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Metabolic syndrome (MetS) is characterized by adiposity and atherogenic dyslipidemia consisting of elevated triglyceride and decreased high density lipoprotein cholesterol (HDL-C) levels however, cholesterol concentration alone does not reflect HDL functionality. Cholesterol efflux capacity (CEC) captures a key anti-atherosclerotic function of HDL; studies linking CEC to MetS have yielded inconsistent findings and lacked racial/ethnic diversity. The aim of this study was to evaluate the association between CEC and MetS in a large multi-ethnic population utilizing two different CEC assays interrogating overlapping but distinct reverse cholesterol transport pathways. A cross-sectional study was performed using the Dallas Heart Study cohort and cholesterol efflux was measured with radiolabeled and fluorescent cholesterol assays. The relationship between CEC and MetS was assessed using multivariable regression analyses. A total of 2241 participants were included (mean age was 50 years; 38% men and 53% Blacks). CEC was independently and inversely associated with MetS irrespective of efflux assay (CEC-radiolabeled, adjusted OR 0·71 [95% CI 0·65–0·80]. CEC-fluorescent, adjusted OR 0·85 [95% CI 0·77–0·94]). Both CEC measures were inversely associated with waist circumference and directly associated with HDL-C but not with other MetS components. There was an interaction by sex but not by race such that the inverse associations between CEC and MetS were somewhat attenuated in men (OR 0·86, 95%CI 0·74–1·01). In this large multi-ethnic cohort, impaired CEC is linked to MetS irrespective of efflux assay and race/ethnicity but less so among men. Future studies are needed to assess whether CEC mediates the atherosclerotic cardiovascular disease risk of MetS. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to determine the effects of empagliflozin on glycerol-derived hepatic gluconeogenesis in adults with obesity without type 2 diabetes mellitus (T2DM) using oral carbon 13 (13 C)-labeled glycerol.Methods: A randomized, double-blind, placebo-controlled trial was performed in participants with magnetic resonance imaging assessment of body fat and measurement of glycerol-derived 13 C enrichment in plasma glucose by nuclear magnetic resonance spectroscopy following ingestion of [U-13 C3 ]glycerol. Participants were randomized to oral empagliflozin 10 mg once daily or placebo for 3 months. Glycerol-derived 13 C enrichment studies were repeated, and treatment differences in the mean percentage of 13 C glycerol enrichment in glucose were compared using mixed linear models.Results: Thirty-five participants completed the study. Empagliflozin increased glycerol-derived 13 C enrichment between baseline and follow-up by 6.5% (P = 0.005), consistent with less glycerol from visceral adipose tissue (VAT). No difference was found with placebo. Glycerol-derived 13 C enrichment was lower in participants with high VAT compared with low VAT by 12.6% (P = 0.04), but there was no heterogeneity of the treatment effect by baseline VAT. Glycerol-derived 13 C enrichment was inversely correlated with VAT but was not correlated with weight loss.Conclusions: VAT is associated with endogenous glycerol-derived hepatic gluconeogenesis, and empagliflozin reduces endogenous glycerol gluconeogenesis in adults with obesity without T2DM. These findings suggest a mechanism by which sodium-glucose cotransporter 2 inhibitors may prevent T2DM in obesity. [ABSTRACT FROM AUTHOR]

