Hypertension in obesity Mendoza, Michael F; Kachur, Sergey M; Lavie, Carl J
Current opinion in cardiology,
2020-July, Letnik:
35, Številka:
4
Journal Article
Recenzirano
The obesity epidemic is progressively affecting majority of individuals worldwide leading to many adverse metabolic and cardiovascular outcomes. Increasingly concerning among them is obesity ...hypertension (HTN). In this review, we delve into the physiology and therapeutic options in obesity HTN as we discuss the implications of obesity HTN on society.
Obesity is the most common cause of primary HTN and is directly proportional to increases BMI. The significance of adiposity in obesity HTN centers on humoral mechanisms via stimulation of the renal-angiotensin system, leptin activity, sympathetic overdrive, and proinflammatory processes that potentiate vascular remodeling, which results in a higher incidence of the progression of many known serious cardiovascular diseases. Although lifestyle and medical therapies have been recommended for obesity and its sequelae, continued global progression of this disease has driven the development of newer therapies such as carotid baroreflex activation therapy, renal denervation, and selective leptin receptor antagonism.
The pathophysiology of obesity HTN has not yet been fully elucidated despite it being one of the oldest known diseases to mankind. Major efforts to understand obesity HTN endures, paving opportunities for newer and possibly superior therapeutic options.
The Effects of Exercise on Lipid Biomarkers Mendoza, Michael Vaughn F; Kachur, Sergey M; Lavie, Carl J
Methods in molecular biology (Clifton, N.J.),
2022, Letnik:
2343
Journal Article
The World Health Organization has declared obesity to be a global epidemic that increases cardiovascular disease (CVD) mortality risk factors, such as hypertension, diabetes, dyslipidemia, and ...atherosclerosis. The increasing ratio of time spent in sedentary activities to that spent performing physically demanding tasks increases the trends to obesity and susceptibility to these risk factors. Dyslipidemia is the foundation of atherosclerotic buildup and lipoproteins serve as cofactors to the inflammatory processes that destabilize plaques. Increasing cardiorespiratory fitness and muscular strength helps attenuate concentrations of low-density lipoproteins (LDLs), such as LDL cholesterol, and increase levels of high-density lipoprotein cholesterol, as well as reduce proprotein convertase subtilisin kexin type 9 expression. Effects of physical activity on the inflammatory pathways of atherosclerosis, specifically C-reactive protein, are more closely related to reducing the levels of adiposity in tandem with increasing fitness, than with exercise training alone. The purpose of this review is to describe the physiology of dyslipidemia and relate it to CVD and exercise therapies.
Background
Composite invasive and non-invasive data consistently demonstrate that resting myocardial blood flow (rMBF) in regions of known transmural myocardial scar (TMS) converge on a value of ~ ...0.30 mL/min/g or lower. This value has been confirmed using the 3 most common myocardial perfusion agents (
13
N,
15
O-H
2
O and
82
Rb) incorporating various kinetic models on older 2D positron emission tomography (PET) systems. Thus, rMBF in regions of TMS can serve as a reference “truth” to evaluate low-end accuracy of various PET systems and software packages (SWPs). Using
82
Rb on a contemporary 3D-PET-CT system, we sought to determine whether currently available SWP can accurately and precisely measure rMBF in regions of known TMS.
Results
Median rMBF (in mL/min/g) and COV in regions of TMS were 0.71 IQR 0.52–1.02 and 0.16 with 4DM; 0.41 0.34–0.54 and 0.10 with 4DM-FVD; 0.66 0.51–0.85 and 0.11 with Cedars; 0.51 0.43–0.61 and 0.08 with Emory-Votaw; 0.37 0.30–0.42, 0.07 with Emory-Ottawa, and 0.26 0.23–0.32, COV 0.07 with HeartSee.
Conclusions
SWPs varied widely in low end accuracy based on measurement of rMBF in regions of known TMS. 3D PET using
82
Rb and HeartSee software accurately (0.26 mL/min/g, consistent with established values) and precisely (COV = 0.07) quantified rMBF in regions of TMS. The Emory-Ottawa software yielded the next-best accuracy (0.37 mL/min/g), though rMBF was higher than established gold-standard values in ~ 5% of the resting scans. 4DM, 4DM-FDV, Cedars and Emory-Votaw SWP consistently resulted values higher than the established gold standard (0.71, 0.41, 0.66, 0.51 mL/min/g, respectively), with higher interscan variability (0.16, 0.11, 0.11, and 0.09, respectively).
