Racial Differences in Weight Loss Among Adults in a Behavioral Weight Loss Intervention: Role of Diet and Physical Activity

The impact of a low-carbohydrate (vs. low-fat) diet on fat mass loss in African American women is modulated by insulin sensitivity

OBJECTIVE

The objective of this study was to examine the independent and interactive effects of insulin sensitivity (SI), the acute insulin response to glucose, and diet on changes in fat mass (FM), resting and total energy expenditure (REE and TEE, respectively), and mechanical efficiency, during weight loss, in African American women with obesity.

METHODS

A total of 69 women were randomized to low-fat (55% carbohydrate [CHO], 20% fat) or low-CHO (20% CHO, 55% fat) hypocaloric diets for 10 weeks, followed by a 4-week weight-stabilization period (controlled feeding). SI and acute insulin response to glucose were measured at baseline with an intravenous glucose tolerance test; body composition was measured with bioimpedance analysis at baseline and week 10; and REE, TEE, and mechanical efficiency were measured with indirect calorimetry, doubly labeled water, and a submaximal bike test, respectively, at baseline and week 14.

RESULTS

Within the group with low SI, those on the low-CHO diet lost more weight (mean [SE], -6.6 [1.0] vs. -4.1 [1.4] kg; p = 0.076) and FM (-4.9 [0.9] vs. -2.1 [1.0] kg; p = 0.04) and experienced a lower reduction in REE (-48 [30] vs. -145 [30] kcal/day; p = 0.035) and TEE (mean [SE] 67 [56] vs. -230 [125] kcal/day; p = 0.009) compared with those on the low-fat diet.

CONCLUSIONS

A low-CHO diet leads to a greater FM loss in African American women with obesity and low SI, likely by minimizing the reduction in EE that follows weight loss.

Cardiovascular disease risk: it is complicated, but race and ethnicity are key, a Bayesian network analysis

Background

Cardiovascular diseases are the leading cause of morbidity and mortality in the United States. Despite the complexity of cardiovascular disease etiology, we do not fully comprehend the interactions between non-modifiable factors (e.g., age, sex, and race) and modifiable risk factors (e.g., health behaviors and occupational exposures).

Objective

We examined proximal and distal drivers of cardiovascular disease and elucidated the interactions between modifiable and non-modifiable risk factors.

Methods

We used a machine learning approach on four cohorts (2005-2012) of the National Health and Nutrition Examination Survey data to examine the effects of risk factors on cardiovascular risk quantified by the Framingham Risk Score (FRS) and the Pooled Cohort Equations (PCE). We estimated a network of risk factors, computed their strength centrality, closeness, and betweenness centrality, and computed a Bayesian network embodied in a directed acyclic graph.

Results

In addition to traditional factors such as body mass index and physical activity, race and ethnicity and exposure to heavy metals are the most adjacent drivers of PCE. In addition to the factors directly affecting PCE, sleep complaints had an immediate adverse effect on FRS. Exposure to heavy metals is the link between race and ethnicity and FRS.

Conclusion

Heavy metal exposures and race/ethnicity have similar proximal effects on cardiovascular disease risk as traditional clinical and lifestyle risk factors, such as physical activity and body mass. Our findings support the inclusion of diverse racial and ethnic groups in all cardiovascular research and the consideration of the social environment in clinical decision-making.

Disparities in Race and Ethnicity Reporting and Representation for Clinical Trials in Stroke: 2010 to 2020

BACKGROUND

Racial and ethnic minority groups are at a higher stroke risk and have poor poststroke outcomes. The aim of this study was to assess the frequency of race reporting and proportions of race and ethnicity representation in stroke-related clinical trials.

METHODS AND RESULTS

This is a descriptive study of stroke-related clinical trials completed between January 1, 2010 and December 31, 2020, and registered on ClinicalTrials.gov. Trials conducted in the United States, related to stroke and enrolling participants ≥18 years, were considered eligible. Trials were reviewed for availability of published results, data on race and ethnicity distribution, and trial characteristics. Overall, 60.1% of published trials reported race or ethnicity of participants, with a 2.6-fold increase in reporting between 2010 and 2020. White patients represented 65.0% of the participants, followed by 24.8% Black, 2.4% Asian or Pacific Islander, and <1% Native American and multiracial participants; 9.0% were of Hispanic ethnicity. These trends remained consistent throughout the study period, except in 2018, when a higher proportion of Black participants (53.1%) was enrolled compared with White participants (35.8%). Trials with the National Institutes of Health/federal funding had higher enrollment of Black (28.1%) and Hispanic (13.8%) participants compared with other funding sources. Behavioral intervention trials had the most diverse enrollment with equal enrollment of Black and White participants (41.1%) and 14.5% Hispanic participants.

CONCLUSIONS

Despite the increase in race and ethnicity reporting between 2010 and 2020, the representation of racial and ethnic minority groups remains low in stroke trials. Funding initiatives may influence diversity efforts in trial enrollment.

Predictors of racial differences in weight loss: the PROPEL trial

OBJECTIVE

Studies have consistently shown that African American individuals lose less weight in response to behavioral interventions, but the mechanisms leading to this result have been understudied.

METHODS

Data were derived from the PROmoting Successful Weight Loss in Primary CarE in Louisiana (PROPEL) study, which was a cluster-randomized, two-arm trial conducted in primary care clinics. In the PROPEL trial, African American individuals lost less weight compared with patients who belonged to other racial groups after 24 months. In the current study, counterfactual mediation analyses among 445 patients in the intervention arm of PROPEL were used to determine which variables mediated the relationship between race and weight loss. The mediators included treatment engagement, psychosocial, and lifestyle factors.

RESULTS

At 6 months, daily weighing mediated 33% (p = 0.008) of the racial differences in weight loss. At 24 months, session attendance and daily weighing mediated 35% (p = 0.027) and 66% (p = 0.005) of the racial differences in weight loss, respectively. None of the psychosocial or lifestyle variables mediated the race-weight loss association.

