Tolerability and Acceptability of an Exogenous Ketone Monoester and Ketone Monoester/Salt Formulation in Humans

Exogenous ketone ester and ketone ester mixed with ketone free acid formulations are rapidly entering the commercial marketspace. Short-term animal and human studies using these products suggest significant potential for primary or secondary prevention of a number of chronic disease conditions. However, a number of questions need to be addressed by the field for optimal use in humans, including variable responses among available exogenous ketones at different dosages; frequency of dosing; and their tolerability, acceptability, and efficacy in long-term clinical trials. The purpose of the current investigation was to examine the tolerability, acceptability, and circulating R-beta-hydroxybutyrate (R-βHB) and glucose responses to a ketone monoester (KME) and ketone monoester/salt (KMES) combination at 5 g and 10 g total R-βHB compared with placebo control (PC). Fourteen healthy young adults (age: 21 ± 2 years, weight: 69.7 ± 14.2 kg, percent fat: 28.1 ± 9.3%) completed each of the five study conditions: placebo control (PC), 5 g KME (KME5), 10 g KME (KME10), 5 g (KMES5), and 10 g KMES (KMES10) in a randomized crossover fashion. Circulating concentrations of R-βHB were measured at baseline (time 0) following an 8-12 h overnight fast and again at 15, 30, 60, and 120 min following drink ingestion. Participants also reported acceptability and tolerability during each condition. Concentrations of R-βHB rose to 2.4 ± 0.1 mM for KME10 after 15 min, whereas KMES10 similarly peaked (2.1 ± 0.1 mM) but at 30 min. KME5 and KMES5 achieved similar peak R-βHB concentrations (1.2 ± 0.7 vs. 1.1 ± 0.5 mM) at 15 min. Circulating R-βHB concentrations were similar to baseline for each condition by 120 min. Negative correlations were observed between R-βHB and glucose at the 30 min time point for each condition except KME10 and PC. Tolerability was similar among KME and KMES, although decreases in appetite were more frequently reported for KMES. Acceptability was slightly higher for KMES due to the more frequently reported aftertaste for KME. The results of this pilot investigation illustrate that the KME and KMES products used increase circulating R-βHB concentrations to a similar extent and time course in a dose-dependent fashion with slight differences in tolerability and acceptability. Future studies are needed to examine variable doses, frequency, and timing of exogenous ketone administration for individuals seeking to consume ketone products for health- or sport performance-related purposes.

Perspective: Acknowledging a Hierarchy of Social Needs in Diabetes Clinical Care and Prevention

The evidence of suboptimal social determinants of health (SDoH) on poor health outcomes has resulted in widespread calls for research to identify ways to measure and address social needs to improve health outcomes and reduce disparities. While assessing SDoH has become increasingly important in diabetes care and prevention research, little guidance has been offered on how to address suboptimal determinants in diabetes-related clinical care, prevention efforts, medical education and research. Not surprisingly, many patients experience multiple social needs - some that are more urgent (housing) than others (transportation/resources), therefore the order in which these needs are addressed needs to be considered in the context of diabetes care/outcomes. Here we discuss how conceptualizing diabetes related health through the lens of Maslow's hierarchy of needs has potential to help prioritize individual social needs that should be addressed to improve outcomes in the context of population-level determinants in the communities where people live.

Using the TIDieR checklist to describe development and integration of a web-based intervention promoting healthy eating and regular exercise among older cancer survivors

Objective

To facilitate replication and future intervention design of web-based multibehavior lifestyle interventions, we describe the rationale, development, and content of the AiM, Plan, and act on LIFestYles (AMPLIFY) Survivor Health intervention which provides healthy eating and exercise behavior change support for older cancer survivors. The intervention promotes weight loss, improvements in diet quality, and meeting exercise recommendations.

Methods

The Template for Intervention Description and Replication (TIDieR) checklist was used to provide a comprehensive description of the AMPLIFY intervention, consistent with CONSORT recommendations.

Results

A social cognitive theory web-based intervention founded on the core components of efficacious print and in-person interventions was conceptualized and developed through an iterative collaboration involving cancer survivors, web design experts, and a multidisciplinary investigative team. The intervention includes the AMPLIFY website, text and/or email messaging, and a private Facebook group. The website consists of: (1) Sessions (weekly interactive e-learning tutorials); (2) My Progress (logging current behavior, receiving feedback, setting goals); (3) Tools (additional information and resources); (4) Support (social support resources, frequently asked questions); and (5) Home page. Algorithms were used to generate fresh content daily and weekly, tailor information, and personalize goal recommendations. An a priori rubric was used to facilitate intervention delivery as healthy eating only (24 weeks), exercise only (24 weeks), or both behaviors concurrently over 48 weeks.

Conclusions

Our TIDieR-guided AMPLIFY description provides pragmatic information helpful for researchers designing multibehavior web-based interventions and enhances potential opportunities to improve such interventions.

The Changing Landscape of Nutrition in Cystic Fibrosis: The Emergence of Overweight and Obesity

Cystic fibrosis has historically been characterized by malnutrition, and nutrition strategies have placed emphasis on weight gain due to its association with better pulmonary outcomes. As treatment for this disease has significantly improved, longevity has increased and overweight and obesity have emerged issues in this population. The effect of excess weight and adiposity on CF clinical outcomes is unknown but may produce similar health consequences and obesity-related diseases as those observed in the general population. This review examines the prevalence of overweight and obesity in CF, the medical and psychological impact, as well as the existing evidence for treatment in the general population and how this may be applied to people with CF. Clinicians should partner with individuals with CF and their families to provide a personalized, interdisciplinary approach that includes dietary modification, physical activity, and behavioral intervention. Additional research is needed to identify the optimal strategies for preventing and addressing overweight and obesity in CF.

Ketogenic Diet for Cancer: Critical Assessment and Research Recommendations

Despite remarkable improvements in screening, diagnosis, and targeted therapies, cancer remains the second leading cause of death in the United States. It is increasingly clear that diet and lifestyle practices play a substantial role in cancer development and progression. As such, various dietary compositions have been proposed for reducing cancer risk and as potential adjuvant therapies. In this article, we critically assess the preclinical and human trials on the effects of the ketogenic diet (KD, i.e., high-fat, moderate-to-low protein, and very-low carbohydrate content) for cancer-related outcomes. The mechanisms underlying the hypothesized effects of KD, most notably the Warburg Effect, suggest that restricting carbohydrate content may impede cancer development and progression via several pathways (e.g., tumor metabolism, gene expression). Overall, although preclinical studies suggest that KD has antitumor effects, prolongs survival, and prevents cancer development, human clinical trials are equivocal. Because of the lack of high-quality clinical trials, the effects of KD on cancer and as an adjunctive therapy are essentially unknown. We propose a set of research recommendations for clinical studies examining the effects of KD on cancer development and progression.

An Exploratory Analysis of the Association Between Catechol-O-Methyltransferase and Response to a Randomized Open-Label Placebo Treatment for Cancer-Related Fatigue

Previous studies have identified catechol-O-methyltransferase (COMT), as a key enzyme influencing sympathetic function. Although the COMT SNP rs4680 and rs4818, are well-studied, little is known about their influence on cancer-related fatigue (CrF) and placebo response. In this study, we examined whether genetic variation in COMT, at the functional SNP rs4680 and linked rs4818, influenced open-label placebo (OLP) responses found in cancer survivors reporting moderate to severe CrF. We randomized cancer survivors (N = 74) reporting moderate-to-severe CrF to receive OLP or to treatment-as-usual (TAU) and assessed if rs4680 and rs4818 were associated with changes in fatigue severity and fatigue-distressed quality of life. At the end of the initial 21 days, the treatments were crossed over and both groups were re-assessed. Participants with the rs4680 high-activity G-allele (G/G or G/A) or rs4818 C/G genotypes reported significant decreases in fatigue severity and improvements in fatigue-distressed quality of life. The COMT rs4818 findings replicated findings in a similar study of OLP in cancer fatigue. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT02522988.

A Pilot Study of Associations Between Visceral Fat, IL-6, and Urinary F2-Isoprostanes in Older Adults Exposed to a Diet Intervention

BACKGROUND

Short-term markers of successful visceral adipose tissue (VAT) loss are needed. Urinary F2-isoprostanes might serve as a marker for intensified lipid metabolism, whereas circulating IL-6 might stimulate fat oxidation and enhance mobilization of VAT.

OBJECTIVES

This pilot study was designed to explore the hypotheses that 1) reduction in VAT is associated with increase in IL-6, and 2) that increases in urinary F2-isoprostanes are associated with increases in IL-6 and reduction in VAT.