Trial registration
: clinicaltrial.gov, NCT05286593, Registered December 28, 2021,
https://clinicaltrials.gov/ct2/show/NCT05286593
.
Phylogenetic reconstruction using molecular data is often subject to homoplasy, leading to inaccurate conclusions about phylogenetic relationships among operational taxonomic units. Compared with ...other molecular markers, single-nucleotide polymorphisms (SNPs) exhibit extremely low mutation rates, making them rare in recently emerged pathogens, but they are less prone to homoplasy and thus extremely valuable for phylogenetic analyses. Despite their phylogenetic potential, ascertainment bias occurs when SNP characters are discovered through biased taxonomic sampling; by using whole-genome comparisons of five diverse strains of Bacillus anthracis to facilitate SNP discovery, we show that only polymorphisms lying along the evolutionary pathway between reference strains will be observed. We illustrate this in theoretical and simulated data sets in which complex phylogenetic topologies are reduced to linear evolutionary models. Using a set of 990 SNP markers, we also show how divergent branches in our topologies collapse to single points but provide accurate information on internodal distances and points of origin for ancestral clades. These data allowed us to determine the ancestral root of B. anthracis, showing that it lies closer to a newly described "C" branch than to either of two previously described "A" or "B" branches. In addition, subclade rooting of the C branch revealed unequal evolutionary rates that seem to be correlated with ecological parameters and strain attributes. Our use of nonhomoplastic whole-genome SNP characters allows branch points and clade membership to be estimated with great precision, providing greater insight into epidemiological, ecological, and forensic questions.
Cardiac rehabilitation (CR) is a form of prescribed exercise that is a multidisciplinary approach designed to improve cardiac function and quality of life following major adverse cardiovascular ...events. In this comprehensive overview, we will describe the individual components of exercise training and discuss the preset doses for effective CR based on recent meta-analyses. We will also review the effects of prescribed exercise medicine on outcomes such as psychosocial stress factors, cardiorespiratory fitness, and survival and their individualized impact on special populations.
The association of cardiovascular disease (CVD) and psychosocial stress (PSS) is a bidirectional function, whereby the two conditions create a self-reinforcing feedback loop. Either can incite and/or ...magnify the other, prognosis consequently deteriorates and spontaneous remission is unlikely. Several studies show that even subclinical PSS increases mortality. Recent evidence suggests that stress exhibits a strong dose–response toxicity on cardiovascular health with increased levels of PSS directly correlating to additional morbidity and mortality. As such, it will be important that future research considers PSS as a continuous variable capable of causing a spectrum of disease. This article proposes targeted exercise routines as the most efficient therapy for both arms of the feedback loop. A consistent body of data indicates that regular physical activity eases the PSS burden while simultaneously lowering CVD risk. Exercise therapy, mindfulness training, and interventions targeting positive psychological well-being stress management are indispensable therapies, particularly for at-risk and already established cardiovascular patients. Indeed, comprehensive cardiac rehabilitation and exercise training programs inclusive of education, lifestyle, and psychological measures in addition to fitness training are a potent multifaceted therapy for improving quality of life and overall prognosis.
Abstract Background Depression is associated with increased mortality in stable coronary heart disease. Cardiac rehabilitation and exercise training has been shown to decrease depression, ...psychological stress, and mortality after a coronary heart disease event. The presence of depression at completion of cardiac rehabilitation and exercise training is associated with increased mortality. However, it is unknown if depression with comorbid psychological risk factors such as anxiety or hostility confers an additional mortality disadvantage. We evaluated the mortality effect of anxiety and hostility on depression after cardiac rehabilitation and exercise training. Patients and Methods We studied 1150 patients with coronary heart disease following major coronary heart disease events who had completed formal cardiac rehabilitation and exercise training. Using Kellner questionnaires, stress levels were measured in 1 of 3 domains: anxiety, hostility, and depression (with an aggregated overall psychological stress score) and divided into 3 groups: nondepressed (n = 1072), depression alone (n = 18), and depression with anxiety or hostility (n = 60). Subjects were analyzed for all-cause mortality over 161 months of follow-up (mean 6.4 years) by National Death Index. Results Depression after cardiac rehabilitation was not common (6.8%; mortality 20.8%) but when present, frequently associated with either anxiety or hostility (77% of depressed patients; mortality 22.0%). After adjustment for age, sex, ejection fraction, and baseline peak oxygen consumption, depression alone (hazard ratio HR 1.73, P = .04), as well as depression with comorbid psychological stress, was associated with higher mortality (HR 1.98, P = .03). Furthermore, our data showed an increased mortality when both anxiety and hostility were present in addition to depression after cardiac rehabilitation (HR 2.41, P = .04). Conclusions After cardiac rehabilitation, depression, when present, is usually associated with other forms of psychological stress, which confers additional mortality. More measures are needed to address psychological stress after cardiac rehabilitation.
