The Drug Burden Index is associated with Measures of Cognitive Function Among Older Adults in the Health, Aging, and Body Composition Study

BACKGROUND

Anticholinergic and sedative medications impact cognition among older adults. The Drug Burden Index (DBI) is a validated measure of exposure to these medications, with higher DBI scores indicating higher drug burden. This ancillary analysis investigated the association between DBI and cognition assessed by the Modified Mini-Mental State Examination (3MS) and the Digit Symbol Substitution Test (DSST).

METHODS

The Health, Aging, and Body Composition Study was a prospective study of community-dwelling adults ages 70-79 years at enrollment. Using data from years 1, 5, and 10, DBI was calculated using medication data per participant. Linear mixed modeling was used to assess cross-sectional and longitudinal effects of DBI on 3MS and DSST. Adjusted models included biological sex, race, education level, APOE status, and death. Sensitivity analyses included testing the strength of the associations for each year and testing attrition due to death as a possible confounding factor via Cox-Proportional Hazard models.

RESULTS

After adjustment, DBI was inversely associated with 3MS and DSST scores. These associations became stronger in each subsequent year. Neither DBI at year 1 nor within-person change in DBI were predictive of longitudinal declines in either cognitive measure. Sensitivity analyses indicated that DBI, 3MS, and DSST were associated with a greater risk of attrition due to death.

CONCLUSIONS

Results suggest that in years when older adults had a higher DBI scores, they had significantly lower global cognition and slower processing speed. These findings further substantiate the DBI as a useful pharmacological tool for assessing the effect of medication exposure.

Neuroprotective Potential of Brown Seaweed Phytochemicals in Rodent Models of Cerebral Ischemia

Cerebral ischemia, a condition with insufficient blood flow in the brain, is associated with cognitive and behavioral changes. The underlying cellular mechanisms of ischemia-induced brain damage include oxidative stress and inflammation. Cerebral ischemia is a major cause of death and long-term disability; thus, investigating novel dietary sources and their therapeutic potentials have gained interest. Seaweed contains various functional phytochemicals with antioxidant and anti-inflammatory effects. Studies have reported that consumption of seaweed is negatively associated with the risk of cardiovascular disease and stroke in humans, but the cellular mechanisms of seaweed's effects are less known. In this review, we discuss the neuroprotective roles of seaweed phytochemicals in various models of cerebral ischemia. We further describe the potential cellular mechanisms such as the effect of seaweed phytochemicals in ischemia-mediated oxidative stress and inflammation. Additional preclinical studies are needed to develop effective dietary interventions for the prevention of ischemia-associated brain damage in humans.

A Qualitative Analysis of Experiences With Food-Related Activities Among People Living With Parkinson Disease and Their Care-Partners

Objectives: The purpose of this qualitative study was to explore factors associated with the ability of people with PD to perform food-related activities (FRAs). Methods: Eleven dyads, older adults with Parkinson disease (PD) and their care-partners (n = 22), completed virtual semi-structured interviews guided by the Social Cognitive Theory (SCT) that were independently analyzed by two coders via directed content analysis. Results: The following themes were identified-(1) Personal: perception of a healthy diet, perception of how nutrition influences PD, confidence in following a healthy diet, and barriers to performing FRA; (2) Environmental: previous sources of nutrition information and willingness to changing their diet with a registered dietitian; and (3) Behavioral: modifications to FRA due to food-medication interactions, and skills necessary to maintain a healthy diet. Discussion: Findings from this study highlight the need for nutrition intervention research to inform evidence-based guidelines in order to provide tailored education for people with PD and care-partners.

A Mixed Methods Exploration of the Impact of the COVID-19 Pandemic on Food-Related Activities and Diet Quality in People with Parkinson Disease

OBJECTIVE

The purpose of this mixed methods study was to explore the impact of COVID-19 on the ability of people with Parkinson disease (PwPs) and their care-partners to perform food-related activities (FRA) and PwPs' overall diet quality.

METHODS

Using a convergent parallel mixed methods design, PwPs and their care-partners completed virtual dyadic semi-structured interviews about their FRA during the COVID-19 pandemic. PwPs completed Food Frequency Questionnaires (FFQ) to quantify their dietary intake in the previous 12 months. Qualitative data were analyzed by two coders using thematic analysis, and quantitative data from FFQs were descriptively analyzed to calculate diet quality scores.

RESULTS

Eleven dyadic interviews revealed the following key themes: cooking more at home; changes with grocery shopping; less meals with non-household members. These changes were described to increase the care-partners' responsibilities and overall burden. Diet scores among PwPs were 73.0 ± 6.3 for the Healthy Eating Index 2015 (scale of 0-100), 29.2 ± 6.6 for the Mediterranean diet (scale of 0-55), and 10.4 ± 1.8 for the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet (scale 0-15).

CONCLUSIONS

Diet scores revealed that PwPs consumed a high-quality diet during the pandemic. Findings from this study highlight the need for tailored nutrition education to support PwPs' care-partners.

Changes in Cardiometabolic Risk Among Older Adults with Obesity: An Ancillary Analysis of a Randomized Controlled Trial Investigating Exercise Plus Weight Maintenance and Exercise Plus Intentional Weight Loss by Caloric Restriction

BACKGROUND

Obesity imposes risk to cardiometabolic health; however, intentional weight loss among older adults with obesity remains controversial.

OBJECTIVE

To explore the influence of exercise plus weight maintenance and exercise plus intentional weight loss by caloric restriction on changes in cardiometabolic risk among older adults with obesity assessed by four risk-scoring tools.

DESIGN

Using longitudinal data from the Calorie Restriction and Changes in Body Composition, Disease, Function, and Quality of Life in Older Adults study (CROSSROADS) (ClinicalTrials.gov identifier: NCT00955903; May 2009 to October 2014), scores were calculated using baseline and 12-month data according to criteria from the International Diabetes Federation, National Cholesterol Education Program's Adult Treatment Panel, Framingham Risk Score, and Cardiometabolic Disease Staging.

PARTICIPANTS AND SETTING

Participants (39% men, 23% African American, aged 70.2 ± 4.7 years) were randomized to exercise (n = 48), exercise plus nutrient-dense weight maintenance diet (n = 44), or exercise plus weight loss by moderate caloric restriction (n = 42).

MAIN OUTCOME MEASURES

To evaluate effects of exercise plus weight maintenance and exercise plus intentional weight loss on changes in cardiometabolic risk.

STATISTICAL ANALYSES PERFORMED

Generalized estimating equations were used to assess changes in risk with ethnicity, biological sex, and age as covariates.

RESULTS

Group-time interaction was only significant for Framingham and Cardiometabolic Disease Staging (P = 0.005 and 0.041, respectively). Upon post hoc analysis, significant within-group improvements in Framingham scores were observed for exercise plus weight maintenance (P < 0.001; r = -1.682) and exercise plus weight loss (P = 0.020; r = -0.881). In analysis of between-group differences in Framingham scores, significant decreases were observed in the exercise plus weight maintenance group (P = 0.001; r = -1.723) compared with the exercise group. For Cardiometabolic Disease Staging, the exercise plus weight loss group had significant within-group improvements (P = 0.023; r = -0.102). For between-group differences in Cardiometabolic Disease Staging, the exercise plus weight loss group showed significant risk reduction (P = 0.012; r = -0.142) compared with the exercise group.