CONCLUSIONS

Strategies specifically targeting engagement, such as improving session attendance and self-weighing behaviors, among African American individuals are needed to support more equitable weight losses over extended time periods.

Associations between behaviour change technique clusters and weight loss outcomes of automated digital interventions: a systematic review and meta-regression

Automated digital interventions for weight loss represent a highly scalable and potentially cost-effective approach to treat obesity. However, current understanding of the active components of automated digital interventions is limited, hindering efforts to improve efficacy. Thus, the current systematic review and meta-analysis (preregistration: PROSPERO 2021-CRD42021238878) examined relationships between utilisation of behaviour change techniques (BCTs) and the efficacy of automated digital interventions for producing weight loss. Electronic database searches (December 2020 to March 2021) were used to identify trials of automated digital interventions reporting weight loss as an outcome. BCT clusters were coded using Michie's 93-item BCT taxonomy. Mixed-effects meta-regression was used to examine moderating effects of BCT clusters and techniques on both within-group and between-group measures of weight change. One hundred and eight conditions across sixty-six trials met inclusion criteria (13,672 participants). Random-effects meta-analysis revealed a small mean post-intervention weight loss of -1.37 kg (95% CI, -1.75 to -1.00) relative to control groups. Interventions utilised a median of five BCT clusters, with goal-setting, feedback and providing instruction on behaviour being most common. Use of Reward and Threat techniques, and specifically social incentive/reward BCTs, was associated with a higher between-group difference in efficacy, although results were not robust to sensitivity analyses.

Variation by race/ethnicity in the utilization and weight loss following metabolic bariatric surgery

BACKGROUND

Understanding the disparities in utilization and weight loss outcomes of metabolic and bariatric surgery (MBS) by demographics will inform strategies targeting potential treatment gaps and enhance overall clinical obesity treatment.

OBJECTIVE

To identify factors associated with utilization and longitudinal weight loss after MBS.

SETTING

OneFlorida Clinical Research Consortium Database.

METHODS

We performed a retrospective study using data from the OneFlorida Clinical Research Consortium between 2012 and 2018. We used logistic regression with intersectional effects to identify factors associated with utilization of MBS. Mixed-effect models were used to estimate longitudinal percentage total weight loss among those who underwent MBS with up to 18 months of follow-up.

RESULTS

Among 429,821 patients eligible for MBS, 8290 (1.9%) underwent MBS between 2012 and 2018. Intersectional analysis revealed that non-Hispanic Black patients experienced an inferior utilization of MBS compared with non-Hispanic White and Hispanic counterparts, defined by the interaction between race/ethnicity and demographic factors, including male sex, older age, and insurance coverage. In the longitudinal weight loss assessment, 4016 patients (48.3% Roux-en-Y gastric bypass, 51.7% sleeve gastrectomy) were included. We found that non-Hispanic Black patients experienced significantly less weight loss than non-Hispanic White and Hispanic counterparts. Other factors associated with less weight loss over time included undergoing sleeve gastectomy, male sex, lower preoperative body mass index, and having type 2 diabetes at the time of surgery.

CONCLUSIONS

Our findings will help to design new strategies focusing on the intersection of race/ethnicity and sociodemographic factors to improve access and effectiveness of MBS.

Factors that predict weight loss success differ by diet intervention type

Background

Many types of diet intervention can achieve negative energy balance and successful weight loss in persons with obesity. However, within any dietary strategy, there is large inter-individual variation in the weight loss response. The aim of this study is to determine factors that predict weight loss success for diet interventions that vary by macronutrient and caloric composition.

Methods

Participants with BMI 30.0 to 49.9 kg/m2 self-selected one of three diet intervention trials for weight loss: low carbohydrate (LOW CHO), low fat (LOW FAT), or low calorie (LOW KCAL). Multivariable regression models were developed to determine the significance of predictor demographic, body composition, metabolic, clinical, and dietary variables for each diet type.

Results

Weight loss over 12-16 weeks averaging -5.1 ± 4.0 kg from baseline weight, p < 0.001, was not significantly different among diet types. Several different factors were identified that account for the inter-individual variance in weight loss success. Regardless of diet type, the most robust predictor of weight loss success was completion of the intervention, accounting for 20-30% of the variance. Factors predicting diet intervention completion were age, physical activity level, blood leptin level, blood pressure, and the amount of weight loss occurring. Differences by diet type in cardiometabolic risk factor reduction were identified with LOW CHO decreasing glycemia/insulinemia factors, LOW FAT decreasing lipidemia factors, and LOW KCAL decreasing inflammatory factors.

Conclusion

These data provide evidence to inform more precise and personalized approaches to diet intervention for weight loss and cardiometabolic health.

Impacto de los diferentes tipos de entrenamiento físico sobre la composición corporal en mujeres adultas con obesidad: una revisión bibliográfica

Introducción: La obesidad sigue siendo uno de los problemas más grandes de salud pública en todo el mundo. Se conoce que está asociada con una gran variedad de enfermedades; en mujeres obesas, aún se desconoce la forma idónea para realizar una adecuada prescripción física. Objetivo: revisar los tipos de entrenamientos físicos de ensayos controlados aleatorizados publicados en la base de datos PubMed entre los años 2015 a 2022 sobre los cambios en la composición corporal en mujeres adultas de 18 a 65 años con obesidad. Metodología: se utilizó a modo de filtro la “Herramienta de Evaluación de Calidad Validada para Estudios Cuantitativos”. Resultados: la búsqueda arrojó 586 artículos, de los cuales el 93.85% fueron eliminados; 6.14% pasaron por un filtro que dejó un total de 1.7%. Conclusión: en mujeres adultas con obesidad, se ha demostrado que todos los tipos de entrenamiento físico sirven para generar cambios en la composición corporal. Introduction: Obesity continues to be one of the biggest public health problems worldwide. It is known to be associated with a wide variety of diseases; in obese women, the ideal way to carry out an adequate physical prescription is still unknown. Objective: to review the types of physical training in randomized controlled trials published in the PubMed database between 2015 and 2022 on changes in body composition in adult women aged 18 to 65 with obesity. Methodology: the "Validated Quality Assessment Tool for Quantitative Studies" was used as a filter. Outcomes: the search yielded 586 articles, of which 93.85% were eliminated; 6.14% went through a filter that left a total of 1.7%. Conclusion: in adult women with obesity, it has been shown that all types of physical training serve to generate changes in body composition.

