The relationship between blood pressure and left ventricular mass index depends on an excess adiposity

Obesity and Body Mass Components Influence Exercise Tolerance and the Course of Hypertension in Perimenopausal Women

The aim of this study was to identify the potential influence of obesity and body mass components on exercise tolerance assessed in cardiopulmonary exercise testing (CPET), biochemical and echocardiographic parameters and factors correlated with oxygen absorption at the anaerobic threshold in hypertensive women with low levels of physical activity in the perimenopausal period. The study comprised 188 hypertensive women divided, based on body mass index (BMI), into an obesity group and a non-obesity group. Women with BMI ≥ 30 kg/m2 had significantly higher parameters of left ventricular diastolic dysfunction in echocardiography, lower total body water (TBC) in percentage assessed by bioimpedance and significantly worse exercise capacity assessed by CPET. In the study group, VO2 AT (mL/kg/min) correlated positively with TBW (r = 0.4, p < 0.0001) and with the ratio of extracellular water to total body water (ECW/TBW) (r = 0.4, p < 0.00001) and negatively with fat (% and kg) (r = −0.4, p < 0.0001 for both). Obesity negatively affects parameters of diastolic left ventricular function, as well as exercise tolerance in CPET in hypertensive females during the perimenopausal period. The oxygen uptake at anaerobic threshold correlates positively with total body water and ECW/TBW and negatively with body fat; this connection is more pronounced in women without obesity. ClinicalTrials.gov Identifier: NCT04802369.

THE ROLE OF LEPTINRESISTANCE IN THE PATHOGENESIS OF OBESITY IN PREGNANT WOMEN

OBJECTIVE

The aim: To investigate the relationship between leptin resistance, lipid and carbohydrate metabolism, blood pressure in obese pregnant women.

PATIENTS AND METHODS

Materials and methods: Under observation were 65 women (main group) with obesity (I degree -27 women, II degree - 24 women, III degree - 14 women) in the II trimester of pregnancy, who were hospitalized in the Department of Pathology of Pregnancy KNP «Maternity Clinical house №1 "in Lviv during 2017-2020 on preeclampsia of varying severity, which were sent for inpatient treatment by women's clinics. The control group consisted of 30 healthy pregnant women without obesity.

RESULTS

Results: Serum leptin in obese women was directly correlated with BMI (r = 0.66, p<0.001), body weight (r = 0.29, p<0.05), total cholesterol (cholesterol) (r = 0, 37, p<0,009), low density lipoproteins (LDL cholesterol) (r = 0.33, p<0.05) and inversely with high density particles (HDL cholesterol) (r = -0.37, p<0.02 ). Studies of carbohydrate metabolism indicate the following correlation coefficients of BMI with glucose level r = 0.351; p<0,001, BMI with the level of C-peptide r = 0,450; p<0,001, BMI with HOMA index r = 0,1504; p = 0.036. Inverse correlations of C-peptide were detected with the level of P (r = -0.169; p = 0.025).

CONCLUSION

Conclusions: The discovery of the relationship between leptin resistance, lipid and carbohydrate metabolism, blood pressure indicates the possibility of using signs of leptin resistance to prevent complications during pregnancy in the second trimester.

Prevalence and Risk Factors of Left Ventricular Diastolic Dysfunction in Patients With Hyperthyroidism

BACKGROUND

Left ventricular (LV) diastolic dysfunction has been demonstrated to be an independent predictor of the future heart failure. Heart failure is one of the severe complications caused by overt hyperthyroidism. However, the effects of overt hyperthyroidism on diastolic dysfunction are conflicting, and little is known about the prevalence and risk factors of the diastolic dysfunction in patients with overt hyperthyroidism.

METHODS

A total of 388 patients with overt hyperthyroidism were included and compared with 388 age- and gender- matched euthyroid control subjects. LV diastolic function was evaluated by traditional and tissue-Doppler echocardiography. Routine clinical medical data and echocardiographic parameters were recorded for analysis.

RESULTS

The prevalence of LV diastolic dysfunction was 35.1% among hyperthyroid patients and significantly higher than control subjects whose prevalence was 25.5% (P = 0.003), and it increased with age and body mass index (BMI) in patients with overt hyperthyroidism. The possible risk factors for LV diastolic dysfunction, such as hypertension, diabetes, decreased estimated glomerular filtration rate (eGFR), and increased level of thyroid hormones weren't associated with LV diastolic dysfunction. However, overweight or obese were significantly associated with LV diastolic dysfunction (OR = 3.024, 95% CI = 1.517-6.027, P = 0.002) compared with normal BMI. When compared with age <40 years old group, 40-50 years old group, 50-60 years old group and age ≥60 years old group were significantly associated with LV diastolic dysfunction, with ORs of 2.976 (95% CI = 1.744-5.019), 12.424 (95% CI = 4.934-31.283), 24.966 (95% CI = 5.975-104.321), respectively.

CONCLUSION

LV diastolic dysfunction was very common, in particular, in older and overweight or obese patients with overt hyperthyroidism. Additionally, age and BMI were independent risk factors for LV diastolic dysfunction, while the level of thyroid hormones was not. Therefore, besides the LV systolic function, we also need focus on the diastolic function in patients with overt hyperthyroidism in clinical work, especially the older and overweight or obese patients.

