associated with several risk factors for stroke; however, few studies have assessed the role of CMI in stroke risk.

OBJECTIVE

This study aimed to assess the association between CMI and stroke in a population-based cross-sectional study.

METHODS

This study included 4445 general residents aged ≥40 years selected by multistage stratified random cluster sampling. CMI was calculated as the product of the ratio of waist circumference to height (WHtR) and the ratio of triglyceride levels to high-density lipoprotein cholesterol levels (TG/HDL-C). Participants were categorized according to CMI quartiles: quartile 1 (Q1), quartile 2 (Q2), quartile 3 (Q3), and quartile 4 (Q4). Multivariate logistic regression analysis and receiver operating characteristic (ROC) curves were used to assess the association between CMI and stroke.

RESULTS

A total of 4052 participants were included in the study, with an overall stroke prevalence of 7.2%. The prevalence of stroke increased with CMI quartiles, ranging from 4.4% to 9.2% (p for trend <0.001). Compared with Q1, stroke risk for Q2, Q3, and Q4 were 1.550-, 1.693-, and 1.704- fold, respectively. The area under the ROC curve (AUC) [95% CI] was (0.574 [0.558-0.589]) for CMI, 0.627 [0.612-0.642]) (p=0.0024) for WHtR, 0.556 [0.540-0.571]) (p<0.0001) for TG/HDL-C. CMI was inferior to WHtR, but CMI had marginal advantage over TG/HDL-C in terms of its stroke discrimination ability.

CONCLUSION

Although there was a strong and independent association between CMI and stroke in the general population, CMI had limited discriminating ability for stroke. Thus, new parameters should be developed.

Abdominal obesity and risk of CVD: a dose-response meta-analysis of thirty-one prospective studies

This meta-analysis aimed to study the relationship between abdominal obesity and the risk of CVD by waist circumference (WC), waist:hip ratio (WHR) and waist:height ratio (WHtR). We systematically searched PubMed, Embase and Web of Science. Prospective studies that estimated cardiovascular events by WC, WHR and WHtR were included in this study. Pooled relative risks with 95 % CI were calculated using random effects models. A total of thirty-one studies were included in the meta-analysis, including 669 560 participants and 25 214 cases. Compared the highest with the lowest category of WC, WHR and WHtR, the summary risk ratios were 1·43 (95 % CI, 1·30, 1·56, P < 0·001), 1·43 (95 % CI, 1·33, 1·54, P < 0·001) and 1·57 (95 % CI, 1·37, 1·79, P < 0·001), respectively. The linear dose-response analysis revealed that the risk of CVD increased by 3·4 % for each 10 cm increase of WC, and by 3·5 and 6·0 % for each 0·1 unit increase of WHR and WHtR in women, respectively. In men, the risk of CVD increased by 4·0 % for each 10 cm increase of WC, and by 4·0 and 8·6 % for each 0·1 unit increase of WHR and WHtR, respectively. Collectively, abdominal obesity is associated with an increased risk of CVD. WC, WHR and WHtR are good indicators for the prediction of CVD.

Effect of Central Obesity and Hyperandrogenism on Selected Inflammatory Markers in Patients with PCOS: A WHtR-Matched Case-Control Study

White blood cell counts (WBC), lymphocyte-to-monocyte ratio (LMR), and monocyte-to-high-density lipoprotein cholesterol ratio (MHR) are used as chronic inflammation markers. Polycystic ovary syndrome (PCOS) is a constellation of systemic inflammation linked to central obesity (CO), hyperandrogenism, insulin resistance, and metabolic syndrome. The waist-to-height ratio (WHtR) constitutes a highest-concordance anthropometric CO measure. This study aims to access WBC, LMR, and MHR in PCOS and healthy subjects, with or without CO. Establishing relationships between complete blood count parameters, high-sensitivity C-reactive protein (hsCRP), and hormonal, lipid and glucose metabolism in PCOS. To do this, WBC, LMR, MHR, hsCRP, anthropometric, metabolic, and hormonal data were analyzed from 395 women of reproductive age, with and without, PCOS. Correlations between MHR, and dysmetabolism, hyperandrogenism, and inflammation variables were examined. No differences were found in WBC, LMR, MHR, and hsCRP between PCOS and controls (p > 0.05). PCOS subjects with CO had higher hsCRP, MHR, and WBC, and lower LMR vs. those without CO (p < 0.05). WBC and MHR were also higher in controls with CO vs. without CO (p < 0.001). MHR correlated with anthropometric, metabolic, and endocrine parameters in PCOS. WHtR appeared to strongly predict MHR in PCOS. We conclude that PCOS does not independently influence WBC or MHR when matched for CO. CO and dysmetabolism may modify MHR in PCOS and control groups.

Obesity and cardiovascular disease in women

As the prevalence of obesity continues to grow worldwide, the health and financial burden of obesity-related comorbidities grows too. Cardiovascular disease (CVD) is clearly associated with increased adiposity. Importantly, women are at higher risk of CVD when obese and insulin resistant, in particular at higher risk of developing heart failure with preserved ejection fraction and ischemic heart disease. Increased aldosterone and mineralocorticoid receptor activation, aberrant estrogenic signaling and elevated levels of androgens are among some of the proposed mechanisms explaining the heightened CVD risk. In addition to traditional cardiovascular risk factors, understanding nontraditional risk factors specific to women, like excess weight gain during pregnancy, preeclampsia, gestational diabetes, and menopause are central to designing personalized interventions aimed to curb the epidemic of CVD. In the present review, we examine the available evidence supporting a differential cardiovascular impact of increased adiposity in women compared with men and the proposed pathophysiological mechanisms behind these differences. We also discuss women-specific cardiovascular risk factors associated with obesity and insulin resistance.

Sex influence in ischemic stroke severity and outcome among metabolically unhealthy overweight patients

INTRODUCTION

The role of metabolically unhealthy (MU) overweight in influencing stroke prognosis has not been fully assessed and conclusive data about the impact of sex are lacking. Aim of this study was to evaluate the possible correlations among MU overweight, sex and ischemic stroke severity and outcome.

METHODS

All consecutive patients with acute non-lacunar ischemic stroke observed over a one-year period were considered. MU subjects were selected and classified according to the body mass index (BMI) values. The relationships among sex, BMI and National Institutes of Health Stroke Scale (NIHSS) score at admission and modified Rankin scale (mRS) score at discharge were analysed with multivariate models.

RESULTS

180 patients were included. A significantly increasing trend in the NIHSS (p = .030) and in the mRS (p = .001) scores along with the increase of the BMI category was detected in women. Men showed a significantly decreasing trend in the NIHSS (p = .040) and a non-significant decreasing trend in the mRS (p = .290) scores with increasing BMI category.

CONCLUSIONS

Our findings show that sex can influence stroke severity and outcome among MU patients. The worse outcome observed in women suggest the need of considering differential sex-based clinical approaches in stroke overweight patients.