Objective: Lifestyle intervention remains the cornerstone of management of type 2 diabetes mellitus (T2DM). However, adherence to physical activity (PA) recommendations and the impact of that adherence on cardiorespiratory fitness in this population have been poorly described. We sought to investigate adherence to PA recommendations and its association with cardiorespiratory fitness in a population of patients with T2DM.Research Design and Methods: A cross-sectional analysis of baseline data from a randomized clinical trial (NCT00424762) was performed. A total of 150 individuals with medically treated T2DM and atherosclerotic cardiovascular disease (ASCVD) or risk factors for ASCVD were recruited from outpatient clinics at a single academic medical center. All individuals underwent a graded maximal exercise treadmill test to exhaustion with breath-by-breath gas exchange analysis to determine VO2peak. PA was estimated using a structured 7-Day Physical Activity Recall interview.Results: Participants had a mean ± SD age of 54.9 ± 9.0 years; 41% were women, 40% were black, and 21% were Hispanic. The mean HbA1c was 7.7 ± 1.8% and the mean BMI, 34.5 ± 7.2 kg/m2. A total of 72% had hypertension, 73% had hyperlipidemia, and 35% had prevalent ASCVD. The mean ± SD reported daily PA was 34.3 ± 4 kcal/kg, only 7% above a sedentary state; 47% of the cohort failed to achieve the minimum recommended PA. Mean ± SD VO2peak was 27.4 ± 6.5 mL/kg fat-free mass/min (18.8 ± 5.0 mL/kg/min).Conclusions: On average, patients with T2DM who have or are at risk for ASCVD report low levels of PA and have low measured cardiopulmonary fitness. This underscores the importance of continued efforts to close this therapeutic gap. [ABSTRACT FROM AUTHOR]

Bloodstream infections (BSIs) are common in patients with continuous-flow left ventricular assist devices (CF-LVADs). Whether CF-LVADs modulate the febrile response to BSIs is unknown. We retrospectively compared the febrile response to BSIs in patients with heart failure (HF) with CF-LVADs versus a control population of patients with HF receiving inotropic infusions. BSIs were adjudicated using the Centers for Disease Control and Prevention and the National Healthcare Safety Network criteria. Febrile status (temperature ≥38°C, 100.4 °F), temperature at presentation with BSI, and the highest temperature within 72 hours (Tmax) were collected. We observed 59 BSIs in LVAD patients and 45 BSIs in controls. LVAD patients were more likely to be afebrile and to have a lower temperature at presentation than control (88% vs 58%, p=0.002, and 37°C ±0.7 vs 37.7°C ±1.0, p=0.0009, respectively). By 72 hours, the difference in afebrile status diminished (53% vs 44%, p=0.42), and the Tmax was similar between the LVAD and control groups (37.9°C±0.9 vs 38.2°C±0.8, respectively, p=0.10). In conclusion, at presentation with a BSI, the vast majority of CF-LVAD patients were afebrile, an event which occurred at a higher frequency when compared with patients with advanced HF on chronic inotropes via an indwelling venous catheter. These data alert clinicians to have a very low threshold to obtain blood cultures in CF-LVAD patients even in the absence of fever. Further study is needed to determine whether a delayed or diminished febrile response represents another pathophysiological consequence of CF-LVADs. [ABSTRACT FROM AUTHOR]

Background: Though the proportion of female Internal Medicine (IM) residents and faculty has increased, there is minimal large scale modern data comparing resident performance by gender. This study sought to examine the effects of resident and faculty gender on resident evaluations. Methods: Retrospective observational study over 5 years in a single IM program. IM certifying examination pass rates were obtained from the American Board of IM. Results: Four hundred eighty-eight residents (195 women, 293 men), evaluated by 430 attending physicians (163 women, 270 men) were included. Twelve thousand six hundred eighty-one evaluations between 2007 and 2012 were analyzed. Female residents scored higher in two domains (Medical Interviewing, and Interpersonal and Communication Skills) (p < 0.01 for each), with no significant difference between genders for the other domains (Medical Knowledge, Overall Patient Care, Physical Examination, Procedural Skills, Professionalism, Practice Based Learning and Improvement, System Based Practices and Overall score). There were no differences in scoring between female and male attending physicians. There were no differences in certifying examination scores between women and men among graduating residents. National pass rates for women were not statistically different to pass rates for men from 1987 to 2015. Conclusions: Data from one large academic medical center demonstrate higher ratings for female residents on performance domains reflecting bedside care and interpersonal skills, with similar scores for medical knowledge and remaining domains. No significant difference was seen locally in certifying examination scores, nor in recent national pass rates, an objective measure of medical knowledge. Despite imbalanced female representation in areas of medicine, our data suggest that gender-based disparities in Internal Medicine resident medical knowledge and physician competency are no longer present. [ABSTRACT FROM AUTHOR]