Central Blood Pressure Parameters Correlate with Cardiac Structure and Function in Healthy Chinese Individuals without Cardiovascular Disease

PURPOSE

To explore the relationship between central blood pressure (BP) parameters and cardiac structure and function parameters in healthy individuals.

METHODS

Four hundred Chinese participants with no overt cardiovascular disease participated in this study. One hundred and seventy-one participants (42.8%) were male and the mean age was 60 years. Central BP was measured with the SphygmoCor system. Cardiac structure and function were assessed by echocardiography.

RESULTS

We showed a significant association of left atrial volume and left ventricular mass index (LVMI) with brachial and central systolic BP (SBP) and pulse pressure (PP; r = 0.189-0.0.39, p < 0.001). Left ventricular diastolic function and the E/A ratio were significantly associated with brachial and central BP (r = 0.228-0.469, p < 0.001). Multivariate regression analysis revealed that central SBP and PP were independently correlated with LVMI after normalization for age and other confounding variables (sex, body mass index, smoking, and alcohol intake, and the levels of triglycerides, high-density lipoprotein, low-density lipoprotein, creatinine, uric acid, fasting blood glucose, log C-reactive protein, and fibrinogen. However, only central SBP was found to be independently correlated with the E/A ratio.

CONCLUSIONS

Cardiac structure and diastolic function were associated with brachial and central BP. However, after normalization, cardiac structure parameters were independently correlated with central SBP and PP. Diastolic function was the only cardiac function parameter that correlated with central SBP.

Abdominal Obesity Is Associated With an Increased Risk of All-Cause Mortality in Patients With HFpEF

BACKGROUND

There is a lack of studies that evaluate the association between abdominal obesity and subsequent outcomes in patients with heart failure with preserved ejection fraction (HFpEF).

OBJECTIVES

The present study aimed to assess the association between abdominal obesity and risk of all-cause mortality in patients with HFpEF.

METHODS

The present study used data from the TOPCAT (Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist) trial. The primary outcome was all-cause mortality. We analyzed and compared the hazard ratios (HRs) in patients with abdominal obesity and those without abdominal obesity using multivariable Cox proportional hazard models. Abdominal obesity was defined as a waist circumference of ≥102 cm in men and ≥88 cm in women.

RESULTS

The present study included 3,310 patients with HFpEF: 2,413 patients with abdominal obesity and 897 without abdominal obesity. The mean follow-up was 3.4 ± 1.7 years. During follow-up, 500 patients died. All-cause mortality rates in patients with and without abdominal obesity were 46.1 and 40.7 events per 1,000 person-years, respectively. After multivariable adjustment, the risk of all-cause mortality was significantly higher in patients with abdominal obesity than in those without abdominal obesity (adjusted HR: 1.52; 95% confidence interval [CI]: 1.16 to 1.99; p = 0.002). The risk of cardiovascular and noncardiovascular mortality was also significantly higher in patients with abdominal obesity than in those without abdominal obesity (adjusted HR: 1.50; 95% CI: 1.08 to 2.08; p = 0.01 and adjusted HR: 1.58; 95% CI: 1.00 to 2.51; p = 0.04, respectively).

CONCLUSIONS

The risk of all-cause mortality was significantly higher in patients with HFpEF with abdominal obesity than in those without abdominal obesity.

Association of Blood Pressure Variability Ratio With Glomerular Filtration Rate Independent of Blood Pressure and Pulse Wave Velocity

BACKGROUND

Blood pressure variability ratio (BPVR)(derived from within-subject SD of 24-hour ambulatory blood pressure [BP]) predicts all-cause mortality independent of BP and has a similar prognostic ability to ambulatory arterial stiffness (AASI). Whether BPVR, and AASI, offer prognostic information beyond measurements of arterial stiffness at a given pressure, as indexed by pulse wave velocity (PWV), is not known.

METHODS

We assessed whether BPVR and AASI were associated with indices of subclinical organ damage (TOD) [estimated glomerular filtration rate (eGFR), left ventricular mass index, early-to-late transmitral velocity (E/A), carotid intima-media thickness (IMT)] independent of BP, and whether BPVR-TOD and AASI-TOD relations were independent of PWV (applanation tonometry) in 772 randomly selected participants from an urban, developing community. AASI was derived from 24-hour diastolic BP vs. systolic BP standard linear regression.

RESULTS

On bivariate analyses, BPVR, AASI, and PWV were correlated with all indices of TOD (P < 0.0005). However, after adjustments for potential confounders including age and 24-hour mean BP, BPVR, and PWV (P < 0.005 to P < 0.0001), but not AASI (P > 0.25), were independently associated with eGFR, but not other indices of TOD. Importantly, the BPVR-eGFR relation was independent of BP variability (P < 0.005) and PWV (P < 0.001).

CONCLUSIONS

BPVR was negatively associated with eGFR independent of mean BP, BP variability, and PWV. Therefore, in the prediction of cardiovascular risk, measurements of arterial stiffening (BPVR) may provide information beyond the impact of arterial stiffness.