Baseline Obesity Increases 25-Year Risk of Mortality due to Cerebrovascular Disease: Role of Race

Background: Although obesity may have a role as a risk factor for cerebrovascular mortality, less is known about how demographic and social groups differ in this regard. Aims: This study had two aims: first to investigate the predictive role of baseline obesity on long-term risk of mortality due to cerebrovascular disease, and second, to test racial variation in this effect. Methods: the Americans’ Changing Lives Study (ACL) 1986–2011 is a state of the art 25-year longitudinal cohort study. ACL followed a nationally representative sample of Blacks (n = 1156) and Whites (n = 2205) for up to 25 years. Baseline obesity was the main predictor of interest, time to cerebrovascular death was the main outcome of interest. Demographic characteristics, socioeconomic status (educational attainment and household income), health behaviors (exercise and smoking), and health (hypertension and depressive symptoms) at baseline were covariates. Cox proportional hazards models were used to test additive and multiplicative effects of obesity and race on the outcome. Results: From the total 3,361 individuals, 177 people died due to cerebrovascular causes (Whites and Blacks). In the pooled sample, baseline obesity did not predict cerebrovascular mortality (hazard ratio (HR) = 0.86, 0.49–1.51), independent of demographic, socioeconomic, health behaviors, and health factors at baseline. Race also interacted with baseline obesity on outcome (HR = 3.17, 1.09–9.21), suggesting a stronger predictive role of baseline obesity on cerebrovascular deaths for Black people compared to White individuals. According to the models that were run specific to each race, obesity predicted risk of cerebrovascular mortality for Blacks (HR = 2.51, 1.43–4.39) but not Whites (HR = 0.69, 0.31–1.53). Conclusions: Baseline obesity better predicts long-term risk of cerebrovascular death in Black individuals compared to White people. More research should explore factors that explain why racial differences exist in the effects of obesity on cerebrovascular outcome. Findings also have implications for personalized medicine.

Derivation and validation of a new visceral adiposity index for predicting visceral obesity and cardiometabolic risk in a Korean population

Objectives

The visceral adiposity index (VAI), an indirect marker of visceral adipose tissue, serves as a model associated with cardiometabolic risk, but has limitations regarding the Asian population. We sought to develop a new VAI (NVAI) for the Korean population and compare it to VAI for prediction of atherosclerotic cardiovascular disease (ASCVD) risk and development of major cardiovascular diseases (CVD) and stroke.

Methods

Patients (969) who underwent visceral fat area measurement were analyzed. After exclusion, 539 patients (142 men, 397 women) were randomly divided into internal (n = 374) and external validation (n = 165) data set. The NVAI was developed using univariate and multivariate logistic regression with backward selection of predictors. Receiver operating characteristic (ROC) curve analysis and comparison of the area under the curve (AUC) verified the better predictor of ASCVD risk score. Additionally, nationwide population-based cross-sectional survey data (Korean National Health and Nutrition Examination Survey [KNHANES] 2008–2010, n = 29,235) was used to validate the NVAI’s ability to predict ASCVD risk and major CVD and stroke.

Results

The NVAI better reflected visceral fat area in internal and external data sets, with AUCs of 0.911 (95% confidence interval [CI]: 0.882–0.940) and 0.879 (95% CI: 0.828–0.931), respectively. NVAI better discriminated for ASCVD risk (AUC = 0.892, 95% CI: 0.846–0.938) compared to VAI (0.559, 95% CI: 0.439–0.679). The NVAI also better predicted MI or angina, and stroke with AUCs of 0.771 (95% CI: 0.752–0.789), and 0.812 (95% CI: 0.794–0.830), respectively, compared with waist circumference (WC), body mass index (BMI), TG to HDL ratio, and VAI via KNHANES, in a statistically significant manner.

Conclusions

The NVAI has advantages as a predictor of visceral obesity and is significantly associated with ASCVD risks and development of major CVD and stroke in the Korean population. The NVAI could be a screening tool for improved risk estimation related to visceral obesity.

Associations between anthropometric parameters and lipid profiles in Chinese individuals with age ≥40 years and BMI <28kg/m2

BACKGROUND

Lipid abnormalities are associated with overweight and obesity. Some simple anthropometric measurements such as body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHpR), and waist-to-height ratio (WHtR), may link to increased risk of dyslipidemia. However, diverse results were found in different population studies. We focused on the associations between these measurements and dyslipidemia in non-obese (BMI <28kg/m2) population aged more than 40 years.

METHODS AND FINDINGS

Cross-sectional study of 4185 non-obese adults aged more than 40 years was conducted in Nanchang, Jiangxi province, China. Questionnaire, anthropometric and laboratory tests were conducted. The National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III) criteria were used to define high total cholesterol (TC), high low-density lipoprotein cholesterol (LDL-C), low high-density lipoprotein cholesterol (HDL-C), hypertriglyceridemia and dyslipidemia. The overall prevalence of high TC, high LDL-C, low HDL-C, hypercholesterolemia, hypertriglyceridemia and dyslipidemia were 15.68%, 27.98%, 20.12%, 44.01%, 21.98% and 49.06% respectively. Multiple logistic regressions showed only BMI (per quartile increment) increased risks for prevalent high LDL-C, low HDL-C, hypercholesterolemia, hypertriglyceridemia, and dyslipidemia. Regardless of sex, age and prevalent metabolic syndrome, increasing BMI was persistently independent risk factor for having low HDL-C, hypercholesterolemia and dyslipidemia, however was not associated with high TC.

CONCLUSIONS

In non-obese Chinese population aged more than 40 years, increasing BMI may better identify the prevalent dyslipidemia than other anthropometric measurements. However, due to the different meanings, both BMI and WC should be measured and monitored for metabolic risk assessment.

Statistical evaluation of adding multiple risk factors improves Framingham stroke risk score

BACKGROUND

Framingham Stroke Risk Score (FSRS) is the most well-regarded risk appraisal tools for evaluating an individual's absolute risk on stroke onset. However, several widely accepted risk factors for stroke were not included in the original Framingham model. This study proposed a new model which combines an existing risk models with new risk factors using synthesis analysis, and applied it to the longitudinal Atherosclerosis Risk in Communities (ARIC) data set.

METHODS

Risk factors in original prediction models and new risk factors in proposed model had been discussed. Three measures, like discrimination, calibration and reclassification, were used to evaluate the performance of the original Framingham model and new risk prediction model.

RESULTS

Modified C-statistics, Hosmer-Lemeshow Test and classless NRI, class NRI were the statistical indices which, respectively, denoted the performance of discrimination, calibration and reclassification for evaluating the newly developed risk prediction model on stroke onset. It showed that the NEW-STROKE (new stroke risk score prediction model) model had higher modified C-statistics, smaller Hosmer-Lemeshow chi-square values after recalibration than original FSRS model, and the classless NRI and class NRI of the NEW-STROKE model over the original FSRS model were all significantly positive in overall group.

CONCLUSION

The NEW-STROKE integrated with seven literature-derived risk factors outperformed the original FSRS model in predicting the risk score of stroke. It illustrated that seven literature-derived risk factors contributed significantly to stroke risk prediction.

Body mass index and stroke incidence in Japanese community residents: The Jichi Medical School (JMS) Cohort Study

BACKGROUND

High body mass index (BMI) has been reported as a risk factor for cardiovascular events in Western countries, while low BMI has been reported as a risk factor for cardiovascular death in Asian countries, including Japan. Although stroke is a major cause of death and disability in Japan, few cohort studies have examined the association between BMI and stroke incidence in Japan. This study aimed to examine the association between BMI and stroke incidence using prospective data from Japanese community residents.