CONCLUSIONS

Among risk scores evaluated, Framingham and Cardiometabolic Disease Staging showed significantly greater sensitivity to change in cardiometabolic risk. Older adults with obesity can significantly lower cardiometabolic risk through exercise plus weight maintenance or exercise plus weight loss by moderate caloric restriction.

Daily 100% watermelon juice consumption and vascular function among postmenopausal women: A randomized controlled trial

BACKGROUND AND AIMS

Watermelon juice is a rich food source of cardioprotective compounds such as arginine, citrulline, and lycopene. Preventative interventions are warranted as risk of cardiovascular disease increases among women after menopause, and age alone is an independent risk factor for vascular dysfunction. Thus, this study evaluated the effects of 100% watermelon juice on measures of vascular function.

METHODS AND RESULTS

In this randomized, double-blind, placebo-controlled, crossover trial, 21 healthy postmenopausal women were randomized to consume two 360 mL servings of 100% watermelon juice per day or an isocaloric placebo for four weeks. Following a two-week washout period, they consumed the other beverage for an additional four weeks. Before and after each treatment arm, a fasting blood sample was taken for measurement of serum arginine, citrulline, lycopene, glucose, and insulin. Assessments of vascular function included pulse pressure, pulse wave velocity, 24-h ambulatory blood pressure, and flow-mediated dilation. General linear mixed models with intent-to-treat analyses were used to examine the effects of the intervention. Despite a significant treatment effect for circulating lycopene (p = 0.002), no changes in arginine, citrulline, or any vascular measures were observed. Although the juice intervention resulted in a slight but significant increase in fasting serum glucose (p = 0.001), changes in glucose homeostasis were not clinically significant.

CONCLUSION

In contrast to findings from previous studies in younger adults and those with pre-existing hypertension, measures of vascular function in this cohort of healthy postmenopausal women were not impacted by supplemental watermelon juice. CLINICALTRIALS.

GOV IDENTIFIER

NCT03626168.

"If They Don't Like You, They Are Not Going to Eat for You": Individual and Interpersonal Factors Affecting Certified Nursing Assistants' Ability to Provide Mealtime Assistance to Residents With Dementia

BACKGROUND AND OBJECTIVES

In long-term care facilities in the United States, certified nursing assistants (CNAs) provide mealtime assistance to residents with dementia, a task that substantially increases caregiver burden due to the time and attention required. The aim of this qualitative study was to explore the individual and interpersonal barriers and facilitators CNAs experience when providing mealtime assistance to residents with dementia.

RESEARCH DESIGN AND METHODS

Focus group questions were developed based on the corresponding levels of the Social Ecological Model. Using purposive sampling, 9 focus groups were conducted with 53 CNAs who had at least 1 year of experience as a CNA working with older adults. Focus groups were audio-recorded and transcribed verbatim. Data were analyzed using the directed content analysis approach.

RESULTS

CNAs reported individual skills, training, and personal characteristics that affected their ability to provide mealtime assistance. At the interpersonal level, CNAs identified their relationships with residents, residents' family members, and other health care professionals as factors that affect their ability to provide mealtime assistance.

DISCUSSION AND IMPLICATIONS

These findings provide evidence for strategies that administrators can utilize to reduce caregiver burden by improving the mealtime experience. First, CNAs need adequate training, particularly to develop communication skills. Developing verbal communication skills may improve interpersonal relationships between CNAs and residents' family members and other coworkers. Developing nonverbal communication skills may foster an improved relationship between CNAs and their residents with dementia. Future research should evaluate interventions that seek to improve these skills to determine their impact on the mealtime experience.

Visceral adiposity index and its association with Dietary Approaches to Stop Hypertension (DASH) diet scores among older adults: National Health and Nutrition Examination Surveys 2011-2014

BACKGROUND & AIMS

The visceral adiposity index (VAI) has been shown to be a reliable estimate of visceral adiposity, but little is known about its association with specific dietary patterns such as the Dietary Approaches to Stop Hypertension (DASH) diet, particularly in older adults. Many studies have shown the DASH diet to be beneficial for cardiometabolic health. The purpose of this study was to investigate the relationship between DASH diet scores and the VAI in older adults using a nationally representative dataset.

METHODS

Using the National Health and Nutrition Examination Surveys (NHANES) from 2011 to 2014, data from 508 community-dwelling older adults were examined, and dietary intake was evaluated using the Dixon's DASH diet index. Using multiple linear regression analysis, the relationship between VAI and DASH diet score was assessed while controlling for demographic variables.

RESULTS

Participants' average DASH diet score was 2.41 (SE = 0.07), and the average VAI was 1.55 (SE = 0.08). The results suggest a significant inverse relationship between the DASH diet and VAI (β = -0.19, t = -2.73, p = 0.009).

CONCLUSIONS

Results of this study suggest that protective properties of the DASH diet pattern may be due in part to its inverse relationship with visceral adiposity. This information supports practitioners' use of the VAI with older adults in addition to providing nutrition counseling with the DASH diet to reduce patients' cardiometabolic risk.

100% Watermelon Juice as a Food-First Intervention to Improve Cognitive Function: Ancillary Findings from a Randomized Controlled Trial

Lycopene exhibits neuroprotective properties due to its antioxidant and anti-inflammatory functionality. As watermelon is a rich source of lycopene, pasteurized watermelon juice provides lycopene in its most bioavailable form. This study examined relationships between circulating lycopene, cognitive performance, and biomarkers of oxidative stress and inflammation in response to pasteurized 100% watermelon juice supplementation. A placebo-controlled, randomized, double-blind, crossover trial was conducted with postmenopausal women (n = 16, 60 + 4.1 years). Participants consumed two 360 mL servings of pasteurized 100% watermelon juice or a placebo beverage for 4 weeks. Fasting blood samples were collected, and cognitive tests were administered to assess various neurocognitive domains. Statistical analyses included mixed models and Spearman correlations. Serum lycopene exhibited a significant treatment effect (p = 0.002) with a mean increase of 81%. However, this increase was not associated with changes in oxidative stress, inflammation, or cognitive function. Additional research is warranted to determine dose-durational effects for promoting cognition.

Variation of Serum Lycopene in Response to 100% Watermelon Juice: An Exploratory Analysis of Genetic Variants in a Randomized Controlled Crossover Study

BACKGROUND

Watermelon, a rich source of lycopene, has garnered attention for cardioprotective effects including cholesterol reduction and promotion of redox balance. It is unknown whether 100% watermelon juice may represent a food-first approach to confer cardioprotective benefits of lycopene.

OBJECTIVES

This study examined influences of 100% watermelon juice on serum lycopene, lipids, and antioxidant capacity. Secondly, the study explored genetic influences on lycopene metabolism and bioavailability.