Relationship between body fat percentage determined by bioelectrical impedance analysis and metabolic risk factors in Syrian male adolescents (18–19 years)

The association between increasing obesity and metabolic syndrome among adolescent and the adverse consequences in adulthood including type-2 diabetes and coronary heart disease is well documented. The main objectives of this study were to evaluate the major metabolic risk factors and some clinical important parameters in Syrian male adolescents (18–19 years old), and to assess the correlations between BF% determined by BIA-man prediction equation and metabolic risk factors in the same group. The correlations between body fat percentage (BF%) based on BIA-man predictive equations, blood pressure, fasting blood sugar (FBS), cholesterol (Chol), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), triglycerides (TG), Hematocrit (Ht), and hemoglobin (Hb) in 1596 healthy Syrian adolescents aged 18-19 years and the mean values of these parameters were examined. Data showed that, DBP, Chol, TG, LDL and TG/HDL-C were significantly (p<0.05) higher in overweight and obese subjects in compression to normal weight cases. Whereas, SBP, FBS and Ht were significantly (p<0.05) higher in obese subjects in compression to normal weight. However, all measured variable related to metabolic syndrome risk factors increased with increasing the BF% determined by BIA-man. The present study suggests that % BF by BIA-man is a good predictor of metabolic risks factors for Syrian adolescents.

The innovative "Bio-Oil Spread" prevents metabolic disorders and mediates preconditioning-like cardioprotection in rats

BACKGROUND AND AIMS

Obesity is often associated with an increased cardiovascular risk. The food industry and the associated research activities focus on formulating products that are a perfect mix between an adequate fat content and health. We evaluated whether a diet enriched with Bio-Oil Spread (SD), an olive oil-based innovative food, is cardioprotective in the presence of high-fat diet (HFD)-dependent obesity.

METHODS AND RESULTS

Rats were fed for 16 weeks with normolipidic diet (ND; fat: 6.2%), HFD (fat: 42%), and ND enriched with SD (6.2% of fat + 35.8% of SD). Metabolic and anthropometric parameters were measured. Heart and liver structures were analyzed by histochemical examination. Ischemic susceptibility was evaluated on isolated and Langendorff-perfused cardiac preparations. Signaling was assessed by Western blotting. Compared to ND rats, HFD rats showed increased body weight and abdominal obesity, dyslipidemia, and impaired glucose tolerance. Morphological analyses showed that HFD is associated with heart and liver modifications (hypertrophy and steatosis, respectively), lesser evident in the SD group, together with metabolic and anthropometric alterations. In particular, IGF-1R immunodetection revealed a reduction of hypertrophy in SD heart sections. Notably, SD diet significantly reduced myocardial susceptibility against ischemia/reperfusion (I/R) with respect to HFD through the activation of survival signals (Akt, ERK1/2, and Bcl2). Systolic and diastolic performance was preserved in the SD group.

CONCLUSIONS

We suggest that SD may contribute to the prevention of metabolic disorders and cardiovascular alterations typical of severe obesity induced by an HFD, including the increased ischemic susceptibility of the myocardium. Our results pave the way to evaluate the introduction of SD in human alimentary guidelines as a strategy to reduce saturated fat intake.

The Role of Obesity in the Development of Left Ventricular Hypertrophy Among Children and Adolescents

Both obesity and hypertension have increased substantially among children over the last several decades. At the same time, mounting evidence has pointed to the role of these and other cardiovascular disease risk factors on the development of end organ damage such as left ventricular hypertrophy in children. While traditionally thought to occur in response to an increased afterload as in systemic hypertension, evidence demonstrates that obesity is associated with left ventricular hypertrophy independent of blood pressure. Both hemodynamic and non-hemodynamic factors contribute to the pathogenesis of obesity-related left ventricular remodeling. However, more contemporary research suggests that adiposity and blood pressure have a greater effect on left ventricular geometry when present together than when present alone. Normalization of left ventricular mass in obese hypertensive individuals requires achievement of both normotension and weight loss. Additional strategies are needed to promote the cardiovascular health of children, with greater emphasis placed on obesity prevention.

Do Obese Individuals With Hypertension Have More Difficult-to-Control Blood Pressure and End Organ Damage Than Their Nonobese Counterparts?

The authors assessed whether individuals with elevated body mass index (BMI) and hypertension had more difficult-to-control blood pressure (BP) and more evidence of end organ damage using data collected prospectively over 11 years from a secondary care hypertension clinic. A total of 1114 individuals were divided by BMI criteria into normal (n=207), overweight (n=440), and obese (n=467). Mean daytime, nighttime, and 24-hour systolic BP and diastolic BP were similar in all groups. There was less nocturnal dip in obese compared with overweight groups (P=.025). Individuals with a normal BMI were taking fewer antihypertensive medications than those in the obese group (P=.01). Individuals classified as obese had a higher left ventricular mass index than those with a normal BMI (female, P=.028; male, P<.001); this relationship remained after multivariate linear regression. Obese individuals with hypertension required more medication to achieve similar mean ambulatory BP values, had less nocturnal dip in BP, and had a higher prevalence of left ventricular hypertrophy. As such, obese patients are at potentially increased risk of cardiovascular events.

Blood pressure profile in school children (6-16 years) of southern India: a prospective observational study

AIMS AND OBJECTIVE

To determine normal blood pressure (BP) in apparently healthy, asymptomatic school children in the age group of 6-16 years and to determine the correlation of BP values with different sex, weight, height, and body mass index (BMI) and also to find out prevalence of hypertension in school going population.

MATERIALS AND METHODS

This prospective, observational study enrolled 3,302 urban children (1,658 boys and 1,644 girls) in the age group of 6-16 years. These were analyzed to study the distribution pattern of systolic blood pressure (SBP) and diastolic blood pressure (DBP) at different ages, sex, weight, height, and BMI. The SBP and DBP were noted as per age and sex. The association was seen between mean SBP and mean DBP with weight, height, and BMI. Information was collected about the family history of hypertension and was correlated with the obtained SBP and DBP readings.