METHODS

Data were analyzed from 12,490 participants in the Jichi Medical School Cohort Study. Participants were categorized into five BMI groups: ≤18.5, 18.6-21.9, 22.0-24.9, 25.0-29.9, and ≥30.0 kg/m². Multivariate-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using the Cox proportional hazard model. The group with a BMI of 22.0-24.9 kg/m² was used as the reference category.

RESULTS

During mean follow-up of 10.8 years, 395 participants (207 men and 188 women) experienced stroke, including 249 cerebral infarctions and 92 cerebral hemorrhages. Men with a BMI ≤18.5 kg/m² (HR 2.11; 95% CI, 1.17-3.82) and women with a BMI ≥30.0 kg/m² (HR 2.25; 95% CI, 1.28-5.08) were at significantly higher risk for all-stroke. Men with a BMI ≤18.5 kg/m² were at significantly higher risk for cerebral infarction (HR 2.15; 95% CI, 1.07-4.33).

CONCLUSIONS

The association between BMI and stroke incidence observed in this population was different than those previously reported: low BMI was a risk factor for all-stroke and cerebral infarction in men, while high BMI was a risk factor for all-stroke in women.

Waist-to-height ratio is an effective indicator for comprehensive cardiovascular health

The aim of this study was to determine the associations between cardiovascular health and the waist circumference (WC) and waist-to-height ratio (WHtR). A cross-sectional study was performed recruiting 26701 middle-aged Chinese men. Of the seven ideal cardiovascular health metrics, body mass index (BMI), total cholesterol (TC), blood pressure (BP), and fasting blood glucose (FBG) were found to increase with an elevation of the mean WC and WHtR. The mean WC and WHtR were significantly lower in the subjects with intermediate or ideal cardiovascular health than those with poor or intermediate health. After adjustment for age, the mean WC and WHtR decreased by 1.486 cm and 0.009 per 1-point increase in the cardiovascular health score, and 2.242 cm and 0.013 per 1-point increase in the number of ideal cardiovascular health metrics, respectively. The cardiovascular health score was negatively correlated with the WC (r = -0.387) and WHtR (r = -0.400), while the number of ideal cardiovascular health metrics was negatively associated with the WC (r = -0.384) and WHtR (r = -0.395). The cardiovascular health is correlated negatively with the WC and WHtR, and a stronger correlation existed between the cardiovascular health and WHtR than WC.

Obesity and stroke: Can we translate from rodents to patients?

Obesity is a risk factor for stroke and is consequently one of the most common co-morbidities found in patients. There is therefore an identified need to model co-morbidities preclinically to allow better translation from bench to bedside. In preclinical studies, both diet-induced and genetically obese rodents have worse stroke outcome, characterised by increased ischaemic damage and an altered inflammatory response. However, clinical studies have reported an 'obesity paradox' in stroke, characterised by reduced mortality and morbidity in obese patients. We discuss the potential reasons why the preclinical and clinical studies may not agree, and review the mechanisms identified in preclinical studies through which obesity may affects stroke outcome. We suggest inflammation plays a central role in this relationship, as obesity features increases in inflammatory mediators such as C-reactive protein and interleukin-6, and chronic inflammation has been linked to worse stroke risk and outcome.

Waist-to-height ratio as a screening tool for obesity and cardiometabolic risk

The waist-to-height ratio (WHtR), calculated by dividing the waist circumference (WC) by height, has recently gained attention as an anthropometric index for central adiposity. It is an easy-to-use and less age-dependent index to identify individuals with increased cardiometabolic risk. A WHtR cutoff of 0.5 can be used in different sex and ethnic groups and is generally accepted as a universal cutoff for central obesity in children (aged ≥6 years) and adults. However, the WHtR has not been validated in preschool children, and the routine use of WHtR in children under age 6 is not recommended. Prospective studies and meta-analysis in adults revealed that the WHtR is equivalent to or slightly better than WC and superior to body mass index (BMI) in predicting higher cardiometabolic risk. In children and adolescents, studies have shown that the WHtR is similar to both BMI and WC in identifying those at an increased cardiometabolic risk. Additional use of WHtR with BMI or WC may be helpful because WHtR considers both height and central obesity. WHtR may be preferred because of its simplicity and because it does not require sex- and age-dependent cutoffs; additionally, the simple message 'keep your WC to less than half your height' may be particularly useful. This review article summarizes recent publications on the usefulness of using WHtR especially when compared to BMI and WC as a screening tool for obesity and related cardiometabolic risks, and recommends the use of WHtR in clinical practice for obesity screening in children and adolescents.

Overweight and Obesity in Young Adulthood and the Risk of Stroke: a Meta-analysis

BACKGROUND

A systematic review assessing the association between overweight and obesity in young adulthood and stroke risk is lacking. Therefore, we conducted a meta-analysis to evaluate the association between overweight and obesity in young adulthood and stroke risk.

METHODS

We systematically searched PubMed and Embase databases for related studies of human subjects in the English language. Two investigators independently selected original studies in a 2-step process. Fixed- and random-effects models were used to calculate pooled relative risks (RRs) and 95% confidence intervals (CIs). Subgroup analyses were also performed.

RESULTS

Eight studies met the inclusion criteria. The pooled adjusted RR of stroke was 1.36 (95% CI: 1.28-1.44) for overweight in young adulthood and 1.81 (95% CI: 1.45-2.25) for obesity in young adulthood. In subgroup analyses, overweight and obesity in young adulthood increased the risk of stroke in most groups, except for the group of stroke subtype. For ischemic stroke, the adjusted RR was 1.40 (95% CI: 1.24-1.58) for overweight in young adulthood and 1.78 (95% CI: 1.003-3.16) for obesity in young adulthood, whereas adjusted RR for hemorrhagic stroke was 1.25 (95% CI: .83-1.90) for overweight in young adulthood and 1.80 (95% CI: .97-3.35) for obesity in young adulthood.

CONCLUSIONS

Overweight and obesity in young adulthood are associated with an increased risk of stroke, probably, independent of other cardiovascular risk factors. The risk effect gradually increases with increasing body weight.

Obesity and Abdominal Fat Markers in Patients with a History of Stroke and Transient Ischemic Attacks

BACKGROUND

Abdominal obesity is a well-recognized cardiovascular risk factor. Conflicting data concerning its significance with respect to stroke have been discussed in recent years. The objective of this study was to analyze the association between anthropometric parameters and the risk of stroke and transient ischemic attacks (TIAs) in German primary care.

METHODS

Patient recruitment in this large-scale epidemiological study was performed in 3188 representative primary care offices in Germany. Among 6980 study participants, 1745 patients with a history of stroke or TIA were identified and matched for age and gender with 5235 regional controls. Associations between standard anthropometric measures such as body mass index (BMI), waist-to-hip ratio, waist circumference, waist-to-height ratio, and cerebrovascular risk were investigated using logistic regression analysis with adjustment for age, gender, and vascular risk factors.

RESULTS

BMI showed no significant associations with the risk of stroke or TIA in any of the applied mathematical models. Markers of abdominal obesity were associated with an increased risk of stroke or TIA in the unadjusted model (waist circumference: odds ratio [OR] 1.15; 95% confidence interval [CI], 1.00-1.32; waist-to-hip ratio: OR 1.21; 95% CI, 1.05-1.38; waist-to-height ratio: OR 1.25; 95% CI, 1.09-1.44, comparisons between top and bottom tertiles). After adjustment for vascular risk factors, all associations were insignificant.