METHODS

Eighteen participants (aged 60-75 y, BMI 30-40 kg/m2) were randomly assigned to either a very-low-carbohydrate diet (VLCD; <10:25:>65% energy from carbohydrate:protein:fat) or a low-fat diet (LFD; 55:25:20%) for 8 wk. Changes in fat distribution were assessed by MRI. Four urinary F2-isoprostane isomers were quantified in 24-h urine collection using LC-MS/MS analyses. Changes in 4 F2-isoprostane isomers were summarized using factor analysis (Δ-F2-isoprostane factor). Statistical significance was set at P < 0.1.

RESULTS

Within the VLCD group, change in VAT was inversely associated with change in IL-6 (r = -0.778, P = 0.069) and Δ-F2-isoprostane factor (r = -0.690, P = 0.086), demonstrating that participants who maintained higher concentrations of F2-isoprostane factor across the intervention showed greater decreases in VAT. A positive relation between Δ-F2-isoprostane factor and change in IL-6 was observed (r = 0.642, P = 0.062). In the LFD group, no significant associations between changes in VAT, F2-isoprostane factor, or IL-6 were observed.

CONCLUSIONS

Results from this exploratory study in older adults with obesity suggest that, in the context of a VLCD, IL-6 could be involved in VAT mobilization, and urinary F2-isoprostanes could reflect intensified oxidation of mobilized fatty acids.Trial registration: This study is registered at clinicaltrials.gov as NCT02760641.

Optimism, perceived control over stress, and coping

To examine the ability of the expectancy‐based personality dimensions dispositional optimism and perceived control over stress to predict the ways in which people characteristically attempt to cope with stress, 420 undergraduate students completed the Life Orientation Test (LOT; Scheier and Carver, 1985), a measure of perceived control over stress, and the dispositional version of the COPE Inventory (Carver, Scheier and Weintraub, 1989). The results revealed a modest but reliable positive correlation between optimism and the perceived control measure. Principal‐components analysis of the COPE revealed a factor structure which was generally in accord with prior research. Optimism was positively correlated with active coping and positive reinterpretation, and negatively correlated with focusing on and venting of emotion. Perceived control over stress was negatively correlated with behavioural disengagement. Implications and directions for future research are discussed.

Effects of weight loss during a very low carbohydrate diet on specific adipose tissue depots and insulin sensitivity in older adults with obesity: a randomized clinical trial

Background

Insulin resistance and accumulation of visceral adipose tissue (VAT) and intermuscular adipose tissue (IMAT) place aging adults with obesity at high risk of cardio-metabolic disease. A very low carbohydrate diet (VLCD) may be a means of promoting fat loss from the visceral cavity and skeletal muscle, without compromising lean mass, and improve insulin sensitivity in aging adults with obesity.

Objective

To determine if a VLCD promotes a greater loss of fat (total, visceral and intermuscular), preserves lean mass, and improves insulin sensitivity compared to a standard CHO-based/low-fat diet (LFD) in older adults with obesity.

Design

Thirty-four men and women aged 60–75 years with obesity (body mass index [BMI] 30-40 kg/m²) were randomized to a diet prescription of either a VLCD (< 10:25:> 65% energy from CHO:protein:fat) or LFD diet (55:25:20) for 8 weeks. Body composition by dual-energy X-ray absorptiometry (DXA), fat distribution by magnetic resonance imaging (MRI), insulin sensitivity by euglycemic hyperinsulinemic clamp, and lipids by a fasting blood draw were assessed at baseline and after the intervention.

Results

Participants lost an average of 9.7 and 2.0% in total fat following the VLCD and LFD, respectively (p < 0.01). The VLCD group experienced ~ 3-fold greater loss in VAT compared to the LFD group (− 22.8% vs − 1.0%, p < 0.001) and a greater decrease in thigh-IMAT (− 24.4% vs − 1.0%, p < 0.01). The VLCD group also had significantly greater thigh skeletal muscle (SM) at 8 weeks following adjustment for change in total fat mass. Finally, the VLCD had greater increases in insulin sensitivity and HDL-C and decreases in fasting insulin and triglycerides compared to the LFD group.

Conclusions

Weight loss resulting from consumption of a diet lower in CHO and higher in fat may be beneficial for older adults with obesity by depleting adipose tissue depots most strongly implicated in poor metabolic and functional outcomes and by improving insulin sensitivity and the lipid profile.

Trial registration

NCT02760641. Registered 03 May 2016 - Retrospectively registered.

Does Adherence to Mediterranean Diet Mediate the Association Between Food Environment and Obesity Among Non-Hispanic Black and White Older US Adults? A Path Analysis

PURPOSE

This study aims to test the hypothesis that in addition to a direct effect of food environment on obesity, food environment is indirectly associated with obesity through consuming Mediterranean diet (MD).

DESIGN

Cross-sectional secondary data analysis.

SETTING

Nationwide community-dwelling residency.

SAMPLE

A total of 20 897 non-Hispanic black and white adults aged ≥45 years who participated in the REasons for Geographic and Racial Differences in Stroke study and completed baseline assessment during January 2003 and October 2007.

MEASURES

The Modified Retail Food Environment Index (mRFEI; 0-100) was used as food environment indicator. The MD score (0-9) was calculated to indicate the dietary pattern adherence. Body mass index (BMI; kg/m²) was used to estimate obesity.

ANALYSIS

Path analysis was used to quantify the pathways between food environment, MD adherence, and obesity. Proper data transformation was made using Box-Cox power transformation to meet certain analysis assumptions.

RESULTS

The participants were from 49 states of the United States, with the majority (64.42%) residing in the South. Most of the participants were retired, female, white, married, having less than college graduate education, having annual household income ≤75 000, and having health insurance. The means of mRFEI was 10.92 (standard deviation [SD] = 10.19), MD score was 4.36 (SD = 1.70), and the BMI was 28.96 kg/m² (SD = 5.90). Access to healthy food outlets (β = .04, P < .0001) and MD adherence (β = .08, P < .0001) had significant and inverse relationships with BMI, respectively. Mediterranean diet adherence mediated the relationship between food environment and obesity among a subpopulation who had an annual household income of <$75 000 (β = -.02, P = .0391).

CONCLUSION

Population-tailored interventions/policies to modify food environment and promote MD consumption are needed in order to combat the obesity crisis in the United States.

Childhood obesity intervention studies: A narrative review and guide for investigators, authors, editors, reviewers, journalists, and readers to guard against exaggerated effectiveness claims

Being able to draw accurate conclusions from childhood obesity trials is important to make advances in reversing the obesity epidemic. However, obesity research sometimes is not conducted or reported to appropriate scientific standards. To constructively draw attention to this issue, we present 10 errors that are commonly committed, illustrate each error with examples from the childhood obesity literature, and follow with suggestions on how to avoid these errors. These errors are as follows: using self-reported outcomes and teaching to the test; foregoing control groups and risking regression to the mean creating differences over time; changing the goal posts; ignoring clustering in studies that randomize groups of children; following the forking paths, subsetting, p-hacking, and data dredging; basing conclusions on tests for significant differences from baseline; equating "no statistically significant difference" with "equally effective"; ignoring intervention study results in favor of observational analyses; using one-sided testing for statistical significance; and stating that effects are clinically significant even though they are not statistically significant. We hope that compiling these errors in one article will serve as the beginning of a checklist to support fidelity in conducting, analyzing, and reporting childhood obesity research.

A Ketogenic Diet Is Acceptable in Women with Ovarian and Endometrial Cancer and Has No Adverse Effects on Blood Lipids: A Randomized, Controlled Trial

Ketogenic diets (KDs) are emerging as effective therapies for several chronic diseases, including cancer. However, concerns regarding safety and adherence may prevent clinicians from prescribing KDs. We hypothesized that a KD does not negatively affect blood lipid profile compared to a lower-fat diet in ovarian and endometrial cancer patients, and that KD subjects would demonstrate acceptable adherence. Subjects were randomized to either a KD (70% fat, 25% protein, 5% carbohydrate), or the American Cancer Society diet (ACS; high-fiber and lower-fat). Blood lipids and ketones were measured at baseline and after 12 weeks of the assigned intervention. Adherence measures included urinary ketones in the KD and 4 days' diet records. Diet records were also examined to identify general patterns of consumption. Differences between the diets on blood lipids and dietary intake were assessed with Analysis of covariance and independent t-tests. Correlation analyses were used to estimate associations between dietary intake and serum analytes. At 12 weeks, there were no significant differences between diet groups in blood lipids, after adjusting for baseline values and weight loss. Adherence among KD subjects ranged from 57% to 80%. These findings suggest that KDs may be a safe and achievable component of treatment for some cancer patients.