RESULTS

The mean SBP in males at 6 years was 99.69 ± 3.62 mm of Hg, at 10 years was 102.20 ± 2.16 mm of Hg, and at 16 years was 115.33 ± 1.26 mm of Hg. The mean SBP in females at 6 years was 96.55 ± 2.86 mm of Hg, at 10 years was 101.16 ± 2.12 mm of Hg, and at 16 years was 112.41 ± 1.06 mm of Hg. The correlation coefficient for relationship between age and SBP in males and females was 0.89 and 0.91, respectively, and for DBP was 0.92 and 0.90, respectively. The correlation coefficient for relationship between height and SBP in males and females was 0.91 and 0.93, respectively, and for DBP was 0.92 and 0.88, respectively. The correlation coefficient for relationship between weight and SBP in males and females was 0.92 and 0.92, respectively, and for DBP was 0.94 and 0.91, respectively. In the nomogram obtained in the study, 95% of study population fall between mean +2SD and -2SD.

CONCLUSION

The blood pressure (BP) (SBP and DBP) tends to increase with age, weight, height, and BMI. The BP values (SBP and DBP) increases grossly after 11 years of age. The students with positive family history of hypertension had higher valve when compared to other student. The BP of children and adolescents can be evaluated using the reference table according to age. The table provided helps to classify as "normal" or "hypertension" (>+2SD).

A longitudinal retrospective analysis of left ventricular mass in a cohort of pediatric kidney transplant recipients

Childhood end-stage kidney disease is associated with increased risk for early adulthood cardiovascular (CV) morbidity and mortality. Increased LVM is an early indicator of CV disease. Previous studies have suggested that LVM decreases after kidney transplantation; however, trends have been inconsistent. A single center retrospective longitudinal cohort analysis of LVM, documented annually, starting before kidney transplantation for up to 10 yr after transplantation was performed. BP documented by annual 24-h ambulatory monitoring studies, and BMI values were also reviewed. Twenty-seven children followed for a mean period of 5.3 yr were included. Depending on definition of LVH, its prevalence pretransplant and in the first years post-transplant was up to 33% dropping to 0-25% thereafter. Individual longitudinal LVM z-score trends were highly variable but generally trended toward the mean immediately after transplant and toward negative values in the following years. BP was stable during the follow-up period while mean annual BMI increased in the first-year post-transplant but declined thereafter. In a cohort of pediatric renal transplant recipients, prevalence of LVH decreased after transplant; however, individual longitudinal LVM trends were highly variable among patients. Prospective studies are needed to correlate individual LVM trends with outcomes.

Impact of general and central adiposity on ventricular-arterial aging in women and men

OBJECTIVES

The aim of this study was to assess the effects of central and general obesity measures on long-term longitudinal changes in ventricular-arterial mechanics.

BACKGROUND

Obesity, female sex, and ventricular-arterial stiffening are associated with the development of heart failure with preserved ejection fraction. Fat distribution and chronic changes in body composition may affect longitudinal changes in LV properties, independent of arterial load.

METHODS

In 1,402 subjects from a randomly selected, community-based population, comprehensive echo-Doppler echocardiography was performed at two examinations separated by 4 years. From this population, 788 subjects had paired data adequate for determining left ventricular end-systolic elastance (Ees), end-diastolic elastance (Eed), and effective arterial elastance (Ea).

RESULTS

Over 4 years, Ea was decreased by 3% in tandem with improved blood pressure control, whereas Ees and Eed were increased by 14% and 8% (all, p < 0.001). Greater weight loss over 4 years was associated with progressively greater decreases in Ea in men and women. After adjustment for Ea change, weight gain was correlated with increases in Eed in both women and men. Central obesity was associated with greater age-related increases in Ees in women but not in men, independent of arterial load, but central obesity did not predict changes in Eed or Ea.

CONCLUSIONS

In these subjects, weight gain was associated with increases in LV diastolic stiffness, even after adjustment for changes in arterial afterload, whereas weight loss was associated with reductions in arterial stiffness. Age-related LV systolic stiffening was increased in women, but not in men, with central obesity. Strategies for promoting weight loss and reducing central adiposity may be effective in preventing heart failure with preserved ejection fraction, particularly in women.

Gender specific pattern of left ventricular cardiac adaptation to hypertension and obesity in a tertiary health facility in Nigeria

BACKGROUND

Cardiac adaptation to hypertension and obesity may be related to many factors such as race, gender and haemodynamic status. Some gender specific associations with left ventricular structure and function have been described among Caucasians.

OBJECTIVES

To describe the sex specific pattern of left ventricular adaptations to obesity and hypertension among Nigerians.

METHODOLOGY

It was a cross sectional study carried out at LAUTECH Teaching Hospital, Osogbo, Nigeria. 313 subjects had full echocardiography performed. Participants were divided into four groups: normal, obese, hypertensives and obese-hypertensives. Indices of LV adaptation were compared between the groups. SPSS 16.0 was used for analysis.