Context While the prevalence of vitamin D deficiency is well described in various populations, limited data are available regarding longitudinal variation in serum 25-hydroxyvitamin D concentrations. Objectives To evaluate the temporal trends in serum 25( OH)D, prevalence of vitamin D deficiency and factors influencing these trends. Participants, Design and Setting: Adults enrolled in the Dallas Heart Study, a longitudinal, probability-based, multiethnic, population study in Dallas, Texas, USA. Main Outcome Measures Prevalence of vitamin D deficiency and predictors of change in serum 25( OH)D. Results A total of 2045 participants had serum 25( OH)D measured on two occasions (2000-2002 and 2007-2009) at a median interval of 7 years. Serum 25( OH)D decreased (42.7-39.4 nmol/L, P<.001) and the prevalence of vitamin D deficiency [25( OH)D <50 nmol/L] increased significantly (60.6%-66.4%, P<.0001) despite vitamin D supplementation increasing over the interval (7.2%-23.0%; P<.0001). In a multivariable model adjusting for sex, race, BMI, age, season of blood draw, smoking and exercise, a greater decline in serum 25( OH)D was noted in men compared with women (−8.0 vs −3.5 nmol/L, P<.0001), in participants of Hispanic ethnicity vs White and Black ethnicity ( P<.0001), in nonobese vs obese participants (−7.2 vs −4.0 nmol/L, P=.005) and in nonusers vs users of vitamin D supplements (−5.7 vs −1.7 nmol/L, P=.032). Conclusions Despite increased vitamin D supplementation, serum 25( OH)D decreased in an ethnically diverse cohort of Dallas County residents between 2000-2002 and 2007-2009. Features most predictive of a decline in serum 25( OH)D include male sex, Hispanic ethnicity and weight gain. [ABSTRACT FROM AUTHOR]

Right-sided heart failure is the most common cause of death in pulmonary hypertension (PH). Echocardiographic measurements of right atrial (RA) size are associated with worse outcome in PH, however the association between RA function and death in PH has not been well-described. 160 PH patients (World Health Organization groups 1-5) underwent cardiac magnetic resonance imaging (cMRI) and right heart catheterization (RHC) within 6 weeks of each other at a tertiary care academic medical center in the United States. We measured cMRI RA maximum and minimum volumes indexed to body surface area and calculated RA emptying fraction (RAEF). We evaluated the relationship between RAEF and clinical variables with death using Cox proportional hazard models. 57 deaths occurred during a median follow-up of 3.5 years (36 % died overall, 10 % per year). RAEF was directly correlated in univariate analyses with right ventricular (RV) ejection fraction, left ventricular (LV) ejection fraction, LV size, cardiac index, absence of tricuspid and pulmonic regurgitation, absence of pericardial effusion, estimated glomerular filtration rate, 6-minute walk distance, and pulmonary arterial oxygen saturation, whereas it was inversely correlated with death, BNP, heart rate, mean RA pressure, mean PA pressure, pulmonary and systemic vascular resistance, RV size, and RA size. Using multivariate analyses, RAEF had a robust inverse association with death after adjusting for measured risk factors (HR per 5 % change in RAEF: 0.83 [95 % CI 0.73-0.94], p = 0.003). In PH patients, decreased RAEF by cMRI is independently associated with worse survival after adjustment for other risk factors. [ABSTRACT FROM AUTHOR]