To evaluate the effects of body composition as a function of lean mass index (LMI) and body fat (BF) on the correlation between increasing body mass index (BMI; calculated as the weight in kilograms ...divided by the height in meters squared) and decreasing mortality, which is known as the obesity paradox.
We retrospectively assessed 47,866 patients with preserved left ventricular ejection fraction (≥50%). We calculated BF by using the Jackson-Pollock equation and LMI using (1 - BF) × BMI. The population was divided according to the sex-adjusted BMI classification, sex-adjusted LMI classification, and sex-adjusted BF tertiles. The population was analyzed by using multivariate analysis for total mortality over a mean follow-up duration of 3.1 years by using the National Death Index, adjusting for left ventricular ejection fraction, left ventricular mass index, age, sex, and relative wall thickness.
In the entire population, higher BMI was narrowly associated (hazard ratio HR, 0.99; P<.001) with lower mortality. The higher LMI group was clearly protective (HR, 0.71; P<.001), whereas BF tertile was associated with lower mortality only if no adjustment was made for LMI (HR, 0.87; P<.001 without LMI; HR, 0.97; P=.23 with LMI). In the lean patients, low BMI was clearly associated with higher mortality (HR, 0.92; P<.001) and lower BF tertile was associated with lower mortality only if no adjustment was made for LMI (HR, 0.80; P<.001 without LMI; HR, 1.01; P=.83 with LMI). The underweight patients stratified by BF seemed to have an increased mortality (HR, 1.91; 95% CI, 1.56-2.34) that was independent of LMI. However, in obese patients, both BMI (HR, 1.03; P<.001) and BF (HR, 1.18; P=.003) were associated with higher mortality, even after adjusting for LMI, which remained protective (HR, 0.57; P<.001) independently of BF.
Body composition could explain the inverse J shape of the mortality curve noted with increasing BMI. Body fat seems to be protective in this cohort only if no adjustment was made for LMI, although being underweight stratified by BF seems to be an independent risk factor. Lean mass index seems to remain protective in obese patients even when BMI is not.
Anthrax, caused by the bacterium Bacillus anthracis, is a disease of historical and current importance that is found throughout the world. The basis of its historical transmission is anecdotal and ...its true global population structure has remained largely cryptic. Seven diverse B. anthracis strains were whole-genome sequenced to identify rare single nucleotide polymorphisms (SNPs), followed by phylogenetic reconstruction of these characters onto an evolutionary model. This analysis identified SNPs that define the major clonal lineages within the species. These SNPs, in concert with 15 variable number tandem repeat (VNTR) markers, were used to subtype a collection of 1,033 B. anthracis isolates from 42 countries to create an extensive genotype data set. These analyses subdivided the isolates into three previously recognized major lineages (A, B, and C), with further subdivision into 12 clonal sub-lineages or sub-groups and, finally, 221 unique MLVA15 genotypes. This rare genomic variation was used to document the evolutionary progression of B. anthracis and to establish global patterns of diversity. Isolates in the A lineage are widely dispersed globally, whereas the B and C lineages occur on more restricted spatial scales. Molecular clock models based upon genome-wide synonymous substitutions indicate there was a massive radiation of the A lineage that occurred in the mid-Holocene (3,064-6,127 ybp). On more recent temporal scales, the global population structure of B. anthracis reflects colonial-era importation of specific genotypes from the Old World into the New World, as well as the repeated industrial importation of diverse genotypes into developed countries via spore-contaminated animal products. These findings indicate humans have played an important role in the evolution of anthrax by increasing the proliferation and dispersal of this now global disease. Finally, the value of global genotypic analysis for investigating bioterrorist-mediated outbreaks of anthrax is demonstrated.
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