Exercise training prevents diastolic dysfunction induced by metabolic syndrome in rats

OBJECTIVE: High fructose consumption contributes to the incidence of metabolic syndrome and, consequently, to cardiovascular outcomes. We investigated whether exercise training prevents high fructose diet-induced metabolic and cardiac morphofunctional alterations. METHODS: Wistar rats receiving fructose overload (F) in drinking water (100 g/l) were concomitantly trained on a treadmill (FT) for 10 weeks or kept sedentary. These rats were compared with a control group (C). Obesity was evaluated by the Lee index, and glycemia and insulin tolerance tests constituted the metabolic evaluation. Blood pressure was measured directly (Windaq, 2 kHz), and echocardiography was performed to determine left ventricular morphology and function. Statistical significance was determined by one-way ANOVA, with significance set at p<0.05. RESULTS: Fructose overload induced a metabolic syndrome state, as confirmed by insulin resistance (F: 3.6 +/- 0.2 vs. C: 4.5 +/- 0.2 mg/dl/min), hypertension (mean blood pressure, F: 118 +/- 3 vs. C: 104 +/- 4 mmHg) and obesity (F: 0.31 +/- 0.001 vs. C: 0.29 +/- 0.001 g/mm). Interestingly, fructose overload rats also exhibited diastolic dysfunction. Exercise training performed during the period of high fructose intake eliminated all of these derangements. The improvements in metabolic parameters were correlated with the maintenance of diastolic function. CONCLUSION: The role of exercise training in the prevention of metabolic and hemodynamic parameter alterations is of great importance in decreasing the cardiac morbidity and mortality related to metabolic syndrome.

RHYTHM-AF: design of an international registry on cardioversion of atrial fibrillation and characteristics of participating centers

Background: Atrial fibrillation is a serious public health problem posing a considerable burden to not only patients, but the healthcare environment due to high rates of morbidity, mortality, and medical resource utilization. There are limited data on the variation in treatment practice patterns across different countries, healthcare settings and the associated health outcomes. Methods/design: RHYTHM-AF was a prospective observational multinational study of management of recent onset atrial fibrillation patients considered for cardioversion designed to collect data on international treatment patterns and short term outcomes related to cardioversion. We present data collected in 10 countries between May 2010 and June 2011. Enrollment was ongoing in Italy and Brazil at the time of data analysis. Data were collected at the time of atrial fibrillation episode in all countries (Australia, Brazil, France, Germany, Italy, Netherlands, Poland, Spain, Sweden, United Kingdom), and cumulative follow-up data were collected at day 60 (+/- 10) in all but Spain. Information on center characteristics, enrollment data, patient demographics, detail of atrial fibrillation episode, medical history, diagnostic procedures, acute treatment of atrial fibrillation, discharge information and the follow-up data on major events and rehospitalizations up to day 60 were collected. Discussion: A total of 3940 patients were enrolled from 175 acute care centers. 70.5% of the centers were either academic (44%) or teaching (26%) hospitals with an overall median capacity of 510 beds. The sites were mostly specialized with anticoagulation clinics (65.9%), heart failure (75.1%) and hypertension clinics (60.1%) available. The RHYTHM-AF registry will provide insight into regional variability of antiarrhythmic and antithrombotic treatment of atrial fibrillation, the appropriateness of such treatments with respect to outcomes, and their cost-efficacy. Observations will help inform strategies to improve cardiovascular outcomes in patients with atrial fibrillation.

Subclinical hyperthyroidism and the risk of coronary heart disease and mortality

Data from prospective cohort studies regarding the association between subclinical hyperthyroidism and cardiovascular outcomes are conflicting.We aimed to assess the risks of total and coronary heart disease (CHD) mortality, CHD events, and atrial fibrillation (AF) associated with endogenous subclinical hyperthyroidism among all available large prospective cohorts.