Objective: To assess the impact of intermediate-term treatment with rosiglitazone on high-sensitivity cardiac troponin T levels among patients with type 2 diabetes mellitus with or at high risk of coronary artery disease. Methods: High-sensitivity cardiac troponin T level was measured at baseline and after 6 months of study treatment in a randomized trial comparing rosiglitazone versus placebo in patients with type 2 diabetes and prevalent cardiovascular disease or multiple cardiovascular disease risk factors. Univariable and multivariable linear regression analyses were performed to assess the effect of rosiglitazone versus placebo on high-sensitivity cardiac troponin T levels. Results: The study included 150 randomized participants, of whom 106 had paired baseline and end-of-study blood samples for analysis (mean age: 56 ± 8 years, 42% women; 8.8 years average type 2 diabetes duration; mean haemoglobin A1c of 7.5). Almost all study participants (93%) had detectable high-sensitivity cardiac troponin T (⩾3 ng/L) at baseline, including 23% with high-sensitivity cardiac troponin T levels exceeding the threshold commonly used to diagnose myocardial infarction (⩾14 ng/L). Change in high-sensitivity cardiac troponin T levels from baseline to follow-up was not significantly different between rosiglitazone and placebo groups (p = 0.316). Conclusion: Rosiglitazone did not impact high-sensitivity cardiac troponin T levels, adding to the growing body of literature suggesting that the incremental heart failure risk associated with rosiglitazone is not mediated by direct myocardial injury. [ABSTRACT FROM AUTHOR]

Sedentary behavior is an adverse health risk factor that is independent of physical activity. The relationship between sedentary behavior, exercise activity and the ankle-brachial index (ABI) is not well understood. We analyzed data from the National Health and Nutrition Examination Survey (NHANES) 2003–2004. Accelerometer data were used to quantify exercise and sedentary time for each participant. A low ABI was defined as a value <1.0 (including borderline values). Multi-variable adjusted logistic regression analyses were performed with sedentary and exercise times as independent variables, adjusting for important confounders. There were 1443 asymptomatic participants (mean age 61 years, 49% female, 55% current/prior smokers) with mean daily sedentary and exercise times of 454±144 and 18±20 minutes, respectively. Of the participants, 23% had an ABI <1.0 (8.7% with ABI <0.9). Sedentary time was positively associated with a low ABI (odds ratio [OR] 1.22 per 1 standard deviation [SD], [95% confidence interval (CI), 1.03–1.43]; p=0.02) while exercise time was inversely associated with a low ABI (OR 0.71 per 1 SD, [95% CI, 0.57–0.89]; p=0.003). Sedentary time is associated with low ABI values in the asymptomatic population. This association appears to be independent of exercise time and warrants further investigation. [ABSTRACT FROM AUTHOR]

OBJECTIVE To evaluate the impact of exercise training (ET) on metabolic parameters among participants with type 2 diabetes mellitus (T2DM) who do not improve their cardiorespiratory fitness (CRF) with training. RESEARCH DESIGN AND METHODS We studied participants with T2DMparticipating in the Health Benefits of Aerobic and Resistance Training in Individuals With Type 2 Diabetes (HART-D) trial who were randomized to a control group or one of three supervised ET groups for 9 months. Fitness response to ET was defined as a change in measured peak absolute oxygen uptake (ΔVO2peak, in liters perminute) from baseline to follow-up. ET participants were classified based on ΔVO2peak into fitness responders (ΔVO2peak ≥5%) and nonresponders (ΔVO2peak <5%), and changes in metabolic pro les were compared across control, fitness responder, and fitness nonresponder groups. RESULTS A total of 202 participants (mean age 57.1 ± 7.9 years, 63% women) were included. Among the exercise groups (n = 161), there was substantial heterogeneity in ΔVO2peak; 57% had some improvement in CRF (ΔVO2peak >0), with only 36.6% having a ≥5% increase in VO2peak. Both fitness responders and nonresponders (respectively) had significant improvements in hemoglobin A1c and measures of adiposity (ΔHbA1c: -0.26% [95%CI - 0.5 to -0.01] and -0.26% [-0.45 to -0.08]; Δwaist circumference: -2.6 cm [-3.7 to -1.5] and -1.8 cm [-2.6 to -1.0]; Δbody fat: -1.07% [-1.5 to -0.62] and -0.75% [-1.09 to -0.41]). No significant differences were observed in the degree of change of these metabolic parameters between fitness responders and nonresponders. Control group participants had no significant changes in any of these metabolic parameters. CONCLUSIONS ET is associated with significant improvements in metabolic parameters irrespective of improvement in cardiorespiratory fitness. [ABSTRACT FROM AUTHOR]

