Effects of short-term sugary beverage consumption on glucose control and cardiovascular disease risk factors: A randomized controlled parallel-arm trial

OBJECTIVE

To determine differences in glucose control and cardiovascular disease risk factors following three weeks of added soda, 100% fruit juice, or water in apparently healthy, college-aged adults.

PARTICIPANTS

Thirty-six adults (18 males; 18 females) between the ages of 18 and 30 years of age.

METHODS

A 3-arm randomized controlled parallel-arm trial; at baseline and after three weeks consuming the assigned beverage, participants completed glucose control and cardiovascular disease risk factor assessments.

RESULTS

There were no significant differences between beverage conditions for glucose control or cardiovascular disease risk factors (ps > 0.05). There were no significant changes in caloric intake or differences in caloric intake between conditions, p = 0.17.

CONCLUSIONS

In healthy, young adults, under free-living conditions, short-term consumption of two commercially packaged servings of SBs did not lead to significant glucose control or cardiovascular disease risk factor changes, indicating potential compensation and/or resilience to negative short-term effects.

Maternal Peer Support Through a Caregroup Model Improves Complementary Feeding of Infants by Refugee Mothers in Post-Emergency Settlements in the West-Nile Region in Uganda

Objectives

Introduction: Infant complementary feeding in refugee settlements remains inadequate, amidst declining humanitarian aid. However, there is limited evidence for interventions to address these nutrition challenges in the refugee settlements. Objective: Examine the effects of peer-led integrated nutrition education on infant feeding by South Sudanese refugee mothers in the West-Nile region in Uganda.

Methods

A community-based randomized control study enrolled 390 pregnant mothers in the 3rd trimester as baseline for a peer-led nutrition education intervention using the caregroup model. Two groups (moms-only and moms & dads combined) comprised treatments with a control group. Higher scores on the Medical Outcomes Study (MOS) Social Support Index were used as a proxy for better maternal social support. Infant complementary feeding was assessed using the 2021 WHO guidelines. Multivariable logistic regression models determined effects of the interaction of maternal social support by group over time on infant feeding practices. The models were adjusted for maternal and infant confounders.

Results

Maternal age (mean ± SD) was 27.7 ± 5.1 years while the infant birthweight was 3.1 ± 0.5 kg. Higher maternal social support positively affected timely introduction of solid and semi-solid foods in moms-only (β = 0.11, p = .011) and moms & dads (β = 0.11, p = .001) groups. Positive intervention effects were noted on infant minimum dietary diversity for both the moms-only group (β = 0.06, p = .01) and the moms & dads group (β = 0.03, p = .001), but no effect was observed between maternal social support and infant minimum meal frequency. However, higher maternal social support in both moms-only and moms & dads groups influenced meeting the minimum acceptable diet (β = 0.07, p = .016 and β = 0.04, p = .026 respectively) and consumption of eggs and/or flesh foods (β = 0.11, p < .0001 and β = 0.05, p = .004).

Conclusions

A maternal peer support integrated nutrition education program improved complementary feeding of infants in post-emergency settlements. Enhanced maternal social support in nutrition-sensitive programs may benefit infants in post-emergency settlements in the West-Nile region in Uganda.

Funding Sources

A grant from the Nestlé Foundation for the Study of Problems of Nutrition in the World, Switzerland.

Body Composition Measures Associated With Postprandial Triglyceride Concentrations

Objectives

A large increase in triglyceride (TG) concentrations following a high-fat meal (i.e., postprandial lipemia) is an independent cardiovascular disease risk factor. However, little is known regarding individual factors that are associated with or determine postprandial triglycerides. We aimed to identify body composition measures that are associated with postprandial triglyceride concentrations following a high-fat meal.

Methods

We conducted a secondary analysis of data from 5 previously conducted studies in our laboratory, each utilizing identical methods. Postprandial TG were measured at baseline and 4 hours after a high-fat shake (73% fat; 9 kcal/kg). In addition to body mass index (BMI) and waist circumference (WC), body composition variables – relative body fat (BF%), relative muscle mass (MM%), and visceral adipose tissue (VAT) – were measured via bioelectrical impedance.

Results

Across 5 studies, complete data from 156 participants (age: 44.9 ± 21.0 years; sex: 83F/73M; BMI: 27.3 ± 5.5 kg/m²; fasting glucose: 98.6 ± 7.8 mg/dL; fasting TG: 94.6 ± 45.3 mg/dL; fasting total cholesterol: 170.8 ± 34.5 mg/dL) were compiled for this secondary analysis. Postprandial TG were correlated with age (r = 0.24, p = 0.003) but no difference between sexes was observed (p = 0.06). Significantly associated with 4-hr TG were BMI (r = 0.29, p < 0.0001), WC (r = 0.33, p < 0.0001), BF% (r = 0.23, p = 0.004), MM% (r = 0.23, p = 0.004), and VAT (r = 0.35, p < 0.0001). In a backward elimination regression (R² = 0.15), the variables most predictive of 4-hr TG were MM% (β = 0.21, p = 0.009), VAT (β = 0.25, p = 0.004), and BF% (β = 0.16, p = 0.064).

Conclusions

In a secondary analysis of 156 participants across 5 studies, we identified MM%, VAT, and BF% as being the most predictive of 4-hr TG. Although the strength of the relationship may be weak to moderate, body composition appears to influence postprandial triglycerides. Further research could determine preventative measures regarding body composition to lower the risk of cardiovascular disease associated with postprandial triglycerides.

Funding Sources

Oklahoma Center for the Advancement of Science and Technology (HR20-027), American Society for Nutrition, Donna Cadwalader Research and Development Grant, Oklahoma State University Office of the Vice President for Research.

Pulse Supplementation Improves Gut Health and Lowers Total Cholesterol in Postmenopausal Women

Objectives

Menopause is associated with many physiological changes as well as increased risk of obesity, cardiovascular disease, type 2 diabetes, and gut-related diseases (i.e. irritable bowel syndrome, inflammatory bowel disease, colon cancer). Data regarding the use of pulse crops in alleviating health risks associated with menopause are limited. This study investigated the effects of pulse supplementation on markers of gut health and metabolic outcomes in postmenopausal women.

Methods

Thirty-five postmenopausal (≥1 year without menstruation) women, ages 45–70 years old, who were not on hormone replacement therapy, probiotics, antibiotics, multiple supplements, or medications that affect lipids or glucose, were recruited for this clinical study. Study participants were asked to consume 100 g of pulses (alternate between chickpeas, kidney beans, pinto beans, black-eyed peas, and lentils) daily for 12 wks, and to maintain their normal diet and lifestyle. Anthropometric measures including body composition by dual-energy X-ray absorptiometry, plasma lipids and glucose, fecal short chain fatty acids (SCFAs), and stool characteristics (Bristol Stool Chart and the Cleveland Clinic Constipation Scoring System) were assessed before and at the end of 12-wk supplementation. P < 0.05 was considered statistically significant.

Results

There were no differences in anthropometric measures and plasma glucose at the end of the 12-wk supplementation compared to baseline. However, a reduction in plasma total cholesterol (p = 0.039) and LDL-C (p = 0.026), but an increase in both VLDL-C (p = 0.031) and triglycerides (p = 0.033) were observed with pulse supplementation. Constipation score significantly improved (p = 0.003) but no change in stool quality were observed with pulse supplementation. Fecal acetic acid (p< 0.001), n-butyric (p = 0.038), n-caproic (p = 0.004) and total SCFAs (p = 0.001) were also significantly increased with pulse supplementation.