Cross-cultural analysis of type D (distressed) personality in 6222 patients with ischemic heart disease: a study from the International HeartQoL Project

BACKGROUND Type D (distressed) personality, the conjoint effect of negative affectivity (NA) and social inhibition (SI), predicts adverse cardiovascular outcomes, and is assessed with the 14-item Type D Scale (DS14). However, potential cross-cultural differences in Type D have not been examined yet in a direct comparison of countries. AIM To examine the cross-cultural validity of the Type D construct and its relation with cardiovascular risk factors, cardiac symptom severity, and depression/anxiety. METHODS In 22 countries, 6222 patients with ischemic heart disease (angina, 33%; myocardial infarction, 37%; or heart failure, 30%) completed the DS14 as part of the International HeartQoL Project. RESULTS Type D personality was assessed reliably across countries (αNA>.80; αSI>.74; except Russia, which was excluded from further analysis). Cross-cultural measurement equivalence was established for Type D personality at all measurement levels, as the factor-item configuration, factor loadings, and error structure were not different across countries (fit: CFI=.91; NFI=.88; RMSEA=.018), as well as across gender and diagnostic subgroups. Type D personality was more prevalent in Southern (37%) and Eastern (35%) European countries compared to Northern (24%) and Western European and English-speaking (both 27%) countries (p<.001). Type D was not confounded by cardiac symptom severity, but was associated with a higher prevalence of hypertension, smoking, sedentary lifestyle, and depression. CONCLUSION Cross-cultural measurement equivalence was demonstrated for the Type D scale in 21 countries. There is a pan-cultural relationship between Type D personality and some cardiovascular risk factors, supporting the role of Type D personality across countries and cardiac conditions.

Clinical impact of gastrointestinal bleeding in patients undergoing percutaneous coronary interventions.

BACKGROUND The risk factors and clinical sequelae of gastrointestinal bleeding (GIB) in the current era of drug-eluting stents, prolonged dual antiplatelet therapy, and potent P2Y12 inhibitors are not well established. We determined the frequency, predictors, and clinical impact of GIB after percutaneous coronary interventions (PCIs) in a contemporary cohort of consecutive patients treated with unrestricted use of drug-eluting stents. METHODS AND RESULTS Between 2009 and 2012, all consecutive patients undergoing PCI were prospectively included in the Bern PCI Registry. Bleeding Academic Research Consortium (BARC) GIB and cardiovascular outcomes were recorded within 1 year of follow-up. Among 6212 patients, 84.1% received new-generation drug-eluting stents and 19.5% received prasugrel. At 1 year, GIB had occurred in 65 patients (1.04%); 70.8% of all events and 84.4% of BARC ≥3B events were recorded >30 days after PCI. The majority of events (64.4%) were related to upper GIB with a more delayed time course compared with lower GIB. Increasing age, previous GIB, history of malignancy, smoking, and triple antithrombotic therapy (ie, oral anticoagulation plus dual antiplatelet therapy) were independent predictors of GIB in multivariable analysis. GIB was associated with increased all-cause mortality (adjusted hazard ratio, 3.40; 95% confidence interval, 1.67-6.92; P=0.001) and the composite of death, myocardial infarction, or stroke (adjusted hazard ratio, 3.75; 95% confidence interval, 1.99-7.07; P<0.001) and was an independent predictor of all-cause mortality during 1 year. CONCLUSIONS Among unselected patients undergoing PCI, GIB has a profound effect on prognosis. Triple antithrombotic therapy emerged as the single drug-related predictor of GIB in addition to patient-related risk factors within 1 year of PCI. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT02241291.

