Handgrip and sex-specific cardiometabolic risk factors in Hispanic/Latino migrant farmworkers.

Studies have suggested that handgrip strength might be a marker for cardiometabolic risk (CMR), but it has not been studied in Hispanic/Latino farmworker population. This study aimed to characterize absolute and relative handgrip strength in Hispanic/Latino farmworkers, and investigate the sex-specific association between handgrip strength and CMR factors. CMR factors and seated isometric absolute (the sum of both hands) and relative (absolute handgrip strength divided by body mass index) handgrip strengths were collected in 173 Hispanic/Latino farmworkers (mean age 35.1 ± 0.7 years; 49% female). The absolute and the relative handgrip strengths were 89.2 ± 1.8 kg, 3.3 ± 0.1 kg among males, and 56.5 ± 1.9 kg, 1.9 ± 0.1 kg among females, respectively. Age was correlated with absolute (r = - 0.17, p = 0.03) and relative handgrip strengths (r = - 0.28, p < 0.01). In males, absolute handgrip was related to triglycerides (r = - 0.25, p < 0.05), whereas relative handgrip was related to waist circumference (r = - 0.32, p < 0.01), waist/hip circumference ratio (r = - 0.36, p < 0.01), high-density lipoprotein (r = 0.24, p < 0.05), and triglycerides (r = - 0.35, p < 0.01). In females, absolute handgrip was related to fasting plasma glucose (r = - 0.28, p = 0.03), whereas relative handgrip was related to waist circumference (r = - 0.38, p < 0.01) and fasting plasma glucose (r = - 0.22, p < 0.05). Males had lower absolute handgrip strength when their triglycerides levels were at risk (p = 0.021), and lower relative handgrip strength when their plasma glucose (p = 0.034) and triglycerides (p = 0.002) levels were at risk. Females had lower relative handgrip strength when their plasma glucose (p = 0.001) and blood pressure (p = 0.004) were at risk. This study suggests that handgrip strength may be associated with sex-specific CMR factors in a Hispanic/Latino farmworker population.

Polypectomy versus surgery in early colon cancer: size and location of colon cancer affect long-term survival.

BACKGROUND AND AIMS: The colon cancer survival rate is significantly affected by location, stage, and size of the cancer. Polypectomy was shown be as equally effective as surgery in early-stage colon cancer, but there have been no established clinical guidelines in the management of colon cancer based on the size of the polyp or the tumor location. The aim of our study was to assess the early-stage colon cancer-specific survival rate in patients who underwent endoscopic polypectomy versus surgery, based on size and location of tumor in early-stage colon cancer. METHODS: This is a population-based nationwide study in the USA. RESULTS: Of 13,157 patients, 15.5% underwent endoscopic treatment and 84.5% underwent surgical therapy. For early cancer tumors located in the left colon, polypectomy yielded comparable 5-year survivals to surgery irrespective of size of the tumors. Five-year early cancer-specific survivals were similar for tumors located in the right colon that were < 20 mm in size (94.5 vs 94.3%, p value = 0.94). However, tumors > 20 mm in size that were located in the right colon had better survivals when treated surgically compared to those treated with polypectomy (20-39 mm: 91.8 vs 74.2%; ≥ 40 mm: 92.4 vs 60%, both p values < 0.01). Similar results were obtained on propensity score analysis. CONCLUSIONS: Polypectomy was as effective as surgical therapy for small tumors. For larger tumors, surgical therapy is better than polypectomy for right-sided tumors, but both are equally effective for left-sided tumors.

Dose responses of vitamin D3 supplementation on arterial stiffness in overweight African Americans with vitamin D deficiency: A placebo controlled randomized trial.