CONCLUSIONS

Abdominal obesity is a stronger predictor of risk of stroke or TIA than BMI. However, the association between abdominal obesity and the risk of stroke or TIA is not independent of other vascular risk factors. Stroke-related weight changes should be considered in longitudinal studies examining the role of obesity in cerebrovascular disease.

Echocardiographic epicardial fat thickness and neutrophil to lymphocyte ratio are novel inflammatory predictors of cerebral ischemic stroke

BACKGROUND

The role of epicardial fat thickness (EFT) in ischemic stroke (IS) has not been previously investigated. The aim of the present study was to evaluate EFT and neutrophil/lymphocyte ratio (NLR) among patients with IS and to examine the relationship between these inflammatory markers and the incidence of IS.

METHODS

The cross-sectional design includes 38 patients with IS and 47 age- and sex-matched healthy controls. Echocardiographic measurement of EFT was conducted according to previously published methods. An automated hematology analyzer was used to generate total and differential leukocyte counts from patient blood samples.

RESULTS

Mean EFT was 4.86 ± .68 mm in the control group and 5.95 ± 1.14 mm in the IS group. EFT was significantly greater in the IS patients in relation to the control group (P < .001). Mean NLR was significantly greater among IS patients in relation to the control group (2.5 ± .6 vs. 1.8 ± .4, P < .001). No significant confounding factors were identified in the data set. Spearman's correlation analysis revealed a mild, but highly significant correlation between EFT and NLR (r = .293, P = .006).

CONCLUSIONS

This study demonstrates for the first time the association between EFT and cerebral IS. Echocardiographic EFT was significantly correlated with NLR. NLR and echocardiographic EFT represent inexpensive and readily available clinical markers that maybe useful in estimating risk of IS.

A pooled analysis of waist circumference and mortality in 650,000 adults

OBJECTIVES

To assess the independent effect of waist circumference on mortality across the entire body mass index (BMI) range and to estimate the loss in life expectancy related to a higher waist circumference.

PATIENTS AND METHODS

We pooled data from 11 prospective cohort studies with 650,386 white adults aged 20 to 83 years and enrolled from January 1, 1986, through December 31, 2000. We used proportional hazards regression to estimate hazard ratios (HRs) and 95% CIs for the association of waist circumference with mortality.

RESULTS

During a median follow-up of 9 years (maximum, 21 years), 78,268 participants died. After accounting for age, study, BMI, smoking status, alcohol consumption, and physical activity, a strong positive linear association of waist circumference with all-cause mortality was observed for men (HR, 1.52 for waist circumferences of ≥110 vs <90 cm; 95% CI, 1.45-1.59; HR, 1.07 per 5-cm increment in waist circumference; 95% CI, 1.06-1.08) and women (HR, 1.80 for waist circumferences of ≥95 vs <70 cm; 95% CI, 1.70-1.89; HR, 1.09 per 5-cm increment in waist circumference; 95% CI, 1.08-1.09). The estimated decrease in life expectancy for highest vs lowest waist circumference was approximately 3 years for men and approximately 5 years for women. The HR per 5-cm increment in waist circumference was similar for both sexes at all BMI levels from 20 to 50 kg/m(2), but it was higher at younger ages, higher for longer follow-up, and lower among male current smokers. The associations were stronger for heart and respiratory disease mortality than for cancer.

CONCLUSIONS

In white adults, higher waist circumference was positively associated with higher mortality at all levels of BMI from 20 to 50 kg/m(2). Waist circumference should be assessed in combination with BMI, even for those in the normal BMI range, as part of risk assessment for obesity-related premature mortality.

Guidelines for the prevention of stroke in women: a statement for healthcare professionals from the American Heart Association/American Stroke Association

PURPOSE

The aim of this statement is to summarize data on stroke risk factors that are unique to and more common in women than men and to expand on the data provided in prior stroke guidelines and cardiovascular prevention guidelines for women. This guideline focuses on the risk factors unique to women, such as reproductive factors, and those that are more common in women, including migraine with aura, obesity, metabolic syndrome, and atrial fibrillation.

METHODS

Writing group members were nominated by the committee chair on the basis of their previous work in relevant topic areas and were approved by the American Heart Association (AHA) Stroke Council's Scientific Statement Oversight Committee and the AHA's Manuscript Oversight Committee. The panel reviewed relevant articles on adults using computerized searches of the medical literature through May 15, 2013. The evidence is organized within the context of the AHA framework and is classified according to the joint AHA/American College of Cardiology and supplementary AHA Stroke Council methods of classifying the level of certainty and the class and level of evidence. The document underwent extensive AHA internal peer review, Stroke Council Leadership review, and Scientific Statements Oversight Committee review before consideration and approval by the AHA Science Advisory and Coordinating Committee.

RESULTS

We provide current evidence, research gaps, and recommendations on risk of stroke related to preeclampsia, oral contraceptives, menopause, and hormone replacement, as well as those risk factors more common in women, such as obesity/metabolic syndrome, atrial fibrillation, and migraine with aura.

CONCLUSIONS

To more accurately reflect the risk of stroke in women across the lifespan, as well as the clear gaps in current risk scores, we believe a female-specific stroke risk score is warranted.

Anthropometric measurements of general and central obesity and the prediction of cardiovascular disease risk in women: a cross-sectional study

OBJECTIVES

It is important to ascertain which anthropometric measurements of obesity, general or central, are better predictors of cardiovascular disease (CVD) risk in women. 10-year CVD risk was calculated from the Framingham risk score model, SCORE risk chart for high-risk regions, general CVD and simplified general CVD risk score models. Increase in CVD risk associated with 1 SD increment in each anthropometric measurement above the mean was calculated, and the diagnostic utility of obesity measures in identifying participants with increased likelihood of being above the treatment threshold was assessed.

DESIGN

Cross-sectional data from the National Heart Foundation Risk Factor Prevalence Study.

SETTING

Population-based survey in Australia.

PARTICIPANTS

4487 women aged 20-69 years without heart disease, diabetes or stroke.

OUTCOME MEASURES

Anthropometric obesity measures that demonstrated the greatest increase in CVD risk as a result of incremental change, 1 SD above the mean, and obesity measures that had the greatest diagnostic utility in identifying participants above the respective treatment thresholds of various risk score models.

RESULTS

Waist circumference (WC), waist-to-hip ratio (WHR) and waist-to-stature ratio had larger effects on increased CVD risk compared with body mass index (BMI). These central obesity measures also had higher sensitivity and specificity in identifying women above and below the 20% treatment threshold than BMI. Central obesity measures also recorded better correlations with CVD risk compared with general obesity measures. WC and WHR were found to be significant and independent predictors of CVD risk, as indicated by the high area under the receiver operating characteristic curves (>0.76), after controlling for BMI in the simplified general CVD risk score model.

CONCLUSIONS

Central obesity measures are better predictors of CVD risk compared with general obesity measures in women. It is equally important to maintain a healthy weight and to prevent central obesity concurrently.

