Relationship between visceral fat accumulation and hypertension in obese men

Association of Anthropometric Indices of Obesity with Hypertension in Chinese Elderly: An Analysis of Age and Gender Differences

This study aims to explore the association of anthropometric indices of obesity with hypertension in Chinese elderly and its possible gender and age differences. A total of 7070 adults age 60 or older were interviewed in a cross-sectional study conducted in 2017. Anthropometric indices for each participant were measured by using standard methods of trained doctoral/master students. We performed two binary logistic regression models to examine the association of the nine different anthropometric indices and hypertension by gender. Lastly, analyses were performed in two steps stratified for age. Comparing individuals with and without hypertension, there were statistically significant differences in anthropometric indices except height, a body shape index (ABSI), and hip index (HI) in males; and except height in females. There were gender differences in the relationship between anthropometric indices and the prevalence of hypertension in Chinese older adults. After stratification by age, the associations of all anthropometric indices became weaker, disappeared, or even went in the opposite direction. Furthermore, body mass index (BMI) in men (except individuals older than 80) and hip circumference (HC) in women showed a significant impact on the risk of hypertension. The association of anthropometric indices of obesity with hypertension in Chinese elderly differ by gender and age. These findings indicate a need to develop gender-specific strategies for the male and female elderly in the primary and secondary prevention of hypertension.

Elucidating the role of adipose tissue secreted factors in malignant transformation

Although there is a growing number of incidences of obesity and obesity-linked cancers, how excess adiposity actually causes cancer has not been fully explained. Our previous study showed that removal of visceral adipose tissue significantly reduced the number of ultraviolet radiation (UVR)-initiated, high-fat diet-promoted skin cancers. This commentary focuses on our recently published study (Chakraborty, et al., 2017) which demonstrated that fibroblast growth factor-2 (FGF2) released from visceral adipose tissue is a key factor in the malignant transformation of epithelial cells. Within this commentary we have provided additional interpretations and new data in support of the role of FGF2 in adiposity-associated tumorigenesis.

Role of Obesity Variables in Detecting Hypertension in an Iranian Population

INTRODUCTION

As the high incidence of hypertension has been in conjunction with dramatic increase in the prevalence of obesity, many studies have suggested obesity as its underlying cause in diverse race and ethnic groups.

AIM

The present study was designed to quantify the relationship between obesity variables and hypertension in Iranian population. A ROC curve analysis was also used to determine an optimal BMI cutoff for obesity with the aim of representing elevated incidence of hypertension in this population.

METHODS

The study population comprised of apparently healthy men and women who participated in the Iranian Multi-centric Osteoporosis Studies (IMOS), a multi-centric cross-sectional study carried out in urban areas of five great cities (Tehran, Tabriz, Mashhad, Shiraz and Bushehr). The anthropometric (weight, height, waist and hip circumferences) and blood pressure measures were reported in some 5724 subjects. The influence of these factors on systolic and diastolic blood pressure was assessed based on a list-wise method.

RESULTS

There was a significant difference in the studied subjects anthropometric (weight classes (BMI), WC and HC, and WHR) and blood pressure variables; age, gender and weight, however, were the only factors significantly influencing SBP and DBP. Furthermore, BMI showed a significant impact on the overall risk of developing hypertension.

CONCLUSION

General obesity rather than abdominal obesity is directly linked with higher blood pressure levels in Iranian population.

Effects of sex and site on amino acid metabolism enzyme gene expression and activity in rat white adipose tissue

Background and Objectives. White adipose tissue (WAT) shows marked sex- and diet-dependent differences. However, our metabolic knowledge of WAT, especially on amino acid metabolism, is considerably limited. In the present study, we compared the influence of sex on the amino acid metabolism profile of the four main WAT sites, focused on the paths related to ammonium handling and the urea cycle, as a way to estimate the extent of WAT implication on body amino-nitrogen metabolism. Experimental Design. Adult female and male rats were maintained, undisturbed, under standard conditions for one month. After killing them under isoflurane anesthesia. WAT sites were dissected and weighed. Subcutaneous, perigonadal, retroperitoneal and mesenteric WAT were analyzed for amino acid metabolism gene expression and enzyme activities. Results. There was a considerable stability of the urea cycle activities and expressions, irrespective of sex, and with only limited influence of site. Urea cycle was more resilient to change than other site-specialized metabolic pathways. The control of WAT urea cycle was probably related to the provision of arginine/citrulline, as deduced from the enzyme activity profiles. These data support a generalized role of WAT in overall amino-N handling. In contrast, sex markedly affected WAT ammonium-centered amino acid metabolism in a site-related way, with relatively higher emphasis in males' subcutaneous WAT. Conclusions. We found that WAT has an active amino acid metabolism. Its gene expressions were lower than those of glucose-lipid interactions, but the differences were quantitatively less important than usually reported. The effects of sex on urea cycle enzymes expression and activity were limited, in contrast with the wider variations observed in other metabolic pathways. The results agree with a centralized control of urea cycle operation affecting the adipose organ as a whole.