METHODS

A placebo-controlled, randomized, double-blind, crossover trial with postmenopausal women (n = 16, mean ± SD age: 60 ± 4.1 y) assessed effects of 100% watermelon juice on mechanistic and clinical outcomes influencing vascular function. Participants maintained low-lycopene diets for a 1-wk run-in period and throughout the study. Morning and evening consumption of 100% watermelon juice provided a daily dose of 14.4 ± 0.34 mg lycopene. Study arms of 4 wk were separated by a 2-wk washout period. Saliva was collected for genetic analysis of single nucleotide polymorphisms, and fasting blood samples were taken pre- and post-study arms. Statistical analyses included mixed models, linear regression, and nonparametric tests.

RESULTS

Serum lycopene exhibited a significant treatment effect (P = 0.002) along with notable interindividual responses; however, significant improvements in serum lipids or antioxidant capacity were not observed. Genetic variant rs6564851 in the β-carotene 15,15'-oxygenase-1 (BCO1) gene was associated with changes in lycopene such that TT homozygotes exhibited a significantly greater increase (β ± SE: 13.4 ± 1.6, P = 1.4 × 10-06).

CONCLUSIONS

Watermelon juice supplementation did not result in improvements in serum lipids or antioxidant capacity; however, results support findings in which watermelon juice significantly, yet differentially, increased circulating lycopene. Genetics appears to explain some of the variability. Given that dose has been shown to overcome individual responsiveness to lycopene interventions, future investigations with varying doses of lycopene-rich foods would be strengthened by genotyping so as to establish personalized nutrition recommendations.This trial was registered at clinicaltrials.gov as NCT03626168.

Dietary Antioxidants and Parkinson's Disease

Parkinson’s disease (PD) is a neurodegenerative disorder caused by the depletion of dopaminergic neurons in the basal ganglia, the movement center of the brain. Approximately 60,000 people are diagnosed with PD in the United States each year. Although the direct cause of PD can vary, accumulation of oxidative stress-induced neuronal damage due to increased production of reactive oxygen species (ROS) or impaired intracellular antioxidant defenses invariably occurs at the cellular levels. Pharmaceuticals such as dopaminergic prodrugs and agonists can alleviate some of the symptoms of PD. Currently, however, there is no treatment to halt the progression of PD pathology. Due to the nature of PD, a long and progressive neurodegenerative process, strategies to prevent or delay PD pathology may be well suited to lifestyle changes like dietary modification with antioxidant-rich foods to improve intracellular redox homeostasis. In this review, we discuss cellular and genetic factors that increase oxidative stress in PD. We also discuss neuroprotective roles of dietary antioxidants including vitamin C, vitamin E, carotenoids, selenium, and polyphenols along with their potential mechanisms to alleviate PD pathology.

Classification of obesity, cardiometabolic risk, and metabolic syndrome in adults with spinal cord injury

Objective: To describe and compare (1) classification of obesity using clinical proxies of body composition that are easily accessible in the outpatient clinic setting, (2) cardiometabolic risk using existing screening tools and staging systems, and (3) the presence of metabolic syndrome (MetS) using four commonly-used definitions in adults with spinal cord injury (SCI). Design: Retrospective chart review Setting: Outpatient Veterans Affairs (VA) SCI Annual Evaluation Clinic Participants: Patients who attended an annual evaluation appointment with demographic, anthropometric, and biochemical data documented in their medical records as part of routine medical care. Outcome measures: Obesity classification (body mass index, waist circumference, ideal body weight percentage), cardiometabolic risk scores (Framingham Risk Score, Cardiometabolic Disease Staging System, Edmonton Obesity Staging System), and MetS classification (using four commonly-used definitions) were described and compared. Results: Of the 155 veterans included in this analysis, 93% were considered "at risk" by at least one of the measurements studied. However, there was considerable variation between the different screening tools. The κ-agreement between various definitions of MetS ranged from fair to moderate. Conclusion: Screening tools that were developed for the non-SCI population produced variable assessments of risk when applied to veterans with SCI. Due to the fair to moderate inter-rater agreement between MetS definitions, it is unknown which definition is superior to identify MetS in the SCI population. An SCI-specific screening tool is needed to accurately classify obesity, cardiometabolic risk, and MetS in order to provide timely education and intervention.

Dietetic Students' Perceived Facilitators, Barriers and Perceptions of Working with Older Adults: Implications for Curriculum Development

Objective: The purpose of this study was to explore dietetic students' facilitators, barriers, and perceptions of working with older adults.Method: A purposive sampling method was used to conduct individual, face-to-face-interviews with students majoring in human nutrition (n = 17). All interviews were audio recorded, transcribed verbatim, and coded using NVivo 11 software. A directed content analysis revealed the following themes under categories of (1) perception, (2) barriers, (3) facilitators, and (4) impact of experience.Results: For perception, students discussed older adults' positive and negative personality traits and their physical and cognitive deterioration. Such perception contributed to their view of barriers in interactions with older adults, which were both external and internal in nature. Students mentioned previous experience and knowledge about older adults as well as their own personalities served as major facilitators in interacting with older adults. Gaining experience working with older adults deepened students' understanding of and empathy for this population.Discussion: Findings offer insight into how to develop dietetic curricula to address students' perceptions and resulting barriers for training well-prepared registered dietitians motivated to serve the rapidly growing older adult population.

Dietary Supplement Use is High among Individuals with Parkinson Disease

OBJECTIVES

To assess the present use of dietary supplements among the Parkinson disease (PD) population and to determine which dietary supplements are most commonly taken.

METHODS

This cross-sectional study used an online questionnaire that was administered to individuals with PD via support group Web sites. Dietary supplement users also were asked whether they spoke with a healthcare professional about their supplement use.

RESULTS

Of the 205 respondents, 83.4% reported taking at least 1 dietary supplement. Although 94 different types of dietary supplements were identified, >50% of participants taking dietary supplements took multivitamins, vitamin D, and vitamin B₁₂ (52.6%, 74.3%, and 56.1%, respectively). Respondents reported taking coenzyme Q10, Mucuna pruriens, folate, vitamin B₁₂, vitamin B₆, melatonin, and N-acetylcysteine most commonly for PD. Among supplement users, 29.2% did not discuss their supplement use with a healthcare practitioner.

CONCLUSIONS

The results of this study demonstrate a high prevalence of dietary supplement use among individuals with PD, in addition to a wide variety of supplements being taken. This study's findings also indicate the need for better dialog between patients and healthcare practitioners regarding the use of dietary supplements.

Nutrition Provider Isolation Is Related to Increased Preference for Enteral Nutrition-Support in Patients With Advanced Dementia

BACKGROUND

Current guidelines advise against using enteral nutrition (EN) support for patients with advanced dementia (AD) because of negative outcomes. However, research suggests that some registered dietitian nutritionists (RDNs) in acute-care settings still recommend EN for this patient population. The purpose of this study was to identify workplace characteristics that influence the EN recommendations of acute-care RDNs who care for patients with AD.

METHODS

A random sample of 5000 RDNs in the United States were invited to participate in a web-based survey in which RDNs self-reported the likelihood that they would recommend EN for a patient with AD. Inclusion criteria specified that participants were at least 18 years of age, were an RDN in the United States, and currently provide nutrition care to older adults with dementia. χ² tests compared RDN recommendations by workplace characteristics. Logistic regression was used to determine factors associated with recommending EN for patients with AD.