Conclusions

Our findings demonstrate that 12 wks of pulse supplementation improved markers of gut health and lowers total- and LDL-cholesterol in postmenopausal women. This population who are at an increased risk for cardiovascular and gut-related diseases can benefit from regularly consuming pulses.

Funding Sources

USDA Award Pulse Crop Health Initiative (#58-3060-0-048) and the Jim and Lynn Williams Professorship

Children With Steatosis and Fibrosis Have a Blunted Postprandial FGF19 Response to a High-Fat Meal

Objectives

The standard for early screening of NAFLD in children is circulating liver enzymes, but those measures lack clinical specificity and sensitivity for NAFLD. As an alternative candidate, we tested the hypothesis that the postprandial fibroblast growth factor-19 (FGF19) response to an abbreviated fat tolerance test (AFTT) may discriminate pediatric patients with NAFLD from obese and normal weight peers.

Methods

In this cross-sectional study, 15 normal weight controls (6M/9F; age: 17 ± 2y; BMI: 49 ± 24%ile), 13 controls with obesity without NAFLD (5M/8F; age: 17 ± 2y; BMI: 98 ± 1%ile), and 9 patients with NAFLD (7M/2F; age: 15 ± 2y; BMI: 99 ± 0%ile) completed an AFTT. Following an overnight fast, participants consumed a high-fat meal (73% fat; 9 kcal/kg) and FGF19 was measured at baseline and 4h post-meal. Liver steatosis (controlled attenuation parameter (CAP)) and fibrosis (stiffness) were measured via Fibroscan.

Results

Two-way ANOVA revealed no group × time interaction, time effect, or group effect (p’s &gt; 0.05) for FGF19. Similarly, FGF19 tAUC and ΔFGF19 did not differ across groups (p's &gt; 0.05). There was a medium effect size between the OB control and NAFLD groups (d = 0.57) and the normal weight and NAFLD groups (d = 0.47) and a large effect size between the normal weight and NAFLD groups (d = 0.80) for 4h FGF19, suggesting that a larger sample size may reveal statistically lower values in children with NAFLD. Across all groups, fasting FGF19 was not different between children with high (≥ 220 dB/m) vs. low steatosis (≤ 220 dB/m; p = 0.09), however 4h FGF19 was 256% higher in children with lower steatosis (1406 ± 1371 pg/mL) compared to higher steatosis (394 ± 352 pg/mL; p = 0.007). Likewise, across all groups, fasting FGF19 did not differ between children with no fibrosis (kPa &lt; 6) and children with evidence of fibrosis (kPa &gt; 6; p = 0.11); however, children with no fibrosis had 4-fold higher 4h FGF19 compared to children with evidence of fibrosis (kPa &gt; 6; p = 0.04).

Conclusions

The postprandial rise in FGF19 was blunted in children with higher liver steatosis and fibrosis. A major role of FGF19 is to promote fatty acid oxidation and inhibit triglyceride synthesis in the liver, thus this finding provides insight on how hepatic fat accrues in pediatric NAFLD.

Funding Sources

Oklahoma Shared Clinical and Translational Resources (OSCTR); Barbara Pass Research Grant, Oklahoma State University.

Adverse Childhood Experiences and Obesity Linked to Indicators of Gut Permeability and Inflammation

Objectives

Gut permeability appears to increase cardiovascular disease risk by allowing bacterial components to enter the bloodstream, leading to low-grade inflammation. Emerging evidence suggests that psychosocial stress promotes gut permeability, but the effect of chronic stress induced by adverse childhood experiences (ACEs) on the gut barrier remains unclear. Moreover, the existence of an additive effect of psychological stressors and nutritional factors that increase gut permeability – such as obesity – is unknown. We aimed to: 1) investigate the effect of ACEs on gut permeability indices, and 2) examine whether high ACE status and obesity in combination have a greater, negative effect on indicators of gut permeability and inflammation than either alone.

Methods

Women (N = 79, aged 18–84 y) free of cardiometabolic diseases (other than obesity) and inflammatory conditions and not regularly taking anti-inflammatory medications were included in a 2 × 2 factorial design with ACE status (either 0 ACEs or 3 + ACEs) and body mass index (BMI) (either normal-weight [18.5–24.9 kg/m²; NW] or obesity [>30 kg/m²; OB]) as factors (n = 15–27/group). Fasting serum was obtained and markers of gut permeability (i.e., lipopolysaccharide [LPS] binding protein; fatty-acid binding protein-2 [FABP2]; anti-LPS core IgM; soluble CD14 (sCD14) and inflammation (i.e., C-reactive protein [CRP]; tumor necrosis factor [TNF]-α; interleukin [IL]-6) measured. Data were analyzed using 2-way ANCOVA (age-adjusted) with SPSS 26.

Results

LPS binding protein and FABP2 were higher in OB versus NW, regardless of ACE status (P_BMI ≤ 0.04). Higher ACE status was associated with increased circulating anti-LPS core IgM (P_ACE = 0.04), but BMI had no effect. sCD14 was unaffected by BMI or ACEs. CRP was elevated in OB vs. NW (P_BMI < 0.001) and tended to be higher with 3 + ACEs compared to 0 ACEs (P_ACE = 0.06). Moreover, TNF-α was greater in 3 + ACEs relative to 0 ACEs (P_ACE = 0.03). IL-6 was unaltered by BMI or ACE status. No interaction effects were observed for any marker of gut permeability or inflammation.

Conclusions

High ACE status and obesity were independently associated with evidence of gut permeability and inflammation, but no combination of BMI and ACE status affected these measures.

Funding Sources

NIA R36, NIGMS P20, NHLBI F31.

Wheat Germ Supplementation Improves Glucose Homeostasis Markers of Overweight Adults Independent of Gut Microbial Modulation

Objectives

This study investigated the effects of wheat germ (WG) supplementation on inflammation, metabolic, and gut health markers in overweight adults.

Methods

Forty overweight (BMI = 25.0–30 kg/m2) adults between 18–45 y old were recruited to this single-blinded randomized placebo-controlled study. Qualified participants were asked to maintain their normal diet and physical activity and consume energy balls containing 30 g of either WG or cornmeal (control) daily for 4 wks. Anthropometric and metabolic parameters, as well as dietary (3-d food record), medical history, physical activity (Yale Physical Activity Survey), stool measures (Bristol Stool Chart and the Cleveland Clinic Constipation Scoring System), gut integrity markers, and fecal bacterial population were assessed at baseline and at the end of the supplementation period.

Results

Thirty-nine participants completed the 4-week study (n = 20 and 19 for the WG and control group, respectively). There were no differences in the lipid profile, but glycated hemoglobin (P = 0.04), insulin (P = 0.03), and homeostatic model assessment of insulin resistance (HOMA-IR; P = 0.04) were significantly decreased in the WG but not the control group. Similarly, the adipokine resistin was also significantly reduced (P = 0.03) by WG but not the control. There were no changes in stool characteristics between the two groups before and after supplementation. Similarly, there were no changes in gut bacterial population due to WG supplementation but the phyla Bacteroidetes (P = 0.03) and Proteobacteria (P = 0.048) and the genus Bacteroides (P = 0.03) were significantly decreased in the control group. No significant changes were observed in plasma inflammatory markers, fecal short-chain fatty acid (SCFA) concentrations, and markers of gut integrity in both groups.

Conclusions

Four weeks of WG supplementation improved markers of glucose homeostasis, which can partly be attributed to the reduction of the pro-inflammatory adipokine resistin and not due to changes within the gut (i.e., bacterial population, gut integrity markers, and SCFA production). Our findings indicate that WG may be a safe, effective, and economical approach to improve glucose homeostasis.