Telehealth acceptance and commitment therapy for weight loss: Protocol of the WeLNES full scale randomized controlled trial

Behavioral interventions delivered via one-on-one telephone coaching (hereafter referred to as telehealth) for weight loss have had great population-level reach but to date limited efficacy. Acceptance and Commitment Therapy (ACT) has promise to improve behavioral weight loss treatment efficacy by addressing the fundamental challenges of weight loss and maintenance: overeating in response to internal (e.g., stress) and external (e.g., high calorie foods) cues. Here we describe the Weight Loss, Nutrition, and Exercise Study (WeLNES) randomized controlled trial that is testing the efficacy of an ACT-based telehealth coaching intervention for weight loss in comparison to a Standard Behavioral Therapy (SBT)-based telehealth coaching intervention. A total of 398 adults with overweight or obesity are being recruited and randomized to either ACT or SBT telehealth coaching. Participants in both arms are offered twenty-five telehealth coaching sessions in year one and nine booster sessions in year two. All participants receive a Bluetooth-enabled scale to self-monitor weight and a Fitbit Inspire + Fitbit app for tracking diet and physical activity. The primary aim is to determine whether a greater proportion of ACT participants will achieve a clinically significant weight loss of ≥10% compared with SBT participants at 12-months. Secondary outcomes include change in weight from baseline to 6, 12, and 24-months. Whether the effect of ACT on weight loss is mediated by ACT processes and is moderated by baseline factors will also be examined. If ACT proves efficacious, ACT telehealth coaching will offer an effective, broadly scalable weight loss treatment-thereby making a high public health impact.

Effect of a Plant-Based vs Omnivorous Soul Food Diet on Weight and Lipid Levels Among African American Adults: A Randomized Clinical Trial

IMPORTANCE

More African American individuals die from cardiovascular disease (CVD) than any other chronic disease condition. Despite this disparity, African American individuals are underrepresented in nutrition and CVD interventions.

OBJECTIVE

To compare the effects of an entirely plant-based (vegan) or low-fat omnivorous (omni) diet on change in body weight and lipids during a 2-year intervention.

DESIGN, SETTING, AND PARTICIPANTS

The Nutritious Eating With Soul (NEW Soul) study was a 2-year, randomized clinical trial conducted in 2 cohorts (2018-2020 and 2019-2021) that took place in a university teaching kitchen in Columbia, South Carolina (before March 2020), and via online videoconference sessions (after March 2020). Participants included African American adults aged 18 to 65 years with overweight or obesity (body mass index of 25.0-49.9) and without type 2 diabetes, uncontrolled thyroid disease, recent weight loss, or pregnancy. Data assessors and statisticians were blinded to study condition. Data analysis was performed from March to June 2022.

INTERVENTIONS

The intervention included weekly nutrition classes for 6 months biweekly classes for 6 months, and monthly classes for 12 months. Dietary interventions either emphasized no animal product intake (vegan) or a low-fat omnivorous diet (omni). Both dietary patterns emphasized soul food cuisine (traditional African American southern foodways).

MAIN OUTCOMES AND MEASURES

Primary outcomes included change in body weight and lipid measures at 12 months.

RESULTS

There were 568 participants who completed an online screening questionnaire; 409 were excluded and 159 were randomized (77 to the vegan group and 82 to the omni group). Of the 159 participants (mean [SD] age, 48.4 [10.6] years; 126 female [79%]) who began the study, the main outcome of body weight was obtained for 121 participants (76%) at 12 months. There were no differences in outcomes between groups, including 12-month changes in weight (mean, -2.39 kg [95% CI, -3.48 to -1.30 kg] for the vegan group vs -2.03 kg [95% CI, -3.07 to -1.00 kg] for the omni group; P = .64), total cholesterol (-1.05 mg/dL [95% CI, -9.60 to 7.50 mg/dL] for the vegan group vs 1.66 mg/dL [95% CI, -7.20 to 10.50 mg/dL] for the omni group; P = .67), or low-density lipoprotein cholesterol (mean, -2.56 mg/dL [95% CI, -9.52 to 4.40 mg/dL] for the vegan group vs -0.79 mg/dL [95% CI, -7.98 to 6.40 mg/dL] for the omni group; P = .73). Weight loss at 12 months among cohort 1, whose weight was assessed in 2019 before the COVID-19 pandemic, was significantly greater than that for cohort 2, whose weight was assessed summer 2020 during COVID-19 (-3.45 kg [95% CI, -4.67 to -2.22 kg] vs -1.24 kg [95% CI, -2.24 to -0.25 kg]; P = .01).

CONCLUSIONS AND RELEVANCE

In this randomized clinical trial examining weight loss and CVD risk factor reduction among African American adults, there were no differences between the groups, and the magnitude of changes overall was small.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03354377.

Pretreatment and During-Treatment Weight Trajectories in Black and White Women

INTRODUCTION

Black participants often lose less weight than White participants in response to behavioral weight-loss interventions. Many participants experience significant pretreatment weight fluctuations (between baseline measurement and treatment initiation), which have been associated with treatment outcomes. Pretreatment weight gain has been shown to be more prevalent among Black participants and may contribute to racial differences in treatment responses. The purpose of this study was to (1) examine the associations between pretreatment weight change and treatment outcomes and (2) examine racial differences in pretreatment weight change and weight loss among Black and White participants.