BACKGROUND: Clinical trials are scant and equivocal on whether vitamin D can ameliorate arterial stiffness, particularly in populations at high risk for vitamin D deficiency and cardiovascular disease (CVD). This study determined the dose-response effects of vitamin D3 supplementation on arterial stiffness in overweight African Americans with vitamin D deficiency. METHODS: Seventy overweight African Americans (aged 13-45 years) with serum 25-hydroxyvitamin D [25(OH)D] levels ≤ 20 ng/mL were randomized to monthly oral supplementation of 18,000 IU (~600 IU/day, n = 17), 60,000 IU (~2000 IU/day, n = 18), or 120,000 IU (~4000 IU/day, n = 18) of vitamin D3 or placebo (n = 17) for 16-weeks. The arterial stiffness measurements, carotid-femoral pulse wave velocity (PWV) and carotid-radial PWV, were assessed by applanation tonometry at baseline and 16 weeks. RESULTS: Vitamin D3 supplementation demonstrated a dose-response increase in serum 25(OH)D concentrations between groups (P<0.01). A significant downward linear trend was observed for carotid-femoral PWV (P<0.01), as the mean changes in carotid-femoral PWV across the four treatment groups were 0.13 m/s (95% CI: -0.24, 0.51 m/s) for placebo, 0.02 m/s (95% CI: -0.34, 0.38 m/s) for 600 IU/day group, -0.11 m/s (95% CI: -0.50, 0.27 m/s) for the 2,000 IU/day group, and -0.70 m/s (95% CI: -1.07, -0.32 m/s) for the 4,000 IU/day group. Findings were similar for carotid-radial PWV (P = 0.03), as the mean changes in carotid-radial PWV across the four treatment groups were 0.24 m/s (95% CI: -0.45, 0.92 m/s) for placebo, 0.09 m/s (95% CI: -0.54, 0.73 m/s) for 600 IU/day group, -0.57 m/s (95% CI: -1.20, 0.07 m/s) for the 2,000 IU/day group, and -0.61 m/s (95% CI: -1.25, 0.02 m/s) for the 4,000 IU/day group. CONCLUSION: Arterial stiffness was improved by vitamin D3 supplementation in a dose-response manner in overweight African Americans with vitamin D deficiency.

Correction: Race/Ethnicity-Specific Association of Vitamin D and Global DNA Methylation: Cross-Sectional and Interventional Findings.

[This corrects the article DOI: 10.1371/journal.pone.0152849.].

Early Esophageal Cancer Specific Survival Is Unaffected by Anatomical Location of Tumor: A Population-Based Study.

Background. Approximately one-fifth of all esophageal cancer cases are defined as early esophageal cancer (EEC). Although endoscopic therapy (ET) has been shown to be equally effective as esophagectomy (EST) in patients with EEC, there is little information comparing the survival outcomes of the two therapies based on anatomical location. Methods. A population-based study was conducted and the data was obtained from Surveillance, Epidemiology, and End Results program. Patients with EEC (i.e., stages Tis and T1a) and treated with either ET or EST were analyzed to compare EEC-related survival for three different locations of tumor. Results. The overall EEC-specific 1-year and 5-year mean (±SE) survival rates were 11.66 ± 0.05 and 52.80 ± 0.58 months, respectively. Tumors located in lower third had better 5-year survival compared to those located in middle third (83.50% versus 73.10%, p < 0.01). However, when adjusted for age, race, gender, marital status, grade, stage of tumor, histological type, and treatment modality, there was no significant difference. Conclusion. The EEC-specific 1-year or 5-year adjusted survival did not differ by anatomic location of the tumor. Therefore, ET might serve as a minimally invasive yet effective alternative to EST to treat EEC.

Race/Ethnicity-Specific Association of Vitamin D and Global DNA Methylation: Cross-Sectional and Interventional Findings.