More than 1 in 10 US adolescents have prediabetes or diabetes, and elevated glycosylated haemoglobin (HbA1C) in youth is associated with increased risk of death before the age of 55 years. We conducted a prospective, cross-sectional study of 31,546 consecutive volunteer blood donors, 16–19 years of age, who donated blood during school blood drives between 1 September 2011 and 21 December 2012 in Texas. In the overall cohort, the prevalence of elevated HbA1C was 11.5%, including 11.0% in the prediabetes range (HbA1C 5.7%–6.4%) and 0.5% in the diabetes range (HbA1C ⩾ 6.5%). The prevalence of elevated HbA1C was higher in boys compared with girls (15.7% vs 7.9%, p < 0.001) and was especially high in racial/ethnic minorities (Blacks 32.7%, Asians 19.7%, Hispanics 13.1%) compared with Whites (8.0%, p < 0.001). There was a significant increase in total cholesterol and blood pressure across categories of increasing HbA1C in the overall cohort and stratified by sex and race/ethnicity. Blood donation programmes can serve as unique portals for health screening with potential for intervention in adolescents. [ABSTRACT FROM AUTHOR]

Background Some cardiac transplant programs may upgrade listed patients to United Network for Organ Sharing ( UNOS) 1A-status during the holidays. Whether more transplants actually occur during holidays is unknown. Methods We assessed rates of single-organ heart transplantation from 2001 to 2010 for recipients age ≥18 yr using the UNOS database. Patients were stratified by transplantation during holiday (±3 d, n = 2375) and non-holiday periods (n = 16 112). Holidays included Easter/Spring break, Memorial Day, July 4th, Labor Day, Thanksgiving, and Christmas/New Years (winter holidays). Secondary analysis assessing transplant rates across seasons was also completed. Results Donor and recipient characteristics were similar between groups. Compared with non-holidays, July 4th had higher transplant rates (5.69 vs. 5.09 transplants/d, p = 0.03) while the winter holiday had lower transplant rates (4.50 vs. 5.09 transplants/d, p < 0.01). There was a trend toward lower transplant rates for all holidays compared with non-holidays (p = 0.06). Transplant rates were significantly different across seasons with greater rates in spring and summer (p < 0.01). Conclusion Heart transplant rates were higher during the July 4th and lower during the winter holidays. Although there was a higher likelihood of transplantation during the spring and summer seasons, upgrading patients to 1A status during most holidays may not improve their chances for transplantation. [ABSTRACT FROM AUTHOR]

Sirolimus is used in cardiac transplant recipients to prevent rejection, progression of cardiac allograft vasculopathy, and renal dysfunction. However, sirolimus has many potential side effects and its tolerability when used outside of clinical trials is not well established. We describe a decade of experience with sirolimus in cardiac transplant recipients at our institution. We retrospectively reviewed records of all adult cardiac transplant recipients living between September 1999 and February 2010 (n = 329) and identified 67 patients (20%) who received sirolimus. The indications for sirolimus were cardiac allograft vasculopathy (67%), renal dysfunction (25%), rejection (4%), and intolerability of tacrolimus (3%). One-third of patients discontinued sirolimus at a median (25th, 75th percentiles) of 0.9 (0.2, 1.6) yr of duration. Over 70% of subjects experienced an adverse event attributed to sirolimus. Adverse events were associated with higher average sirolimus levels (9.1 ng/mL vs. 7.1 ng/mL, p = 0.004). We conclude that sirolimus is frequently used in cardiac transplant recipients (20%) and commonly causes side effects, often necessitating discontinuation. Higher average sirolimus levels were associated with adverse events, suggesting that tolerability may improve if levels are maintained within the lower end of the current therapeutic range; however, the improvement in tolerability would need to be balanced with the potential for decreased efficacy. [ABSTRACT FROM AUTHOR]