A comparison of body mass index and waist-to-hip ratio as indicators of hypertension risk in an urban Argentine population: a hospital-based study

BACKGROUND AND AIM

To examine the relationship between 24-h ambulatory blood pressure monitoring (ABPM) and three commonest anthropometric measurements for obesity [body mass index (BMI), waist circumference (WC) and waist-hip ratio (WHR)] in patients with essential hypertension never treated or after a 3 week placebo period, living in Buenos Aires.

METHODS AND RESULTS

Cross-sectional survey among outpatients at the Hypertension Program of Buenos Aires University Hospital de Clinicas. Three-hundred seventy-seven essential hypertensives, aged 18-86 years, of either sex, were consecutively recruited. All subjects underwent 24 h ABPM performed with a blood pressure (BP) device. The prevalence of overweight-obesity was 56.76% in women and 75.86% in men. High WHR prevalence in non-obese women was 4.5% and 4.1% in non-obese men while high values of WC were observed in 3.0% of non-obese women and in 0% of non-obese men. The two-way ANCOVA showed that in women with high values of WHR, 24 h DBP was higher in those with BMI<25 than in those with BMI> or =25. Those females with a BMI> or =25 had a higher prevalence of top tertile values of PP (> or =68 mmHg) (P<0.05) than non-obese females. Only in women was mean pulse pressure (PP) significantly correlated with age (r=0.38; P<0.0001), WC (r=0.22; P<0.005), WHR (r=0.21, P<0.008), and BMI (r=0.20; P<0.01) while in men there was no significant correlation between variables. Logistic regression showed that the odds of morning blood pressure surge (MBPS) increased with age, central obesity (represented by high WHR and dipper status), while the odds of higher mean PP increased with age and high WHR.

CONCLUSION

These results indicated a high prevalence of overweight-obesity (more than 56% of women and 75% of men) in our hospital-based sample of essential hypertension and that the WHR offers additional information beyond BMI and WC to predict the hypertension risk according to the ABPM.

Racial/ethnic differences in prehypertension in American adults: Population and relative attributable risks of abdominal obesity

To estimate the risk and population attributable risk of prehypertension that is due to abdominal obesity in White, Black and Hispanic American adults. To determine how much of the relative difference in the risk of prehypertension between high-risk Blacks and Hispanics and the low-risk group Whites that is attributable to their differences in abdominal obesity. Data (n=4016) from the 1999 to 2000 US National Health and Nutrition Examination Surveys were used in this study. Abdominal obesity was defined as waist circumference >/=102 and >/=88 cm in men and women, respectively. Prehypertension was defined as not being on antihypertensive medication and having systolic blood pressure of 120-139 mmHg or diastolic blood pressure of 80-89 mmHg. Odds ratio from the logistic regression analysis was used to estimate the risk of prehypertension that was due to abdominal obesity. To estimate prehypertension risk differences between low-risk Whites and high-risk Blacks and Hispanics that was due to abdominal obesity, we estimated relative attributable risk. Statistical adjustments were made for age, blood glucose, total cholesterol, current smoking and exercise. Abdominal obesity was associated with increased odds of prehypertension in Whites, Blacks and Hispanics. In men, abdominal obesity was associated with 44, 90 and 98% increased odds of prehypertension in Whites, Blacks and Hispanics, respectively. The corresponding values in women were 112, 198 and 104%. Proportions of risk of prehypertension explained by abdominal obesity were 15.2, 22 and 25.8% in White men, Black men and Hispanic men, respectively. The corresponding values in women were 38.8, 58.6 and 32.5%. Approximately, 7% of the differences in the risk of developing prehypertension between White and Black men and between White and Hispanic men may be attributable to differences in rates of abdominal obesity. The analogous values for women were approximately 39.7 and approximately 16.5%, respectively. In conclusion, despite having lower rates of abdominal obesity than their counterparts, Black men, Hispanic men and Hispanic women had high population attributable risks, indicating that factors other than abdominal obesity may have important explanatory power for racial differences in prehypertension in these groups. However, in Black women reduction in risk of prehypertension could be possible by instituting public health measures to reduce abdominal obesity to the levels seen in White women. Intervention programmes designed to reduce overall obesity may also lead to reduction of abdominal obesity, and consequently may curb prehypertension in these population groups. Life-style modification, including diet and exercise, may have public health significance in reducing the incidence of prehypertension in these populations.