OBJECTIVES: Understanding of the influence of vitamin D deficiency on epigenome will provide novel insights into the chronic disease risk. We tested our hypotheses that 1) vitamin D deficiency is associated with global hypomethylation and this association may be race/ethnicity dependent; and 2) vitamin D supplementation will increase global DNA methylation level. METHODS: A two-stage design, cross-sectional observation followed by a 16 week randomized, double- blinded, placebo-controlled trial (RCT) of vitamin D3 supplementation, was undertaken. Global DNA methylation level (percentage of 5-methylcytosine, %5-mC) was quantified using leukocyte DNA with the MethylFlashTM Methylated DNA Quantification kit (Epigentek). Global methylation data was obtained from 454 Caucasians and African Americans (42%) in the observation cohort and 58 African Americans with vitamin D deficiency in the dose responsive RCT. RESULTS: In the cross-sectional study, African Americans had lower %5-mC than Caucasians (P = 0.04). A significant interaction was detected between plasma 25(OH)D and race on %5-mC (P = 0.05), as a positive association was observed between plasma 25(OH)D and %5-mC in African Americans (ß = 0.20, p<0.01), but not in Caucasians (ß = 0.03, p = 0.62). In the 16-week RCT, a dose-response benefit of vitamin D3 supplementation was observed for %5-mC, as indicated by a significant linear upward trend (-0.01 ± 0.01%, placebo; 0.11 ± 0.01%, ~600 IU/day; 0.30 ± 0.01%, ~2,000 IU/day; and 0.65 ± 0.01%, ~4,000 IU/day group; P-trend = 0.04). CONCLUSIONS: Vitamin D deficiency is associated with global hypomethylation in African Americans. Vitamin D3 supplementation increases global DNA methylation in a dose-response manner in African Americans with vitamin D deficiency.

Dose and time responses of vitamin D biomarkers to monthly vitamin D3 supplementation in overweight/obese African Americans with suboptimal vitamin d status: a placebo controlled randomized clinical trial.

BACKGROUND: A critical need exists to better understand the physiological sequel of vitamin D supplementation in obese individuals and African Americans. The aim was to comprehensively evaluate dose- and time-responses of a panel of vitamin D biomarkers to vitamin D supplements in this population. METHODS: We conducted a 16-week randomized, double-blinded, and placebo-controlled clinical trial. Seventy overweight/obese African Americans (age 13-45 years, 84 % females) with 25-hydroxyvitamin D [25(OH)D] concentrations ≤20 ng/mL were randomly assigned to receive a supervised monthly oral vitamin D3 of 18,000 IU (~600 IU/day, n = 17), 60,000 IU (~2000 IU/day, n = 18), 120,000 IU (~4000 IU/day, n = 18), or placebo (n = 17). RESULTS: There were significant dose- and time-responses of circulating 25(OH)D, 1,25-dihydroxyvitamin D [1,25(OH)2D], and intact parathyroid hormone (iPTH), but not fibroblast growth factor-23 (FGF-23), phosphorus and urine calcium to the vitamin D supplements. The mean 25(OH)D concentrations in the 2000 IU and 4000 IU groups reached ≥30 ng/mL as early as 8-weeks and remained at similar level at 16-weeks. The increase of 25(OH)D was significantly higher in the 4000 IU group than all the other groups at 8-weeks. The increase of 1,25(OH)2D was significantly higher in the 2000 IU and 4000 IU groups than the placebo at 8-weeks. Only the 4000 IU compared to the placebo significantly reduced iPTH at 8- and 16-weeks. CONCLUSIONS: Our RCT, for the first time, comprehensively evaluated time- and dose- responses of vitamin D supplementation in overweight/obese African Americans with suboptimal vitamin D status. Circulating 25(OH)D, 1,25(OH)2D, and iPTH, but not FGF-23, phosphorus and urine calcium, respond to vitamin D supplementation in a time- and dose-response manner. By monthly dosing, 2000 IU appears to be sufficient in achieving a 25(OH)D level of 30 ng/mL in this population. However, importantly, 4000 IU, rather than 2000 IU, seems to suppress iPTH. If replicated, these data might be informative in optimizing vitamin D status and providing individualized dosing recommendation in overweight/obese African Americans. TRIAL REGISTRATION: ClinicalTrials.gov number: NCT01583621, Registered on April 3, 2012.