Inactive Matrix Gla-Protein Is Associated With Arterial Stiffness in an Adult Population-Based Study

Increased pulse wave velocity (PWV) is a marker of aortic stiffness and an independent predictor of mortality. Matrix Gla-protein (MGP) is a vascular calcification inhibitor that needs vitamin K to be activated. Inactive MGP, known as desphospho-uncarboxylated MGP (dp-ucMGP), can be measured in plasma and has been associated with various cardiovascular markers, cardiovascular outcomes, and mortality. In this study, we hypothesized that high levels of dp-ucMGP are associated with increased PWV. We recruited participants via a multicenter family-based cross-sectional study in Switzerland. Dp-ucMGP was quantified in plasma by sandwich ELISA. Aortic PWV was determined by applanation tonometry using carotid and femoral pulse waveforms. Multiple regression analysis was performed to estimate associations between PWV and dp-ucMGP adjusting for age, renal function, and other cardiovascular risk factors. We included 1001 participants in our analyses (475 men and 526 women). Mean values were 7.87±2.10 m/s for PWV and 0.43±0.20 nmol/L for dp-ucMGP. PWV was positively associated with dp-ucMGP both before and after adjustment for sex, age, body mass index, height, systolic and diastolic blood pressure (BP), heart rate, renal function, low- and high-density lipoprotein, glucose, smoking status, diabetes mellitus, BP and cholesterol lowering drugs, and history of cardiovascular disease (P≤0.01). In conclusion, high levels of dp-ucMGP are independently and positively associated with arterial stiffness after adjustment for common cardiovascular risk factors, renal function, and age. Experimental studies are needed to determine whether vitamin K supplementation slows arterial stiffening by increasing MGP carboxylation.

Role of stress myocardial perfusion scan in pre-operative evaluation of cancer patients undergoing non-cardiac surgery

Background. Cardiac risk assessment in cancer patients has not extensively been studied. We evaluated the role of stress myocardial perfusion imaging (MPI) in predicting cardiovascular outcomes in cancer patients undergoing non-cardiac surgery. ^ Methods. A retrospective chart review was performed on 507 patients who had a MPI from 01/2002 - 03/2003 and underwent non-cardiac surgery. Median follow-up duration was 1.5 years. Cox proportional hazard model was used to determine the time-to-first event. End points included total cardiac events (cardiac death, myocardial infarction (MI) and coronary revascularization), cardiac death, and all cause mortality. ^ Results. Of all 507 MPI studies 146 (29%) were abnormal. There were significant differences in risk factors between normal and abnormal MPI groups. Mean age was 66±11 years, with 60% males and a median follow-up duration of 1.8 years (25th quartile=0.8 years, 75th quartile=2.2 years). The majority of patients had an adenosine stress study (53%), with fewer exercise (28%) and dobutamine stress (16%) studies. In the total group there were 39 total cardiac events, 31 cardiac deaths, and 223 all cause mortality events during the study. Univariate predictors of total cardiac events included CAD (p=0.005), previous MI (p=0.005), use of beta blockers (p=0.002), and not receiving chemotherapy (p=0.012). Similarly, the univariate predictors of cardiac death included previous MI (p=0.019) and use of beta blockers (p=0.003). In the multivariate model for total cardiac events, age at surgery (HR 1.04, p=0.030), use of beta blockers (HR 2.46; p=0.011), dobutamine MPI (HR 3.08; p=0.018) and low EF (HR 0.97; p=0.02) were significant predictors of worse outcomes. In the multivariate model for predictors of cardiac death, beta blocker use (HR=2.74; p=0.017) and low EF (HR=0.95; p<0.003) were predictors of cardiac death. The only univariate MPI predictor of total cardiac events was scar severity (p=0.005). While MPI predictors of cardiac death were scar severity (p= 0.001) and ischemia severity (p=0.02). ^ Conclusions. Stress MPI is a useful tool in predicting long term outcomes in cancer patients undergoing surgery. Ejection fraction and severity of myocardial scar are important factors determining long term outcomes in this group.^

Fibroblast growth factor 23 and markers of mineral metabolism in individuals with preserved renal function