RESULTS

Respondents included 204 acute-care RDNs. RDNs in rural or suburban locations were 2.4 times more likely to recommend EN compared with those in urban facilities (95% CI, 1.1-5.1). RDNs who were the only nutrition provider at their facility were 3.3 times more likely to recommend EN than those in facilities with multiple RDNs (95% CI, 1.4-7.9).

CONCLUSION

Acute-care RDNs who are isolated either in rural facilities or because they lack other RDN colleagues at their facility may benefit from targeted interventions to increase knowledge and promote adherence to evidence-based guidelines.

Watermelon Juice: a Novel Functional Food to Increase Circulating Lycopene in Older Adult Women

Because of accruing oxidative stress with advancing age, older adults may benefit from increased dietary intake of lycopene, a lipophilic carotenoid with potent antioxidant properties. Yet, intake of dietary lycopene as well as circulating lycopene levels are known to decrease with aging. Watermelon is one of the few food sources of dietary lycopene. Because heat treatment increases lycopene bioavailability, ingestion of watermelon in pasteurized juice form may be an optimal delivery vehicle to increase lycopene levels in older adults. However, due to its lipophilic nature, there are concerns that co-ingestion of dietary fat may be necessary for efficient intestinal absorption of lycopene. Thus, this feasibility study aimed to examine the effects of a one-time dose of 100% pasteurized watermelon juice on circulating lycopene concentrations of postmenopausal women after a 10-h overnight fast. Blood was sampled from eight women before and 2 h after ingestion of 360 ml of juice, and serum lycopene was measured by ultra-high performance liquid chromatography. Circulating lycopene levels increased by three-fold (p < 0.001) with increases observed for every participant. Results demonstrate that 100% watermelon juice is a palatable, effective means of increasing serum lycopene in older adult women, a group at risk for low carotenoid intake. Trial registration: Clinicaltrials.gov identifier: NCT03608254 .

Dietary Quality Assessed by the HEI-2010 and Biomarkers of Cardiometabolic Disease: An Exploratory Analysis

Objectives: This study explores relationships between cardiometabolic measures of antioxidant capacity or inflammation and diet quality assessed by the Healthy Eating Index (HEI)-2010 which measures conformity to Dietary Guidelines for Americans. This cross-sectional study was an ancillary analysis of baseline data for a randomized controlled trial with older adults at risk for cardiometabolic disease (ClinicalTrials.gov #NCT00955903). Methods: Community-dwelling older adults (n = 133, 49% male, 70.4 ± 4.8 years) with a body mass index of 30-40 kg/m² provided a fasted blood sample for measurement of antioxidant capacity, high-sensitivity C-reactive protein, tumor necrosis factor-alpha, and interleukin-6. Dietary data were generated from the mean of three 24-hour recalls. Results: After adjustment for potential confounders, HEI-2010 composite scores were not significantly associated with decreased inflammation or greater antioxidant capacity. In analysis of the 12 components composing the HEI-2010, significant positive association was observed between total dairy and total serum antioxidant capacity (0.043; 95% CI, 0.008-0.069). Significant associations observed in inflammatory markers were between total vegetable and tumor necrosis factor-alpha (-0.078; 95% CI, -0.151 to -0.005), sodium and interleukin-6 (0.091; 95% CI, 0.023-0.158), and scores for combined calories from solid fats, alcoholic beverages, and added sugars and interleukin-6 (0.139; 95% CI, 0.027-0.252). In models adjusting for HEI-2010 composite score when significant associations were observed between component scores and biomarkers, two of six associations were strengthened by adding the composite score as a potential confounder. Conclusions: Largely null findings along with those inconsistent with scientific expectations suggest caution in extrapolating adherence to the HEI-2010 with an individual's inflammatory or antioxidant status. Results merit additional investigation with other biomarkers of chronic disease and emphasis on dietary patterns given potential synergy within food combinations.

Practitioner Knowledge, Personal Values, and Work Setting Influence Registered Dietitians' Feeding Tube Recommendations for Patients With Advanced Dementia

BACKGROUND

Current guidelines discourage tube-feeding older adults with advanced dementia (AD), as this practice does not improve nutrition status or survival and decreases quality of life in these patients. Because registered dietitians (RDs) often provide feeding recommendations for patients with AD, this study aimed to identify factors that influenced RDs' feeding tube recommendations for older adults with AD.

METHODS

A random sample of RDs who work with older adults in the United States completed a validated, electronic survey. Logistic regression analysis was used to identify factors related to the likelihood of RDs recommending a feeding tube for patients with AD. Independent variables included participant demographics and the 6 subscales of the Attitudes Toward Tube-Feeding in Advanced Dementia Questionnaire, which measured individual and environmental influences on RDs' recommendations.

RESULTS

Among the 662 RDs who responded, 72.2% were unlikely to recommend a feeding tube in patients with AD, and 15.4% were likely to do so (with the remaining being "neutral"). Factors associated with avoiding recommending a feeding tube include significantly higher total knowledge [odds ratio (OR) = 1.47, 95% CI (1.30, 1.66)] and personal values scores [OR = 7.51, 95% CI (3.96, 14.24)] and employment in long-term care settings [OR 3.29, 95% CI (1.38, 7.80)].

CONCLUSION

In this survey, most RDs were likely to make recommendations that are consistent with current guidelines for tube feeding patients with AD. RDs who work outside the long-term care setting may benefit from additional training. Future research is needed to understand how personal values may influence recommendations.

The Attitudes Toward Tube-Feeding in Advanced Dementia (ATT-FAD) Questionnaire: A Valid and Reliable Tool

Registered Dietitians (RDs) should participate in interdisciplinary feeding discussions for patients with advanced dementia, but research on how RDs make such feeding recommendations is scarce. This study developed and validated a theory-based questionnaire to assess the knowledge, beliefs, and attitudes of RDs regarding feeding tube use among older adults with advanced dementia. The instrument was drafted based on the Social Ecological Model, and face and content validity were established through an expert panel review. Pilot testing with 70 RDs provided an initial measure of internal consistency reliability and reduced the number of items in the survey. Efficacy testing with 662 RDs allowed for a second analysis of internal consistency reliability and eliminated additional items. Construct validity was then established using validation by extreme groups and exploratory factor analysis, yielding six subscales, each with adequate internal consistency and test-retest correlation coefficients: (I) Total Knowledge, (II) Knowledge Self-Efficacy, (III) Religion/Spirituality/Culture, (IV) Personal Values, (V) Perceived Organization and Training, and (VI) Perceived Policy. The survey, based on the Social Ecological Model, was deemed a valid and reliable tool to assess RDs' knowledge and attitudes regarding feeding tube use among older adults with advanced dementia.

Comparison of segmental body composition estimated by bioelectrical impedance analysis and dual-energy X-ray absorptiometry

BACKGROUND & AIMS

Segmental body composition may be an important indicator of health and nutritional status in conditions where variations in fat and lean mass are frequently isolated to a particular body segment (e.g. paralysis, sarcopenia). Until recently, segment-specific body composition could only be assessed using invasive and expensive methods such as dual-energy x-ray absorptiometry (DXA), magnetic resonance imaging (MRI), or computed tomography (CT). Bioelectrical impedance analysis (BIA) may be a rapid, inexpensive alternative for assessing segmental composition, but it has not been fully validated for this purpose. The purpose of this study was to compare segmental estimates of lean and fat mass using BIA versus a criterion standard of DXA.

