Outcomes from Partner2Lose: a randomized controlled trial to evaluate 24-month weight loss in a partner-assisted intervention.

BACKGROUND: Partner support is associated with better weight loss outcomes in observational studies, but randomized trials show mixed results for including partners. Unclear is whether teaching communication skills to couples will improve weight loss in a person attempting weight loss (index participant). PURPOSE: To compare the efficacy of a partner-assisted intervention versus participant-only weight management program on 24-month weight loss. METHODS: This community-based study took place in Madison, WI. Index participants were eligible if they met obesity guideline criteria to receive weight loss counseling, were aged 18-74 years, lived with a partner, and had no medical contraindications to weight loss; partners were aged 18-74 years and not underweight. Couples were randomized 1:1 to a partner-assisted or participant-only intervention. Index participants in both arms received an evidence-based weight management program. In the partner-assisted arm, partners attended half of the intervention sessions, and couples were trained in communication skills. The primary outcome was index participant weight at 24 months, assessed by masked personnel; secondary outcomes were 24-month self-reported caloric intake and average daily steps assessed by an activity tracker. General linear mixed models were used to compare group differences in these outcomes following intent-to-treat principles. RESULTS: Among couples assigned to partner-assisted (n = 115) or participant-only intervention (n = 116), most index participants identified as female (67%) and non-Hispanic White (87%). Average baseline age was 47.27 years (SD 11.51 years) and weight was 106.55 kg (SD 19.41 kg). The estimated mean 24-month weight loss was similar in the partner-assisted (2.66 kg) and participant-only arms (2.89 kg) (estimated mean difference, 0.23 kg [95% CI, -1.58, 2.04 kg], p=0.80). There were no differences in 24-month average daily caloric intake (estimated mean difference 50 cal [95% CI: -233, 132 cal], p=0.59) or steps (estimated mean difference 806 steps [95% CI: -1675, 64 steps], p=0.07). The percentage of participants reporting an adverse event with at least possible attribution to the intervention did not differ by arm (partner-assisted: 9%, participant-only, 3%, p = 0.11). CONCLUSIONS: Partner-assisted and individual weight management interventions led to similar outcomes in index participants. TRIAL REGISTRATION: Clinicaltrials.gov NCT03801174, January 11, 2019.

A non-randomized comparison of engagement and outcomes for in-person versus virtual delivery of the Partner2Lose weight management trial.

Objective: Existing behavioral weight management interventions produce clinically meaningful weight loss. The onset of the COVID-19 pandemic led to the quick transition of such interventions from in-person to virtual platforms. This provided a unique opportunity to compare engagement and outcomes for an in-person versus virtually delivered weight management intervention. Methods: A non-randomized comparison of engagement and weight outcomes was performed between two cohorts who participated in a weight management intervention in person (N = 97) versus three who participated virtually via videoconference (N = 134). Various metrics of engagement were examined, including group class and individual phone call attendance and duration, and retention for weight assessments. Behavioral targets of daily caloric intake and step-counts and the clinical weight outcome were explored. Results: Cohorts (mean [standard deviation] age 47.3 (11.5), 67.1% women: 86.8% White) that participated virtually attended more group sessions (p < 0.001) and had maintenance telephone calls that were of a longer duration (p < 0.001). No other engagement or weight outcomes significantly differed by delivery modality. Conclusions: Virtual weight management programs are promising and may generate similar outcomes to those delivered in-person. Future research should seek to understand how best to promote and sustain engagement in virtual interventions.

Metaproteomics and DNA metabarcoding as tools to assess dietary intake in humans.