Fibroblast growth factor 23 (FGF23) is a bone-derived hormone that regulates phosphate homeostasis. Circulating FGF23 is elevated in chronic kidney disease (CKD) and independently associated with poor renal and cardiovascular outcomes and mortality. Because the study of FGF23 in individuals with normal renal function has received little attention, we examined in a large, population based study of 1128 participants the associations of FGF23 with markers of mineral metabolism and renal function. The median estimated glomerular filtration rate (eGFR) of the cohort was 105 ml/min per 1.73 m2, and the median plasma FGF23 was 78.5 RU/ml. FGF23 increased and plasma 1,25-dihydroxyvitamin D3 decreased significantly below an eGFR threshold of 102 and 99 ml/min per 1.73 m2, respectively. In contrast, plasma parathyroid hormone increased continuously with decreasing eGFR and was first significantly elevated at an eGFR of 126 ml/min per 1.73 m2. On multivariable analysis adjusting for sex, age, body mass index, and GFR, FGF23 was negatively associated with 1,25-dihydroxyvitamin D3, and urinary absolute and fractional calcium excretion but not with serum calcium or parathyroid hormone. We found a positive association of FGF23 with plasma phosphate, but no association with urinary absolute or fractional phosphate excretion and, unexpectedly, a positive association with tubular maximum phosphate reabsorption/GFR. Thus, in the absence of CKD, parathyroid hormone increases earlier than FGF23 when the eGFR decreases. The increase in FGF23 occurs at a higher eGFR threshold than previously reported and is closely associated with a decrease in 1,25-dihydroxyvitamin D3. We speculate that the main demonstrable effect of FGF23 in the setting of preserved renal function is suppression of 1,25-dihydroxyvitamin D3 rather than stimulation of renal phosphate excretion.

Homocysteine-lowering therapy in renal disease

Hyperhomocysteinemia is a potential risk factor for vascular disease and is associated with endothelial dysfunction, a predictor of adverse cardiovascular events. Renal patients (end-stage renal failure (ESRF) and transplant recipients (RTR)) exhibit both hyperhomocysteinemia and endothelial dysfunction with increasing evidence of a causative link between the 2 conditions. The elevated homocysteine appears to be due to altered metabolism in the kidney (intrarenal) and in the uremic circulation ( extrarenal). This review will discuss 18 supplementation studies conducted in ESRF and 6 in RTR investigating the effects of nutritional therapy to lower homocysteine. The clinical significance of lowering homocysteine in renal patients will be discussed with data on the effects of B vitamin supplementation on cardiovascular outcomes such as endothelial function presented. Folic acid is the most effective nutritional therapy to lower homocysteine. In ESRF patients, supplementation with folic acid over a wide dose range ( 2 - 20 mg/day) either individually or in combination with other B vitamins will decrease but not normalize homocysteine. In contrast, in RTR similar doses of folic acid normalizes homocysteine. Folic acid improves endothelial function in ESRF patients, however this has yet to be investigated in RTR. Homocysteine-lowering therapy is more effective in ESRF patients than RTR.

Alogliptin after acute coronary syndrome in patients with type 2 diabetes

Background - To assess potentially elevated cardiovascular risk related to new antihyperglycemic drugs in patients with type 2 diabetes, regulatory agencies require a comprehensive evaluation of the cardiovascular safety profile of new antidiabetic therapies. We assessed cardiovascular outcomes with alogliptin, a new inhibitor of dipeptidyl peptidase 4 (DPP-4), as compared with placebo in patients with type 2 diabetes who had had a recent acute coronary syndrome. Methods - We randomly assigned patients with type 2 diabetes and either an acute myocardial infarction or unstable angina requiring hospitalization within the previous 15 to 90 days to receive alogliptin or placebo in addition to existing antihyperglycemic and cardiovascular drug therapy. The study design was a double-blind, noninferiority trial with a prespecified noninferiority margin of 1.3 for the hazard ratio for the primary end point of a composite of death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke. Results - A total of 5380 patients underwent randomization and were followed for up to 40 months (median, 18 months). A primary end-point event occurred in 305 patients assigned to alogliptin (11.3%) and in 316 patients assigned to placebo (11.8%) (hazard ratio, 0.96; upper boundary of the one-sided repeated confidence interval, 1.16; P<0.001 for noninferiority). Glycated hemoglobin levels were significantly lower with alogliptin than with placebo (mean difference, -0.36 percentage points; P<0.001). Incidences of hypoglycemia, cancer, pancreatitis, and initiation of dialysis were similar with alogliptin and placebo. Conclusions - Among patients with type 2 diabetes who had had a recent acute coronary syndrome, the rates of major adverse cardiovascular events were not increased with the DPP-4 inhibitor alogliptin as compared with placebo. (Funded by Takeda Development Center Americas; EXAMINE ClinicalTrials.gov number, NCT00968708.)