Funding Sources

USDA Award #2019–67,018-29,260 and the Jim and Lynn Williams Professorship.

Determinants of Postprandial Triglycerides Across the Spectrum of Aging

Objectives

Elevated postprandial triglycerides (TG) are a risk factor for cardiovascular disease, and older adults exhibit greater postprandial lipemia (PPL) compared to younger adults. However, determinants of PPL, especially in older populations, remain poorly defined. This cross-sectional study examined the influence of body composition, lifestyle behaviors, and metabolic risk factors for PPL across the aging spectrum.

Methods

We recruited individuals evenly distributed between the ages of 50–89 years (50% male; 50% female). Participants completed diet and physical activity questionnaires and wore an accelerometer for 5 days. Body composition was measured via bioelectrical impedance. Following an overnight fast, participants also completed an abbreviated fat tolerance test: a blood draw was performed before and 4 hours after consumption of a high-fat meal (9 kcal/kg; 73% fat) to determine fasting and peak postprandial metabolic responses.

Results

56 participants (age groups: 50s, n = 15; 60s, n = 15; 70s, n = 15; 80s,  n = 11) completed the study. Fasting TG did not differ across age groups (50s: 99.7 ± 50.1 mg/dL; 60s: 114.3 ± 71.1 mg/dL; 70s: 102.9 ± 45.0 mg/dL; 80s: 86.9 ± 39.5 mg/dL; P = 0.63). There was also no difference in 4-hour TG across age groups (50s: 162.9 ± 76.9 mg/dL; 60s: 181.9 ± 99.9 mg/dL; 70s: 130.8 ± 82.0 mg/dL; 80s: 130.8 ± 60.6 mg/dL; P = 0.40). Across age groups, variables significantly correlated (p's &lt; 0.05) with 4-hour TG included BMI (r = 0.29), visceral adiposity (r = 0.31), ALT (r = 0.37), fasting glucose (r = 0.27), 4-hour glucose (r = 0.34) and alcohol intake (r = 0.33). In a backward elimination regression (R2 = 0.31), the most predictive variables of 4-hour TG were 4-hour glucose (β = 0.31; P = 0.01), ALT (β = 0.33; P = 0.007), and alcohol intake (β = 0.25; P = 0.04).

Conclusions

In older adults aged 50–89, we identified ALT, postprandial glucose, and alcohol intake as key determinants of postprandial TG. Future studies should aim to explore the relationship between liver health, insulin resistance, alcohol intake, and PPL across the aging spectrum.

Funding Sources

Donna Cadwalader Research and Development Grant, College of Education and Human Sciences and Oklahoma State University Foundation.

Determination of Peak Aerobic Capacity in Normal Weight Obesity and Metabolically Healthy Obesity

Objectives

The true cardiometabolic risk of the novel body composition phenotypes normal-weight obesity (NWO) and metabolically healthy obesity (MHO) remains controversial. Cardiorespiratory fitness, as measured by peak oxygen uptake during exercise (VO2peak), is inversely correlated with CVD and mortality. The objective of this project was to determine VO2peak in NWO and MHO relative to appropriate positive and negative control groups.

Methods

For this cross-sectional study, participants aged 18–50 years were recruited into one of four groups based on BMI, body composition, and metabolic risk factors: NWO (normal BMI with high body fat percentage (BF%)); MHO (obese BMI, high BF%, and up to one of the diagnostic criteria for metabolic syndrome (MetS) as defined by the International Diabetes Federation); MetS (obese BMI, high BF%, and at least three of the diagnostic criteria for MetS); and healthy controls (HC; normal BMI, BF%, and metabolic markers). Participants engaged in a maximal exercise test on a cycle ergometer to determine VO2peak and a DEXA scan to assess BF%. Data were analyzed using one-way ANOVA.

Results

A total of 35 participants completed this study (HC: n = 10; NWO: n = 8; MHO: n = 10; MetS: n = 7). VO2peak was greater in HC (44.2 ± 11.0 ml/kg/min) compared to NWO (28.6 ± 5.1 ml/kg/min; P = 0.002), MHO (25.4 ± 6.7 ml/kg/min; P &lt; 0.0001) and MetS (24.3 ± 8.8 ml/kg/min; P = 0.0002). VO2peak was similar among NWO, MHO, and MetS (p's ≥ 0.76). BF% was lower in HC (23.4 ± 5.5%) compared to NWO (32.6 ± 3.8%; P = 0.0099), MHO (41.9 ± 6.0%; P &lt; 0.0001) and MetS (32.5 ± 6.1%; P = 0.016). BF% was also greater in MHO compared to NWO (P = 0.0085) and MetS (P = 0.0115). There was no significant difference in BF% between NWO and MetS (P &gt; 0.9999). Across groups, there was a strong inverse correlation between BF% and VO2peak (r = −0.83).

Conclusions

VO2peak did not significantly differ among all three at-risk groups (NWO, MHO, and MetS), and all were lower than HC. BF% also did not significantly differ between NWO and MetS groups, and BF% was actually greater in MHO compared to MetS and NWO. NWO and MHO, despite normal BMI and metabolic markers, respectively, have a VO2peak more similar to MetS than HC, suggesting increased cardiometabolic risk.

Funding Sources

American Society for Nutrition Mars. Inc Predoctoral Fellowship.

Daily Triglyceride Kinetics When Consuming a Realistic Western Diet in At-risk Individuals Across the Metabolic Spectrum: A Case Study

Objectives

Most of the day is spent in the postprandial state, in part because of the additive effect of dietary fat from meals on triglycerides (TG), and this response is exacerbated by insulin resistance. However, 24-hr TG kinetics when consuming a realistic, Western diet (WD) remain poorly defined in at-risk individuals. The purpose of this exploratory case study was to compare postprandial 24-hr TG in 3 at-risk individuals defined as having normal-weight obesity (NWO), metabolic syndrome (MetS), and type 2 diabetes (T2D) consuming a WD.

Methods

1 adult male from the following categories were recruited: NWO (i.e., 30% body fat and normal BMI), MetS (also a smoker), and T2D (taking 20 mg Atorvastatin). Upon arrival, a 24-guage indwelling catheter was inserted and a 0.9% NaCl drip initiated. Blood was drawn and TG measured hourly for 18-hrs and every 3-hrs for the last 6-hrs (Alere Cholestech; Hayward, CA). A semi-ad libitum WD (∼46% fat, 36% CHO, 18% protein) was provided consisting of breakfast (Jimmy

Dean's), lunch 4-hrs later (McDonald's), dinner 5-hrs after lunch (Little Caesar's), and a snack 3-hrs after dinner (Blue Bell). Participants slept ≥ 6.5 hrs.

Results

As expected, all participants’ TG remained above fasting ≥ 75% of the 24-hr period and all exhibited peak TG between lunch and dinner. NWO presented with fasting TG of 100 mg/dL, and experienced peak TG of 278 mg/dL and area under the curve (AUC) of 3393 mg/dL. MetS similarly displayed a ∼3-fold increase in TG, although all TG parameters were lower (fasting = 69 mg/dL, peak = 214 mg/dL, AUC = 2772 mg/dL). Lastly, T2D closely resembled NWO with fasting TG of 100 mg/dL, peak TG of 282 mg/dL, and an AUC of 3165 mg/dL.