Effect of exercise intervention on changes in free Fatty Acid levels and metabolic risk factors in stroke patients

[Purpose] The present study investigated the effects of regular exercise on the improvement of free fatty acid (FFA) levels and metabolic risk factors of stroke patients. [Methods] The subjects were 20 male patients aged 47-59 years who were diagnosed as having hemiplegia resulting from stroke. Exercise was conducted using a stationary bicycle, a rehabilitative exercise machine. The exercise program utilized the heart rate reserve (HRR) method to create an exercise intensity amounting to 50-70% of the target heart rate (THR). The program lasted for 30 minutes and was conducted 5 times per week for a total of 12 weeks. [Results] In stroke patients, 12 weeks of exercise training yielded a significant interaction effect with weight, body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR). There were also significant differences in triglycerides (TG) according to the time of measurement, and an interaction effect was observed for triglycerides (TC). High-density lipoprotein cholesterol (HDLC), an important marker of improvement in metabolic risk factors, showed a significant interaction effect with exercise training. In addition, free fatty acids (FFA) showed a significant difference based on the time of measurement and showed a significant negative correlation with HDLC (r = -0.77). [Conclusion] The results of the present study suggest that regular exercise by stroke patients reduces their risk of metabolic complications and stroke recurrence by reducing obesity indices, improving serum lipid and FFA levels, and increasing HDLC levels.

Genetic determinants of obesity and related vascular diseases

Obesity is one of the major risk factors of vascular diseases, and its prevalence is increasing worldwide. In the past decade, progress has been made in the understanding of genetic determinants of obesity and obesity-associated diseases. Genome-wide association studies identified a number of genetic variants associated with obesity. In addition to common variants, FTO and MC4R, new loci, such as TMEM18, KCTD15, GNPDA2, SH2B1, MTCH2, and NEGR1 have been detected. In the past years, abdominal obesity has been shown to be a more important vascular risk factor than the body mass index. In the context of vascular risk assessment, identification of genetic polymorphisms associated with accumulation of visceral fat is of special importance. Some polymorphisms associated with abdominal obesity, such as variants of gene encoding microsomal triglyceride transfer protein, have been already discovered. In this chapter, we provide a review of genetic determinants of obesity and discuss their role in obesity-related vascular diseases.

Insulin resistance, obesity, metabolic syndrome, and lifestyle modification

PURPOSE OF REVIEW

: This article provides an overview of the effects of obesity, metabolic syndrome, and insulin resistance on stroke risk; outlines the association between healthy lifestyle habits and stroke; and summarizes features of effective lifestyle interventions.

RECENT FINDINGS

: General obesity, abdominal obesity, insulin resistance, and the metabolic syndrome are all independently linked with stroke risk and may worsen outcomes after stroke. Five key lifestyle factors-regular exercise, abstinence from smoking, a diet rich in fruits and vegetables, a body mass index of 18.5 to 24.9 kg/m, and moderate alcohol use-have been shown to lower the risk of stroke. Collaborative, multidisciplinary, intensive, patient-centered interventions tend to be the most effective for lifestyle change.

SUMMARY

: Mounting obesity rates are threatening the gains that have been made in reducing stroke incidence through traditional risk factor control. In order to mitigate the burden of stroke, physicians need to regularly address lifestyle factors when caring for patients.

Epigenetic manifestation of metabolic syndrome and dietary management

SIGNIFICANCE

Metabolic syndrome constitutes a group of disorders such as insulin resistance, hypertension, and hypertriglyceridemia, predisposing an individual to risk factors such as cardiovascular disease, diabetes, obesity, and dyslipidemia. A majority of these diseases are influenced by the environmental factors, nutrient uptake, and genetic profile of an individual that together dysregulate gene function. These genetic and nongenetic factors are reported to introduce epigenetic cues that modulate the gene function which is inherited by the offspring.

RECENT ADVANCES

Considering the epigenetic modulation of the metabolic disorders, nutrigenomics has been distinctly categorized as a branch that deals with modulatory effect of nutrients on metabolic disorders and disease progression by supplementing the individuals with key nutrient-enriched diets which are derived from plant and animal sources.

CRITICAL ISSUES

Nutritional components of the diet regulate the metabolic health of an individual either by controlling the expression of some key genes related to metabolic pathways or by modulating the epigenetic events on such genes. The present article discusses various metabolic disorders in detail and the effect of nutrients on the specific genes causing those disorders. We also highlight the molecular mechanisms of some metabolic disorders through epigenetic modifications and possible therapeutic interventions.

FUTURE DIRECTIONS

With the advent of high-throughput technologies and epigenetic modulation of the metabolic disorders, an altered epigenetic code that is programmed due to improper nutrients can be reverted back by supplementing the diet with various plant-derived compounds. The implication of small molecular drugs is also of utmost significance for challenging the metabolic disorders.

Waist-to-height ratio is a better screening tool than waist circumference and BMI for adult cardiometabolic risk factors: systematic review and meta-analysis

Our aim was to differentiate the screening potential of waist-to-height ratio (WHtR) and waist circumference (WC) for adult cardiometabolic risk in people of different nationalities and to compare both with body mass index (BMI). We undertook a systematic review and meta-analysis of studies that used receiver operating characteristics (ROC) curves for assessing the discriminatory power of anthropometric indices in distinguishing adults with hypertension, type-2 diabetes, dyslipidaemia, metabolic syndrome and general cardiovascular outcomes (CVD). Thirty one papers met the inclusion criteria. Using data on all outcomes, averaged within study group, WHtR had significantly greater discriminatory power compared with BMI. Compared with BMI, WC improved discrimination of adverse outcomes by 3% (P < 0.05) and WHtR improved discrimination by 4-5% over BMI (P < 0.01). Most importantly, statistical analysis of the within-study difference in AUC showed WHtR to be significantly better than WC for diabetes, hypertension, CVD and all outcomes (P < 0.005) in men and women. For the first time, robust statistical evidence from studies involving more than 300 000 adults in several ethnic groups, shows the superiority of WHtR over WC and BMI for detecting cardiometabolic risk factors in both sexes. Waist-to-height ratio should therefore be considered as a screening tool.

No Time to ‘Weight’: The Link between Obesity and Stroke in Women

The obesity epidemic in the USA threatens the gains that have been made in the prevention and treatment of stroke. Both obesity and stroke disproportionately affect women more than men. Understanding the effect of obesity on stroke risk in women may be a useful stepping stone to reducing the burden of stroke in this vulnerable population. This article reviews the association between stroke and general obesity, abdominal obesity and metabolic syndrome in women. All three factors have been shown to independently increase stroke risk in women.

Persistent sex disparity in midlife stroke prevalence in the United States

BACKGROUND

A recent study found that US women aged 45-54 years in 1999-2004 were twice as likely as men to report previous stroke. The aim of this study was to evaluate the validity of this finding by assessing the sex-specific midlife stroke prevalence in the most recent nationally representative, cross-sectional sample of US individuals.

METHODS

Sex-specific stroke prevalence, sex-specific vascular risk factor prevalence and sex-specific independent predictors of stroke were assessed among 35- to 64-year olds who participated in the National Health and Nutrition Examination Surveys in 2005-2006 (n = 2,274).