METHODS

Participants were Black and White women (n=153, 60% Black) enrolled in a 4-month weight loss program. Weight changes occurring during the pretreatment period (41 ± 14 days) were categorized as weight stable (±1.15% of baseline weight), weight gain (≥+1.15%), or weight loss (≤-1.15%). Recruitment and data collection occurred from 2011 to 2015; statistical analyses were performed in 2021.

RESULTS

During the pretreatment period, most participants (56%) remained weight stable. Pretreatment weight trajectories did not differ by race (p=0.481). At 4-months, those who lost weight before treatment experienced 2.63% greater weight loss than those who were weight stable (p<0.005), whereas those who gained weight before treatment experienced 1.91% less weight loss (p<0.01).

CONCLUSIONS

Pretreatment weight changes can impact weight outcomes after initial treatment, although no differences between Black and White participants were observed. Future studies should consider the influence of pretreatment weight change on long-term outcomes (e.g., weight loss maintenance) along with potential racial differences in these associations. This study is registered (retrospectively registered) at ClinicalTrials.gov (NCT02487121) on June 26, 2015.

The Multi-Caregiver Role and Its Relationship to Behavioral Adherence and Weight Among Treatment Engaged Black Women

PURPOSE

To examine the relationship between the multiple caregiver role and its perceived barriers to self-care on behavioral adherence in a weight loss intervention.

DESIGN

A secondary analysis of data from a behavioral weight loss intervention.

SETTING

The study was conducted in two cohorts from March 2016 to February 2017 at the University of North Carolina at Chapel Hill.

SUBJECTS

Eighty-one Black women with overweight/obesity (age = 48.4 ± 10.9 years [M ± SD], BMI = 36.4 ± 4.5 kg/m² [M ± SD]).

MEASURES

Identification with the multiple caregiver role and barriers was assessed with the Multiple Caregiving Measurement Instrument. Weight was measured with a digital scale and height with a stadiometer. The Block food frequency questionnaire evaluated dietary intake. Moderate-to-vigorous physical activity (MVPA) was measured objectively with an accelerometer. Study adherence was measured by session attendance, self-weighing, and self-monitoring (diet and physical activity) frequency.

ANALYSIS

Generalized linear models were used to examine the relationship between the multiple caregiver scales and the outcomes of interest, controlling for study arm, cohort, and income. Chi-square tests tested correlations.

RESULTS

Greater identification with the multiple caregiver role was associated with decreased session attendance (β = -.56 [SE = .27], P < .05) and a trend towards weight gain (β = .36, [SE = .19], P = .07). Greater multiple caregiver barriers score predicted a decrease in fruit/vegetable intake (β = -.17 [SE = .07], P < .05). All regression results are unstandardized. Negative correlations between multiple caregiver barriers and MVPA (r = -.24, P = .06) and daily self-weighing (r = -.19, P = .10) approached significance.

CONCLUSIONS

Participants' identification with multiple caregiving role and barriers can reduce adherence, behavior and weight change. Interventions to address Black women's multiple roles and barriers during weight loss are needed to maximize outcomes.

Responding to Health Disparities in Behavioral Weight Loss Interventions and COVID-19 in Black Adults: Recommendations for Health Equity

COVID-19 has disproportionately impacted Black adults with high prevalence and mortality rates. Obesity is a central factor in the severity of COVID-19 and related treatment. Behavioral weight loss interventions are an efficacious treatment for obesity, but consistently, Black men and women are minimally represented, and weight loss outcomes are less than clinically significant thresholds. This commentary draws parallels between COVID-19 racial disparities, disparate obesity rates, weight loss treatment outcomes, and underlying systemic racial context. This paper also indicates paths forward to address racialized societal norms in obesity treatment to advance health equity in obesity and reduce acute disease vulnerability. Recommendations for behavioral medicine practice and policy include (1) expanding the research lens to prioritize Black scholars and institutions to generate innovative research questions, (2) creating trustworthy relationships with Black community members to bolster recruitment and retention, (3) employing qualitative methods to facilitate better intervention design and uncover influences of racialized social context, (4) centering Black adults in weight loss interventions, and (5) using multilevel approaches that integrate policy into interventions. Moving forward, this commentary aims to make plain the multilayered form and function of racism, its impact on COVID-19 and obesity, and offer pathways to improve behavioral weight loss interventions that can produce more equitable outcomes.

Impact of training modes on fitness and body composition in women with obesity: A systematic review and meta-analysis

OBJECTIVE

This study aimed to assess the effectiveness of different exercise modalities and determine the optimal exercise prescription for improving cardiorespiratory fitness, body composition, and metabolic health of women with obesity.

METHODS

A systematic review of randomized controlled trials (RCTs) published between January 1988 and October 2020 was conducted. The RCTs were screened using the following inclusion criteria: 1) participants: women aged 18 to 65 years with BMI > 30 kg/m² and without comorbidities; 2) intervention: exercise; 3) comparison: non-intervention control; and 4) outcomes measures: cardiorespiratory fitness (maximal oxygen consumption), body composition (i.e., body weight, percentage body fat), and/or metabolic measures (i.e., blood pressure, cholesterol).

RESULTS

A total of 20 RCTs with a total of 2,062 participants were included. Although the results showed that any form of exercise was more effective than control, improvements in fitness and body composition were modest. Aerobic exercise (vigorous and moderate intensity) appeared most promising for improving fitness and body weight, whereas low-load resistance training resulted in the largest improvements in body fatness.

CONCLUSIONS

In women living with obesity, aerobic exercise was consistently effective in improving fitness and body composition. Although both resistance training and combined exercise interventions appear promising, more research is needed to evaluate their efficacy and determine an optimal exercise prescription for this population.