Hypertension, poor glycemic control, and microalbuminuria in Cuban Americans with type 2 diabetes

Purpose: To investigate to what degree the presence of hypertension (HTN) and poor glycemic control (GC) influences the likelihood of having microalbuminuria (MAU) among Cuban Americans with type 2 diabetes (T2D).Methods: A cross-sectional study conducted in Cuban Americans (n = 179) with T2D. Participants were recruited from a randomly generated mailing list purchased from KnowledgeBase Marketing, Inc. Blood pressure (BP) was measured twice and averaged using an adult size cuff. Glycosylated hemoglobin (A1c) levels were measured from whole blood samples with the Roche Tina-quant method. First morning urine samples were collected from each participant to determine MAU by a semiquantitative assay (ImmunoDip).Results: MAU was present in 26% of Cuban Americans with T2D. A significantly higher percentage of subjects with MA had HTN (P = 0.038) and elevated A1C (P = 0.002) than those with normoalbuminuria. Logistic regression analysis showed that after controlling for covariates, subjects with poor GC were 6.76 times more likely to have MAU if they had hypertension compared with those without hypertension (P = 0.004; 95% confidence interval [CI]: 1.83, 23.05). Conclusion: The clinical significance of these findings emphasizes the early detection of MAU in this Hispanic subgroup combined with BP and good GC, which are fundamentals in preventing and treating diabetes complications and improving individuals’ renal and cardiovascular outcomes.

Importance of risk factor management in diabetic patients and reduction in Stage B heart failure

BACKGROUND: A number of studies have demonstrated the presence of a diabetic cardiomyopathy, increasing the risk of heart failure development in this population. Improvements in present-day risk factor control may have modified the risk of diabetes-associated cardiomyopathy.

AIM: We sought to determine the contemporary impact of diabetes mellitus (DM) on the prevalence of cardiomyopathy in at-risk patients with and without adjustment for risk factor control.

DESIGN: A cross-sectional study in a population at risk for heart failure.

METHODS: Those with diabetes were compared to those with other cardiovascular risk factors, unmatched, matched for age and gender and then matched for age, gender, body mass index, systolic blood pressure and low density lipoprotein cholesterol.

RESULTS: In total, 1399 patients enrolled in the St Vincent's Screening to Prevent Heart Failure (STOP-HF) cohort were included. About 543 participants had an established history of DM. In the whole sample, Stage B heart failure (asymptomatic cardiomyopathy) was not found more frequently among the diabetic cohort compared to those without diabetes [113 (20.8%) vs. 154 (18.0%), P = 0.22], even when matched for age and gender. When controlling for these risk factors and risk factor control Stage B was found to be more prevalent in those with diabetes [88 (22.2%)] compared to those without diabetes [65 (16.4%), P = 0.048].

CONCLUSION: In this cohort of patients with established risk factors for Stage B heart failure superior risk factor management among the diabetic population appears to dilute the independent diabetic insult to left ventricular structure and function, underlining the importance and benefit of effective risk factor control in this population on cardiovascular outcomes.