Dietary sodium, adiposity, and inflammation in healthy adolescents.

OBJECTIVES: To determine the relationships of sodium intake with adiposity and inflammation in healthy adolescents. METHODS: A cross-sectional study involved 766 healthy white and African American adolescents aged 14 to 18 years. Dietary sodium intake was estimated by 7-day 24-hour dietary recall. Percent body fat was measured by dual-energy x-ray absorptiometry. Subcutaneous abdominal adipose tissue and visceral adipose tissue were assessed using magnetic resonance imaging. Fasting blood samples were measured for leptin, adiponectin, C-reactive protein, tumor necrosis factor-α, and intercellular adhesion molecule-1. RESULTS: The average sodium intake was 3280 mg/day. Ninety-seven percent of our adolescents exceeded the American Heart Association recommendation for sodium intake. Multiple linear regressions revealed that dietary sodium intake was independently associated with body weight (ß = 0.23), BMI (ß = 0.23), waist circumference (ß = 0.23), percent body fat (ß = 0.17), fat mass (ß = 0.23), subcutaneous abdominal adipose tissue (ß = 0.25), leptin (ß = 0.20), and tumor necrosis factor-α (ß = 0.61; all Ps < .05). No relation was found between dietary sodium intake and visceral adipose tissue, skinfold thickness, adiponectin, C-reactive protein, or intercellular adhesion molecule-1. All the significant associations persisted after correction for multiple testing (all false discovery rates < 0.05). CONCLUSIONS: The mean sodium consumption of our adolescents is as high as that of adults and more than twice the daily intake recommended by the American Heart Association. High sodium intake is positively associated with adiposity and inflammation independent of total energy intake and sugar-sweetened soft drink consumption.

Epithelial sodium channel inhibition by amiloride on blood pressure and cardiovascular disease risk in young prehypertensives.

Overactivity of the epithelial sodium channel (ENaC) is considered to be one mechanism underlying obesity-related blood pressure (BP) elevation. In an open-labeled, nonplacebo-controlled clinical trial (Clinicaltrials.gov: NCT-01308983), the authors aimed to comprehensively evaluate the effects of amiloride monotherapy, an ENaC blocker, on BP and cardiovascular risk in young adults with prehypertension (n=17). The mean body mass index of participants was 28.45±1.30 kg/m(2) . Following 10 mg daily amiloride for 4 weeks, peripheral systolic BP (SBP), central SBP, and carotid-radial pulse wave velocity were significantly reduced by -7.06±2.25 mm Hg, -7.68±2.56 mm Hg, and -0.72±0.33 m/s, respectively, whereas flow-mediated dilation was significantly increased by 2.2±0.9%. Following amiloride monotherapy for 4 weeks, a significant increase in serum aldosterone was observed (5.85±2.45 ng/dL). ENaC inhibition by amiloride may be used as an early intervention to halt the progression to full hypertension and cardiovascular disease in young adults with prehypertension.

Urinary prostasin excretion is associated with adiposity in nonhypertensive African-American adolescents.