Conclusions

In this case study, we observed that all 3 at-risk participants’ TG nearly tripled from baseline despite markedly different body composition, risk factors, and health status. NWO and T2D both had an adverse postprandial response per current guidelines (i.e., ≥ 220 mg/dL), but MetS was just below this mark. Surprisingly, NWO had a very similar TG response to T2D and the greatest AUC, although the statin very likely mitigated postprandial TG in T2D. Future, larger studies should seek to confirm our observation that a wide range of at-risk individuals experience a deleterious postprandial TG response during daily living when consuming a WD.

Funding Sources

Internal Sources at Oklahoma State University

Abstract MP17: Circulating Sirt1 And Endothelial Function Are Lower, But Are Not Improved By 8-weeks Of Exercise Training, In Young Adult Females With A History Of Adverse Childhood Experiences

Introduction: Adverse Childhood Experiences (ACEs), in the forms of abuse, neglect, and violence, are associated with augmented blood pressures in young adulthood and CVD risk later in life. These effects are independent of negative health behaviors, suggesting that ACEs are biologically embedded. Sirtuin 1 (SIRT1) is a highly conserved nicotinamide-adenine dinucleotide-dependent deacetylase that plays an important role in the regulation of vascular function in aerobic organisms, while endothelial dysfunction is an antecedent of overt CVD. Hypotheses: We hypothesized that 1) circulating SIRT1 concentrations and endothelial function (EF) would be lower in young adult females with a history of ACEs when compared to age-matched controls with no history of ACEs, and 2) that 8-weeks of exercise training would improve circulating SIRT1 and EF in those with ACEs (ACE EXT ) compared to non-exercise controls with (ACE CON ) or without (NEG CON ) a history of ACEs.

Methods: Forty-two young adult females (mean ± SE, age = 21 ± 0.4 y) were randomly assigned to either the ACE EXT (n = 14) or ACE CON group (n = 14) if their ACE score was ≥ 4, or assigned to the NEG CON group (n = 14) if their ACE score was 0. Prior to and after an 8-week intervention, serum was obtained from fasting venous blood draws for SIRT1 quantification via ELISA, and EF was assessed by quantifying flow-mediated dilation (FMD) using duplex ultrasound of the brachial artery. During the intervention, females in the ACE EXT group completed 2 sessions each of resistance and aerobic interval training every week, whereas the ACE CON and NEG CON groups maintained habitual activity levels. Effects of ACEs were examined by collapsing the ACE groups and comparing them to the NEG CON group with unpaired comparisons (ACE vs. NEG CON ), whereas the group*intervention interaction was assessed using a one-way ANOVA on the absolute change scores (ACE EXT vs. ACE CON vs. NEG CON ).

Results: SIRT1 (649.6 ± 27.0 vs. 809.5 ± 51.0 pg/ml; t 38 = 3.05, p = 0.004) and EF were lower (6.0 ± 0.7 vs. 9.4 ± 0.9%; U = 77.5, p = 0.002) in the females exposed to ACEs compared to the controls. Further, EF was moderately related ( rho = 0.58, p < 0.001) to SIRT1 concentrations at baseline across the sample. However, 8-weeks of exercise training resulted in no significant improvements in either circulating SIRT1 ( p = 0.94) or FMD ( p = 0.16).

Conclusions: This is the first study, to our knowledge, to examine the influence of ACEs on SIRT1 levels and endothelial function. Our data provide initial evidence that young adult females with a history of ACEs exhibit decreased vascular function early in adulthood, which may help explain the increased risk of CVD associated with ACEs. Importantly, our data also suggest that SIRT1 may be an important link between ACEs and vascular dysfunction. However, the 8-week exercise intervention was not effective for improving either outcome in those with a history of ACEs in this study.

Fasting and Postprandial Triglycerides Across Older Adulthood: A Cross-sectional Study

Objectives

Elevated postprandial triglycerides (TG) are a risk factor for cardiovascular disease (CVD). Although some evidence suggests that older adults exhibit greater postprandial TG than younger adults, it is unknown how postprandial lipid tolerance changes across the spectrum of older adulthood. This cross-sectional study examines postprandial TG responses across the spectrum of aging, as well as factors that may modify this response.

Methods

We are recruiting individuals into four age categories (age 50–59, 60–69, 70–79, 80–89 years), with an equal number of participants and sex distribution in each group. Participants undergo body composition testing via bioelectrical impedance analysis and complete a 130-item food frequency questionnaire. Participants return to the lab after a 10-hour fast and blood is drawn both before and 4 hours after consumption of a high-fat meal (9 kcal/kg body mass; 73% fat, 26% CHO) to determine fasting and postprandial TG.

Results

Thirty participants (50’s: n = 12; 60’s: n = 11; 70’s: n = 4; 80’s: n = 3) have completed the study (total N = 60). There was no difference (P = 0.52) in BMI across age groups (50’s: 29.5 ± 5.4 kg/m2; 60’s: 29.1 ± 5.5 kg/m2; 70’s: 25.9 ± 3.8 kg/m2; 80’s: 26.1 ± 1.6 kg/m2). There was also no difference (P = 0.68) in body fat (BF%) across age groups (50’s: 37.5 ± 7.2%; 60’s: 39.53 ± 7.0%; 70’s: 43.6 ± 8.2%; 80’s: 39.5 ± 18.1%). Similarly, there was no difference (P = 0.76) in fasting TG across age groups (50’s: 98.8 ± 40.6 mg/dL; 60’s: 117.9 ± 83.3 mg/dL; 70’s: 105.3 ± 39.7 mg/dL; 80’s: 79.7 ± 31.7 mg/dL), nor was there a difference (P = 0.74) in 4-hr TG (50’s: 162.3 ± 70.8 mg/dL; 60’s: 187.5 ± 105.5 mg/dL; 70’s: 181.8 ± 89.6 mg/dL; 80’s: 130.7 ± 55.1 mg/dL). Lastly, there was no difference (P = 0.16) in fruit and vegetable (FV) intake (50’s: 4.4 ± 1.9 servings/day (s/d); 60’s: 8.2 ± 5.5 s/d; 70’s: 6.2 ± 4.6 s/d; 80’s: 7.9 ± 2.4 s/d).

Conclusions

At this point in the study, it cannot be concluded that there is a significant difference in fasting or postprandial TG across aging strata, possibly due to no differences in BMI, BF%, or FV intake. When complete, this study will provide valuable insight with regard to the impact of aging and other lifestyle factors on postprandial lipemia and subsequent CVD risk.

Funding Sources

This project is funded by the Donna Cadwalader Research and Development Grant.

Association of Body Composition, Glucose Control, and Diet with Postprandial Triglycerides and Vascular Function

Objectives

Excessive postprandial lipemia (PPL) following intake of a high-fat meal (HFM) is a risk factor for cardiovascular disease (CVD). We recently observed significantly lesser PPL in more active individuals, irrespective of age. This project examined the association of body composition, glucose control, and dietary intake with postprandial triglycerides (TG) and vascular function in groups that differed by age and physical activity level.

Methods

We recruited 4 groups of adults: younger active (YA; age 22.1 ± 1.4 y; n = 9), younger inactive (YI; age 22.6 ± 3.7 y; n = 8), older active (OA; age 68.4 ± 7.7 y; n = 8), and older inactive (OI; age 67.7 ± 7.2 y; n = 7). Participants completed a 3-day food record including 2 weekdays and 1 weekend day. Following a 10-hour overnight fast and 2 days of exercise avoidance, participants consumed a HFM (12 kcal/kg; 63% fat, 34% carbohydrate). Serial blood draws were then collected every hour for 6 hours to measure metabolic responses. Vascular function was assessed using flow-mediated dilation (FMD) at baseline (BL), 2-hours, and 4-hours post-meal. Fasting insulin and glycated hemoglobin (HbA1c) were measured pre-meal. Body composition was assessed using bioelectrical impedance analysis (Seca mBCA 514).