RESULTS

Women aged 35-64 years were almost 3 times more likely than men to report prior stroke (2.90 vs. 1.07%; p < 0.001). This disparity was driven by the 45- to 54-year age group, where women had thrice the odds of prior stroke compared with men (OR 3.12, 95% CI 1.30-7.50). Among 45- to 54-year olds, men were more likely than women to have a history of smoking, elevated homocysteine and elevated triglyceride levels, but less likely to be abdominally obese (p < 0.001). Independent stroke risk factors among women aged 35-64 years were a homocysteine level >8.5 μmol/l (OR 6.19, 95% CI 2.57-14.93), a history of myocardial infarction (OR 5.35, 95% CI 1.09-26.27) and diabetes mellitus (OR 6.63, 95% CI 2.47-17.81).

CONCLUSION

The midlife sex disparity in US stroke prevalence persists. Greater emphasis on prompt recognition and treatment of cardiovascular risk factors among young and middle-aged women may ameliorate this worrisome trend.

Program of rehabilitative exercise and education to avert vascular events after non-disabling stroke or transient ischemic attack (PREVENT Trial): a multi-centred, randomised controlled trial

BACKGROUND

Despite lack of outward signs, most individuals after non-disabling stroke (NDS) and transient ischemic attack (TIA) have significant cardiovascular and cerebrovascular disease and are at high risk of a major stroke, hospitalization for other vascular events, or death. Most have multiple modifiable risk factors (e.g., hypertension, physical inactivity, hyperlipidaemia, diabetes, tobacco consumption, psychological stress). In addition, accelerated rates of depression, cognitive decline, and poor quality of sleep have been reported following TIA, which correlate with poor functional outcomes and reduced quality of life. Thus, NSD and TIA are important warning signs that should not be overlooked. The challenge is not unlike that facing other 'silent' conditions - to identify a model of care that is effective in changing people's current behaviors in order to avert further morbidity.

METHODS/DESIGN

A single blind, randomized controlled trial will be conducted at two sites to compare the effectiveness of a program of rehabilitative exercise and education versus usual care in modifying vascular risk factors in adults after NDS/TIA. 250 adults within 90 days of being diagnosed with NDS/TIA will be randomly allocated to a 12-week program of exercise and education (PREVENT) or to an outpatient clinic assessment and discussion of secondary prevention recommendations with return clinic visits as indicated (USUAL CARE). Primary outcome measures will include blood pressure, waist circumference, 12-hour fasting lipid profile, and 12-hour fasting glucose/hemoglobin A1c. Secondary measures will include exercise capacity, walking endurance, physical activity, cognitive function, depression, goal attainment and health-related quality of life. Outcome assessment will be conducted at baseline, post-intervention, and 6- and 12-month follow-ups. Direct health care costs incurred over one year by PREVENT versus USUAL CARE participants will also be compared. Ethical approval for the trial has been obtained from the relevant Human Research Ethics Boards.

DISCUSSION

Whether timely delivery of an adapted cardiac rehabilitation model is effective in attaining and maintaining vascular risk reduction targets in adults after NDS/TIA is not yet known. We anticipate that the findings of this trial will make a meaningful contribution to the knowledge base regarding secondary stroke prevention.

Adult height and the risk of cardiovascular disease among middle aged men and women in Japan

An inverse association between height and risk of cardiovascular disease has been reported, but the evidence is limited for stroke subtypes, in particular in Asian populations. Further, few studies have examined how socioeconomic status in adulthood influence the relationship between height and risk of cardiovascular disease. This study examined the association between height and risks of stroke and coronary heart disease, and whether education level, an indicator of adult socioeconomic status, modify the effect of height on those risks, within a cohort of the Japan Public Health Center-based Prospective Study (JPHC Study). The hazard ratios for the incidence of cardiovascular disease associated with height were calculated by a 16-year follow-up of 15,564 Japanese men and women, aged 40-59. The hazard ratios were adjusted for age, gender, area, education, occupation and cardiovascular risk factors. Height was inversely associated with risks of total stroke, either hemorrhagic or ischemic stroke but not with coronary heart disease. The adjusted hazard ratios (95% confidence interval (CI)) of total stroke, hemorrhagic stroke, and ischemic stroke for a 1 SD height increments were 0.82 (95% CI: 0.74, 0.90), 0.80 (95% CI: 0.70, 0.92), and 0.83 (95% CI: 0.73, 0.95), respectively. No multiplicative interaction was observed between height and education level on stroke risk. Short stature was associated with increased risk of total stroke, either hemorrhagic or ischemic stroke, independent of adult socioeconomic status and cardiovascular risk factors, but not with risk of coronary heart disease in Japanese men and women.

A systematic review of waist-to-height ratio as a screening tool for the prediction of cardiovascular disease and diabetes: 0·5 could be a suitable global boundary value

This systematic review collated seventy-eight studies exploring waist-to-height ratio (WHtR) and waist circumference (WC) or BMI as predictors of diabetes and CVD, published in English between 1950 and 2008. Twenty-two prospective analyses showed that WHtR and WC were significant predictors of these cardiometabolic outcomes more often than BMI, with similar OR, sometimes being significant predictors after adjustment for BMI. Observations from cross-sectional analyses, forty-four in adults, thirteen in children, supported these predictions. Receiver operator characteristic (ROC) analysis revealed mean area under ROC (AUROC) values of 0·704, 0·693 and 0·671 for WHtR, WC and BMI, respectively. Mean boundary values for WHtR, covering all cardiometabolic outcomes, from studies in fourteen different countries and including Caucasian, Asian and Central American subjects, were 0·50 for men and 0·50 for women. WHtR and WC are therefore similar predictors of diabetes and CVD, both being stronger than, and independent of, BMI. To make firmer statistical comparison, a meta-analysis is required. The AUROC analyses indicate that WHtR may be a more useful global clinical screening tool than WC, with a weighted mean boundary value of 0·5, supporting the simple public health message 'keep your waist circumference to less than half your height'.

Urgency of reassessment of role of obesity indices for metabolic risks

The definition of metabolic syndrome places emphasis on health care for persons at risk. However, whether an obesity index should be a mandatory component of the definition and whether obesity indices can identify metabolic risks satisfactorily require further exploration. Therefore, we investigated the effectiveness of various anthropometric obesity indices in identifying the clustering of 2 or more American Heart Association (AHA)/National Heart, Lung, and Blood Institute (NHLBI)/International Diabetes Federation (IDF)-defined metabolic risk factors (hypertension, hyperglycemia, hypertriglyceridemia, and low high-density lipoprotein cholesterol) for metabolic syndrome and those of other metabolic risk factors (high low-density lipoprotein cholesterol, hyperuricemia, high gamma-glutamyltransferase, fatty liver) in 6141 men and 2137 women. The anthropometric indices were the following: (1) for both sexes--various levels of waist-to-height ratio (WHtR) including 0.5 and body mass index (BMI) of 23 and 25 kg/m(2); (2) for men and women individually--waist circumference (W) 90/80 cm (AHA/NHLBI/IDF for ethnic groups), W 85/90 cm (Japan Society for the Study of Obesity), and combined W and BMI: W 85/90 cm and/or BMI 25 kg/m(2) (Japanese government). The results showed the following: (1) The optimal value for WHtR was 0.5 for AHA/NHLBI/IDF-defined risk factors and approximately 0.5 for other risk factors in both sexes. (2) The sensitivities of various proposed obesity indices for identifying clustering of defined and other risk factors varied between 74.4% (WHtR 0.5) and 36.3% (BMI 25) and between 80.5% (WHtR 0.5) and 43.7% (BMI 25) in men, and varied between 65.6% (WHtR 0.5) and 16.8% (W 90 cm) and between 82.3% (WHtR 0.5) and 28.2% (W 90 cm) in women. Because the sensitivities of many anthropometric indices were very low, a reassessment of the effectiveness of obesity indices in evaluating metabolic risks and especially their suitability as a single mandatory component of metabolic syndrome is urgently needed. However, WHtR 0.5 provides a very useful algorithm for screening persons at risk.