RESULTS

Relative to normal subjects, LV mass (LVM), LV mass index (LVMI) and wall thickness were significantly higher among hypertensive men and obese hypertensive men. They were similar between normal and obese men. However, LVM, LVMI and wall thickness were increased among obese women compared to normal women while they were similar among obese, hypertensive and obese-hypertensive women. Men with concurrent obesity and hypertension presented with a further increase of LVM and wall thickness above values in the merely obese or hypertensive subjects. Female obese-hypertensive seem to present more with eccentric hypertrophy than male obese-hypertensive subjects (17.2% vs. 9.1% respectively, p<0.05) while male obese-hypertensive seem to present more with concentric hypertrophy (54.5% vs. 43.1% respectively, p>0.05) than female obese-hypertensive subjects.

CONCLUSION

Structural, functional and geometric LV adaptation to obesity and hypertension varies between the two genders among Nigerians. The impact of isolated obesity on LV adaptation in women appears very significant.

Relationships among HIV infection, metabolic risk factors, and left ventricular structure and function

Our objective was to determine if the presence of metabolic complications (MC) conveyed an additional risk for left ventricular (LV) dysfunction in people with HIV. HIV⁺ and HIV⁻ men and women were categorized into four groups: (1) HIV⁺ with MC (43±7 years, n=64), (2) HIV⁺ without MC (42±7 years, n=59), (3) HIV⁻ with MC (44±8 years, n=37), or (4) HIV⁻ controls without MC (42±8 years, n=41). All participants underwent two-dimensional (2-D), Doppler, and tissue Doppler echocardiography. Overall, the prevalence of systolic dysfunction (15 vs. 4%, p=0.02) and LV hypertrophy (9 vs. 1%, p=0.03) was greater in HIV⁺ than in HIV⁻ participants. Participants with MC had a greater prevalence of LV hypertrophy (10% vs. 1%). Early mitral annular velocity during diastole was significantly (p<0.005) lower in groups with MC (HIV⁺/MC⁺: 11.6±2.3, HIV⁻/MC⁺: 12.0±2.3 vs. HIV⁺/MC⁻: 12.4±2.3, HIV⁻/MC⁻: 13.1±2.4 cm/s) and tended to be lower in groups with HIV (p=0.10). However, there was no interaction effect of HIV and MC for any systolic or diastolic variable. Regardless of HIV status, participants with MC had reduced LV diastolic function. Although both the presence of MC and HIV infection were associated with lower diastolic function, there was no additive negative effect of HIV on diastolic function beyond the effect of MC. Also, HIV was independently associated with lower systolic function. Clinical monitoring of LV function in individuals with metabolic risk factors, regardless of HIV status, is warranted.

Myocardial structure, function and ischaemic tolerance in a rodent model of obesity with insulin resistance

Obesity and its comorbidities (dyslipidaemia, insulin resistance and hypertension) that together constitute the metabolic syndrome are all risk factors for ischaemic heart disease. Although obesity has been reported to be an independent risk factor for congestive heart failure, whether obesity-induced heart failure develops in the absence of increased afterload (induced by hypertension) is not clear. We have previously shown that obesity with insulin resistance decreases myocardial tolerance to ischaemia-reperfusion, but the mechanism for this decreased tolerance remains unclear. We hypothesize that obesity with insulin resistance induces adverse cardiac remodelling and pump dysfunction, as well as adverse changes in myocardial prosurvival reperfusion injury salvage kinase (RISK) pathway signalling to reduce myocardial tolerance to ischaemia-reperfusion. Wistar rats were fed an obesogenic (obese group) or a standard rat chow diet (control group) for 32 weeks. Echocardiography was performed over the 32 weeks before isolated Langendorff-perfused hearts were subjected to 40 min coronary artery ligation followed by reperfusion, and functional recovery (rate-pressure product), infarct size and RISK pathway function were assessed (Western blot analysis). Obesity with insulin resistance increased myocardial lipid accumulation but had no effect on in vivo or ex vivo left ventricular structure/function. Hearts from obese rats had lower reperfusion rate-pressure products (13115 ± 562 beats min(-1) mmHg for obese rats versus 17781 ± 1109 beats min(-1) mmHg for control rats, P < 0.05) and larger infarcts (36.3 ± 5.6% of area at risk in obese rats versus 14.1 ± 2.8% of area at risk in control rats, P < 0.01) compared with control hearts. These changes were associated with reductions in RISK pathway function, with 30-50 and 40-60% reductions in Akt and glycogen synthase kinase 3 beta (GSK-3β) expression and phosphorylation, respectively, in obese rat hearts compared with control hearts. Total endothelial nitric oxide synthase expression was reduced by 25% in obese rats. We conclude that obesity with insulin resistance had no effect on basal cardiac structure or function but decreased myocardial tolerance to ischaemia-reperfusion. This reduction in ischaemic tolerance was likely to be due to compromised RISK pathway function in obese, insulin-resistant animals.

Recent advances in hypertension in sub-Saharan Africa

BACKGROUND

Hypertension was once considered rare in sub-Saharan Africa (SSA), but currently it has become a widespread problem with immense socioeconomic importance. The purpose of this review is to summarise new information on hypertension in SSA that has been published since the last major review in 2008.