Results

After controlling for physical activity and age via partial correlation, visceral adiposity was associated with TG total area under the curve (P = 0.04; r = 0.38), while body fat % was inversely associated with BL FMD (P = 0.0007; r = −0.50). HOMA-IR was not associated with visceral adiposity or body fat % (P’s ≥ 0.08). Postprandial metabolic and vascular responses were not associated with skeletal muscle mass (P’s ≥ 0.07), fasting insulin (P’s ≥ 0.30), HOMA-IR (P’s ≥ 0.40) or HbA1c (P’s ≥ 0.29). After adjusting for total caloric intake, BL FMD was positively associated with dietary fiber (P = 0.006; r = 0.50) and negatively associated with dietary sugar (P = 0.01; r = −0.46).

Conclusions

This study identified body fat distribution, sugar, and fiber as correlated factors for postprandial metabolic and vascular responses when also considering age and physical activity. This warrants future studies to examine further the role of these factors in determining PPL and vascular function.

Funding Sources

This study was funded by the College of Human Sciences at Oklahoma State University.

Effect of Black Coffee on Fasting Metabolic Markers and an Abbreviated Fat Tolerance Test

Objectives

Common clinical recommendations direct patients to report fasted when blood work (e.g., triglycerides [TG], glucose [Glu]) will take place, which typically excludes black coffee consumption. Despite its negligible calorie content, caffeinated coffee increases fatty acid mobilization. However, whether this effect meaningfully alters fasting metabolic testing or influences the results of a fat tolerance test is unclear. We investigated whether allowing black coffee intake within a fast prior to blood work affected fasting TG and Glu, as well as the postprandial lipemic and glycemic response following an abbreviated fat tolerance test.

Methods

In a randomized crossover design, participants were instructed to consume only water, or were allowed 8 fluid ounces of black coffee at the end of a 10-hr fast. Next, TG and Glu were assessed using the Cholestech LDX system (Alere Cholestech: Hayward, CA, USA) before and after a previously validated 4-hr fat tolerance test (9 kcal/kg; 73% fat, 26% CHO). Paired t-tests were performed to assess baseline and 4-hr values, absolute change, and % change for both TG and Glu.

Results

Preliminary analysis of healthy subjects (n = 3 of 10 subjects completed; 1 M/2F; age 20.3 ± 2.3; BMI 25.7 ± 0.6) revealed that consuming coffee prior to the blood draw did not affect fasting TG (Mean difference (MD) = 7.0 mg/dL; P = 0.68). Similarly, the lipemic response was not altered by coffee, evidenced by no alterations in 4-hr TG (MD = 7.6 mg/dL), Δ TG (MD = 14.7 mg/dL), and % change in TG (MD = 29.1%; all P’s ≥ 0.52). Fasting Glu was unchanged following coffee consumption (MD = 29.1 mg/dL; P = 0.90), and indicators of the glycemic response such as 4-hr Glu (MD = 0.0 mg/dL), Δ Glu (MD = 1.0 mg/dL), and % change (MD = 1.2%), were similar among water and coffee trials (all P's ≥ 0.73).

Conclusions

At this point in the study, coffee consumption does not seem to alter fasting TG or markers of fat tolerance. Additionally, fasting Glu and the glycemic response do not appear to be influenced by coffee consumption. When completed, this study will help answer the practical question of whether coffee need be avoided prior to basic metabolic testing or a fat tolerance test, which may provide increased consistency in metabolic assessment and potentially improve patients’ clinical experience.

Funding Sources

Lew Wentz Research Scholars Program at Oklahoma State University.

The Effects of Wheat Germ Supplementation on Anthropometric, Biochemical, and Stool Measures in Overweight Adults

Objectives

This study investigated the effects of a 4-week wheat germ supplementation on anthropometric, biochemical, and stool measures in overweight adults.

Methods

Forty overweight (body mass index = 25.0–30 kg/m2) adults (18–45 years old) were recruited to participate in this randomized controlled study. After initial screening, participants were asked to consume energy balls containing either cornmeal (control) or 30 g of wheat germ (WG) daily for 4 weeks. The energy balls were isocaloric and provided an additional 225 kcal/day. Participants were asked to otherwise maintain their normal diet and physical activity. Anthropometric and metabolic parameters, as well as dietary (3-day food record), medical history, physical activity (Yale Physical Activity Survey) and stool measures (Bristol Stool Chart and the Cleveland Clinic Constipation Scoring System) were assessed at baseline and at the end of the 4-week supplementation period.

Results

Thirty-nine participants completed the 4-week supplementation (n = 20 and 19 for the WG and control group, respectively). There were no significant differences in anthropometrics, metabolic parameters (i.e., lipid panel, glucose, and HbA1c) or stool measures between the control and WG groups at baseline or at the end of supplementation. However, when comparing change from baseline, significant differences in % body fat, HbA1c, and constipation score were observed between the two groups. Individuals who received the WG supplement exhibited a greater increase in % body fat (0.68 ± 0.28% vs. 0.40 ± 0.36%, P = 0.02) and a greater decrease in HbA1c (−0.095 ± 0.05% vs. −0.039 ± 0.04%, P = 0.04). On the other hand, the control group (−1.00 ± 0.57) perceived a more significant improvement (P = 0.01) in their constipation score compared to WG (−0.85 ± 0.42).

Conclusions

Similar to our findings in animals, this study demonstrates that daily supplementation with 30 g of WG may be beneficial in glucose homeostasis as indicated by improvement in HbA1C, despite increasing % body fat. Whether the effects of WG on HbA1C will be observed at longer supplementation duration or in other populations such as obese individuals or pre-diabetics needs to be investigated in future studies.

Funding Sources

United States Department of Agriculture.

Postprandial Lipemic Responses to Various Sources of Dietary Fat in Healthy Adults (P08-101-19)

Objectives

Postprandial lipemia (PPL), or a large increase in triglycerides (TG) post-meal, has been identified as an independent risk factor for cardiovascular disease (CVD) and may be a stronger predictor of CVD risk than fasting TG. However, the effects of various sources of dietary fat on PPL are not well understood. Therefore, the objective of this project is to examine the postprandial TG response to commonly consumed sources of dietary fat.

Methods

Participants engaged in 4 randomized meal trials separated by at least 1 week. For each meal trial, following a 10-hour overnight fast, an intravenous catheter was inserted into a forearm vein from which a fasting blood draw was taken. Thereafter, participants consumed a standard high-fat meal (HFM; 13 kcal/kg; 61% fat, 32% CHO) with the fat source derived from either butter (B), virgin unrefined coconut oil (CoO), extra virgin olive oil (OO), or canola oil (CaO). Serial blood draws were collected hourly for 6-hours post-meal to quantify postprandial TG responses.