Slow speed resistance exercise training in children with polyarticular juvenile idiopathic arthritis

Background: Juvenile idiopathic arthritis (JIA) is an inflammatory autoimmune disease that can cause severe impairment and disability. Exercise is recommended to preserve joint mobility and function. Our objectives were to assess the safety, feasibility, and effects of slow speed resistance exercise in children with polyarticular JIA. Methods: Patients were recruited from a pediatric rheumatology clinic at an urban hospital and randomized to exercise or control groups. In the intervention group, slow speed resistance exercise with individualized instruction by a certified trainer was performed 1-2 times per week for 12 weeks. The control group performed home-based aerobic exercise 3 days per week for 12 weeks. Pre and post-body composition measurements by dual-energy X-ray absorptiometry; aerobic fitness by peak oxygen uptake during cycle ergometry; isometric muscle strength; and quality of life measures were obtained. Results: In the exercise group, 9/17 (53%) completed any exercise training. Of these nine subjects, five (55%) completed all 12 weeks of the protocol. In the control group, 8/16 (50%) reported compliance with the recommended aerobic exercise training at least one time per week. Only 2 subjects (12%) reported exercising more than once per week. There was no significant difference between pre- and post-measurements in any category in the exercise group. There was also significantly elevated body fat in both groups with only 17% in the control group and 23% in the exercise group meeting recommended <30% total body fat levels. Conclusions: Children with JIA participated safely in this resistance exercise protocol. The exercise was well-tolerated with no serious adverse events noted. While individual subjects reported improvement in fatigue and improved energy, there was no statistical difference in pre- and post-exercise measures of body composition or quality of life. Identifying ways to improve adherence and encourage exercise in children with JIA is important.

Dietary R, S-1,3-butanediol diacetoacetate reduces body weight and adiposity in obese mice fed a high-fat diet

The dietary R-3-hydroxybutyrate- R-1,3-butanediol monoester increases resting energy expenditure (REE) and markers of brown and white adipose thermogenesis in lean mice. The purpose of this investigation was to determine whether the ketone ester, R, S-1,3-butanediol diacetoacetate (BD-AcAc2), increases energy expenditure and markers of adipose tissue thermogenesis in the context of high-fat diet (HFD)-induced obesity. Thirty-five-week-old male C57BL/6J mice were placed on an ad libitum HFD (45% kcal) for 10 wk. The mice were then randomized to 1 of 3 groups ( n = 10 per group) for an additional 12 wk: 1) control (Con), continuous HFD, 2) pair-fed (PF) to ketone ester (KE); and 3) KE: HFD+30% energy from BD-AcAc2. Mean energy intake throughout the study was ∼26% lower in the KE compared to the Con group (8.2 ± 0.5 vs. 11.2 ± 0.7 kcal/d; P < 0.05). Final body weight (26.8 ± 3.6 vs. 34.9 ± 4.8 g; P < 0.001) and fat mass (5.2 ± 1.2 vs. 11.3 ± 4.5 g; P < 0.001) of the KE group was significantly lower than PF, despite being matched for energy provisions. Differences in body weight and adiposity were accompanied by higher REE and total energy expenditure in the KE group compared to PF after adjustment for lean body mass and fat-mass ( P = 0.001 and 0.007, respectively). Coupled or uncoupled mitochondrial respiratory rates in skeletal muscle were not different among groups, but markers of mitochondrial uncoupling and thermogenesis (uncoupling protein-1, deiodinase-2, and peroxisome proliferator-activated receptor γ coactivator-1α) were higher in interscapular brown adipose tissue (BAT) of mice receiving the KE diet. The absence of mitochondrial uncoupling in skeletal muscle and increased markers of mitochondrial uncoupling in BAT suggest that BD-AcAc2 initiates a transcriptional signature consistent with BAT thermogenesis in the context of HFD-induced obesity.-Davis, R. A. H., Deemer, S. E., Bergeron, J. M., Little, J. T., Warren, J. L., Fisher, G., Smith, D. L., Jr., Fontaine, K. R., Dickinson, S. L., Allison, D. B., Plaisance, E. P. Dietary R, S-1,3-butanediol diacetoacetate reduces body weight and adiposity in obese mice fed a high-fat diet.

Association of community food environment and obesity among US adults: a geographical information system analysis

Background

Emerging studies have investigated the contribution of food environment to obesity in the USA. However, the findings were inconsistent. Methodological explanations for the inconsistent findings included: (1) using individual store/restaurant exposure as food environment indicator, and (2) not accounting for non-stationarity assumption. This study aimed to describe the spatial distribution of obesity and examine the association between community food environment and obesity, and the variation of magnitude and direction of this association across the USA.

Methods

Data from 20 897 adults who participated in the REasons for Geographic and Racial Differences in Stroke study and completed baseline assessment between January 2003 and October 2007 were eligible in analysis. Hot Spot analysis was used to assess the spatial distribution of obesity. The association between community food environment and obesity and the variation of this association across the USA were examined using global ordinary least squares regression and local geographically weighted regression.

Results

Higher body mass index (BMI) clusters were more likely to locate in socioeconomically disadvantaged, rural, minority neighbourhoods with a smaller population size, while lower BMI clusters were more likely to appear in more affluent, urban neighbourhoods with a higher percentage of non-Hispanic white residences. There was an overall significant, inverse association between community food environment and obesity (β=−0.0210; p<0.0001). Moreover, the magnitude and direction of this association varied significantly across the US regions.

Conclusions

The findings underscored the need for geographically tailored public health interventions and policies to address unique local food environment issues to achieve maximum effects on obesity prevention.

Two-Year Follow-Up of Impaired Range of Motion in Chronic Fatigue Syndrome

OBJECTIVE

To measure changes in range of motion (ROM) over time in a cohort of 55 adolescents and young adults with chronic fatigue syndrome and to determine whether changes in ROM correlated with changes in health-related quality of life.

STUDY DESIGN

Participants underwent a standardized examination of 11 areas of limb and spine ROM at baseline and at 3- to 6-month intervals for 2 years, resulting in a ROM score that ranged from 0 (normal throughout) to 11 (abnormal ROM in all areas tested). We measured the time until the ROM score was ≤2 (the score in healthy age-matched controls). Change in ROM was measured by subtracting the 24-month from the baseline ROM score and by summing the degrees of change in the 10 tests with continuous outcomes. Health-related quality of life was measured using the Pediatric Quality of Life Inventory 4.0 (PedsQL).

RESULTS

The mean age at enrollment was 16.5 years (range 10-23). Two-year follow-up was available for 53 (96%). The proportion with a ROM score of >2 fell gradually over 2 years, from 78% at entry to 20% at 24 months (P < .001). ROM scores improved from a median of 5 at entry to 2 at 24 months (P < .001). The change in the summed degrees of improvement in ROM correlated positively with improvement in the PedsQL physical function subscale (r = 0.30; P < .03).

CONCLUSIONS

In association with multimodal therapy, young people with chronic fatigue syndrome experienced progressively less impairment in ROM over 2 years, correlating with improvements in the physical function subscale of the PedsQL.

A Ketogenic Diet Reduces Central Obesity and Serum Insulin in Women with Ovarian or Endometrial Cancer

Background

The glycolytic nature of cancer cells presents a potential treatment target that may be addressed by a ketogenic diet (KD).

Objective

We hypothesized that a KD would improve body composition and lower serum insulin and insulin-like growth factor-I (IGF-I) in women with ovarian or endometrial cancer.

Methods

In this randomized controlled trial, women with ovarian or endometrial cancer [age: ≥19 y; body mass index (kg/m2): ≥18.5] were randomly assigned to a KD (70:25:5 energy from fat, protein, and carbohydrate) or the American Cancer Society diet (ACS; high-fiber, low-fat). Body composition (DXA) and fasting serum insulin, IGF-I, and β-hydroxybutyrate were obtained at baseline and at 12 wk; urinary ketones were also measured throughout the intervention. We assessed differences between the diets with ANCOVA and independent t tests. We used correlation analyses to estimate associations between changes in serum analytes and body composition.

Results

After 12 wk, the KD (compared with ACS) group had lower adjusted total (35.3 compared with 38.0 kg, P < 0.05) and android (3.0 compared with 3.3 kg, P < 0.05) fat mass. Percentage of change in visceral fat was greater in the KD group (compared with the ACS group; -21.2% compared with -4.6%, P < 0.05). Adjusted total lean mass did not differ between the groups. The KD (compared with ACS) group had lower adjusted fasting serum insulin (7.6 compared with 11.2 µU/mL, P < 0.01). There was a significant inverse association between the changes in serum β-hydroxybutyrate and IGF-I concentrations (r = -0.57; P < 0.0001).