Objective: Visceral (VAT) and abdominal subcutaneous (SAT) adipose tissues contribute to obesity but may have different metabolic and atherosclerosis risk profiles. We sought to determine the associations of abdominal VAT and SAT mass with markers of cardiac and metabolic risk in a large, multiethnic, population-based cohort of obese adults. Design and Methods: Among obese participants in the Dallas Heart Study, we examined the cross-sectional associations of abdominal VAT and SAT mass, assessed by magnetic resonance imaging (MRI) and indexed to body surface area (BSA), with circulating biomarkers of insulin resistance, dyslipidemia, and inflammation ( n = 942); and with aortic plaque and liver fat by MRI and coronary calcium by computed tomography ( n = 1200). Associations of VAT/BSA and SAT/BSA were examined after adjustment for age, sex, race, menopause, and body mass index. Results: In multivariable models, VAT significantly associated with the homeostasis model assessment of insulin resistance (HOMA-IR), lower adiponectin, smaller LDL and HDL particle size, larger VLDL size, and increased LDL and VLDL particle number ( p < 0.001 for each). VAT also associated with prevalent diabetes, metabolic syndrome, hepatic steatosis, and aortic plaque ( p < 0.001 for each). VAT independently associated with C-reactive protein but not with any other inflammatory biomarkers tested. In contrast, SAT associated with leptin and inflammatory biomarkers, but not with dyslipidemia or atherosclerosis. Associations between SAT and HOMA-IR were significant in univariable analyses but attenuated after multivariable adjustment. Conclusion: VAT associated with an adverse metabolic, dyslipidemic, and atherogenic obesity phenotype. In contrast, SAT demonstrated a more benign phenotype, characterized by modest associations with inflammatory biomarkers and leptin, but no independent association with dyslipidemia, insulin resistance, or atherosclerosis in obese individuals. These findings suggest that abdominal fat distribution defines distinct obesity sub-phenotypes with heterogeneous metabolic and atherosclerosis risk. [ABSTRACT FROM AUTHOR]

Background We compared cardiovascular (CV) risk factors (CVRFs) of community-based participatory research (CBPR) participants with the community population to better understand how CBPR participants relate to the population as a whole. Methods GoodNEWS participants in 20 African-American churches in Dallas, Texas were compared with age/sex-matched African-Americans in the Dallas Heart Study (DHS), a probability-based sample of Dallas County residents. DHS characteristics were sample-weight adjusted to represent the Dallas County population. Results Despite having more education (college education: 75 versus 51%, P< 0.0001), GoodNEWS participants were more obese (mean body mass index: 34 versus 31 kg/m2, P< 0.001) and had more diabetes (23 versus 12%, P< 0.001) and hyperlipidemia (53 versus 14%, P< 0.001) compared with African-Americans in Dallas County. GoodNEWS participants had higher rates of treatment and control of most CVRFs (treated hyperlipidemia: 95 versus 64%, P< 0.001; controlled diabetes: 95 versus 21%, P< 0.001; controlled hypertension: 70 versus 52%, P= 0.003), were more physically active (233 versus 177 metabolic equivalent units-min/week, P< 0.0001) and less likely to smoke (10 versus 30%, P< 0.001). Conclusions Compared with African-Americans in Dallas County, CBPR participants in church congregations were more educated, physically active and had more treatment and control of most CVRFs. Surprisingly, this motivated population had a greater obesity burden, identifying them as a prime target for CBPR-focused obesity treatment. [ABSTRACT FROM PUBLISHER]