METHODS

A cross-sectional pilot study was conducted in n = 30 healthy adults. Outcome measures included total mass, fat mass and lean mass of arm, leg and trunk. Pearson correlation coefficients (r) and paired-samples t-tests (t) were used to assess relationships between each outcome as measured by BIA and DXA.

RESULTS

Although the methods were strongly correlated for all measures, (r > .87 for all segments) BIA routinely overestimated lean mass for arm and trunk (mean difference arm: 0.97 kg, p = .008; trunk: 5.58 kg, p < .0001); and underestimated fat mass for arm and leg (mean difference arm: 0.42 kg, p < .0001; leg: 1.94 kg p < .0001). BIA overestimated total body lean mass in 93% of participants and underestimated total body fat mass in 90% of participants.

CONCLUSIONS

Significant discrepancies were noted between DXA and BIA in all body segments. Further research is needed to refine BIA methods for segmental composition estimates in heterogeneous samples and disease-specific populations before this methods can be used reliably in a clinical setting.

Intention of Older Women to Consume 100% Watermelon Juice for Vascular Health: An Application of Theory of Planned Behavior

To strengthen randomized controlled trials (RCT) evaluating the efficacy of 100% watermelon juice on vascular function of older women, theory-driven behavioral analysis as well as comparative sensory analysis of the intervention and placebo were conducted. The Theory of Planned Behavior was adopted to assess psychosocial determinants of intention to consume watermelon juice. Sensory attributes were assessed utilizing hedonic scales. Analysis included Structural Equation Modeling with maximum likelihood. The measurement model provided a good fit (x² = 70.22, df = 38; RMSEA = 0.07, CFI = 0.98; NFI = 0.95). Attitude (γ = 0.36), subjective norm (γ = 0.43), and perceived behavioral control (γ = 0.21,) were significant predictors (p < 0.001) of intention. Participants identified no significant differences in sensorial attributes between beverages, thereby minimizing sensory bias and discrimination. Similar approaches may help other RCT investigating novel foods and bioactive compounds bridge gaps between efficacy and effectiveness.

Oral Supplementation with Beta-Hydroxy-Beta-Methylbutyrate, Arginine, and Glutamine Improves Lean Body Mass in Healthy Older Adults

Oral intake of beta-hydroxy-beta-methylbutyrate (HMB), arginine, and glutamine may ameliorate muscle loss by stimulating protein synthesis and decreasing protein degradation while simultaneously decreasing inflammation. Previous studies provide evidence for improvement in body composition with dietary supplementation of these ingredients among patients with muscle-wasting diseases. The objectives of this study were to examine the effects of this amino acid mixture on lean body mass, muscle volume, and physical function among healthy older adults. Thirty-one community-dwelling men and women, aged 65-89 years, were randomized to either two oral doses of the amino acid supplement (totaling 3 g HMB, 14 g arginine, 14 g glutamine) or placebo daily for six months. At baseline and month six, lean body mass was measured by air displacement plethysmography, dual-energy X-ray absorptiometry (DXA), and four-compartment model. Muscle volume of quadriceps was quantified by magnetic resonance imaging (MRI), and participants performed a battery of tests to assess physical function. As compared to the placebo group, the treatment group exhibited improvement in a timed stair climb (p =.016) as well as significant increases in lean body mass by all methods of assessment (p <.05). Regional analysis by DXA revealed increased arm lean mass in the supplement group only (p =.035). However, no change was observed in MRI-derived quadriceps volume. Dietary supplementation with HMB, arginine, and glutamine improved total body lean mass among a small sample of healthy older adults. Further research is indicated to elucidate mechanisms of action and to determine whether supplementation may benefit frail elders. Registered under ClinicalTrials.gov identifier no. NCT01057082.

Validation of a Screening Tool to Identify Undernutrition in Ambulatory Patients With Liver Cirrhosis

BACKGROUND

The prevalence of chronic liver disease is increasing in the United States. Malnutrition is common as liver disease progresses. However, an accepted method to screen these patients for malnutrition is lacking. The 6-question undernutrition screening tool was developed for professionals without nutrition training to identify a decline in the nutrition status of patients with liver cirrhosis. A 3-phase validation study was completed to assess face, content, and clinical validity of the screening tool in ambulatory patients with liver cirrhosis.

METHODS

In phase I, face validity was determined by surveying 13 liver disease professionals. In phase II, content validity was assessed by surveying 12 registered dietitians who specialize in liver disease. In phase III, a cross-sectional investigation was completed to compare the agreement between the undernutrition screening tool and nutrition assessment by a registered dietitian (RD).

RESULTS

Twenty-two patients with a diagnosis of liver cirrhosis participated in phase III of the investigation. The RD assessment identified undernutrition in 82% of patients (95% CI, 60%-95%). The κ statistic indicated a fair agreement between the screening tool and RD assessment. Sensitivity and specificity of the tool were 72% and 75%, respectively, and positive predictive value was 93%.

CONCLUSIONS

Feedback from phase I, II, and III indicate that the undernutrition screening tool is simple, is easy to use, and measures the constructs that have the strongest link with undernutrition in liver disease. Additional minor adjustments to the screening tool and a multicenter investigation are indicated to confirm clinical effectiveness and cross-validity of the tool.

Cardiorespiratory fitness in older adult women: relationships with serum 25-hydroxyvitamin D

Previous studies suggest that circulating 25(OH)D may favorably influence cardiorespiratory fitness and fat oxidation. However, these relationships have not been examined in older adult women of different ethnic groups. The objectives of this study were to determine whether serum 25(OH)D is related to cardiovascular fitness (VO2max) in sedentary women ages ≥60 years and to determine whether these associations differ between African Americans (AA) and European Americans (EA). A secondary aim was to determine whether serum 25(OH)D is correlated with respiratory quotient (RQ) during submaximal exercise. This cross-sectional analysis included 67 AA and EA women ages 60-74 years. VO2max was measured by a modified Bruce graded treadmill protocol, and measurements were adjusted for percent fat and lean body mass assessed by air displacement plethysmography. Indirect calorimetry was used to measure RQ at rest and during four submaximal exercise tests. Fasting blood samples were obtained to quantify serum 25(OH)D. Serum 25(OH)D was associated with VO2max (ml/kg LBM/min) independent of percent body fat (r = 0.316, p = 0.010). However, subgroup analysis revealed that this relationship was specific to AA (r = 0.727, p = 0.005 for AA; r = 0.064, p = 0.643 for EA). In all subjects combined, 25(OH)D was inversely correlated (p < 0.01) with all measures of submaximal RQ. Higher serum 25(OH)D was associated with greater cardiorespiratory fitness in older adult AA women. Among both AA and EA, inverse associations between serum 25(OH)D and RQ suggest that women with higher levels of circulating vitamin D also demonstrated greater fat oxidation during submaximal exercise.