Objective biomarkers of food intake are a sought-after goal in nutrition research. Most biomarker development to date has focused on metabolites detected in blood, urine, skin or hair, but detection of consumed foods in stool has also been shown to be possible via DNA sequencing. An additional food macromolecule in stool that harbors sequence information is protein. However, the use of protein as an intake biomarker has only been explored to a very limited extent. Here, we evaluate and compare measurement of residual food-derived DNA and protein in stool as potential biomarkers of intake. We performed a pilot study of DNA sequencing-based metabarcoding (FoodSeq) and mass spectrometry-based metaproteomics in five individuals' stool sampled in short, longitudinal bursts accompanied by detailed diet records (n=27 total samples). Dietary data provided by stool DNA, stool protein, and written diet record independently identified a strong within-person dietary signature, identified similar food taxa, and had significantly similar global structure in two of the three pairwise comparisons between measurement techniques (DNA-to-protein and DNA-to-diet record). Metaproteomics identified proteins including myosin, ovalbumin, and beta-lactoglobulin that differentiated food tissue types like beef from dairy and chicken from egg, distinctions that were not possible by DNA alone. Overall, our results lay the groundwork for development of targeted metaproteomic assays for dietary assessment and demonstrate that diverse molecular components of food can be leveraged to study food intake using stool samples.

Primary outcomes from Partner2Lose: A randomized controlled trial to evaluate partner involvement on long-term weight loss.

Background: Partner support is associated with better weight loss outcomes in observational studies, but randomized trials show mixed results for including partners. Unclear is whether teaching communication skills to couples will improve weight loss in index participants. Purpose: To compare the efficacy of a partner-assisted intervention versus participant-only weight management program on long-term weight loss. Methods: This community-based study took place in Madison, WI. Index participants were eligible if they met obesity guideline criteria to receive weight loss counseling, were aged 74 years or younger, lived with a partner, and had no medical contraindications to weight loss; partners were aged 74 years or younger and not underweight. Couples were randomized 1:1 to a partner-assisted or participant-only intervention. Index participants in both arms received an evidence-based weight management program. In the partner-assisted arm, partners attended half of the intervention sessions, and couples were trained in communication skills. The primary outcome was index participant weight at 24 months, assessed by masked personnel; secondary outcomes were 24-month self-reported caloric intake and average daily steps assessed by an activity tracker. General linear mixed models were used to compare group differences in these outcomes following intent-to-treat principles. Results: Among couples assigned to partner-assisted (n=115) or participant-only intervention (n=116), most index participants identified as female (67%) and non-Hispanic White (87%). Average baseline age was 47.27 years (SD 11.51 years) and weight was 106.55 kg (SD 19.41 kg). The estimated mean 24-month weight loss was similar in the partner-assisted (2.66 kg) and participant-only arms (2.89 kg) (estimated mean difference, 0.23 kg [95% CI, -1.58, 2.04 kg]). There were no differences in 24-month average daily caloric intake (50 cal [95% CI: -233, 132 cal]) or steps (806 steps [95% CI: -1675, 64 steps]). The percentage of participants reporting an adverse event with at least possible attribution to the intervention did not differ by arm (partner-assisted: 9%, participant-only, 3%, p=0.11). Conclusions: Partner-assisted and individual weight management interventions led to similar outcomes in index participants. Trial registration: Clinicaltrials.gov NCT03801174.

Expert consensus on nutrition and lower-carbohydrate diets: An evidence- and equity-based approach to dietary guidance.

There is a substantial body of clinical evidence supporting the beneficial effects of lower-carbohydrate dietary patterns on multiple established risk factors associated with insulin resistance and cardiovascular diseases in adult populations. Nutrition and health researchers, clinical practitioners, and stakeholders gathered for, "The Scientific Forum on Nutrition, Wellness, and Lower-Carbohydrate Diets: An Evidence- and Equity-Based Approach to Dietary Guidance" to discuss the evidence base around lower-carbohydrate diets, health outcomes, and dietary guidance. Consensus statements were agreed upon to identify current areas of scientific agreement and spotlight gaps in research, education, and practice to help define and prioritize future pathways. Given the evidence base and considering that most American adults are living with at least one nutrition-related chronic disease, there was consensus that including a lower-carbohydrate dietary pattern as one part of the Dietary Guidelines for Americans could help promote health equity among the general population.