Conclusions

In women with ovarian or endometrial cancer, a KD results in selective loss of fat mass and retention of lean mass. Visceral fat mass and fasting serum insulin also are reduced by the KD, perhaps owing to enhanced insulin sensitivity. Elevated serum β-hydroxybutyrate may reflect a metabolic environment inhospitable to cancer proliferation. This trial was registered at www.clinicaltrials.gov as NCT03171506.

Body Composition and Mortality in Mexican American Adults: Results from the National Health and Nutrition Examination Survey

OBJECTIVE

Epidemiologic analyses indicate a lack of association between BMI (kg/m² ) and mortality among Hispanic adults. Because BMI provides only a surrogate for the real variable of interest, adiposity, this study evaluated associations between measures of body composition and mortality.

METHODS

Using data from US-residing Mexican Americans in the National Health and Nutrition Examination Survey (NHANES) III (n = 4,480) and NHANES 1999-2010 (n = 5,849), the association between seven measures of body composition measured via anthropometry and bio-electrical impedance analysis (i.e., waist circumference, waist-to-height ratios [WHtR], skinfolds, lean mass, fat mass, percent body fat, and BMI) and all-cause and cardiovascular and diabetes mortality were examined. Additional analyses were stratified by gender.

RESULTS

Waist circumference (hazard ratio [HR]: 1.04, 95% CI: 1.01-1.07) and WHtR (HR: 1.08, 95% CI: 1.03-1.14) were weakly associated with an increased all-cause mortality, while WHtR was associated with an increased risk of diabetes-related death (HR: 1.26, 95% CI: 1.07-1.49). In gender-stratified analyses, there was an increased risk of mortality in females who had increases in WHtR and waist circumference for all-cause mortality and cardiovascular deaths.

CONCLUSIONS

Waist circumference and WHtR were associated with increased risk of all-cause and diabetes-related mortality in US-residing Mexican American adults.

Higher carbohydrate intake is associated with increased risk of all-cause and disease-specific mortality in head and neck cancer patients: results from a prospective cohort study

No studies have evaluated associations between carbohydrate intake and head and neck squamous cell carcinoma (HNSCC) prognosis. We prospectively examined associations between pre- and post-treatment carbohydrate intake and recurrence, all-cause mortality, and HNSCC-specific mortality in a cohort of 414 newly diagnosed HNSCC patients. All participants completed pre- and post-treatment Food Frequency Questionnaires (FFQs) and epidemiologic surveys. Recurrence and mortality events were collected annually. Multivariable Cox Proportional Hazards models tested associations between carbohydrate intake (categorized into low, medium and high intake) and time to recurrence and mortality, adjusting for relevant covariates. During the study period, there were 70 deaths and 72 recurrences. In pretreatment analyses, high intakes of total carbohydrate (HR: 2.29; 95% CI: 1.23-4.25), total sugar (HR: 3.03; 95% CI: 1.12-3.68), glycemic load (HR: 2.10; 95% CI: 1.15-3.83) and simple carbohydrates (HR 2.26; 95% CI 1.19-4.32) were associated with significantly increased risk of all-cause mortality compared to low intake. High intakes of carbohydrate (HR 2.45; 95% CI: 1.23-4.25) and total sugar (HR 3.03; 95% CI 1.12-3.68) were associated with increased risk of HNSCC-specific mortality. In post-treatment analyses, medium fat intake was significantly associated with reduced risk of recurrence (HR 0.08; 95% CI 0.01-0.69) and all-cause mortality (HR 0.27; 95% CI 0.07-0.96). Stratification by tumor site and cancer stage in pretreatment analyses suggested effect modification by these factors. Our data suggest high pretreatment carbohydrate intake may be associated with adverse prognosis in HNSCC patients. Clinical intervention trials to further examine this hypothesis are warranted.

Open-Label Placebo Treatment for Cancer-Related Fatigue: A Randomized-Controlled Clinical Trial

The purpose of this 21-day assessor blinded, randomized-controlled trial was to compare an open-label placebo (OLP) to treatment as usual (TAU) for cancer survivors with fatigue. This was followed by an exploratory 21-day study in which TAU participants received OLPs while OLP participants in the main study were followed after discontinuing placebos. Cancer survivors (N = 74) who completed cancer treatment 6 months to 10 years prior to enrollment reporting at least moderate fatigue (i.e., ≥4 on a 0-10 scale) were randomized to OLP or TAU. Those randomized to OLP took 2 placebo pills twice a day for 21 days. Compared to those randomized to TAU, OLP participants reported a 29% improvement in fatigue severity (average difference in the mean change scores (MD) 12.47, 95% CI 3.32, 21.61; P = 0.008), medium effect (d = 0.63), and a 39% improvement in fatigue-disrupted quality of life (MD = 11.76, 95% CI 4.65, 18.86; P = 0.002), a large effect (d = 0.76). TAU participants who elected to try OLP for 21-days after the main study reported reductions in fatigue of a similar magnitude for fatigue severity and fatigue-disrupted quality of life (23% and 35%, respectively). OLP may reduce fatigue symptom severity and fatigue-related quality of life disruption in cancer survivors.

Body Mass Index and Subjective Social Status: The Coronary Artery Risk Development in Young Adults Study

OBJECTIVE

Subjective social status (SSS), or perceived social status, may explain, in part, the relationship between socioeconomic status (SES) and obesity. The objective of this study was to test whether SSS mediates the relationship between two indicators of SES (income and education) and body mass index (BMI).

METHODS

A cross-sectional, structural equation path analysis was applied to the Coronary Artery Risk Development in Young Adults (CARDIA) study (n = 2,624). The analysis tested whether SSS (MacArthur scale), education, and income were associated with BMI at the year 20 examination (adjusting for sex, age, and race), and it was hypothesized that the associations of education and income with BMI would be at least partly mediated by SSS.

RESULTS

SSS had a significant direct effect on BMI (-0.21, P = 0.018). Education had a significant direct relationship with SSS (0.11, P < 0.001) and a small but significant indirect relationship with BMI through SSS (-0.02, P = 0.022). Although income did not have a significant direct relationship with BMI, it did have a significant indirect relationship through SSS (b = -0.05, P = 0.019).

CONCLUSIONS

Results are consistent with the hypothesized model in which SSS partially mediates the relationship between SES indicators and BMI.

The development of scientific evidence for health policies for obesity: why and how?

Potential obesity-related policy approaches have recently been receiving more attention. Although some have been implemented and others only proposed, few have been formally evaluated. We discuss the relevance, and in some cases irrelevance, of some of the types of evidence that are often brought to bear in considering obesity-related policy decisions. We discuss major methods used to generate such evidence, emphasizing study design and the varying quality of the evidence obtained. Third, we consider what the standards of evidence should be in various contexts, who ought to set those standards, as well as the inherent subjectivity involved in making policy decisions. Finally, we suggest greater transparency from both academics and policymakers in the acknowledgment of subjectivities so they can distinguish and communicate the roles of empirical evidence and subjective values in the formulation of policy.

Randomization to randomization probability: Estimating treatment effects under actual conditions of use

Blinded randomized controlled trials (RCT) require participants to be uncertain if they are receiving a treatment or placebo. Although uncertainty is ideal for isolating the treatment effect from all other potential effects, it is poorly suited for estimating the treatment effect under actual conditions of intended use-when individuals are certain that they are receiving a treatment. We propose an experimental design, randomization to randomization probabilities (R2R), which significantly improves estimates of treatment effects under actual conditions of use by manipulating participant expectations about receiving treatment. In the R2R design, participants are first randomized to a value, π, denoting their probability of receiving treatment (vs. placebo). Subjects are then told their value of π and randomized to either treatment or placebo with probabilities π and 1-π, respectively. Analysis of the treatment effect includes statistical controls for π (necessary for causal inference) and typically a π-by-treatment interaction. Random assignment of subjects to π and disclosure of its value to subjects manipulates subject expectations about receiving the treatment without deception. This method offers a better treatment effect estimate under actual conditions of use than does a conventional RCT. Design properties, guidelines for power analyses, and limitations of the approach are discussed. We illustrate the design by implementing an RCT of caffeine effects on mood and vigilance and show that some of the actual effects of caffeine differ by the expectation that one is receiving the active drug. (PsycINFO Database Record

Placebo effects in obesity research

Research participants randomized to placebo-control conditions often report improved outcomes and can manifest physiologic responses that mirror those of participants who received the bioactive compound. Recent studies show that placebos can have beneficial effects even when the individual is aware that he/she is receiving a placebo, suggesting that the therapeutic context in which a placebo is delivered can be powerful. This context includes environmental and psychosocial factors, such as information disclosure, expectations, conditioning and empathy, embedded within research and clinical encounters that may influence outcomes. In this article, we review these placebo-related factors (PRFs), consider how they may influence the results typically attributed to diet and lifestyle interventions, and offer suggestions on enhancing PRFs in clinical obesity settings.