Return of hunger following a relatively high carbohydrate breakfast is associated with earlier recorded glucose peak and nadir

The aim of this study is to test the hypothesis that a breakfast meal with high carbohydrate/low fat results in an earlier increase in postprandial glucose and insulin, a greater decrease below baseline in postprandial glucose, and an earlier return of appetite, compared with a low carbohydrate/high fat meal. Overweight but otherwise healthy adults (n = 64) were maintained on one of two eucaloric diets: high carbohydrate/low fat (HC/LF; 55:27:18% kcals from carbohydrate:fat:protein) versus low carbohydrate/high fat (LC/HF; 43:39:18% kcals from carbohydrate:fat:protein). After 4 weeks of acclimation to the diets, participants underwent a meal test during which circulating glucose and insulin and self-reported hunger and fullness, were measured before and after consumption of breakfast from their assigned diets. The LC/HF meal resulted in a later time at the highest and lowest recorded glucose, higher glucose concentrations at 3 and 4 hours post meal, and lower insulin incremental area under the curve. Participants consuming the LC/HF meal reported lower appetite 3 and 4 hours following the meal, a response that was associated with the timing of the highest and lowest recorded glucose. Modest increases in meal carbohydrate content at the expense of fat content may facilitate weight gain over the long-term by contributing to an earlier rise and fall of postprandial glucose concentrations and an earlier return of appetite.

2013 environmental health legislation

The NEHA Government Affairs program has a long and productive association with the National Conference of State Legislatures (NCSL). The organizations have worked together on any number of legislative and policy areas that directly impact the environmental health profession. One of the keys to the successes of the NEHA/NCSL collaboration has been the recognition of the fact that often some of the most significant legislation and policy initiatives related to environmental public health occur in state legislatures. The states have, in a very real sense, been the innovators in developing new programs and practices. In recognition of this fact, we have asked NCSL to provide occasional overviews of state environmental public health legislative activity, covering topics that are of the most pressing public concern. Doug Farquhar, program director for NCSI's Environmental Health Program, has worked with NCSL since 1990. Mr. Farquhar directs development, management, and research for the Environmental Health Program. These projects encompass consultation and policy analysis of state and federal policies and statutes, regulations, and programs regarding environmental and related topics for state legislatures and administrative programs. Amy Ellis is a law clerk for NCSL within the Environment, Energy, and Transportation Group. As a law clerk she has researched a wide variety of environmental health policies. She is expected to obtain her JD from the University of Colorado Law School in 2015.

Effects of diet macronutrient composition on body composition and fat distribution during weight maintenance and weight loss

OBJECTIVE

Qualitative aspects of diet may affect body composition and propensity for weight gain or loss. We tested the hypothesis that consumption of a relatively low glycemic load (GL) diet would reduce total and visceral adipose tissue under both eucaloric and hypocaloric conditions.

DESIGN AND METHODS

Participants were 69 healthy overweight men and women. Body composition was assessed by DXA and fat distribution by CT scan at baseline, after 8 weeks of a eucaloric diet intervention, and after 8 weeks of a hypocaloric (1000 kcal/day deficit) diet intervention. Participants were provided all food for both phases, and randomized to either a low GL diet (<45 points per 1000 kcal; n = 40) or high GL diet (>75 points per 1000 kcal, n = 29).

RESULTS

After the eucaloric phase, participants who consumed the low GL diet had 11% less intra-abdominal fat (IAAT) than those who consumed the high GL diet (P < 0.05, adjusted for total fat mass and baseline IAAT). Participants lost an average of 5.8 kg during the hypocaloric phase, with no differences in the amount of weight loss with diet assignment (P = 0.39). Following weight loss, participants who consumed the low GL diet had 4.4% less total fat mass than those who consumed the high GL diet (P < 0.05, adjusted for lean mass and baseline fat mass).

CONCLUSIONS

Consumption of a relatively low GL diet may affect energy partitioning, both inducing reduction in IAAT independent of weight change, and enhancing loss of fat relative to lean mass during weight loss.

Effects of habitual diet on ethnic differences in serum total ghrelin

Ghrelin, an orexigenic hormone, may be involved in the etiology of obesity. African Americans (AA) experience higher obesity rates than European Americans (EA), but it is unclear whether ghrelin differs with ethnicity. This study was designed to compare ghrelin concentrations between overweight AA and EA adults in a post absorptive state, in response to a standard meal, and after 8-week habituation to diets of differing macronutrient profiles. Sixty-one overweight men and women (31 EA and 30 AA) were assigned to either a higher-carbohydrate/lower-fat diet (55% CHO, 18% PRO, 27% FAT) or a lower-carbohydrate/higher-fat diet (43% CHO, 18% PRO, 39% FAT) for 8 weeks. At baseline and week 8, participants ingested a standard liquid mixed meal. Blood was sampled before the meal and serially after ingestion to measure total ghrelin and insulin. Hunger was assessed with a visual analog scale. Composite scores for ghrelin, insulin, and hunger were calculated as area under the curve (AUC), and ghrelin suppression was calculated as the change from fasting concentration. Fasting ghrelin and ghrelin AUC were higher among EA at baseline and week 8 (p < 0.001), and these differences were not affected by diet habituation. Despite greater postprandial ghrelin suppression, EA displayed greater hunger immediately following the test meal (p < 0.05). Overweight EA displayed higher circulating ghrelin and greater ghrelin suppression compared to AA. Further study is warranted to explore the physiological basis for these ethnic differences and to determine whether they may relate to higher obesity rates among AA.

Race differences in the association of oxidative stress with insulin sensitivity in African- and European-American women

Excessive metabolism of glucose and/or fatty acids may impair insulin signaling by increasing oxidative stress. The objective of this study was to examine the association between insulin sensitivity and protein carbonyls, a systemic marker of oxidative stress, in healthy, nondiabetic women, and to determine if the relationship differed with race. Subjects were 25 African-Americans (AA, BMI 28.4 ± 6.2 kg/m(2), range 18.8-42.6 kg/m(2); age 33.1 ± 13.5 years, range 18-58 years) and 28 European-Americans (EA, BMI 26.2 ± 5.9 kg/m(2), range 18.7-48.4 kg/m(2); age 31.6 ± 12.4 years, range 19-58 years). Insulin sensitivity was determined using an intravenous glucose tolerance test incorporating [6,6-(2)H(2)]-glucose, and a two-compartment mathematical model. Multiple linear regression results indicated that insulin sensitivity was inversely associated with protein carbonyls in AA (standardized regression coefficient -0.47, P < 0.05) but not EA (0.01, P = 0.945), after adjusting for %body fat. In contrast, %body fat was significantly and positively associated with insulin sensitivity in EA (-0.54, P < 0.01) but not AA (-0.24, P = 0.196). Protein carbonyls were associated with free fatty acids (FFA) in AA (r = 0.58, P < 0.01) but not EA (r = -0.11, P = 0.59). When subjects were divided based on median levels of fasting glucose and FFA, those with higher glucose/FFA concentrations had a significantly greater concentration of circulating protein carbonyls compared to those with lower glucose/FFA concentrations (P < 0.05). These results suggest that oxidative stress independently contributes to insulin sensitivity among AA women. Further, this association in AA may be mediated by circulating FFA and/or glucose.