BACKGROUND: Metabolic abnormalities in obesity can overstimulate the renal epithelial sodium channel (ENaC) and subsequently lead to blood pressure (BP) elevation. Prostasin, a membrane-bound/secretive serine protease, is thought to activate ENaC via the proteolytic cleavage of the channel. Our specific aim was to explore whether there is a relationship between adiposity and urinary prostasin excretion at the population level. METHODS: In 271 African-American adolescents, urinary prostasin concentrations were determined by enzyme-linked immunosorbent assay and normalized by urinary creatinine. RESULTS: Urinary prostasin excretion increased in the overweight/obese group (n = 110, 38.2 ± 4.0 ng/mg) vs. the normal-weight group (n = 161, 20.7 ± 1.2 ng/mg, P = 0.03). Urinary prostasin excretion was significantly correlated with BMI percentiles (r = 0.14, P = 0.02), waist circumference (r = 0.13, P = 0.05), total body fat mass (r = 0.20, P < 0.01), and percentage body fat (r = 0.23, P < 0.01). Urinary prostasin excretion was also correlated with plasma aldosterone (r = 0.11, P = 0.05) and systolic BP (SBP; r = 0.15, P = 0.02), but the significances disappeared after adjustment of any of the adiposity variables. CONCLUSION: Our data for the first time suggest that adiposity plays a role in urinary prostasin excretion, and its associations with aldosterone and BP appear to be modulated by adiposity. Whether urinary prostasin excretion is a biomarker/mechanism underlying obesity-related hypertension deserves further investigations.

Cytokine profiling of young overweight and obese female African American adults with prediabetes.

Approximately 5-10% of subjects with prediabetes become diabetic every year. Inflammation is involved in the development of obesity-related type 2 diabetes (T2D). However, to date, the relationship between inflammation and prediabetes, defined by hemoglobin A1c (HbA1c) ≥5.7 and <6.5%, remains largely unexplored, especially in African Americans. Therefore, in this study we examined a comprehensive panel of 13 cytokines involved in the inflammatory response in overweight/obese subjects with prediabetes. A total of 21 otherwise healthy, overweight/obese, young adult African American females with prediabetes, together with 20 matched overweight/obese controls, were selected for this study. Plasma cytokines were assessed by multiplex cytokine profiling. Plasma concentrations of interleukin (IL)-5, IL-6, IL-7, tumor necrosis factor-α (TNF-α), and granulocyte-monocyte colony-stimulating factor (GM-CSF) were significantly higher in the prediabetic group, as compared to the control group (all p<0.05). Plasma concentrations of all the other cytokines, interferon-γ (IFN-γ), IL-1ß, IL-2, IL-4, IL-8, IL-10, IL-12p70 and IL-13, seemed to be elevated in the prediabetic group, but failed to reach statistical significances. Upon merging both groups, HbA1c was found to be positively correlated with IFN-γ, IL-1ß, IL-2, IL-5, IL-7, IL-8, TNF-α and GM-CSF. This study demonstrates elevated levels of various pro-inflammatory cytokines in overweight/obese young subjects with prediabetes, which place them at higher risk of developing T2D and cardiovascular diseases. Our data also call for further investigations in animal models and population cohorts to establish the roles of a variety of pro-inflammatory cytokines in the early development of obesity-related T2D.

Plasma kallistatin is associated with adiposity and cardiometabolic risk in apparently healthy African American adolescents.

OBJECTIVE: It is generally recognized that obesity and cardiometabolic risk are more prevalent in African Americans. Kallistatin, a novel tissue kallikrein inhibitor, has anti-inflammatory and anti-oxidant properties. Thus, the goal of this study was to examine the relationships among plasma kallistatin levels, adiposity and cardiometabolic risk factors in African American adolescents. MATERIALS/METHODS: Plasma kallistatin levels were determined in 318 apparently healthy African American adolescents (aged 14-19 years, 48.1% females) by enzyme-linked immunosorbent assay. RESULTS: Plasma kallistatin levels did not differ between males (27.9±11.2 µg/mL) and females (26.8±11.0 µg/mL) (p=0.47). Plasma kallistatin levels were inversely correlated with percent body fat (% BF, r=-0.13, p=0.04), total cholesterol (r=-0.28, p<0.01), low density lipoprotein cholesterol (LDL, r=-0.30, p<0.01) and interleukin-6 (r=-0.14, p=0.05), but positively correlated with adiponectin (r=0.16, p=0.03) and high density lipoprotein (HDL, r=0.17, p=0.02). These correlations remained significant after adjustment for age, sex and body mass index percentiles. Stepwise multiple linear regression analysis showed that LDL cholesterol alone explained 14.2% of the variance in kallistatin, while % BF and adiponectin explained an additional 3.6% and 2.8% of the variance, respectively. CONCLUSIONS: The present study demonstrates that plasma kallistatin levels are inversely associated with adiposity, adverse lipid profiles and inflammation in apparently healthy African American adolescents. As a potent antioxidant and anti-inflammation agent, kallistatin may also hold therapeutic promise in cardiometabolic disorders.