A randomized feasibility pilot trial of a financial incentives intervention for dietary self-monitoring and weight loss in adults with obesity

Financial incentives could be used to improve adherence to behavioral weight loss interventions, increasing their effectiveness. This Phase IIb randomized pilot study evaluated the feasibility and acceptability of a study protocol for providing financial incentives for dietary self-monitoring and/or weight loss. Community-dwelling adults with obesity were enrolled in a 24 week, group-based weight loss program. Participants were randomized in a 2 × 2 factorial design to receive financial incentives for both dietary self-monitoring and weekly weight loss, just one, or neither. Participants could earn up to $300, evolving from fixed weekly payments to intermittent, variable payments. The notice of reward was provided by text message. The study was conducted in three successive cohorts to evaluate study procedure changes, including dietary approach, recruitment and retention strategies, text messaging, and incentives. Descriptive statistics calculated separately for each cohort described study performance relative to predefined targets for recruitment, including minority representation; retention; adherence; and weight loss. Acceptability was assessed via postintervention qualitative interviews. In Cohort 1 (n = 34), a low-carbohydrate diet was used. Recruitment, retention, adherence, and weight loss were adequate, but minority representation was not. For Cohort 2 (n = 31), employing an additional recruitment method and switching to a reduced-calorie diet yielded adequate recruitment, minority representation, retention, and adherence but less weight loss. Returning to a low-carbohydrate diet in Cohort 3 (n = 28) yielded recruitment, minority representation, retention, adherence, and weight loss similar to Cohort 2. Participant feedback informed changes to text message timing and content and incentive amount. Through successive cohorts, we optimized recruitment and retention strategies and text messaging. An adequately powered trial is warranted to evaluate the efficacy of these incentive structures for reducing weight. The trial registration number is NCT02691260.

Interaction of Neighborhood and Genetic Risk on Waist Circumference in African-American Adults: A Longitudinal Study

BACKGROUND

Understanding determinants of metabolic risk has become a national priority given the increasingly high prevalence rate of this condition among U.S. adults.

PURPOSE

This study's aim was to assess the impact of gene-by-neighborhood social environment interactions on waist circumference (WC) as a primary marker of metabolic risk in underserved African-American adults. Based on a dual-risk model, it was hypothesized that those with the highest genetic risk and who experienced negative neighborhood environment conditions would demonstrate higher WC than those with fewer risk factors.

METHODS

This study utilized a subsample of participants from the Positive Action for Today's Health environmental intervention to improve access and safety for walking in higher-crime neighborhoods, who were willing to provide buccal swab samples for genotyping stress-related genetic pathways. Assessments were conducted with 228 African-American adults at baseline, 12, 18, and 24 months.

RESULTS

Analyses indicated three significant gene-by-environment interactions on WC outcomes within the sympathetic nervous system (SNS) genetic pathway. Two interactions supported the dual-risk hypotheses, including the SNS genetic risk-by-neighborhood social life interaction (b = -0.11, t(618) = -2.02, p = .04), and SNS genetic risk-by-informal social control interaction (b = -0.51, t(618) = -1.95, p = .05) on WC outcomes. These interactions indicated that higher genetic risk and lower social-environmental supports were associated with higher WC. There was also one significant SNS genetic risk-by-neighborhood satisfaction interaction (b = 1.48, t(618) = 2.23, p = .02) on WC that was inconsistent with the dual-risk pattern.

CONCLUSIONS

Findings indicate that neighborhood and genetic factors dually influence metabolic risk and that these relations may be complex and warrant further study.

TRIAL REGISTRATION

NCT01025726.

Fostering spirituality and psychosocial health through mind-body practices in underserved populations

Background

This study examined changes in spirituality and psychosocial outcomes among African American and rural adults participating in a culturally-adapted mind-body intervention.

Methods

African American (n = 22) and rural (n = 38) adults in Harmony & Health attended mind-body sessions twice a week for eight weeks and completed questionnaires on spirituality and psychosocial distress at baseline and post-intervention. Linear regression and repeated measures analyses were used to examine associations between intervention attendance and spirituality.

Results

Attendance was significantly associated with increased spirituality (β=0.168, p = 013). Repeated measures analyses revealed a significant three-way interaction between attendance, spirituality, and study site (F(9,31)=2.891, p = 013). Urban African American participants who attended ≥75% of sessions reported greater increases in spirituality.

Conclusion

Findings suggest that mind-body practices may foster spirituality in urban African American adults. Additional adaptations are needed to strengthen spirituality in rural residents and to improve psychosocial health and wellbeing in this underserved population.

Obesity in early onset breast cancer in African American patients

Obesity is a modifiable risk factor in breast cancer patients and is predictive of disease outcomes in early-onset breast cancer survivors. The purpose of this review is to summarize the current evidence in the association between early-onset breast cancer and obesity, specifically in African-American women. Reviewing the molecular mechanisms and social determinants of disease in this population can provide a foundation for future interventions in prevention, detection, and treatment aiming at improving outcomes for young breast cancer patients.

Similar weight loss and maintenance in African American and White women in the Improving Weight Loss (ImWeL) trial

Objective: African Americans (AA) are often underrepresented and tend to lose less weight than White participants during the intensive phase of behavioral obesity treatment. Some evidence suggests that AA women experience better maintenance of lost weight than White women, however, additional research on the efficacy of extended care programs (i.e. continued contacts to support the maintenance of lost weight) is necessary to better understand these differences.Methods: The influence of race on initial weight loss, the likelihood of achieving ≥5% weight reduction (i.e. extended care eligibility), the maintenance of lost weight and extended care program efficacy was examined in 269 AA and White women (62.1% AA) participating in a 16-month group-based weight management program. Participants achieving ≥5% weight reduction during the intensive phase (16 weekly sessions) were randomized to a clustered campaign extended care program (12 sessions delivered in three, 4-week clusters) or self-directed control.Results: In adjusted models, race was not associated with initial weight loss (p = 0.22) or the likelihood of achieving extended care eligibility (odds ratio 0.64, 95% CI [0.29, 1.38]). AA and White women lost -7.13 ± 0.39 kg and -7.62 ± 0.43 kg, respectively, during initial treatment. There were no significant differences in weight regain between AA and White women (p = 0.64) after adjusting for covariates. Clustered campaign program participants (AA: -6.74 ± 0.99 kg, White: -6.89 ± 1.10 kg) regained less weight than control (AA: -5.15 ± 0.99 kg, White: -4.37 ± 1.04 kg), equating to a 2.12 kg (p = 0.03) between-group difference after covariate adjustments.Conclusions: Weight changes and extended care eligibility were comparable among all participants. The clustered campaign program was efficacious for AA and White women. The high representation and retention of AA participants may have contributed to these findings.