Ethnic differences in glucose disposal, hepatic insulin sensitivity, and endogenous glucose production among African American and European American women

Intravenous glucose tolerance tests have demonstrated lower whole-body insulin sensitivity (S(I)) among African Americans (AA) compared with European Americans (EA). Whole-body S(I) represents both insulin-stimulated glucose disposal, primarily by skeletal muscle, and insulin's suppression of endogenous glucose production (EGP) by liver. A mathematical model was recently introduced that allows for distinction between disposal and hepatic S(I). The purpose of this study was to examine specific indexes of S(I) among AA and EA women to determine whether lower whole-body S(I) in AA may be attributed to insulin action at muscle, liver, or both. Participants were 53 nondiabetic, premenopausal AA and EA women. Profiles of EGP and indexes of Disposal S(I) and Hepatic S(I) were calculated by mathematical modeling and incorporation of a stable isotope tracer ([6,6-(2)H(2)]glucose) into the intravenous glucose tolerance test. Body composition was assessed by dual-energy x-ray absorptiometry. After adjustment for percentage fat, both Disposal S(I) and Hepatic S(I) were lower among AA (P = .009 for both). Time profiles for serum insulin and EGP revealed higher peak insulin response and corresponding lower EGP among AA women compared with EA. Indexes from a recently introduced mathematical model suggest that lower whole-body S(I) among nondiabetic AA women is due to both hepatic and peripheral components. Despite lower Hepatic S(I), AA displayed lower EGP, resulting from higher postchallenge insulin levels. Future research is needed to determine the physiological basis of lower insulin sensitivity among AA and its implications for type 2 diabetes mellitus risk.

A theoretically based Behavioral Nutrition Intervention for Community Elders at high risk: the B-NICE randomized controlled clinical trial

We conducted a study designed to evaluate the efficacy and feasibility of a multilevel self-management intervention to improve nutritional intake in a group of older adults receiving Medicare home health services who were at especially high risk for experiencing undernutrition. The Behavioral Nutrition Intervention for Community Elders (B-NICE) trial used a prospective randomized controlled design to determine whether individually tailored counseling focused on social and behavioral aspects of eating resulted in increased caloric intake and improved nutrition-related health outcomes in a high-risk population of older adults. The study was guided by the theoretical approaches of the Ecological Model and Social Cognitive Theory. The development and implementation of the B-NICE protocol, including the theoretical framework, methodology, specific elements of the behavioral intervention, and assurances of the treatment fidelity, as well as the health policy implications of the trial results, are presented in this article.

A higher-carbohydrate, lower-fat diet reduces fasting glucose concentration and improves β-cell function in individuals with impaired fasting glucose

The objective was to examine the effects of diet macronutrient composition on insulin sensitivity, fasting glucose, and β-cell response to glucose. Participants were 42 normal glucose-tolerant (NGT; fasting glucose <100 mg/dL) and 27 impaired fasting glucose (IFG), healthy, overweight/obese (body mass index, 32.5 ± 4.2 kg/m(2)) men and women. For 8 weeks, participants were provided with eucaloric diets, either higher carbohydrate/lower fat (55% carbohydrate, 18% protein, 27% fat) or lower carbohydrate/higher fat (43:18:39). Insulin sensitivity and β-cell response to glucose (basal, dynamic [PhiD], and static) were calculated by mathematical modeling using glucose, insulin, and C-peptide data obtained during a liquid meal tolerance test. After 8 weeks, NGT on the higher-carbohydrate/lower-fat diet had higher insulin sensitivity than NGT on the lower-carbohydrate/higher fat diet; this pattern was not observed among IFG. After 8 weeks, IFG on the higher-carbohydrate/lower-fat diet had lower fasting glucose and higher PhiD than IFG on the lower-carbohydrate/higher-fat diet; this pattern was not observed among NGT. Within IFG, fasting glucose at baseline and the change in fasting glucose over the intervention were inversely associated with baseline PhiD (-0.40, P < .05) and the change in PhiD (-0.42, P < .05), respectively. Eight weeks of a higher-carbohydrate/lower-fat diet resulted in higher insulin sensitivity in healthy, NGT, overweight/obese individuals, and lower fasting glucose and greater glucose-stimulated insulin secretion in individuals with IFG. If confirmed, these results may have an impact on dietary recommendations for overweight individuals with and without IFG.

Circulating ghrelin and GLP-1 are not affected by habitual diet

BACKGROUND

Ghrelin and glucagon-like peptide-1 (GLP-1) are gut hormones known to induce hunger and satiety, respectively. Current knowledge about the effects of different macronutrients on circulating ghrelin and GLP-1 comes mainly from acute test meals, whereas little is known about the effects of chronic dietary intake on gut hormone secretion. This study was designed to examine whether 8-week habituation to diets with different percentages of carbohydrate and fat would affect serum ghrelin, GLP-1, and subjective hunger in a postabsorptive state and in response to a standard liquid mixed meal.

METHODS

Sixty-one overweight men and women were provided all food for 8 weeks of either a higher-carbohydrate/lower-fat diet (High-CHO/Low-FAT; 55% CHO, 18% PRO, 27% FAT) or a lower-carbohydrate/higher-fat diet (Low-CHO/High-FAT; 43% CHO, 18% PRO, 39% FAT). After overnight fasts at baseline and week 8, participants consumed a standard liquid meal (7 kcals/kg, 58.6% CHO, 17.4% PRO, 24% FAT). Blood was sampled before the meal and at 15, 60, 90, 120, 180, and 240 min to determine total serum ghrelin and active GLP-1. Hunger was assessed by a visual analog scale. Mixed models were used to evaluate whether the temporal patterns of total serum ghrelin and active GLP-1 differed with diet.

RESULTS

Although both diet groups reported greater hunger after 8 weeks (p=0.03), circulating ghrelin and GLP-1 were not affected by acclimation to different macronutrients.

CONCLUSION

Habituation to different diets does not appear to influence fasting ghrelin, fasting GLP-1, or responses of these gut hormones to a standard meal.

Higher postprandial serum ghrelin among African-American girls before puberty

OBJECTIVE

Recent reports suggest that ghrelin regulation may differ by ethnicity and age. This study was designed to examine circulating ghrelin among overweight female African Americans across different age groups.

METHODS

Eleven overweight peripubertal girls, 17 overweight pubertal girls, and a control group of 18 overweight African-American premenopausal women ingested a standard liquid meal after an overnight fast. Blood samples were obtained before the meal and for 4 h postchallenge. Participants rated appetite by a visual analog scale.

RESULTS

Peripubertal girls demonstrated higher postprandial ghrelin and lesser ghrelin suppression compared with adults (p < 0.05), corresponding with greater desire to eat across the test period (p = 0.017). Fasting ghrelin tended to be inversely related to fasting estradiol (r = -0.264, p = 0.076).

CONCLUSION

Compared with overweight African-American women, peripubertal girls had higher ghrelin as well as greater appetite after a standard meal. These results may suggest a dysregulation in ghrelin reflective of demands of growth.

Which equation best predicts energy expenditure in amyotrophic lateral sclerosis?

OBJECTIVE

The purpose of this study was to compare measured resting energy expenditure (REE) with estimates from three common prediction equations with the goal of determining which equation best estimates REE in amyotrophic lateral sclerosis (ALS).