METHODS AND RESULTS

A literature search was performed in Pubmed, Embase, WHO Global Cardiovascular Infobase, African Journal On-Line, and African Index Medicus using the following search criteria: hypertension, high blood pressure, and Africa/SSA. Epidemiological surveys that used the WHO STEPS approach or similar methods were also included. The overall prevalence of hypertension in SSA was estimated at 16.2% (95% CI 14.2% to 20.3%) with an estimated number of hypertensive individuals to be 74.7 million. The prevalence of hypertension varies widely from country to country. It is projected that the number of affected individuals will increase by 68% (125.5 million) by 2025. Mass migration of rural Africans to urban areas and rapid changes in lifestyle and risk factors account for the rising prevalence of hypertension.

CONCLUSIONS

Proactive public health interventions at a population level need to be introduced to control the growing hypertension epidemic, and there needs to be a major improvement in access to hypertensive care for the individual. There is an important need for better epidemiological data and hypertension related outcome trials in SSA.

Pressure overload-induced mild cardiac hypertrophy reduces left ventricular transmural differences in mitochondrial respiratory chain activity and increases oxidative stress

Objective: Increased mechanical stress and contractility characterizes normal left ventricular (LV) subendocardium (Endo) but whether Endo mitochondrial respiratory chain complex activities is reduced as compared to subepicardium (Epi) and whether pressure overload-induced LV hypertrophy (LVH) might modulate transmural gradients through increased reactive oxygen species (ROS) production is unknown. Methods: LVH was induced by 6 weeks abdominal aortic banding and cardiac structure and function were determined with echocardiography and catheterization in sham-operated and LVH rats (n = 10 for each group). Mitochondrial respiration rates, coupling, content and ROS production were measured in LV Endo and Epi, using saponin-permeabilized fibers, Amplex Red fluorescence and citrate synthase activity. Results: In sham, a transmural respiratory gradient was observed with decreases in endo maximal oxidative capacity (−36.7%, P < 0.01) and complex IV activity (−57.4%, P < 0.05). Mitochondrial hydrogen peroxide (H₂O₂) production was similar in both LV layers. Aortic banding induced mild LVH (+31.7% LV mass), associated with normal LV fractional shortening and end diastolic pressure. LVH reduced maximal oxidative capacity (−23.6 and −33.3%), increased mitochondrial H₂O₂ production (+86.9 and +73.1%), free radical leak (+27.2% and +36.3%) and citrate synthase activity (+27.2% and +36.3%) in Endo and Epi, respectively. Transmural mitochondrial respiratory chain complex IV activity was reduced in LVH (−57.4 vs. −12.2%; P = 0.02). Conclusions: Endo mitochondrial respiratory chain complexes activities are reduced compared to LV Epi. Mild LVH impairs mitochondrial oxidative capacity, increases oxidative stress and reduces transmural complex IV activity. Further studies will be helpful to determine whether reduced LV transmural gradient in mitochondrial respiration might be a new marker of a transition from uncomplicated toward complicated LVH.

Contribution of central adiposity to left ventricular diastolic function (from the Baltimore Longitudinal Study of Aging)

We examined the relations of central adiposity with left ventricular (LV) diastolic dysfunction in men and women who participated in the Baltimore Longitudinal Study of Aging, a prospective community-based study of older persons. The sample for this cross-sectional analysis included 399 women and 370 men. Central adiposity was estimated using the waist circumference (WC) and global adiposity using the body mass index (BMI). Using data from a comprehensive echocardiographic study that included tissue Doppler imaging, diastolic function was graded according to 3 parameters (E/A ratio, E/Em ratio, and left atrial volume index). In the logistic regression models adjusted for age, gender, cardiovascular risk factors, and hemodynamic parameters, WC and BMI were both independently associated with LV diastolic dysfunction. However, when both WC and BMI were in the same model, only WC remained significantly associated with LV diastolic dysfunction (odds ratio 1.04, 95% confidence interval 1.01 to 1.08, p = 0.02). In the gender-stratified analyses, WC was significantly associated with LV diastolic dysfunction-independently of BMI-in women (odds ratio 1.08, 95% confidence interval 1.04 to 1.14, p <0.001) but not in men (odds ratio 1.00, 95% confidence interval 0.95 to 1.05, p = 0.91). Additional adjustment for LV mass index failed to modify these relations. In conclusion, the adverse effect of central adiposity on LV diastolic function was independent of general adiposity and more pronounced among women. The effect of visceral adiposity on LV diastolic dysfunction would benefit from confirmation in longitudinal studies.

Cardiac structure and function in relation to central blood pressure components in Chinese

BACKGROUND

Data are limited with regard to the association of central blood pressure (BP) components with cardiac structure and function.

METHODS

Our study was conducted in the framework of cardiovascular health examinations for the current and retired employees of a factory and their family members. We measured central BP by SphygmoCor and cardiac structure and function by echocardiography.

RESULTS

The 826 participants (mean age 43.0 years) included 285 (34.5%) women and 184 (22.3%) hypertensive patients, of whom 78 (42.4%) took antihypertensive drugs. After adjustment for age, sex, body weight, body height, antihypertensive treatment, current smoking and alcohol intake, left atrial volume and left ventricular mass were significantly associated with brachial and central BP components (r = 0.09-0.21, P ≤ 0.01), whereas left ventricular diastolic dysfunction, evaluated by E/A ratio and deceleration time of E wave (DTE), was only significantly associated with brachial and central SBP (r = 0.14-0.18, P < 0.001). However, these correlation coefficients were quantitatively but nonsignificantly different between brachial and central BP (P ≥ 0.06). In regression models with similar adjustments, with 1-SD increase in central SBP (16.7 mmHg), E/A ratio significantly decreased by 5.5 ± 1.2% and DTE significantly increased by 4.66 ± 1.22 ms (P < 0.001). Sensitivity analyses in men and women separately and after exclusion of patients on antihypertensive medication were confirmatory.