Results

Seven healthy participants have completed the protocol (4 M/3F; age 23.8 ± 1.3 years; BMI: 25.5 ± 7.2 kg/m2). Fasting TG was not different (P = 0.26) across trials (B: 76.1 ± 41.6 mg/dL; CoO: 69.6 ± 27.1 mg/dL; OO: 75.3 ± 45.7 mg/dL; CaO: 85.1 ± 34.7 mg/dL). Two-way ANOVA revealed a significant time effect (P < 0.0001) but no time x meal interaction (P = 0.51) or overall meal effect (P = 0.10). Meal trials did not differ (P = 0.14) with regard to TG total area under the curve (AUC; B: 772.5 ± 449.5 mg/dL × 6 hr; CoO: 605.6 ± 268.2 mg/dL × 6 hr; OO: 726.3 ± 485.3 mg/dL × 6 hr; CaO: 715.1 ± 355.4 mg/dL × 6 hr). However, TG incremental AUC was significantly different (P = 0.03) across meal trials (B: 315.6 ± 229.1 mg/dL × 6 hr; CoO: 188.1 ± 151.7 mg/dL × 6 hr; OO: 274.7 ± 246.3 mg/dL × 6 hr; CaO: 204.2 ± 206.7 mg/dL × 6 hr), although no post hoc pairwise comparisons were significantly different (B vs CoO: P = 0.06; B vs OO: P = 0.76; B vs CaO: P = 0.06; CoO vs OO: P = 0.45; CoO vs CaO: P = 0.98; OO vs CaO: P = 0.19).

Conclusions

In this continuing experiment, postprandial TG responses to HFMs comprised of different dietary fat sources are largely similar to this point, although a difference in incremental AUC was observed. Upon completion, this study will advance our understanding of the effects of commonly consumed dietary fats on PPL, an indicator of CVD risk.

Funding Sources

Institutional internal funding.

Glycemic Control Outcomes Following Three Weeks of Added Sugar-Sweetened Beverages or 100% Fruit Juice: A Randomized Controlled Trial (P12-015-19)

Objectives

Regular consumption of sugar-sweetened beverages (SSBs) is associated with increased risk for type 2 diabetes mellitus and other obesity-related diseases. Evidence regarding the effect of 100% fruit juice on glycemic control is conflicting, with little research assessing the metabolic effects of SSBs versus 100% fruit juice, particularly in young, healthy individuals. Therefore, the aim of the current study was to determine whether there were differences in glycemic control outcomes following three weeks of added caffeine-free soda, 100% fruit juice, or water in healthy, young adults.

Methods

In a 3-arm randomized controlled trial, 36 participants (21.2 ± 2.8 yrs) consumed one of three beverages for three weeks: water (W), caffeine-free soda (S), or 100% fruit juice (FJ). At baseline and following the 3-week intervention, participants completed anthropometric (height, weight, waist circumference, body composition via dual energy x-ray absorptiometry) and glycemic control assessments (fasting glucose (mg/dL), fasting insulin (IU/mL), and a 2-hour glucose tolerance test (OGTT)). Following baseline assessments, participants consumed two servings/day (∼710 mL) of their randomized beverage for three weeks, along with their habitual diets. Insulin resistance was calculated using homeostatic model assessment (HOMA-IR). Differences between beverages for glycemic control outcomes were determined using ANOVA.

Results

Following the 3-week intervention, changes in fasting glucose were not significantly different between beverage conditions (W:4.70 ± 7.57%, S:5.46 ± 9.79%, FJ:4.93 ± 5.32%; P = 0.97), nor were changes in fasting insulin (W:25.77 ± 33.65%, S:15.71% ± 69.84%, FJ:25.86 ± 54.92%; P = 0.88). Changes in HOMA-IR were not different between beverage conditions (P = 0.96) and similarly, 2-hour OGTT revealed no differences between beverage conditions for glucose (P = 0.82) or insulin incremental area under the curve (P = 0.44).

Conclusions

In healthy, young adults, under free-living conditions, there were no differences in glycemic control outcomes when adding two servings of SSBs as compared to 100% fruit juice for three weeks. Longer-term trials are needed to elucidate the potential differential glycemic control responses to SSBs versus 100% fruit juice.

Funding Sources

N/A.

Impact of Age and Physical Activity on Postprandial Metabolic Responses (OR22-07-19)

Objectives

Large metabolic responses to high-fat meals (HFM) are known to create a deleterious physiological state. However, there is limited research describing the differential influences of age and physical activity level on meal metabolism, specifically in healthy older individuals. The goal of this project is to quantify the impact of age and physical activity on metabolic outcomes immediately following meal consumption in healthy men and women.

Methods

We recruited 4 groups of individuals: younger active (YA; age 22.3 ± 1.5 y; n = 7), younger inactive (YI; age 22.6 ± 4.0 y; n = 7), older active (OA; age 70.5 ± 7.8 y; n = 6), and older inactive (OI; age 69.6 ± 7.6 y; n = 5). Following a 10-hour overnight fast, an intravenous catheter was inserted into a forearm vein from which a fasting blood draw was taken. Participants then consumed a HFM (12 kcal/kg; 63% fat, 34% carbohydrate). Serial blood draws were conducted hourly for 6 hours to measure postprandial triglyceride (TG) and glucose (GLU) responses. Prior to the HFM, participants refrained from exercise for 48 hours to remove the confounding effects of recent acute exercise. One-way or two-way ANOVA was used, as appropriate, to compare groups with regard to postprandial metabolic outcomes.

Results

Groups were similar with regard to fasting GLU (P = 0.77) and TG (P = 0.06). There was a time effect for both GLU and TG in the postprandial period (P < 0.0001). A group effect was present for TG (P = 0.048), but not GLU (P = 0.07). There were no significant group differences in TG in post hoc comparisons (YA vs. YI, P = 0.41; YA vs. OA, P > 0.99; YA vs. OI, P = 0.08; YI vs. OA, P = 0.42; YI vs. OI, P = 0.67; OA vs. OI, P = 0.08). Total area under the curve (AUC) for TG was significantly different across groups (P = 0.0498; YA = 618.8 ± 103.1 mg/dL x 6 hr, YI = 836.4 ± 402.6, OA = 609.0 ± 234.6, OI = 993.4 ± 80.9), but incremental AUC was not different (P = 0.18). Groups did not differ with regard to GLU total (P = 0.07) or incremental AUC (P = 0.26). Peak TG (P = 0.38) and GLU (P = 0.18) responses did not differ across groups.

Conclusions

In this ongoing experiment, we are observing group differences in postprandial TG based on age and physical activity level. When complete, this study will highlight the independent effects of aging and physical activity on postprandial metabolic responses, which are integral components in CVD risk.

Funding Sources

Oklahoma State University.

The Reproducibility of an Abbreviated Fat Tolerance Test in Young Healthy Participants: A Pilot Study (P12-029-19)

Objectives

Triglyceride (TG) responses following a high-fat meal are more strongly associated with cardiovascular disease (CVD) risk compared with fasting TG levels. The current protocol for assessing post-meal TG is a burdensome process, involving serial blood draws for up to 8 hours. We have developed an abbreviated fat tolerance test (AFTT) that yields highly similar TG results relative to the standard protocol. The objective of this study is to determine whether the AFTT is reproducible and how it compares to the reproducibility of the oral glucose tolerance test (OGTT), a metabolic challenge already in clinical use.

Methods

In a randomized crossover design, 6 healthy participants (2 M/4F, age: 25.8 ± 9.4 years, BMI: 22.6 ± 2.6 kg/m², fasting TG: 69.8 ± 9.8 mg/dL, fasting glucose: 93.5 ± 5.1 mg/dL, A1C: 5.3% ± 0.34%) completed 2 AFTT's separated by 1 week followed by 2 OGTT's separated by 1 week, or vice versa. There was a 2-week washout period between the AFTT's and OGTT's. For each AFTT and OGTT, a baseline blood draw was taken followed by either consumption of a high-fat shake (73% fat, 26% CHO; 9 kcal/kg) (AFTT) or a standard 75 g glucose drink (OGTT). Following consumption of the AFTT, participants left the lab and returned 4 hours later for a post-meal blood draw. Following consumption of the OGTT, participants remained in the lab for 2 hours and a post-meal blood draw was taken.