Modest elevation in BNP in asymptomatic hypertensive patients reflects sub-clinical cardiac remodeling, inflammation and extracellular matrix changes

In asymptomatic subjects B-type natriuretic peptide (BNP) is associated with adverse cardiovascular outcomes even at levels well below contemporary thresholds used for the diagnosis of heart failure. The mechanisms behind these observations are unclear. We examined the hypothesis that in an asymptomatic hypertensive population BNP would be associated with sub-clinical evidence of cardiac remodeling, inflammation and extracellular matrix (ECM) alterations. We performed transthoracic echocardiography and sampled coronary sinus (CS) and peripheral serum from patients with low (n = 14) and high BNP (n = 27). Peripheral BNP was closely associated with CS levels (r = 0.92, p<0.001). CS BNP correlated significantly with CS levels of markers of collagen type I and III turnover including: PINP (r = 0.44, p = 0.008), CITP (r = 0.35, p = 0.03) and PIIINP (r = 0.35, p = 0.001), and with CS levels of inflammatory cytokines including: TNF-α (r = 0.49, p = 0.002), IL-6 (r = 0.35, p = 0.04), and IL-8 (r = 0.54, p<0.001). The high BNP group had greater CS expression of fibro-inflammatory biomarkers including: CITP (3.8±0.7 versus 5.1±1.9, p = 0.007), TNF-α (3.2±0.5 versus 3.7±1.1, p = 003), IL-6 (1.9±1.3 versus 3.4±2.7, p = 0.02) and hsCRP (1.2±1.1 versus 2.4±1.1, p = 0.04), and greater left ventricular mass index (97±20 versus 118±26 g/m(2), p = 0.03) and left atrial volume index (18±2 versus 21±4, p = 0.008). Our data provide insight into the mechanisms behind the observed negative prognostic impact of modest elevations in BNP and suggest that in an asymptomatic hypertensive cohort a peripheral BNP measurement may be a useful marker of an early, sub-clinical pathological process characterized by cardiac remodeling, inflammation and ECM alterations.

Methods for Confounding Adjustment and High-Dimensional Environmental Exposures

Thesis (Ph.D.)--University of Washington, 2016-08

Statin Adherence, Utilisation, and Prescribing Patterns. Improving effectiveness of treatment

Statins are one of the most widely studied and evidence-based medications. Randomised controlled trials have provided convincing evidence on the benefits of statin therapy in preventing cardiovascular events. Despite proven benefits, low costs, and few adverse effects, everyday effectiveness of statins is limited, since adherence to statin therapy is poor. This thesis was conducted as four pharmacoepidemiological studies using register data on statin users in real clinical care. The main purpose of the study was to evaluate prescribing patterns and to discover the lifestyle factors predicting statin nonadherence and discontinuation. This knowledge is essential in order to help physicians to motivate the adherence of their patients to treatment. In Finland, from 1998 to 2004, the number of statin initiators nearly doubled. The discovered channelling of atorvastatin and simvastatin may have affected the treatment outcomes at the public health level. It is possible that money spent on statins in Finland in 1998‒2004 could have been used in a more cost-effective way. In 2015, the percentage of patients receiving reimbursement for statins was 12% of the total population. Thus, it is a major public health and economic challenge to improve statin effectiveness and allocate therapy correctly. Among the participants with cardiovascular comorbidities, risky alcohol use or clustering of lifestyle risks were predictors of nonadherence. In addition, the prevalence of nonadherence to statins increased after retirement among both men and women. This increase in post-retirement nonadherence was highest among those receiving statins for secondary prevention. Discontinuation of statin therapy was predicted by high patient co-payment, and in women, by risky alcohol use. Recognising the predictors of nonadherence to statins is important because nonadherence is associated with an increased risk of adverse cardiovascular outcomes and higher healthcare costs. In conclusion, optimal outcomes in medical therapy require both efficacious medications and adherence to those treatments. When prescribing statins to eligible patients, the physician’s clinical expertise in recognising patients at risk of statin discontinuation and nonadherence, as well as their ability to increase adherence, may have a great effect on public health.