Hope thinking and past trauma mediate the relationships of body mass index with perceived mental health treatment need and mental health treatment use

Greater body mass is associated with a greater risk of mental health conditions and more frequent mental health treatment use. However, factors that might influence perceived mental health treatment need and mental health treatment use among those of greater weight, including hope thinking, trauma history and perceived mental health treatment stigma, are not well understood.

OBJECTIVE

The objective of this study was to determine if hope thinking, trauma history and/or perceived mental health treatment stigma mediate the relationships of body mass index [BMI] with perceived mental health treatment need and mental health treatment use.

METHOD

Primary care clinic patients in the Midwest United States (N = 196; BMI range = 18.5 to 47.0, mean = 29.26 ± 6.61, median = 27.90) were recruited to complete a battery of self-report measures that assessed perceived mental health treatment need, mental health treatment use, hope thinking (Trait Hope Scale), trauma history (a single-item traumatic event history screen from the posttraumatic stress disorder module of the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition), and perceived mental health treatment stigma (Stigma Scale for Receiving Psychological Help).

RESULTS

Reduced hope thinking and a greater incidence of past trauma accounted for greater perceived mental health treatment need and greater mental health treatment use among those of greater BMI. BMI was not related to perceived unmet mental health treatment need.

CONCLUSION

Increased perceived mental health treatment need and mental health treatment use among those of greater BMI may be explained by lower hope thinking and a greater incidence of trauma in this population. Heavier patients may benefit from interventions designed to augment hope and address traumatic histories.

Randomized controlled trial examining expectancy effects on the accuracy of weight measurement

BACKGROUND

Researchers and participants' expectations can influence treatment response. Less is known about the effects of researchers' expectations on the accuracy of data collection in the context of a weight loss trial.

METHODS

Student raters (N = 58; age = 20.1 ± 2.3 years) were recruited to weigh individuals who they thought were completing a 12-month weight loss trial, although these 'participants' were actually standardized patients (SPs) playing these roles. Prior to data collection, student raters were provided information suggesting that the tested treatment had been effective. Each student rater received a list of 9-10 'participants' to weigh. While the list identified each person as 'treatment' or 'control', this assignment was at random, which allowed us to examine the effects of non-blinding and expectancy manipulation on weight measurement accuracy. We hypothesized that raters would record the weights of 'treatment participants' as lower than those of 'control participants'.

RESULTS

Contrary to our hypothesis, raters recorded weights that were 0.293 kg heavier when weighing 'treatment' vs. 'control' SPs, although this difference was not significant (P = 0.175).

CONCLUSIONS

This pilot study found no evidence that manipulating expectancies about treatment efficacy or not blinding raters biased measurements. Future work should examine other biases which may be created by not blinding research staff who implement weight loss trials as well as the participants in those trials.

Packet randomized experiments for eliminating classes of confounders

BACKGROUND

Although randomization is considered essential for causal inference, it is often not possible to randomize in nutrition and obesity research. To address this, we develop a framework for an experimental design-packet randomized experiments (PREs), which improves causal inferences when randomization on a single treatment variable is not possible. This situation arises when subjects are randomly assigned to a condition (such as a new roommate) which varies in one characteristic of interest (such as weight), but also varies across many others. There has been no general discussion of this experimental design, including its strengths, limitations, and statistical properties. As such, researchers are left to develop and apply PREs on an ad hoc basis, limiting its potential to improve causal inferences among nutrition and obesity researchers.

METHODS

We introduce PREs as an intermediary design between randomized controlled trials and observational studies. We review previous research that used the PRE design and describe its application in obesity-related research, including random roommate assignments, heterochronic parabiosis, and the quasi-random assignment of subjects to geographic areas. We then provide a statistical framework to control for potential packet-level confounders not accounted for by randomization.

RESULTS

Packet randomized experiments have successfully been used to improve causal estimates of the effect of roommates, altitude, and breastfeeding on weight outcomes. When certain assumptions are met, PREs can asymptotically control for packet-level characteristics. This has the potential to statistically estimate the effect of a single treatment even when randomization to a single treatment did not occur.

CONCLUSIONS

Applying PREs to obesity-related research will improve decisions about clinical, public health, and policy actions insofar as it offers researchers new insight into cause and effect relationships among variables.

Weighing the Evidence of Common Beliefs in Obesity Research

Obesity is a topic on which many views are strongly held in the absence of scientific evidence to support those views, and some views are strongly held despite evidence to contradict those views. We refer to the former as "presumptions" and the latter as "myths." Here, we present nine myths and 10 presumptions surrounding the effects of rapid weight loss; setting realistic goals in weight loss therapy; stage of change or readiness to lose weight; physical education classes; breastfeeding; daily self-weighing; genetic contribution to obesity; the "Freshman 15"; food deserts; regularly eating (versus skipping) breakfast; eating close to bedtime; eating more fruits and vegetables; weight cycling (i.e., yo-yo dieting); snacking; built environment; reducing screen time in childhood obesity; portion size; participation in family mealtime; and drinking water as a means of weight loss. For each of these, we describe the belief and present evidence that the belief is widely held or stated, reasons to support the conjecture that the belief might be true, evidence to directly support or refute the belief, and findings from randomized controlled trials, if available. We conclude with a discussion of the implications of these determinations, conjecture on why so many myths and presumptions exist, and suggestions for limiting the spread of these and other unsubstantiated beliefs about the obesity domain.

Impaired range of motion of limbs and spine in chronic fatigue syndrome

OBJECTIVE

To determine whether adolescents and young adults with chronic fatigue syndrome (CFS) have a greater prevalence of impaired range of motion (ROM) of the limbs and spine than healthy control patients.

STUDY DESIGN

Case-control study comparing rates of abnormal ROM in 48 consecutive adolescents and young adults with CFS and 48 healthy control patients matched by sex and joint hypermobility. We examined range of ankle dorsiflexion, passive straight-leg raise, seated slump, upper-limb neurodynamic test, prone knee bend, and prone press-up. Abnormal ROM was defined before the study began. The number of abnormal responses ranged from 0 (normal ROM throughout) to 11 (impaired ROM in all areas tested).

RESULTS

The median number of areas with impaired ROM was greater in patients with CFS at the onset of stretch in the involved limb (5 vs 2, P<.001) and at end-range (2 vs 0, P<.001). Patients with CFS were more likely to have greater than 3 areas of impaired ROM (OR 6.0, 95% CI 2.1-17.3; P<.001) and were more likely to develop abnormal symptomatic responses to the individual tests and to the overall assessment (40% vs 4%; P<.001).

CONCLUSIONS

Impaired ROM is more common in subjects with CFS than in healthy adolescents and young adults matched by sex and joint hypermobility. Adding a longitudinal strain to the nerves and soft tissues provoked symptoms in some subjects with CFS. The causes, functional impact, and optimal treatment of these abnormalities warrant further study.

Obesity and mortality: are the risks declining? Evidence from multiple prospective studies in the United States

We evaluated whether the obesity-associated years of life lost (YLL) have decreased over calendar time. We implemented a meta-analysis including only studies with two or more serial body mass index (BMI) assessments at different calendar years. For each BMI category (normal weight: BMI 18.5 to <25 [reference]; overweight: BMI 25 to <30; grade 1 obesity: BMI 30 to <35; and grade 2-3 obesity: BMI ≥ 35), we estimated the YLL change between 1970 and 1990. Because of low sample sizes for African-American, results are reported on Caucasian. Among men aged ≤60 years YLL for grade 1 obesity increased by 0.72 years (P < 0.001) and by 1.02 years (P = 0.01) for grade 2-3 obesity. For men aged >60, YLL for grade 1 obesity decreased by 1.02 years (P < 0.001) and increased by 0.63 years for grade 2-3 obesity (P = 0.63). Among women aged ≤60, YLL for grade 1 obesity decreased by 4.21 years (P < 0.001) and by 4.97 years (P < 0.001) for grade 2-3 obesity. In women aged >60, YLL for grade 1 obesity decreased by 3.98 years (P < 0.001) and by 2.64 years (P = 0.001) for grade 2-3 obesity. Grade 1 obesity's association with decreased longevity has reduced for older Caucasian men. For Caucasian women, there is evidence of a decline in the obesity YLL association across all ages.