Results

The mean difference in 4-hour postprandial TG change from baseline between the 2 AFTTs was 5.2 mg/dL, while the mean difference in 2-hour glucose change between the 2 OGTTs was 17.5 mg/dL. The 4-hour TG change results from the 2 AFTT's were highly correlated (r = 0.96, P = 0.003), while the 2-hour change results from the 2 OGTTs were not (r = 0.17, P = 0.75). The within-subjects coefficient of variation (WCV) for 4-hour TG concentrations between the 2 AFTT's was 16%, suggesting moderate reproducibility, while the WCV for 2-hour glucose concentrations between the 2 OGTT's was 24%, indicating low reproducibility.

Conclusions

These preliminary data suggest that the AFTT response is reproducible, potentially more than the OGTT. While further assessment in a larger sample is necessary, the AFTT could advance postprandial TG testing toward greater clinical feasibility.

Funding Sources

Funding provided by internal sources at Oklahoma State University.

EDDIX--a database of ionisation double differential cross sections

The use of Monte Carlo track structure is a choice method in biophysical modelling and calculations. To precisely model 3D and 4D tracks, the cross section for the ionisation by an incoming ion, double differential in the outgoing electron energy and angle, is required. However, the double differential cross section cannot be theoretically modelled over the full range of parameters. To address this issue, a database of all available experimental data has been constructed. Currently, the database of Experimental Double Differential Ionisation Cross sections (EDDIX) contains over 1200 digitalised experimentally measured datasets from the 1960s to present date, covering all available ion species (hydrogen to uranium) and all available target species. Double differential cross sections are also presented with the aid of an eight parameter functions fitted to the cross sections. The parameters include projectile species and charge, target nuclear charge and atomic mass, projectile atomic mass and energy, electron energy and deflection angle. It is planned to freely distribute EDDIX and make it available to the radiation research community for use in the analytical and numerical modelling of track structure.

On coenrollment in clinical resuscitation studies: review and experience from randomized trials

CONTEXT

Patients with acute life-threatening illness are candidates for enrollment in multiple trials. Whether patients are enrolled in multiple trials has implications for patient safety, trial enrollment duration, and study validity.

OBJECTIVE

We review issues related to coenrollment and propose guidelines for when it should be allowed.

RESULTS

There is no regulatory prohibition on coenrollment of patients in more than one study. Randomized trials of interventions for a variety of clinical conditions have allowed coenrollment without any reported deleterious impact on either study. Guidelines for coenrollment are proposed.

Hepatocyte growth factor is secreted by osteoblasts and cooperatively permits the survival of haematopoietic progenitors

Human osteoblasts (HOBs) support the growth of human haematopoietic progenitor cells, and support the survival and limited expansion of long-term culture-initiating cells. Using human CD34+ cells and the murine myelomonocytic cell line NFS-60 as targets, we previously found that one component of HOB-derived haematopoietic activity is cell-associated granulocyte colony-stimulating factor (G-CSF). However, antibody failed to neutralize all the activity, suggesting that more than one factor supports haematopoietic cells. In the present investigations, we asked whether the HOB-derived, non-G-CSF secreted activity was as a result of other known growth factors. We found that, among the cytokines expressed by HOBs, only hepatocyte growth factor (HGF) and G-CSF stimulated NFS-60 cell proliferation. HOB cells and osteosarcoma cells secreted biologically active HGF, although the levels varied considerably. Moreover, addition of neutralizing HGF antibody to CD34+ cell/HOB co-cultures resulted in a significant reduction ( approximately 50%) in the ability of the HOBs to support haematopoietic progenitor cells. These results suggest that a major component of osteoblast-derived haematopoietic activity is HGF. Secretion of HGF, in concert with cell-associated cytokines such as G-CSF, may account for the stem cell-stimulating activities of osteogenic cells and, thereby, the unique stem cell-supporting role of the osteoblasts within the bone marrow microenvironment.

Anthropometric measures and risk of death in children with end-stage renal disease

We evaluated the association between anthropometric measurements and death among pediatric patients with end-stage renal disease (ESRD) using data from the Pediatric Growth and Development Special Study (PGDSS) from the US Renal Data System. Height, growth velocity, and body mass index (BMI) were used for the analysis of 1,949 patients in the PGDSS. To standardize these measurements, SD scores (SDSs) were calculated using population data from the Third National Health and Nutrition Examination Survey. Using Cox proportional hazards models, we assessed the association between anthropometric measures and death, controlling for demographic factors and stratifying by age. Multivariate analysis showed that each decrease by 1 SDS in height was associated with a 14% increase in risk for death (adjusted relative risk [aRR], 1.14; 95% confidence interval [CI], 1.02 to 1.27; P = 0.017). For each 1 SDS decrease in growth velocity among patients in our sample, the risk for death increased by 12% (aRR, 1.12; 95% CI, 1.00 to 1.25; P = 0.043). There was a statistically significant U-shaped association between BMI and death (P = 0.001), with relatively low and high BMIs associated with an increased risk for death. In children with ESRD, growth delay and extremes in BMI are associated with an increased risk for mortality.

Screening plasma aluminum levels in relation to aluminum bone disease among asymptomatic dialysis patients

Aluminum accumulation in plasma and tissues is a well-described complication among persons undergoing peritoneal dialysis or hemodialysis. Excess bone aluminum is associated with low bone formation rates and increased risk for fractures. Current recommendations for care of patients with end-stage renal disease include screening for aluminum toxicity with plasma aluminum levels; patients with levels below 40 microg/L are considered to be at low risk for aluminum bone disease (ABD). We examined data from the Toronto Renal Osteodystrophy Study to evaluate the performance of plasma aluminum levels in screening for ABD. Two hundred fifty-eight unselected patients undergoing peritoneal dialysis (n = 143) or hemodialysis (n = 115) underwent diagnostic bone biopsy and measurement of plasma aluminum level. Sixty-nine patients (26.7%) were identified as having ABD, defined as low or normal bone formation rates with 25% or more bone surface aluminum staining. Plasma aluminum level was strongly associated with the presence of ABD; the odds ratio was 1.4 for each increase of 10 microg/L (95%CI, 1.2, 1.6). However, only 50.1% of patients with a plasma aluminum level of 40 microg/L or greater had ABD, whereas 14.2% of patients with a level below this threshold also had ABD. Using this cutoff level of 40 microg/L, the sensitivity and specificity were 65.2% and 76.7%, respectively. We conclude that although there is a correlation between high aluminum levels and ABD, a patient's plasma aluminum level does not predict well the presence of ABD in spite of a relatively high prevalence of disease.

Is greater continuity of care associated with less emergency department utilization?

BACKGROUND

The benefits of continuity of care (COC) have not been firmly established for pediatric patients.

OBJECTIVE

To assess whether greater COC is associated with lower emergency department (ED) utilization.

SETTING

Outpatient teaching clinic at Children's Hospital and Regional Medical Center, Seattle, WA.

PATIENTS

All 785 Medicaid managed care children ages 0 to 19 years followed at Children's Hospital and Regional Medical Center between 1993 to 1997 who had at least four outpatient visits.

METHODS

Retrospective claims-based analysis. COC was quantified based on the number of different care providers in relation to the number of clinic visits.

RESULTS

Attending COC was significantly greater than resident COC. In a multiple event survival analysis, compared with those patients in the lowest tertile of attending COC, those in the middle tertile had 30% lower ED utilization (hazard ratio 0.70 [0.53-0.93]) and those in the highest tertile had 35% lower ED use (hazard ratio 0.65 [0.50-0.80]). Resident COC was not significantly associated with ED use.