CONCLUSION

Cardiac structure was significantly and comparably associated with central BP components, but left ventricular diastolic dysfunction was only significantly associated with central SBP.

Effect of obesity and overweight on left ventricular diastolic function: a community-based study in an elderly cohort

OBJECTIVES

The purpose of this study was to assess the independent effect of increased body size on left ventricular (LV) diastolic function.

BACKGROUND

Obese and overweight persons are at increased risk of heart failure. Left ventricular diastolic dysfunction is an asymptomatic condition associated with future heart failure. It is unclear whether obesity and overweight are independently associated with LV diastolic dysfunction.

METHODS

The LV diastolic function was evaluated in 950 participants from the CABL (Cardiovascular Abnormalities and Brain Lesions) study by traditional and tissue Doppler imaging. Peak early transmitral diastolic flow velocity (E), late transmitral diastolic flow velocity (A), and early diastolic mitral annulus velocity (E') were measured, and E/A and E/E' were calculated. The study sample was divided into 3 groups: normal weight (body mass index [BMI] <25.0 kg/m(2)), overweight (BMI 25.0 to 29.9 kg/m(2)), and obese (BMI ≥30 kg/m(2)).

RESULTS

In multivariate analyses, BMI was independently associated with higher E, A, and E/E', an indicator of LV filling pressure (all p ≤ 0.01). Overweight and obese had lower E' (both p < 0.01) and higher E/E' (both p < 0.01) than normal weight participants. The E/A was lower in obese subjects than in normal weight subjects (p < 0.01). The risk of diastolic dysfunction was significantly higher in overweight subjects (adjusted odds ratio: 1.52, 95% confidence interval: 1.04 to 2.22) and obese subjects (adjusted odds ratio: 1.60, 95% confidence interval: 1.06 to 2.41) compared to normal weight subjects.

CONCLUSIONS

Increased BMI was associated with worse LV diastolic function independent of LV mass and associated risk factors. The increased risk of LV diastolic dysfunction in both overweight and obese persons may partially account for the increased risk of heart failure associated with both conditions.

Impact of 6-year body weight change on cardiac geometry and function in ageing adults: the SUpplémentation en Vitamines et Minéraux AntioXydants -2 (SU.VI.MAX-2) cardiovascular ultrasound substudy

BACKGROUND AND OBJECTIVE

Although the relationships between BMI and cardiac geometry and function have been established, information remains limited on the impact of BMI, waist circumference and body composition variations over time on echocardiographic changes in ageing adults.

METHODS AND RESULTS

Multiple linear regressions were used to correlate cardiac echographic parameters and baseline anthropometric data and their changes over 6 years in 280 participants of the SU.VI.MAX 2 cohort study. During the follow-up, BMI increased by 0.6 (95% confidence interval: 0.3-0.8) kg/m, waist circumference by 2.3 (1.6-3.0) cm and percentage body fat mass (%BFM) by 4.0 (3.4-4.6) %. A 6-year change (2001-2007) by 1 kg/m in BMI or 1 cm in waist circumference was associated with an increase in indexed left ventricular mass by 2.3 g/m (1.3-3.3, P < 0.001) and 0.4 g/m (0.06-0.6, P < 0.017), respectively, and an increase in left atrial area by 0.3 cm (0.1-0.5, P < 0.001) and 0.05 cm (0.003-0.10, P < 0.037), respectively. Follow-up left ventricular mass and left atrial area were not impacted by changes in percentage body fat mass. A significant correlation was observed between E-wave transmitral flow deceleration time and baseline BMI and waist circumference, but not with their changes over time.

CONCLUSION

Changes in anthropometric markers over time are associated with increased left ventricular mass and left atrial size. These findings reinforce the potential benefit of a healthy diet and lifestyle to maintain body weight and, in turn, cardiac geometry and function in ageing adults.

Waist circumference modifies the relationship between the adipose tissue cytokines leptin and adiponectin and all-cause and cardiovascular mortality in haemodialysis patients

BACKGROUND

the relationships between the adipose tissue cytokines leptin and adiponectin (ADPN) and clinical outcomes have not been well studied in haemodialysis (HD) patients and remain highly controversial. As central obesity is an important modifier of the effect of various risk factors for clinical outcomes, we tested the hypothesis that waist circumference (WC) modifies the link between these cytokines and both overall and cardiovascular death in HD patients.

METHODS

a total of 537 HD patients participated in a prospective cohort study.

RESULTS

leptin and ADPN were inversely related to each other and robustly associated with WC (P < 0.001). During follow-up (average 29 months, range 1-47 months) 182 patients died, including 115 from cardiovascular causes. In analyses adjusting for potential confounders, there were strong interactions between leptin and WC in relationship to both all-cause (P < 0.001) and cardiovascular death (P = 0.002). Accordingly, a fixed excess of leptin signalled a gradually increasing risk for all-cause and cardiovascular mortality in patients with a large WC but an opposite effect in those with a relatively small WC. An interaction between ADPN and WC for all-cause (P = 0.01) and cardiovascular mortality (P = 0.01) emerged only in models excluding the leptin-WC interaction, suggesting that these adipokines share a common pathway leading to adverse clinical events in HD patients.