Better Me Within Randomized Trial: Faith-Based Diabetes Prevention Program for Weight Loss in African American Women

PURPOSE

Previous DPP translations in African American women have been suboptimal. This trial evaluated a community-based participatory research developed faith-based diabetes prevention program (DPP) to improve weight loss in African American women.

DESIGN

This cluster randomized trial allocated churches to faith-based (FDPP) or standard (SDPP) DPP interventions. Setting. African American churches. Subjects. Eleven churches with 221 African American women (aged 48.8 ± 11.2 years, BMI = 36.7 ± 8.4) received the FDPP (n = 6) or SDPP (n = 5) intervention.

INTERVENTION

FDPP incorporated 5 faith-based components, including pastor involvement, into the standard DPP curriculum. The SDPP used the standard DPP curriculum. Lay health leaders facilitated interventions at church sites.

MEASURES

Weight and biometrics were collected by blinded staff at baseline, 4- and 10-months.

ANALYSIS

A multilevel hierarchical regression model compared the FDPP and SDPP groups on outcomes.

RESULTS

FDPP and SDPP churches significantly lost weight at 10-months (overall -2.6%, p < .01). Women in FDPP churches who attended at least 15 sessions lost an additional 6.1 pounds at 4-months compared to SDPP corresponding to a 5.8% reduction at 10-months (p < .05). Both groups had significant improvements in health behaviors and biometrics.

CONCLUSIONS

Faith-based and standard DPP interventions led by lay health leaders successfully improved weight, health behaviors, and chronic disease risk. However, the faith-based DPP when fully implemented met the CDC's recommendation for weight loss for diabetes prevention in African American women.

Obesity in African-Americans: The role of physiology

The disproportionate obesity in African American (AA) women has a physiologic basis and can be explained by the interactive effects of insulin secretion, insulin clearance, insulin sensitivity and the glycaemic load of the diet. This review will present data supporting a physiologic basis for obesity propensity in obesity-prone AA women that resides in their unique metabolic/endocrine phenotype: high beta-cell responsiveness, low hepatic insulin extraction and relatively high insulin sensitivity, which together result in a high exposure of tissues and organs to insulin. When combined with a high-glycaemic (HG) diet (that stimulates insulin secretion), this underlying propensity to obesity becomes manifest, as ingested calories are diverted from energy production to storage. Our data indicate that both weight loss and weight loss maintenance are optimized with low-glycaemic (LG) vs HG diet in AA. Whether greater obesity in AA is mechanistically related to their greater prevalence of type 2 diabetes is debatable. This review provides data indicating that obesity is not strongly related to insulin resistance in AA. Rather, insulin resistance in AA is associated with relatively low adipose tissue in the leg, consistent with a genetic predisposition to impaired lipid storage. Greater bioenergetic efficiency has been reported in AA and, via resultant oxidative damage, could plausibly contribute to insulin resistance. In summary, it is proposed here that a subset of AA women are predisposed to obesity due to a specific metabolic/endocrine phenotype. However, greater diabetes risk in AA has an independent aetiology based on impaired lipid storage and mitochondrial efficiency/oxidative stress.

Intermittent Fasting and Metabolic Health: From Religious Fast to Time-Restricted Feeding

Over the past 10 to 15 years, intermittent fasting has emerged as an unconventional approach to reduce body weight and improve metabolic health beyond simple calorie restriction. In this review, we summarize findings related to Ramadan and Sunnah fasting. We then discuss the role of caloric restriction not only as an intervention for weight control, but importantly, as a strategy for healthy aging and longevity. Finally, we review the four most common intermittent fasting (IF) strategies used to date for weight management and to improve cardiometabolic health. Weight loss is common after IF but does not appear to be different than daily caloric restriction when compared directly. IF may also provide additional cardiometabolic benefit, such as insulin sensitization, that is independent from weight loss. While no specific fasting regimen stands out as superior at this time, there is indeed heterogeneity in responses to these different IF diets. This suggests that one dietary regimen may not be ideally suited for every individual. Future studies should consider strategies for tailoring dietary prescriptions, including IF, based on advanced phenotyping and genotyping prior to diet initiation.

Early-phase study of a telephone-based intervention to reduce weight regain among bariatric surgery patients

OBJECTIVE

This study describes early-phase development of a behavioral intervention to reduce weight regain following bariatric surgery. We utilized the Obesity-Related Behavioral Intervention Trials model to guide intervention development and evaluation. We sought to establish recruitment, retention, and fidelity monitoring procedures; evaluate feasibility of utilizing weight from the electronic medical record (EMR) as an outcome; observe improvement in behavioral risk factors; and evaluate treatment acceptability.

METHOD

The intervention comprised 4 weekly telephone calls addressing behavior change strategies for diet, physical activity, and nutrition supplement adherence and 5 biweekly calls addressing weight loss maintenance constructs. Veterans (N = 33) who received bariatric surgery 9-15 months prior consented to a 16-week, pre-post study. Self-reported outcomes were obtained by telephone at baseline and 16 weeks. Clinic weights were obtained from the EMR 6 months pre- and postconsent. Qualitative interviews were conducted at 16 weeks to evaluate treatment acceptability. We aimed to achieve a recruitment rate of ≥ 25% and retention rate of ≥ 80%, and have ≥ 50% of participants regain < 3% of their baseline weight.