CONCLUSION

Greater COC with attending physicians in outpatient teaching clinics is associated with lower ED utilization.

Dose-response relationship of intrathecal morphine for postcesarean analgesia

BACKGROUND

This series investigated the quality of analgesia and the incidence and severity of side effects of intrathecal morphine for post-cesarean analgesia administered over a dose range of 0.0-0.5 mg.

METHODS

ONE hundred eight term parturients undergoing cesarean delivery at term and given spinal anesthesia were randomized to receive a single dose of intrathecal morphine (0.0, 0.025, 0.05, 0.075, 0.1, 0.2, 0.3, 0.4, or 0.5 mg). A patient-controlled analgesia (PCA) device provided free access to additional analgesics. PCA morphine use, incidence and severity of side effects, and need for treatment interventions were recorded for 24 h. Data were analyzed with analysis of variance and linear regression analysis for trends among groups.

RESULTS

Patient-controlled analgesia use differed significantly between groups; PCA use was higher in the control group than in groups receiving 0.075, 0.1, 0.3, 0.4, or 0.5 mg. Twenty-four-hour PCA morphine use was 45.7 mg lower (95% CI, 4.8-86.6 mg lower) in the 0.075-mg group than the control group. There was no difference in PCA morphine use between the 0.075- and 0.5-mg groups (95% CI, 36.8 mg lower to 45.0 mg higher); despite a fivefold increase in intrathecal morphine dose, PCA morphine use remained constant. There was no difference between control and treatment groups or among treatment groups with respect to nausea and vomiting. Pruritus and the need for treatment interventions increased in direct proportion to the dose of intrathecal morphine (linear regression, P = 0.001 and P = 0.0002, respectively).

CONCLUSIONS

These data indicate there is little justification for use of more than 0.1 mg for post-cesarean analgesia. For optimal analgesia, augmentation [corrected] of intrathecal morphine with systemic opioids may be necessary.

Risk of death among chronic dialysis patients infected with hepatitis C virus

Hepatitis C virus (HCV) infection is highly prevalent among chronic dialysis patients (10% to 40%) and is the most common cause of chronic liver disease. However, there are no studies estimating the risk for death among dialysis patients infected with HCV compared with those not infected. We conducted a prospective cohort study to estimate the risk for death among chronic dialysis patients infected with HCV compared with those not infected. In 1992, 200 patients (91%) who had been undergoing dialysis therapy for at least 6 months consented to be screened for HCV infection by enzyme immunoblot assay and polymerase chain reaction (PCR). Information about potential confounders and potential risk factors for death and HCV infection was obtained from the dialysis center database. Patient outcomes collected included death, transplantation, and loss to follow-up. The Cox proportional hazards model was used to estimate the odds of death among dialysis patients who were positive for the HCV antibody and HCV RNA compared with negative patients. Forty-four patients (22%) were HCV antibody positive. Thirty-four patients (17%) were HCV RNA positive. Patients in the HCV RNA-positive group were more likely to be younger (51.8+/-12.6 v 57.2+/-17.3 years of age), men (77% v 54%), and black (65% v 37%). None of the home hemodialysis or peritoneal dialysis patients were HCV RNA positive, whereas one of the home hemodialysis and one of the peritoneal dialysis patients were HCV antibody positive. Two patients became infected with HCV during the follow-up period. Patients who were HCV RNA positive and those who were HCV antibody positive were at increased risk for death compared with patients who were negative (adjusted relative risk [aRR]=1.78; 95% confidence interval [CI], 1.01 to 3.14; P=0.045; and aRR=1.97; 95% CI, 1.16 to 3.33; P=0.012, respectively), after adjusting for time on dialysis, race, transplantation, and age. We conclude that HCV infection increased the risk for death during the study period compared with those not infected. Further studies should assess the measures used to prevent and treat HCV infection.

Effect of alpha-difluoromethylornithine on rectal mucosal levels of polyamines in a randomized, double-blinded trial for colon cancer prevention

BACKGROUND

Polyamines (e.g., putrescine, spermidine, and spermine) are required for optimal cell growth. Inhibition of polyamine synthesis suppresses carcinogen-induced epithelial cancers, including colon cancer, in animal models. In a short-term phase IIa trial, we determined that low doses of alpha-difluoromethylornithine (DFMO), an inhibitor of ornithine decarboxylase (an enzyme involved in polyamine synthesis), reduced the polyamine content of normal-appearing rectal mucosa of subjects with a prior history of resected colon polyps. In a follow-up study, we have attempted to determine the lowest dose of DFMO that can suppress the polyamine content of rectal mucosa over a course of 1 year with no or minimal side effects.

METHODS

Participants were randomly assigned to daily oral treatment with a placebo or one of three doses (0.075, 0.20, or 0.40 g/m2) of DFMO. Baseline and serial determinations of polyamine levels in rectal mucosa and extensive symptom monitoring (including audiometric measurements, since DFMO causes some reversible hearing loss at higher doses) were performed over a 15-month period.

RESULTS

DFMO treatment reduced putrescine levels in a dose-dependent manner. Following 6 months of treatment, doses of 0.20 and 0.40 g/m2 per day reduced putrescine levels to approximately 34% and 10%, respectively, of those observed in the placebo group. Smaller decreases were seen in spermidine levels and spermidine:spermine ratios. Polyamine levels increased toward baseline values after discontinuation of DFMO. Although there were no statistically significant differences among the dose groups with respect to clinically important shifts in audiometric thresholds and nonaudiologic side effects, statistically significant higher dropout and discontinuation rates were observed in the highest dose group.

CONCLUSIONS

Polyamine levels in rectal mucosa can be continuously suppressed by daily oral doses of DFMO that produce few or no side effects. A dose of 0.20 g/m2 can be used safely in combination phase IIb or single-agent phase III chemoprevention trials.

Association of hepatitis C virus infection with mortality and graft survival in kidney-pancreas transplant recipients

BACKGROUND

Although most studies have not demonstrated decreased patient or graft survival in kidney-alone allograft recipients infected with hepatitis C virus (HCV), the impact of HCV infection on patient and graft survival in HCV-infected kidney-pancreas recipients has not been studied.

METHODS

We undertook a retrospective cohort analysis of 137 kidney-pancreas transplant recipients who were transplanted between January 1989 and May 1996. HCV infection was determined by a positive polymerase chain reaction. Relative risk of death and graft failure was calculated using the Cox proportional hazards model with time-dependent covariates. Relative risks were adjusted (aRR) to control for the number of OKT3-treated rejections and cytomegalovirus status of the recipient at the time of transplantation.

RESULTS

Mean length of follow-up was 30.4 months in the HCV-infected patients compared with 31.7 months in noninfected patients. Seven (5.1%) patients were infected with HCV before transplant, one (1%) relapsed after transplantation, and four (2.9%) acquired the infection after transplantation. The HCV-infected group had a 3.7-fold (95% confidence interval [CI], 1.0-13.5) increased risk of death after transplant compared with the HCV-negative group, with an aRR of 5.5 (95% CI, 1.5-20.0). Death in the HCV-infected group (n=3) was generally the result of liver failure and sepsis, whereas death for those in the uninfected group (n=11) was primarily of cardiovascular origin. Patients infected with HCV were 3.4-fold (95% CI, 1.1-10.1) more likely to develop kidney graft failure than HCV-negative patients with an aRR of 5.1 (95% CI, 1.7-15.4). The risk of pancreatic allograft failure was not significantly increased.

CONCLUSIONS

We conclude that HCV infection in kidney-pancreas transplant patients results in a significantly increased risk of kidney allograft failure and death.