Adolescent fiber consumption is associated with visceral fat and inflammatory markers.

CONTEXT: The link between adolescent fiber consumption, inflammation, and body fat distribution has not been investigated. OBJECTIVE: This study investigated associations of dietary fiber intake with inflammatory-related biomarkers and robust measures of total and central adiposity in a sample of 559 adolescents aged 14-18 yr (49% female, 45% Black). METHODS: Fasting blood samples were measured for leptin, adiponectin, resistin, C-reactive protein, and fibrinogen. Diet was assessed with four to seven 24-h recalls, and physical activity was determined by accelerometry. Fat-free soft tissue mass and fat mass were measured by dual-energy x-ray absorptiometry. Visceral adipose tissue was assessed using magnetic resonance imaging. RESULTS: Multiple linear regression, adjusting for age, race, Tanner stage, fat-free soft tissue mass, energy intake, and physical activity, revealed that dietary fiber intake was inversely associated with fat mass and serum leptin in males (all P < 0.03) but not in females. In both genders, dietary fiber intake was negatively associated with visceral adipose tissue, plasma C-reactive protein, and plasma fibrinogen and positively associated with plasma adiponectin (all P < 0.05). No relations were found between dietary fiber intake and plasma resistin in either males or females. CONCLUSION: Our adolescent data suggest that greater consumption of dietary fiber is associated with lower visceral adiposity and multiple biomarkers implicated in inflammation.

Circulating 25-hydroxyvitamin D concentrations are correlated with cardiometabolic risk among American black and white adolescents living in a year-round sunny climate.

OBJECTIVE: Low vitamin D status is common among healthy black and white adolescents residing at southern U.S. latitudes with a year-round sunny climate. Thus we aimed to study the relationships between circulating 25-hydroxyvitamin D [25(OH)D] and cardiometabolic risk factors in this population. RESEARCH DESIGN AND METHODS: 25(OH)D concentrations were measured with liquid chromatography tandem mass spectroscopy in 701 girls and boys (14-18 years old, 54% blacks, 49% females). Cardiometabolic risk was indexed by adipokines, inflammatory markers, fasting glucose, homeostatic model assessment-insulin resistance (HOMA-IR), lipid profile, and blood pressure (BP). RESULTS: Controlling for age, sex, race, sexual maturation, season, physical activity, and percent body fat, 25(OH)D concentrations were significantly correlated with adiponectin (r = 0.06, P = 0.05), leptin (r = -0.32, P < 0.01), fibrinogen (r = -0.05, P = 0.03), glucose (r = -0.16, P = 0.02), HOMA-IR (r = -0.17, P < 0.01), HDL cholesterol (r = 0.14, P = 0.02), systolic BP (r = -0.10, P = 0.02), and diastolic BP (r = -0.21, P < 0.01). When 25(OH)D concentrations were stratified into increasing tertiles, there were significant linear upward trends for adiponectin (P = 0.01) and HDL cholesterol (P = 0.04), but significant linear down trends for glucose (P < 0.01), HOMA-IR (P < 0.01), and systolic BP (P < 0.01), after adjusting for the above covariates. CONCLUSIONS: Circulating 25(OH)D concentrations are associated with various adverse cardiometabolic risk factors, independent of adiposity. Clinical trials addressing the effects of vitamin D supplementation on cardiometabolic risk are warranted in adolescents irrespective of their geographical regions.