Hallucinogen use predicts reduced recidivism among substance-involved offenders under community corrections supervision

Hallucinogen-based interventions may benefit substance use populations, but contemporary data informing the impact of hallucinogens on addictive behavior are scarce. Given that many individuals in the criminal justice system engage in problematic patterns of substance use, hallucinogen treatments also may benefit criminal justice populations. However, the relationship between hallucinogen use and criminal recidivism is unknown. In this longitudinal study, we examined the relationship between naturalistic hallucinogen use and recidivism among individuals under community corrections supervision with a history of substance involvement (n=25,622). We found that hallucinogen use predicted a reduced likelihood of supervision failure (e.g. noncompliance with legal requirements including alcohol and other drug use) while controlling for an array of potential confounding factors (odds ratio (OR)=0.60 (0.46, 0.79)). Our results suggest that hallucinogens may promote alcohol and other drug abstinence and prosocial behavior in a population with high rates of recidivism.

Changes in Body Mass Index in Children with Juvenile Idiopathic Arthritis Treated with Tumor Necrosis Factor Inhibitors

Objective.

To evaluate changes in body mass index (BMI) among cohorts of children with juvenile idiopathic arthritis (JIA) with and without tumor necrosis factor (TNF) inhibitor therapy.

Methods.

We performed a retrospective chart review of children with JIA who newly initiated TNF inhibitor therapy and had at least 1 year of subsequent followup (TNF cohort). We also included children with JIA and at least 1 year of followup without any TNF inhibitor therapy (comparator cohort). Children with systemic arthritis were excluded. Age and sex specific BMI z-scores and their corresponding categories (normal, overweight, obese) were determined. We compared changes from a baseline visit to the last followup visit using t-test for BMI z-scores and chi square and Kruskal-Wallis tests for BMI categories.

Results.

The TNF cohort had 167 patients; the comparator cohort had 37. The median study followup was 2.8 and 2.2 years, respectively. The cohorts had similar age, sex, race, weight, and height distributions. The TNF cohort had a statistically significant increase in BMI z-score from baseline (+0.15; p = 0.02) that was not significantly different from the increase (+0.09) observed in the comparator cohort (p = 0.5). There was no significant change in the proportions of overweight and obese children in the TNF cohort compared to baseline (p = 0.6) or compared to the change in the comparator cohort (p = 0.2).

Conclusion.

Over more than 2 years of followup, we did not observe a significant increase in BMI among children with JIA receiving TNF inhibitor compared to those not receiving it.

Does obesity associate with mortality among Hispanic persons? Results from the National Health Interview Survey

OBJECTIVE

To evaluate the association between BMI: kg/m(2) and mortality among Hispanic adults.

DESIGN AND METHODS

Eight years (1997-2004) of National Health Interview Survey data linked to public-use mortality follow-up data through 2006 were acquired. Using Cox proportional hazards regression, separate models for two attained age strata (18 to <60 years, ≥60 years) adjusting for sex, smoking, and physical activity with over 38,000 analyzable respondents were fit.

RESULTS

Among those aged ≥60 years, underweight (BMI ≤ 18.5) associated with elevated mortality (hazard ratio [HR] = 2.19; 95% confidence interval [CI], 1.38-3.46), whereas overweight (BMI of 25 to <30) and obesity grade 1 (BMI of 30 to <35) associated with reduced mortality (HRs = 0.79; 95% CI, 0.65-0.95 and 0.71; 95% CI, 0.56-0.91), respectively. There were no significant associations between BMI and mortality among the 18 to <60 years attained age strata or among never smokers for either age strata.

CONCLUSIONS

Overweight and obesity are not obviously associated with elevated mortality among Hispanic adults.

Neuromuscular strain as a contributor to cognitive and other symptoms in chronic fatigue syndrome: hypothesis and conceptual model

Individuals with chronic fatigue syndrome (CFS) have heightened sensitivity and increased symptoms following various physiologic challenges, such as orthostatic stress, physical exercise, and cognitive challenges. Similar heightened sensitivity to the same stressors in fibromyalgia (FM) has led investigators to propose that these findings reflect a state of central sensitivity. A large body of evidence supports the concept of central sensitivity in FM. A more modest literature provides partial support for this model in CFS, particularly with regard to pain. Nonetheless, fatigue and cognitive dysfunction have not been explained by the central sensitivity data thus far. Peripheral factors have attracted attention recently as contributors to central sensitivity. Work by Brieg, Sunderland, and others has emphasized the ability of the nervous system to undergo accommodative changes in length in response to the range of limb and trunk movements carried out during daily activity. If that ability to elongate is impaired—due to movement restrictions in tissues adjacent to nerves, or due to swelling or adhesions within the nerve itself—the result is an increase in mechanical tension within the nerve. This adverse neural tension, also termed neurodynamic dysfunction, is thought to contribute to pain and other symptoms through a variety of mechanisms. These include mechanical sensitization and altered nociceptive signaling, altered proprioception, adverse patterns of muscle recruitment and force of muscle contraction, reduced intra-neural blood flow, and release of inflammatory neuropeptides. Because it is not possible to differentiate completely between adverse neural tension and strain in muscles, fascia, and other soft tissues, we use the more general term “neuromuscular strain.” In our clinical work, we have found that neuromuscular restrictions are common in CFS, and that many symptoms of CFS can be reproduced by selectively adding neuromuscular strain during the examination. In this paper we submit that neuromuscular strain is a previously unappreciated peripheral source of sensitizing input to the nervous system, and that it contributes to the pathogenesis of CFS symptoms, including cognitive dysfunction.

Mortality rate and overweight: Overblown or underestimated? A commentary on a recent meta-analysis of the associations of BMI and mortality

In this review, we discuss strengths and limitations of a recent rigorous systematic review and meta-analysis of the literature on associations of all-cause mortality with overweight and obesity. A perspective on its meaning and potential implications are provided. To move this field forward, we suggest modeling BMI as a continuous variable, switching to modeling longevity instead of mortality, and generating large publicly available datasets in broad and diverse populations for discerning the extent to which the BMI-mortality relationship differs between groups and over time. Randomized studies of obesity-related interventions that provide assessments of their actual effects on lifespan or mortality would have great value for helping to establish valid clinical and public health recommendations around weight loss and mortality.

Myths, presumptions, and facts about obesity

BACKGROUND

Many beliefs about obesity persist in the absence of supporting scientific evidence (presumptions); some persist despite contradicting evidence (myths). The promulgation of unsupported beliefs may yield poorly informed policy decisions, inaccurate clinical and public health recommendations, and an unproductive allocation of research resources and may divert attention away from useful, evidence-based information.

METHODS

Using Internet searches of popular media and scientific literature, we identified, reviewed, and classified obesity-related myths and presumptions. We also examined facts that are well supported by evidence, with an emphasis on those that have practical implications for public health, policy, or clinical recommendations.

RESULTS

We identified seven obesity-related myths concerning the effects of small sustained increases in energy intake or expenditure, establishment of realistic goals for weight loss, rapid weight loss, weight-loss readiness, physical-education classes, breast-feeding, and energy expended during sexual activity. We also identified six presumptions about the purported effects of regularly eating breakfast, early childhood experiences, eating fruits and vegetables, weight cycling, snacking, and the built (i.e., human-made) environment. Finally, we identified nine evidence-supported facts that are relevant for the formulation of sound public health, policy, or clinical recommendations.

CONCLUSIONS

False and scientifically unsupported beliefs about obesity are pervasive in both scientific literature and the popular press. (Funded by the National Institutes of Health.).

Muscle density in rheumatoid arthritis: associations with disease features and functional outcomes

OBJECTIVE

To explore the associations between measures of body composition derived from computed tomography (CT) of the thigh and functional outcomes in patients with rheumatoid arthritis (RA).

METHODS

Patients with RA underwent bilateral midfemoral quantitative CT for measurement of thigh fat area (TFA), thigh muscle area (TMA), and thigh muscle density (TMD). The associations of thigh-composition measures with disability and physical performance, as measured with the Health Assessment Questionnaire (HAQ), the Valued Life Activities (VLAs), and the Short Physical Performance Battery (SPPB) instruments, were explored in the total cohort and in the cohort subgrouped by sex, controlling for pertinent demographic, lifestyle, and RA disease and treatment covariates.

RESULTS

A total of 152 RA patients were studied. Among the potential determinants of TMD, older age, longer duration of sedentary activity, longer duration of RA, higher tender joint count, higher serum interleukin-6 levels, use of glucocorticoids, and nonuse of hydroxychloroquine were all significantly associated with lower TMD in multivariable models. RA characteristics accounted for 63% of the explainable variability in TMD. When comodeled, higher TFA and lower TMD, but not lower TMA, were significantly and independently associated with higher HAQ scores, lower Short Form 36 health survey physical functioning scores, lower composite SPPB scores, and a greater proportion of affected obligatory VLAs.