DESIGN

Cross-sectional measurements of REE from indirect calorimetry were compared to calculations from the Harris Benedict, Mifflin-St Jeor, and Ireton-Jones equations. Additional measurements to identify predictors of REE included pulmonary function tests, fat-free mass by bioelectrical impedance, and anthropometrics.

SUBJECTS/SETTING

Participants were 56 men and women with ALS. For comparison, subjects were categorized by disease progression into three groups.

STATISTICAL ANALYSES

Pearson correlations and paired t tests were used to compare measured REE with predicted REE from each equation, and the accuracy of each equation was quantified by the root mean squared prediction error and the percentage of REE estimates within 10% of measured values. Bias for each equation was calculated as the mean percentage difference between calculated and measured REE. Multiple linear regression was used to determine the best predictor variables for REE.

RESULTS

Across the disease spectrum, the Harris Benedict and Mifflin-St Jeor equations provided clinically acceptable estimates of REE, whereas the Ireton-Jones equations consistently overestimated REE. The best predictors of REE among this cohort were fat-free mass, sex, and age.

CONCLUSIONS

When estimating energy requirements for patients with ALS, clinicians should choose prediction equations that incorporate sex and age as predictor variables, such as the Harris Benedict and Mifflin-St Jeor equations.

Dietary macronutrient composition affects β cell responsiveness but not insulin sensitivity

BACKGROUND

Altering dietary carbohydrate or fat content may have chronic effects on insulin secretion and sensitivity, which may vary with individual metabolic phenotype.

OBJECTIVE

The objective was to evaluate the contribution of tightly controlled diets differing in carbohydrate and fat content for 8 wk to insulin sensitivity and β cell responsiveness and whether effects of diet would vary with race, free-living diet, or insulin response.

DESIGN

Healthy overweight men and women (36 European Americans, 33 African Americans) were provided with food for 8 wk and received either a eucaloric standard diet (55% carbohydrate, 27% fat) or a eucaloric reduced-carbohydrate (RedCHO)/higher-fat diet (43% carbohydrate, 39% fat). Insulin sensitivity and β cell responsiveness were assessed at baseline and 8 wk by using a liquid meal tolerance test.

RESULTS

Insulin sensitivity did not change with diet (P = 0.1601). Static β cell response to glucose (ФS) was 28.5% lower after the RedCHO/higher-fat diet. Subgroup analyses indicated that lower ФS with the RedCHO/higher-fat diet occurred primarily among African Americans. A significant inverse association was observed for change in glucose area under the curve compared with change in ФS.

CONCLUSIONS

Consumption of a eucaloric 43% carbohydrate/39% fat diet for 8 wk resulted in down-regulation of β cell responsiveness, which was influenced by baseline phenotypic characteristics. Further study is needed to probe the potential cause-and-effect relation between change in ФS and change in glucose tolerance. This trial is registered at clinicaltrials.gov as NCT00726908.

Respiratory quotient predicts fat mass gain in premenopausal women

High respiratory quotient (RQ) has been associated with fat mass (FM) gain in some, but not all studies. Variability among results may reflect differences in the RQ variable measured (fasting vs. 24-h) or may be due to differences in control for factors that affect RQ, such as diet, energy balance, circulating insulin, and insulin sensitivity. The objective of this study was to determine whether different RQ values (fasting, sleeping, nonsleeping, and 24-h) would predict change in FM over 2 years in obesity-prone women, controlling for diet and adjusting for energy balance, circulating insulin, and insulin sensitivity. Participants were 33 previously overweight premenopausal women. Fasting, sleeping, nonsleeping, and 24-h RQ values were measured during controlled-diet conditions by respiratory chamber calorimetry. Intravenous glucose tolerance tests were also performed to adjust for fasting insulin, acute insulin response to glucose, and insulin sensitivity. Over the following 2 years, changes in FM were tracked annually by dual energy X-ray absorptiometry. High nonsleeping RQ (NSRQ) predicted 2-year change in FM independently of energy balance, circulating insulin, and insulin sensitivity. This observation suggests that low postprandial fat oxidation may uniquely predispose obesity-prone individuals to accrual of adipose tissue.

Serologic responses to eastern and western equine encephalomyelitis vaccination in previously vaccinated horses

A prospective study was performed to determine the serologic response of previously vaccinated horses to revaccination against eastern and western equine encephalomyelitis (EEE and WEE). Horses responded variably to each antigen, and some horses had low or undetectable antibodies 6 months after vaccination. Some horses did not develop increasing titers to EEE or WEE despite recent vaccination. Geometric mean titers peaked 2 weeks after revaccination and were significantly increased from before revaccination. Except for one horse, EEE:WEE titer ratios ranged from 0.25 to 2.0. Regular vaccination against EEE and WEE did not interfere with testing for Saint Louis encephalitis.

Gastrointestinal pathogenicity of adenoviruses and reoviruses isolated from broiler chickens in Alabama

Adenoviruses and reoviruses isolated from commercial broiler chickens were evaluated for gastrointestinal pathogenicity in specific-pathogen-free Leghorn chickens. The viruses were originally isolated from either the proventriculus or a gastrointestinal pool of tissues of broiler chickens with proventriculitis or enteritis. Isolates were cloned by terminal dilution. Day-old chickens were inoculated by oral and ocular routes with undiluted tissue culture fluids (titers of 10[2]-10[4] TCID50/ml) and then examined at necropsy on days 5, 10, and 15 postinoculation. Chickens in all virus groups (but not the control group) developed wet, unformed fecal droppings that persisted for the duration of the study. Mild lesions occurred in reovirus-inoculated chickens and included hyperplasia of lymphocyte aggregates in various organs and mild gizzard erosions. Chickens inoculated with adenovirus isolates developed marked gizzard erosions and necrotizing pancreatitis as well as mild proventriculitis. Intranuclear viral inclusion bodies occurred in gizzard epithelium and pancreatic acinar cells at the sites of lesions. Lymphocytic atrophy occurred in the bursa of Fabricius. Respective viruses were reisolated from proventriculus and duodenum collected from chickens of each group; no viruses were isolated from controls. Under the conditions of this study, adenovirus isolates were more pathogenic than the reovirus isolates in the digestive system.

Immunohistochemical detection of Newcastle disease virus in chickens

An immunoperoxidase histochemical technique utilizing a monoclonal primary antibody was developed for detection of Newcastle disease virus (NDV) antigen in tissues from chickens. The technique was applied to trachea, lung, spleen, Harderian gland, and cecal tonsil harvested from specific-pathogen-free (SPF) chickens at 2, 5, 7, 10, and 14 days postinoculation (PI) with NDV, and to corresponding tissues from commercial broiler chickens representing 30 cases of spontaneous respiratory disease. Positive staining occurred in the cytoplasm of respiratory epithelial cells in the trachea or bronchi of NDV-inoculated SPF chickens at 5 and 7 days PI. Staining also occurred in the respiratory epithelium of the trachea and bronchi of commercial broilers from seven of 30 cases of spontaneous respiratory disease. These results indicate that the immunoperoxidase technique has value as a rapid diagnostic test for Newcastle disease.