RESULTS

Results supported the feasibility of recruiting (48%) and retaining participants (93% provided survey data; 100% had EMR weight). Pre-post changes in weight (73% with < 3% weight regain) and physical activity (Cohen's ds 0.38 to 0.52) supported the potential for the intervention to yield clinically significant results. Intervention adherence (mean 7.8 calls of 9 received) and positive feedback from interviews supported treatment acceptability.

CONCLUSIONS

The intervention should be evaluated in an adequately powered randomized controlled trial. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Comparative effectiveness of a standard behavioral and physical activity enhanced behavioral weight loss intervention in Black women

Black women typically lose small amounts of weight in behavioral weight loss interventions, partially due to low engagement in physical activity. Culturally relevant enhancement of the physical activity component may improve weight loss. This study compared the effectiveness of a culturally-relevant, physical activity-enhanced behavioral weight loss intervention to a standard behavioral weight loss intervention in Black women (n = 85) over 6 months. The study was conducted in two cohorts from March 2016 to February 2017 at the University of North Carolina at Chapel Hill. Participants had an average age of 48.30 ± 11.02 years with an average body mass index of 36.46 ± 4.50 kg/m². Standard and enhanced groups' weight change (-2.83 kg and -2.08 kg, respectively) and change in physical activity (43.93 min/ week and 15.29 min/week, respectively) did not differ between groups. Significantly more standard group participants lost 5% of baseline weight compared to enhanced group participants. This study produced typical weight loss results in Black women. Behavioral weight loss treatment remains moderately effective for Black women. Strategies to increase attendance and self-monitoring, and the inclusion of cultural contexts to weight-related behaviors are needed to improve outcomes.

Baseline motives for eating palatable food: racial differences and preliminary utility in predicting weight loss

PURPOSE

Behavioral predictors of weight-loss program (WLP) outcomes are needed and important because they can be modified. Eating calorie-dense palatable foods (PFs) outside of hunger contributes to obesity. This study assessed if habitual motives to consume PFs could predict weight-loss outcomes.

METHODS

N = 171 Black and N = 141 White adults in a reduced-calorie program completed the Palatable Eating Motives Scale (PEMS). Body weight and body mass index (BMI) lost after 3 and 6 months were analyzed controlling for initial BMI and demographics. Greater PEMS motive scores meant more frequent habitual intake of PFs for that motive.

RESULTS

Whites vs. Blacks had higher scores on most of the PEMS motives: Social, Coping, and Reward Enhancement. In Whites at 3 months, greater Reward Enhancement scores and initial BMI predicted more BMI loss (p < 0.05). At 6 months, greater Reward Enhancement and lower Conformity scores predicted more weight (p < 0.05) and BMI loss (Conformity: p < 0.05; Reward Enhancement: p = 0.05). PEMS motives did not predict outcomes for Blacks.

CONCLUSION

The results provide preliminary evidence for the PEMS to predict WLP outcomes. White patients who eat PFs primarily for their rewarding properties and less to conform should fare better in Lifestyle programs while group or family-based interventions may be more efficacious when conformity is the main motive. Lower motive scores among Blacks suggest that eating PFs outside of hunger may go unrecognized or underreported and warrants further investigation. The findings highlight the motive-based heterogeneity of obesity and how it may be used to predict outcomes and customize interventions to improve WLP outcomes.

LEVEL OF EVIDENCE

Level IV, multiple time series.

Impact of a structured lifestyle programme on patients with metabolic syndrome complicated by non-alcoholic fatty liver disease

BACKGROUND

Lifestyle interventions are first-line therapy for non-alcoholic fatty liver disease (NAFLD).

AIMS

To examine the prevalence of NAFLD among participants of the University of Michigan Metabolic Fitness (MetFit) Programme and to assess the impact of this programme on weight, metabolic and liver-related parameters among patients with and without NAFLD.

METHODS

Adults who completed the programme between 2008 and 2016 were included. Clinical and laboratory data were collected at enrolment, and at 12 and 24 weeks. NAFLD was defined based on liver biopsy, imaging or clinical diagnosis.

RESULTS

The cohort (N = 403; 253 12-week, 150 24-week) consisted primarily of middle-aged (median 54 years) white (88%) men (63%) with severe obesity (median BMI 37.4). 47.6% met criteria for NAFLD. At baseline, NAFLD patients were younger (52 vs 55 years), had higher weights and more metabolic derangements (higher fasting insulin and triglyceride, lower high-density lipoprotein-cholesterol). At programme completion, 30% achieved weight reduction ≥5%, 62% resolution of hypertriglyceridaemia, 33% resolution of low HDL, 27% resolution of impaired fasting glucose and 43% normalisation of alanine aminotransferase. Endpoints were unaffected by NAFLD. Longer programme duration (OR 6.7, 95% CI 3.6-12.3) and white race (OR 3.83, 95% CI 1.04-1.76) were independent predictors of ≥5% weight loss.

CONCLUSIONS

Nearly half of the patients referred to a structured lifestyle programme for metabolic syndrome had NAFLD. Although baseline metabolic derangements were more pronounced among NAFLD patients, the programme was equally efficacious in achieving weight loss and resolving metabolic syndrome components. Programme duration was the most important predictor of response.

A Church-Based Weight Loss Intervention in African American Adults using Text Messages (LEAN Study): Cluster Randomized Controlled Trial

Background

African American adults experience a high prevalence of obesity and its associated comorbidities, including diabetes. Church-based interventions have been shown to be effective in decreasing weight in this population. mHealth interventions can address two needs for obesity treatment in this community, including enhancing weight loss and providing wide dissemination.

Objective

This study aimed to assess the feasibility and efficacy of a church-based weight loss intervention that incorporates mHealth technology.

Methods

In this study, 8 churches (n=97) were randomly assigned to the intervention or delayed intervention condition (control group). We recruited participants through their respective church. Volunteer church members were trained by study staff to deliver the 10-session, 6-month intervention. Participants in the intervention group attended group sessions and received automated short message service (SMS) text messages designed to reinforce behavioral strategies. Conversely, participants in the delayed intervention condition received SMS text messages related to health conditions relevant for African American adults. We obtained measures of body composition, blood pressure, blood glucose, and cholesterol.