CONCLUSION

Thigh CT-derived measures of body composition, particularly fat area and muscle density, were strongly associated with disability and physical performance in RA patients, with RA disease features as potential determinants. Efforts to reduce fat and improve muscle quality may reduce disability in this population with impaired physical functioning.

Changes in pain catastrophizing predict later changes in fibromyalgia clinical and experimental pain report: cross-lagged panel analyses of dispositional and situational catastrophizing

Introduction

Fibromyalgia (FM), characterized by wide-spread diffuse pain and sensory abnormalities, is associated with elevated indices of distress and pain-related catastrophizing compared to both pain-free samples and those with chronic pain conditions. Catastrophizing is a pervasive negative mental set, and is a strong predictor of negative pain-related outcomes such as clinical pain intensity, and physical disability. Situational catastrophizing, measured in the context of experimentally-induced pain, is strongly related to enhanced pain sensitivity, a core aspect of the pathophysiology of fibromyalgia. However, little is known regarding the temporal course of the association between catastrophizing and pain-related "outcomes". Most studies involve only static assessments of pain and catastrophizing at a single time point, which provides little insight into the direction of the observed associations. We sought to investigate the temporal relationships between catastrophizing and indices of both clinical pain (substudy 1) and experimentally-induced pain (substudy 2) in a larger randomized controlled longitudinal trial.

Methods

Fifty-seven patients with FM completed catastrophizing, depression, and pain questionnaires as well as laboratory cold pressor pain testing at baseline, post-intervention and three month follow-up during a lifestyle physical activity study. Cross-lagged panel analyses were used to address these temporal relationships.

Results

In substudy 1, analyses revealed that pre-to-post changes in dispositional catastrophizing ratings prospectively accounted for unique variance in subsequent post-to-follow-up changes in clinical pain ratings (p = 0.005), while pre-to-post changes in pain ratings did not account for unique variance in post-to-follow-up changes in catastrophizing ratings. An identical pattern was observed experimentally in substudy 2, with pre-to-post changes in situational catastrophizing ratings prospectively accounting for unique variance in subsequent post-to-follow-up changes in experimental pain ratings (p = 0.014), while pre-to-post changes in pain ratings did not account for unique variance in post-to-follow-up changes in catastrophizing ratings. Specifically, initial alterations in catastrophizing were associated with subsequent alterations in clinical and experimentally induced pain. Controlling for levels of depression did not affect the results.

Conclusions

These findings provide empirical evidence that catastrophizing processes might precede and contribute to subsequent alterations in the pain experience for FM patients.

Trial Registration

clinicaltrials.gov: NCT00383084.

Relationship between Body Weight Gain and Significant Knee, Hip, and Back Pain in Older Americans

OBJECTIVE

To examine the association between BMI (kilograms per meter squared) and reports of significant knee, hip, and back pain using data from a nationally representative sample of U.S. adults 60 years or older.

RESEARCH METHODS AND PROCEDURES

Population-based survey data from the Third National Health and Nutrition Examination Survey, involving 5724 adults 60 years or older, were used. BMI, calculated from measured weight (kilograms) and height (meters squared), was used to categorize participants into six BMI-defined groups: underweight (<18.5), desirable weight (18.5 to 24.9), overweight (25 to 29.9), obese class I (30 to 34.9), obese class II (35 to 39.9), and obese class III (>/=40). The presence of significant knee, hip, and back pain in the groups was studied.

RESULTS

The overall prevalences of knee, hip, and back pain were 21%, 14%, and 22%, respectively. Prevalence estimates for knee (underweight 12.1% to obesity class III 55.7%), hip (underweight 10.4% to obesity class III 23.3%), and back (underweight 20.2% to obesity class III 26.1%) pain increased with increased BMI. Sex-, race-, and age-specific pain prevalence estimates also generally increased at increased levels of BMI.

DISCUSSION

Among U.S. adults 60 years or older, the prevalence of significant knee, hip, and back pain increases with increased levels of BMI.

Is funding source related to study reporting quality in obesity or nutrition randomized control trials in top-tier medical journals?

BACKGROUND

Faithful and complete reporting of trial results is essential to the validity of the scientific literature. An earlier systematic study of randomized controlled trials (RCTs) found that industry-funded RCTs appeared to be reported with greater quality than non-industry-funded RCTs. The aim of this study was to examine the association between systematic differences in reporting quality and funding status (that is, industry funding vs non-industry funding) among recent obesity and nutrition RCTs published in top-tier medical journals.

METHODS

Thirty-eight obesity or nutrition intervention RCT articles were selected from high-profile, general medical journals (The Lancet, Annals of Internal Medicine, JAMA and the British Medical Journal) published between 2000 and 2007. Paired papers were selected from the same journal published in the same year, one with and the other without industry funding. The following identifying information was redacted: journal, title, authors, funding source and institution(s). Then three raters independently and blindly rated each paper according to the Chalmers method, and total reporting quality scores were calculated.

FINDINGS

The inter-rater reliability (Cronbach's alpha) was 0.82 (95% confidence interval = 0.80-0.84). The total mean (M) and s.d. of Chalmers Index quality score (out of a possible 100) for industry-funded studies were M = 84.5, s.d. = 7.04 and for non-industry-funded studies they were M = 79.4, s.d. = 13.00. A Wilcoxon matched-pairs signed-ranks test indicates no significant rank difference in the distributions of total quality scores between funding sources, Z = -0.966, P = 0.334 (two tailed).

INTERPRETATION

Recently published RCTs on nutrition and obesity that appear in top-tier journals seem to be equivalent in quality of reporting, regardless of funding source. This may be a result of recent reporting of quality statements and efforts of journal editors to raise all papers to a common standard.

Use of self-reported height and weight biases the body mass index-mortality association

Background

Many large-scale epidemiologic data sources used to evaluate the body mass index (BMI: kg/m²) mortality association have relied on BMI derived from self-reported height and weight. Although measured BMI (BMI_M) and self-reported BMI (BMI_SR) correlate highly, self-reports are systematically biased.

Objective

To rigorously examine how self-reporting bias influences the association between BMI and mortality rate.

Subjects

Samples representing the US non-institutionalized civilian population.

Design and Methods

National Health and Nutrition Examination Survey data (NHANES II: 1976-80; NHANES III: 1988-94) contain BMI_M and BMI_SR. We applied Cox regression to estimate mortality hazard ratios (HRs) for BMI_M and BMI_SR categories, respectively, and compared results. We similarly analyzed subgroups of ostensibly healthy never-smokers.

Results

Misclassification by BMI_SR among the underweight and obesity ranged from 30–40% despite high correlations between BMI_M and BMI_SR (r>0.9). The reporting bias was moderately correlated with BMI_M (r>0.35), but not BMI_SR (r<0.15). Analyses using BMI_SR failed to detect six of eight significant mortality HRs detected by BMI_M. Significantly biased HRs were detected in the NHANES II full dataset (χ² = 12.49; p = 0.01) and healthy subgroup (χ² = 9.93; p = 0.04), but not in the NHANES III full dataset (χ² = 5.63; p = 0.23) or healthy subgroup (χ² = 1.52; p = 0.82).

Conclusions

BMI_SR should not be treated as interchangeable with BMI_M in BMI-mortality analyses. Bias and inconsistency introduced by using BMI_SR in place of BMI_M in BMI-mortality estimation and hypothesis tests may account for important discrepancies in published findings.

Association of body fat with C-reactive protein in rheumatoid arthritis

OBJECTIVE

The serum C-reactive protein (CRP) concentration is commonly used in rheumatoid arthritis (RA) as a surrogate marker of systemic inflammation, presumably induced by synovitis. However, other tissues, such as adipose tissue, can induce CRP production. This study was undertaken to explore the associations between measures of adiposity and CRP levels in RA.

METHODS

One hundred ninety-six men and women with RA underwent anthropometric assessment and total body dual-energy x-ray absorptiometry for measurement of total and regional body fat and lean mass. The associations between measures of fat and lean mass and serum levels of CRP and interleukin-6 (IL-6) were determined in analyses stratified by sex, with adjustment for pertinent demographic, lifestyle, and RA disease and treatment covariates as well as for the potential modifying effects of articular activity and biologic pharmacotherapeutic agents.

RESULTS

All measures of adiposity were significantly associated with the level of CRP in women, but not in men. In women, the measure of adiposity that showed the strongest association with the CRP level was truncal fat, in which, in adjusted analyses, each kilogram increase was associated with a 0.101-unit increase in the logarithmically transformed CRP level (P < 0.001). Neither the level of articular activity nor the use of biologic agents significantly modified this association in women. However, in men, elevated articular involvement was associated with a decreasing CRP level as truncal fat increased. For all analyses, substitution of IL-6 for CRP produced similar findings.