Excess body weight and incidence of stroke: meta-analysis of prospective studies with 2 million participants

BACKGROUND AND PURPOSE

A systematic review of the prospective studies addressing the relationship of overweight and obesity to major stroke subtypes is lacking. We evaluated the occurrence of a graded association between overweight, obesity, and incidence of ischemic and hemorrhagic stroke by a meta-analysis of cohort studies.

METHODS

A search of online databases and relevant reviews was performed. Inclusion criteria were original article in English, prospective study design, follow-up > or = 4 years, indication of number of subjects exposed, and number of events across body mass index categories. Crude unadjusted relative risk (RR) and 95% CI were calculated for each study for overweight or obese compared with normal-weight categories. Log-transformed values and SE were used to calculate the pooled RR with random effects models; publication bias was checked. Additional analyses were performed using the multivariate estimates of risk reported in the individual studies.

RESULTS

Twenty-five studies were included, with 2 274 961 participants and 30 757 events. RR for ischemic stroke was 1.22 (95% CI, 1.05-1.41) for overweight and 1.64 (95% CI, 1.36-1.99) for obesity, whereas RR for hemorrhagic stroke was 1.01 (95% CI, 0.88-1.17) and 1.24 (95% CI, 0.99-1.54), respectively. Subgroup and meta-regression analyses ruled out gender, population average age, body mass index and blood pressure, year of recruitment, year of study publication, and length of follow-up as significant sources of heterogeneity. The additional analyses relying on the published multivariate estimates of risk provided qualitatively similar results.

CONCLUSIONS

Overweight and obesity are associated with progressively increasing risk of ischemic stroke, at least in part, independently from age, lifestyle, and other cardiovascular risk factors.

Race- and sex-specific associations of obesity measures with ischemic stroke incidence in the Atherosclerosis Risk in Communities (ARIC) study

BACKGROUND AND PURPOSE

Studies have suggested differences in the association between obesity and ischemic stroke in black versus white populations. In this study, we explored ischemic stroke risk in relation to a variety of obesity measures by sex and race.

METHODS

Using data from the Atherosclerosis Risk in Communities Study, we obtained information on body mass index, waist circumference, and waist-to-hip ratio from 13 549 black and white participants who were aged 45 to 65 years between 1987 and 1989. All were free of cardiovascular disease and cancer at baseline. Incident strokes over a median follow-up of 16.9 years were ascertained from hospital records.

RESULTS

Although crude incidence rates of ischemic stroke varied more than 3-fold by race and sex, the relationship between higher measures of obesity and ischemic stroke risk was positive and linear across all groups. The crude incidence of ischemic stroke was 1.2 per 1000 person-years for white women with the lowest body mass index, ranging up to 8.0 per 1000 person-years for black men with the highest body mass index. Hazard ratios for the highest versus lowest quintile of body mass index, waist circumference, and waist-to-hip ratio ranged from 1.43 to 3.19, indicating increased stroke risk associated with obesity, however it was measured, even after adjustment for potential confounders. Additional adjustment for factors that may mediate the relationship, such as diabetes and hypertension, significantly attenuated the associations, suggesting that these factors may explain much of the stroke risk associated with obesity.

CONCLUSIONS

Degree of obesity, defined by body mass index, waist circumference, or waist-to-hip ratio, was a significant risk factor for ischemic stroke regardless of sex or race.

Height, wealth, and health: an overview with new data from three longitudinal studies

This overview, based on a literature review and new data from the three cohorts (Whitehall Studies I and II, and the Vietnam Experience Study), has four objectives: (a) to outline the major determinants of height, so providing an indication as to what exposures this characteristic may capture; (b) to summarise, by reviewing reports from large scale studies, the relation between adult height and a range of disease outcomes--both somatic and psychiatric--with particular emphasis on coronary heart disease (CHD) and stroke; (c) to discuss why these relationships may exist, in particular, the role, if any, of socioeconomic position in explaining the apparent associations; and, finally (d) to outline future research directions in this field. The large majority of evidence for predictors of height, and its health consequences, comes from observational studies. While genetic predisposition is a major determinant of height, secular rises in childhood and adult stature across successive birth cohorts suggest that early life environment also has an important impact. Plausible non-genetic determinants of height include nutrition, illness, socioeconomic status, and psychosocial stress. Evidence for an association between height and a series of health endpoints is accumulating. Thus, shorter people appear to experience increased risk of CHD, and these associations appear to be independent of socioeconomic position and other potentially confounding variables. For stroke, and its sub-types, findings are less clear. In contrast to CHD, some cancers, such as carcinoma of the colorectum, prostate, breast (in women), central nervous system, skin, endometrium, thyroid and blood (haematopoietic) are more common in taller people. While height may be negatively related to the risk of completed suicide, conclusions about the links between stature and other health endpoints is problematic given the paucity of evidence, which should be addressed. Ultimately, for want of better data, investigators in this area have used height as a proxy for a range of pre-adult exposures. In future, research should aim to explore the predictive capacity of direct measures of diet, psychosocial stress, childhood chronic illness and so on, rather than focus on height or its components. The problem is that extended follow-up of child cohorts with such data are required, and studies which hold these data are not currently available, although several are either maturing to the point where they offer sufficient clinical outcomes to facilitate analyses or are in the advanced planning stage.

Prevalence of metabolic syndrome and its association with obesity indices in a Chinese population

BACKGROUND

To investigate the prevalence of metabolic syndrome in an urbanizing community in Qingpu, a suburb of Shanghai, and to determine which obesity indices, including body mass index, waist circumference (WC), and waist:hip (WHpR), and waist:height (WHtR) ratios, are most closely associated with metabolic syndrome.

METHODS

We conducted a cross-sectional health survey of 1634 individuals (age 15-87 years) in the Jinhulu community located in Qingpu. The National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (NCEP ATP III) criteria were used to define metabolic syndrome, with central obesity defined according to Asia-Pacific (APC) region criteria.

RESULTS

The age-standardized prevalence of metabolic syndrome was 3.6% in men and 7.2% in women. Using the criterion of central obesity in the APC, the age-standardized prevalence of metabolic syndrome increased to 8.3% in men and 10.9% in women. Regardless of age, WHtR consistently showed a higher odd ratios (OR) after adjustment for confounding factors of 2.17 (95% confidence interval [CI] 1.12-4.20; P = 0.022) in subjects<52 years of age and 1.92 (95% CI 1.18-3.11; P = 0.008) in those ≥52 years of age. In men, the WHtR was the only significant predictor (OR 2.42; 95% CI 1.15-5.08; P = 0.02) of metabolic syndrome after adjustment, whereas in women WHtR (OR 1.87; 95% CI 1.37-2.85; P =0.0088) was slightly inferior to WHpR and WC.

CONCLUSION

Metabolic syndrome is prevalent in an urbanizing rural area in Qingpu. Of the anthropometric parameters commonly used to identify metabolic syndrome, WHtR may be the best.