Results

We successfully recruited 97 African American adults, with a mean age of 56.0 (SE 10.3) years and a mean body mass index of 38.6 (SE 6.4) kg/m2 (89/97, 91.8% females), who attended the churches that were randomized to the intervention (n=68) or control (n=29) condition. Of these, 74.2% (72/97) of the participants (47/68, 69.1% intervention; 25/29, 86.2% delayed intervention) completed the 6-month assessment. The average intervention group attendance was 55%. There was a significant difference in weight loss (P=.04) between participants in the intervention (–1.5 (SE 0.5) kg) and control (0.11 (SE 0.6) kg) groups. Among participants in the intervention group, the correlation between the number of SMS text messages sent and the percent body fat loss was r=.3 with P=.04. The participants reported high satisfaction with the automated SMS text messages.

Conclusions

Automated SMS text messages were well-received by participants, suggesting that more enhanced mHealth technologies are a viable option for interventions targeting African American adults.

Trial Registration

ClinicalTrials.gov NCT02863887; https://clinicaltrials.gov/ct2/show/NCT02863887 (Archived by WebCite at http://www.webcitation.org/71JiYzizO)

Lower depression scores associated with greater weight loss among rural black women in a behavioral weight loss program

Depression and stress have been associated with less weight loss among some participants in behavioral weight loss (BWL) programs. The purpose of this study was to (1) measure the levels of depression and stress among a sample of black women living in rural Alabama and Mississippi who were participating in a BWL program and (2) examine the association between these psychosocial variables and weight loss outcomes of participants at 6 months. Overweight and obese black women in a BWL program (n = 409) completed validated surveys to measure depression and stress at baseline and 6 months. Weight and height were also measured at baseline and 6 months. Statistical tests were conducted to examine associations between depression, stress, and weight loss. Mean BMI at baseline was 38.68 kg/m². Participants achieved a 1.17 kg/m² reduction in BMI at 6 months. When comparing by baseline depression or stress categories, no significant differences in weight loss outcomes were observed. Analysis of continuous data revealed a significant correlation between baseline depression score and change in BMI. In adjusted models, change in depression score over time was significantly associated with change in weight. No differences in weight loss outcomes at 6 months were observed when comparing participants with and without elevated depressive symptoms or elevated stress at baseline. This suggests that potential participants may not need to be excluded from BWL programs based on pre-specified cut points for these psychological conditions. Greater improvements in depression were associated with better weight loss outcomes suggesting that more emphasis on reducing depression may lead to greater weight losses for black women in BWL programs.

Racial Differences in Weight Loss Mediated by Engagement and Behavior Change

Objective

We set out to determine if a primarily Internet-delivered behavioral weight loss intervention produced differential weight loss in African American and non-Hispanic White women, and to identify possible mediators.

Design

Data for this analysis were from a randomized controlled trial, collected at baseline and 4-months.

Setting

The intervention included monthly face-to-face group sessions and an Internet component that participants were recommended to use at least once weekly.

Participants

We included overweight or obese African American and non-Hispanic White women (n=170), with at least weekly Internet access, who were able to attend group sessions.

Intervention

Monthly face-to-face group sessions were delivered in large or small groups. The Internet component included automated tailored feedback, self-monitoring tools, written lessons, video resources, problem solving, exercise action planning tools, and social support through message boards.

Main Outcome Measure

Multiple linear regression was used to evaluate race group differences in weight change.

Results

Non-Hispanic White women lost more weight than African American women (-5.03% vs.-2.39%, P=.0002). Greater website log-ins and higher change in Eating Behavior Inventory score in non-Hispanic White women partially mediated the race-weight loss relationship.

Conclusions

The weight loss disparity may be addressed through improved website engagement and adoption of weight control behaviors.

Young Adults' Attitudes and Perceptions of Obesity and Weight Management: Implications for Treatment Development

Young adults are underrepresented in standard behavioral weight loss trials, and evidence suggests that they differ from older adults on many weight-related constructs. The aim of this review is to explore young adults' attitudes toward obesity and weight management, with particular attention to those factors that may play a role in the development of future treatment efforts. Both intrapersonal and interpersonal considerations unique to young adulthood are assessed; in addition, we examine young adults' perceptions of specific weight-related behaviors such as dieting, physical activity, and self-weighing. Conclusions are consistent with other findings suggesting that weight management interventions should be adapted and designed specifically for this age group.

Weight Outcomes of Latino Adults and Children Participating in the Y Living Program, a Family-Focused Lifestyle Intervention, San Antonio, 2012-2013

Introduction

US Latinos have disproportionately higher rates of obesity and physical inactivity than the general US population, putting them at greater risk for chronic disease. This evaluation aimed to examine the impact of the Y Living Program (Y Living), a 12-week family-focused healthy lifestyle program, on the weight status of adult and child (aged ≥7 years) participants.

Methods

In this pretest–posttest evaluation, participants attended twice-weekly group education sessions and engaged in physical activity at least 3 times per week. Primary outcome measures were body mass index ([BMI], zBMI and BMI percentile for children), weight, waist circumference, and percentage body fat. Wilcoxon signed-rank tests and mixed effects models were used to evaluate pretest–posttest differences (ie, absolute change and relative change) for adults and children separately.

Results

BMI, weight, waist circumference, and percentage body fat improved significantly (both absolutely and relatively) among adults who completed the program (n = 180; all P ≤ .001). Conversely, child participants that completed the program (n = 72) showed no improvements. Intervention effects varied across subgroups. Among adults, women and participants who were obese at baseline had larger improvements than did children who were obese at baseline or who were in families that had an annual household income of $15,000 or more.

Conclusion

Significant improvements in weight were observed among adult participants but not children. This family-focused intervention has potential to prevent excess weight gain among high-risk Latino families.