CONCLUSION

Adiposity is independently associated with CRP levels in women with RA, and thus may confound the estimation of RA disease activity when serum CRP concentration is used as a surrogate for systemic inflammation.

Effects of lifestyle physical activity on perceived symptoms and physical function in adults with fibromyalgia: results of a randomized trial

Introduction

Although exercise is therapeutic for adults with fibromyalgia (FM), its symptoms often create obstacles that discourage exercise. We evaluated the effects of accumulating at least 30 minutes of self-selected lifestyle physical activity (LPA) on perceived physical function, pain, fatigue, body mass index, depression, tenderness, and the six-minute walk test in adults with FM.

Methods

Eighty-four minimally active adults with FM were randomized to either LPA or a FM education control (FME) group. LPA participants worked toward accumulating 30 minutes of self-selected moderate-intensity LPA, five to seven days per week, while the FME participants received information and support.

Results

Seventy-three of the 84 participants (87%) completed the 12-week trial. The LPA group increased their average daily steps by 54%. Compared to FME, the LPA group reported significantly less perceived functional deficits (P = .032) and less pain (P = .006). There were no differences between the groups on the six-minute walk test (P = .067), fatigue, depression, body mass index, or tenderness.

Conclusions

Accumulating 30 minutes of LPA throughout the day produces clinically relevant changes in perceived physical function and pain in previously minimally active adults with FM.

Trial Registration

clinicaltrials.gov NCT00383084

Ten putative contributors to the obesity epidemic

The obesity epidemic is a global issue and shows no signs of abating, while the cause of this epidemic remains unclear. Marketing practices of energy-dense foods and institutionally-driven declines in physical activity are the alleged perpetrators for the epidemic, despite a lack of solid evidence to demonstrate their causal role. While both may contribute to obesity, we call attention to their unquestioned dominance in program funding and public efforts to reduce obesity, and propose several alternative putative contributors that would benefit from equal consideration and attention. Evidence for microorganisms, epigenetics, increasing maternal age, greater fecundity among people with higher adiposity, assortative mating, sleep debt, endocrine disruptors, pharmaceutical iatrogenesis, reduction in variability of ambient temperatures, and intrauterine and intergenerational effects as contributing factors to the obesity epidemic are reviewed herein. While the evidence is strong for some contributors such as pharmaceutical-induced weight gain, it is still emerging for other reviewed factors. Considering the role of such putative etiological factors of obesity may lead to comprehensive, cause specific, and effective strategies for prevention and treatment of this global epidemic.

Cardiac magnetic resonance imaging with pharmacological stress perfusion and delayed enhancement in asymptomatic patients with systemic sclerosis

OBJECTIVE

To assess cardiac involvement in asymptomatic patients with systemic sclerosis (SSc) by cardiac magnetic resonance imaging (MRI).

METHODS

Ten asymptomatic patients with SSc (all female; mean age 59.5+/-9.4 yrs) underwent contrast enhanced cardiac MRI on a 1.5 T MRI device. Adenosine triphosphate was used for stress and rest perfusion to assess perfusion defects due to microvascular impairment or ischemia, and delayed enhanced (DE) imaging was obtained for the assessment of myocardial necrosis and fibrosis. We evaluated the pathophysiological associations of stress perfusion combined with DE imaging with SSc disease severity measures.

RESULTS

Stress perfusion defects were seen in 5 out of 9 patients (56%): 4 had nonsegmental subendocardial perfusion defects and one had a segmental subendocardial perfusion defect. Three patients were found to have DE. DE was not observed in any patient without perfusion defect; and among the 5 patients with perfusion defects, 3 (60%) had DE. Two of the 3 had DE in segments not matching the region of nonsegmental perfusion defects. The remaining one had a segmental subendocardial DE matching the region of a segmental perfusion defect. Perfusion defects were seen in 75% of patients with a history of digital ulceration compared to only 20% of those without history of ulceration.

CONCLUSION

Subclinical myocardial involvement, as detected by cardiac MRI, was frequent in asymptomatic patients with SSc. Cardiac MRI may aid in understanding the pathophysiological mechanism of SSc.

Population projection of US adults with lifetime experience of depressive disorder by age and sex from year 2005 to 2050

OBJECTIVE

To estimate the projected population of US adults aged 18 years or older with lifetime experience of doctor-diagnosed depressive disorder from 2005-2050.

METHODS

Based on nationally representative survey data from the year 2006 Behavioral Risk Factor Surveillance Survey (BRFSS), prevalence estimates of doctor-diagnosed depression (minor or major, and dysthymia) were weighted to incorporate the complex sampling design and increase generalizability of the findings. The weighted prevalence data by age and sex in 2006 were then used to estimate the projected adult population with lifetime experience of depressive disorder based on the sex-specific US Census national population projections from year 2005-2050.

RESULTS

In year 2006 the (weighted) prevalence of lifetime experience of depressive disorder was 15.7% among 188,292 respondents aged 18 years or older. Female prevalence was 20.6%, which was about twice as high as the prevalence among males (11%). From year 2005-2050, the total number of US adults with depressive disorder will increase from 33.9 million to 45.8 million, a 35% increase. The increase is projected to be greater in the elderly population aged >or=65 years (3.8-8.2, a 117% increase) than in the young population aged <65 years (30.1-37.7, a 25% increase).

CONCLUSIONS

By year 2050, approximately 46 million US adults aged 18 years or older will be diagnosed with a depressive disorder. The increase will be more pronounced in adults aged 65 or older. Prevention, detection, and treatment of depressive disorders might attenuate the magnitude of this estimate.

Association of body composition with disability in rheumatoid arthritis: impact of appendicular fat and lean tissue mass

OBJECTIVE

To explore the association of measures of body composition with disability in patients with rheumatoid arthritis (RA).

METHODS

Patients with RA underwent total body dual-energy x-ray absorptiometry for measurement of total and regional body fat and lean mass. The associations of measures of fat and lean mass with disability, measured with the Health Assessment Questionnaire (HAQ), were explored for the total cohort and by sex, controlling for pertinent demographic, lifestyle, and RA disease and treatment covariates.

RESULTS

We studied 197 subjects (118 women, 79 men). Median (interquartile range) HAQ score was 0.625 (0.125-1.25) and was significantly higher, indicating worse physical function, in women than in men. HAQ score was strongly correlated with depression, pain, RA duration, duration of morning stiffness, Disease Activity Score in 28 joints, radiographic damage scores, levels of physical and sedentary activities, and body composition, with increasing fat and decreasing lean mass associated with higher HAQ scores. Appendicular fat and lean mass demonstrated the strongest association per kilogram with HAQ. Mean HAQ score was 0.52 units higher for subjects in the highest versus the lowest quartile of appendicular fat mass (P<0.001), and 0.81 units higher for subjects in the lowest versus the highest quartile of appendicular lean mass (P<0.001). Adjusting for demographic and RA characteristics partially attenuated these associations. The joint associations of appendicular fat and lean mass on HAQ were additive without significant interaction.

CONCLUSION

Body composition, particularly the amount of fat and lean mass located in the arms and legs, is strongly associated with disability in RA patients.

Abnormal body composition phenotypes in older rheumatoid arthritis patients: association with disease characteristics and pharmacotherapies

OBJECTIVE

To compare measures of body fat and lean mass and the prevalence of abnormal body composition phenotypes (sarcopenia, overfat, and sarcopenic obesity) in men and women with rheumatoid arthritis (RA) versus matched controls, and to explore the disease-related predictors of abnormal body composition in patients with RA.

METHODS

A total of 189 men and women with RA and 189 age-, sex-, and race-matched non-RA controls underwent dual-energy x-ray absorptiometry for measurement of total and regional body fat and lean mass. Continuous and categorical measures of body composition were compared between RA and control subjects by sex and according to categories of body mass index (BMI). Within the group of RA patients, demographic, lifestyle, and RA disease and treatment characteristics were compared for RA patients with healthy body composition versus those with abnormal body composition phenotypes.

RESULTS

Compared with non-RA controls, RA status was significantly associated with greater odds of sarcopenia, overfat, and sarcopenic obesity in women, but not in men. Relative differences in body composition phenotypes between RA and control subjects were greatest for patients in the normal weight BMI category (<25 kg/m(2)). Among RA characteristics, increasing joint deformity, self-reported disability scores, C-reactive protein levels, rheumatoid factor seropositivity, and a lack of current treatment with disease-modifying antirheumatic drugs were significantly associated with abnormal body composition.

CONCLUSION

Abnormal body composition phenotypes are overrepresented in patients with RA, particularly in those in the normal weight BMI range. RA-associated disease and treatment characteristics contribute to this increase in abnormal body composition.