General and abdominal adiposity and risk of stroke in Chinese women

BACKGROUND AND PURPOSE

Although both general and abdominal adiposity are well-established risk factors for coronary heart disease, their associations with stroke are less well characterized, particularly in generally lean Asian populations.

METHODS

We evaluated associations of body mass index (BMI), waist-hip ratio (WHR), waist circumference (WC), and waist-height ratio (WHtR) with stroke risk in the Shanghai Women's Health Study, a population-based prospective cohort study of 74 942 Chinese women aged 40 to 70 years with anthropometric measurement taken at recruitment in 1996 to 2000. For this analysis, we included 67 083 women with no prior history of stroke, coronary heart disease, rheumatic heart disease, cardiac surgery, or cancer at recruitment. Incident stroke was ascertained by biennial home visits and linkage with vital statistics registries.

RESULTS

Cut points for the highest quintiles of BMI, WHR, WC, and WHtR among this cohort were 26.6 (kg/m(2)), 0.85 (cm/cm), 84.1 (cm), and 0.54 (cm/cm), respectively. During a mean follow-up of 7.3 years, 2403 incident stroke cases were identified. All selected anthropometric measurements were positively and significantly associated with risk of total, ischemic, and hemorrhagic stroke in a dose-response manner (all probability values for trend <0.01). The multivariable-adjusted hazard ratios (95% confidence intervals) for total stroke comparing the highest versus lowest quintiles of these measurements were 1.71 (1.49 to 1.97), 1.59 (1.37 to 1.85), 1.77 (1.53 to 2.05), and 1.91 (1.61 to 2.27) for BMI, WHR, WC, and WHtR, respectively.

CONCLUSIONS

Increasing levels of general or abdominal adiposity consistently predict increased risk of stroke in predominantly nonobese Chinese women.

Waist to height ratio is a simple and effective obesity screening tool for cardiovascular risk factors: Analysis of data from the British National Diet And Nutrition Survey of adults aged 19-64 years

OBJECTIVE AND METHOD

To analyse data from the nationally representative National Diet and Nutrition Survey (NDNS) collected in 2000/2001 and to investigate how the BMI and two proxy indicators of central fat distribution, namely the waist circumference and the waist to height ratio (WHtR), are associated with each other and with cardiovascular disease (CVD) risk factors.

RESULTS

Screening health risk by BMI alone would 'miss' 35% of men and 14% of women who are within the normal BMI range (18.5-25 kg/m(2)) but have central fat distribution, defined by WHtR > 0.5. In the total population this equates to 17% of all men and 6% of all women who would be inadequately screened by BMI alone. Compared to BMI, WHtR was more closely associated with CVD risk factors among both men and women. Furthermore, in a combined analysis of men and women, central fat distribution with a normal BMI was associated with higher levels of CVD risk factors than being overweight without central fat distribution.

CONCLUSION

WHtR is a simple and effective, non-invasive screening tool for CVD risk factors. Our proposed boundary value of 0.5 translates into a simple public health message: 'Keep your waist circumference to less than half your height'.

Contribution of Obesity and Abdominal Fat Mass to Risk of Stroke and Transient Ischemic Attacks

Background and Purpose— Waist circumference has been shown to be a better predictor of cardiovascular risk than body mass index (BMI). Our case-control study aimed to evaluate the contribution of obesity and abdominal fat mass to the risk of stroke and transient ischemic attacks (TIA).

Methods— We recruited 1137 participants: 379 cases with stroke/TIA and 758 regional controls matched for age and sex. Associations between different markers of obesity (BMI, waist-to-hip ratio, waist circumference and waist-to-stature ratio) and risk of stroke/TIA were assessed by using conditional logistic regression adjusted for other risk factors.

Results— BMI showed a positive association with cerebrovascular risk which became nonsignificant after adjustment for physical inactivity, smoking, hypertension, and diabetes (odds ratio 1.18; 95% CI, 0.77 to 1.79, top tertile versus bottom tertile). Markers of abdominal adiposity were strongly associated with the risk of stroke/TIA. For the waist-to-hip ratio, adjusted odds ratios for every successive tertile were greater than that of the previous one (2nd tertile: 2.78, 1.57 to 4.91; 3rd tertile: 7.69, 4.53 to 13.03). Significant associations with the risk of stroke/TIA were also found for waist circumference and waist-to-stature ratio (odds ratio 4.25, 2.65 to 6.84 and odds ratio 4.67, 2.82 to 7.73, top versus bottom tertile after risk adjustment, respectively).

Conclusions— Markers of abdominal adiposity showed a graded and significant association with risk of stroke/TIA, independent of other vascular risk factors. Waist circumference and related ratios can better predict cerebrovascular events than BMI.

Risk factors for ischaemic stroke

Stroke is a leading cause of morbidity and mortality in western populations, with up to 40% of survivors not expected to recover independence from severe disabilities. This equates to an immense financial burden on health systems worldwide. Hence further education is required to inform individuals of the risks to promote secondary prevention strategies in future generations. Stroke is a heterogeneous, multifactorial disease regulated by modifiable and nonmodifiable risk factors. Modifiable factors include a history of high blood pressure, diabetes mellitus and coronary heart disease. Nonmodifiable factors include age, sex and race. Other less-well documented risk factors include geographic location, socioeconomic status and alcoholism. Approximately 80% of stroke events could be reduced by making simple lifestyle modifications. Further studies are required to clarify the role and interplay of the risk factors outlined to give a more comprehensive understanding of stroke and to aid and drive the development of more effective stroke prevention programs, in high risk groups.

Primary prevention of stroke by healthy lifestyle

BACKGROUND

The combination of healthy lifestyle factors is associated with lower risk of coronary heart disease, diabetes, and total cardiovascular disease. Little is known about the impact of multiple lifestyle factors on the risk of stroke.

METHODS AND RESULTS

We conducted a prospective cohort study among 43,685 men from the Health Professionals Follow-up Study and 71,243 women from the Nurses' Health Study. Diet and other lifestyle factors were updated from self-reported questionnaires. We defined a low-risk lifestyle as not smoking, a body mass index <25 kg/m(2), >or=30 min/d of moderate activity, modest alcohol consumption (men, 5 to 30 g/d; women, 5 to 15 g/d), and scoring within the top 40% of a healthy diet score. We documented 1559 strokes (853 ischemic, 278 hemorrhagic) among women and 994 strokes (600 ischemic, 161 hemorrhagic) among men during follow-up. Women with all 5 low-risk factors had a relative risk of 0.21 (95% confidence interval [CI], 0.12, 0.36) for total and 0.19 (95% CI, 0.09, 0.40) for ischemic stroke compared with women who had none of these factors. Among men, the relative risks were 0.31 (95% CI, 0.19, 0.53) for total and 0.20 (95% CI, 0.10, 0.42) for ischemic stroke for the same comparison. Among the women, 47% (95% CI, 18 to 69) of total and 54% (95% CI, 15 to 78%) of ischemic stroke cases were attributable to lack of adherence to a low-risk lifestyle; among the men, 35% (95% CI, 7 to 58) of total and 52% (95% CI, 19 to 75) of ischemic stroke may have been prevented.

CONCLUSIONS

A low-risk lifestyle that is associated with a reduced risk of multiple chronic diseases also may be beneficial in the prevention of stroke, especially ischemic stroke.