CONCLUSIONS

the predictive value of leptin and ADPN for all-cause and cardiovascular death in HD patients appears to be critically dependent on WC. These findings support the hypothesis that disturbances in adipokine levels are involved in adverse clinical outcomes in HD patients with abdominal obesity.

Global cardiovascular risk profiles of untreated hypertensives in an urban, developing community in Africa

Introduction

Blood pressure (BP) control in people of African descent is poor, largely because of a lack of treatment. Although the requirements for immediate initiation of antihypertensive drug therapy are defined by global cardiovascular risk, the global cardiovascular risk profiles of untreated hypertensives at a community level are uncertain.

Aim

To identify the distribution of global cardiovascular risk profiles of untreated hypertensives in an urban, developing community of African descent in South Africa.

Methods

As part of the African Programme on Genes in Hypertension, we assessed nurse-derived clinic BP (the mean of five standardised BP values obtained according to guidelines), current antihypertensive therapy, and total cardiovascular risk in 1 029 participants older than 16 years of age from randomly selected nuclear families from the South West Township of Gauteng (SOWETO).

Results

Approximately 46% of participants had systolic/diastolic BP values ≥ 140/90 mmHg and ~23% of participants were hypertensives not receiving antihypertensive medication. Approximately 12% of untreated hypertensives had a high added risk and ~18% a very high added risk (6.7% of the total sample). In untreated hypertensives, in contrast to the absence of severe hypertension and diabetes mellitus in those with lower risk profiles, a high cardiovascular risk profile in this group was characterised by severe hypertension in ~52% and diabetes mellitus in ~33%. Based on a high added risk carrying at least a 20% chance and a very high added risk at least a 30% chance of a cardiovascular event in 10 years, this translates into 1 740 events per 100 000 of the population within 10 years, events that could be prevented through antihypertensive drug therapy.

Conclusions

In an urban, developing community of African ancestry, a significant proportion (6.7%) of people may have untreated hypertension and a global cardiovascular risk profile that suggests a need for antihypertensive drug therapy. Cardiovascular risk in this group is driven largely by the presence of severe hypertension or diabetes mellitus.

Body mass index and waist circumference in Mozambique: urban/rural gap during epidemiological transition

In 2005 we evaluated a nationally representative sample of the Mozambican adult population (n=2913; 25-64 years old) following the STEPwise approach to chronic disease risk factor surveillance to estimate urban-rural differences in overweight and obesity and waist circumferences. The prevalences of obesity and overweight were, respectively, 6.8% (95% CI: 5.1-8.6) and 11.8% (95% CI: 8.4-15.4) among women, and 2.3% (95% CI: 1.1-3.6) and 9.4% (95% CI: 5.7-13.1) among men. Overweight/obesity was more frequent in urban settings (age-, income- and education-adjusted prevalence ratios; women, 2.76, 95% CI: 1.82-4.18; men, 1.76, 95% CI: 0.80-3.85). The average waist circumference in Mozambique was 75.2cm (95% CI: 74.3-76.0) in women, significantly higher in urban than rural areas (age-, income- and education-adjusted β=3.6cm, 95% CI: 1.6-5.5) and 76.1cm (95% CI: 75.0-77.3) in men, with no urban-rural differences (adjusted β=1.3cm, 95% CI: -0.9 to 3.5). Our results show urban-rural differences, as expected in a country under epidemiological transition, with urban areas presenting a higher prevalence of overweight/obesity, but age- and education-specific estimates suggesting a trend towards smaller divergences. The development and implementation of strategies to manage the foreseeable obesity-related healthcare demands are needed.

Dietary-induced obesity hastens the progression from concentric cardiac hypertrophy to pump dysfunction in spontaneously hypertensive rats

We explored whether dietary-induced obesity hastens the transition from concentric left ventricular (LV) hypertrophy to pump dysfunction in spontaneously hypertensive rats (SHRs) and the mechanisms thereof. After feeding rats a diet for 4 to 5 months, obesity was induced in SHRs and Wistar-Kyoto (WKY) control rats. Obesity was not associated with abnormal blood glucose control (glycosylated hemoglobin) or with increases in systolic blood pressure. However, in SHRs, but not in WKY rats, obesity was associated with a reduced LV chamber systolic function, as determined by echocardiography, and in isolated perfused heart studies. A marked increase in LV end diastolic diameter and a right shift in the LV diastolic pressure-volume relation were noted in obese SHRs but not in obese WKY rats. Moreover, LV intrinsic myocardial systolic function, as determined from the slope of the linearized LV systolic stress-strain relationship (LV myocardial end systolic elastance), was markedly reduced in obese as compared with lean SHRs, whereas LV myocardial end systolic elastance was maintained in obese WKY rats. Obesity increased LV weight, cardiomyocyte width, cardiomyocyte apoptosis (TUNEL), the activity of myocardial matrix metalloproteinases (zymography), and serum leptin concentrations in SHRs but not in WKY rats. In conclusion, SHRs are susceptible to the adverse effects of dietary-induced obesity on the heart, an effect that hastens the progression from concentric LV hypertrophy to pump dysfunction independent of blood pressure changes or alterations in glycosylated hemoglobin. This effect may be mediated through a proclivity of SHRs to developing both obesity-induced effects on cardiomyocyte apoptosis and activation of myocardial collagenases through leptin resistance and obesity-induced hypertrophy.