Randomized controlled trial of a comprehensive home environment-focused weight-loss program for adults.

Behavioral weight loss programs (BWL) provide limited instruction on how to change the environmental context of weight-regulating behaviors, perhaps contributing to regain. Drawing on social ecological models, this trial evaluated a comprehensive weight loss program that targeted both an individual’s behavior and their physical and social home environment

Recruitment of young adults into a randomized controlled trial of weight gain prevention: message development, methods, and cost

Abstract Background Young adulthood (age 18 to 35) is a high-risk period for unhealthy weight gain. Few studies have recruited for prevention of weight gain, particularly in young adults. This paper describes the recruitment protocol used in the Study of Novel Approaches to Prevention (SNAP). Methods We conducted extensive formative work to inform recruitment methods and message development. We worked with a professional marketing firm to synthesize major themes and subsequently develop age-appropriate messages for recruitment. A variety of approaches and channels were used across two clinical centers to recruit young adults who were normal or overweight (body mass index (BMI) 21 to 30 kg/m2) for a 3-year intervention designed to prevent weight gain. We tracked recruitment methods, yields, and costs by method. Logistic regression was used to identify recruitment methods that had the highest relative yield for subgroups of interest with covariate adjustments for clinic. Results The final sample of 599 participants (27% minority, 22% male) was recruited over a 19-month period of sustained efforts. About 10% of those who initially expressed interest via a screening website were randomized. The most common reason for ineligibility was already being obese (BMI >30 kg/m2). The top two methods for recruitment were mass mailing followed by email; together they were cited by 62% of those recruited. Television, radio, paid print advertising, flyers and community events each yielded fewer than 10% of study participants. Email was the most cost-effective method per study participant recruited. Conclusions These findings can guide future efforts to recruit young adults and for trials targeting weight gain prevention. Trial registration ClinicalTrials.gov NCT01183689 (registered 13 August 2010)

Weight gain prevention in young adults: design of the study of novel approaches to weight gain prevention (SNAP) randomized controlled trial

Abstract: Background Weight gain during young adulthood is common and is associated with increased cardiovascular risk. Preventing this weight gain from occurring may be critical to improving long-term health. Few studies have focused on weight gain prevention, and these studies have had limited success. SNAP (Study of Novel Approaches to Weight Gain Prevention) is an NIH-funded randomized clinical trial examining the efficacy of two novel self-regulation approaches to weight gain prevention in young adults compared to a minimal treatment control. The interventions focus on either small, consistent changes in eating and exercise behaviors, or larger, periodic changes to buffer against expected weight gains. Methods/Design SNAP targets recruitment of six hundred young adults (18–35 years) with a body mass index between 21.0-30.0 kg/m2, who will be randomly assigned with equal probability to: (1) minimal intervention control; (2) self-regulation with Small Changes; or (3) self-regulation with Large Changes. Both interventions receive 8 weekly face-to-face group sessions, followed by 2 monthly sessions, with two 4-week refresher courses in each of subsequent years. Participants are instructed to report weight via web at least monthly thereafter, and receive monthly email feedback. Participants in Small Changes are taught to make small daily changes (~100 calorie changes) in how much or what they eat and to accumulate 2000 additional steps per day. Participants in Large Changes are taught to create a weight loss buffer of 5–10 pounds once per year to protect against anticipated weight gains. Both groups are encouraged to self-weigh daily and taught a self-regulation color zone system that specifies action depending on weight gain prevention success. Individualized treatment contact is offered to participants who report weight gains. Participants are assessed at baseline, 4 months, and then annually. The primary outcome is weight gain over an average of 3 years of follow-up; secondary outcomes include diet and physical activity behaviors, psychosocial measures, and cardiovascular disease risk factors. Discussion SNAP is unique in its focus on weight gain prevention in young adulthood. The trial will provide important information about whether either or both of these novel interventions are effective in preventing weight gain. Trial registration ClinicalTrials.gov, NCT0118368

Dietary outcomes within the study of novel approaches to weight gain prevention (SNAP) randomized controlled trial

Abstract Background Young adults (YA) are at high-risk for unhealthy dietary behaviors and weight gain. The Study of Novel Approaches to Weight Gain Prevention (SNAP) Trial demonstrated that two self-regulation approaches were effective in reducing weight gain over 2 years compared with control. The goal of this analysis was to examine effects of intervention on dietary outcomes and the association of diet changes with weight change. Methods Participants were 599 YA, age 18–35 years, BMI 21.0–30.0 kg/m2 (27.4 ± 4.4 years; 25.4 ± 2.6 kg/m2; 22% men; 73% non-Hispanic White), who were recruited in Providence, RI and Chapel Hill, NC and randomized to self-regulation with Small Changes (SC), self-regulation with Large Changes (LC) or Control (C). SC and LC emphasized frequent self-weighing to cue behavior changes (small daily changes vs. periodic large changes) and targeted high-risk dietary behaviors. Diet and weight were assessed at baseline, 4 months and 2 years. Results LC and SC had greater decreases in energy intake than C at 4 months but not 2 years. LC had the greatest changes in percent calories from fat at 4 months, but differences were attenuated at 2 years. No differences in diet quality were observed. Across conditions, increased total energy consumption, fast food, meals away from home, and binge drinking, and decreased dietary quality and breakfast consumption were all associated with weight gain at 2 years. Conclusions This study suggests the need to strengthen interventions to produce longer term changes in dietary intake and helps to identify specific behaviors associated with weight gain over time in young adults. Trial registration Clinicaltrials.gov # NCT01183689 , registered August 18, 2010

Extreme Hinge Axis Positions Are Necessary to Achieve Posterior Tibial Slope Reduction With Small Coronal-Plane Corrections in Medial Opening Wedge High Tibial Osteotomy

Background: Both coronal- and sagittal-plane knee malalignment can increase the risk of ligamentous injuries and the progression of degenerative joint disease. High tibial osteotomy can achieve multiplanar correction, but determining the precise hinge axis position for osteotomy is technically challenging. Purpose: To create computed tomography (CT)–based patient-specific models to identify the ideal hinge axis position angle and the amount of maximum opening in medial opening wedge high tibial osteotomy (MOWHTO) required to achieve the desired multiplanar correction. Study Design: Descriptive laboratory study. Methods: A total of 10 patients with lower extremity CT scans were included. Baseline measurements including the mechanical tibiofemoral angle (mTFA) and the posterior tibial slope (PTS) were calculated. Virtual osteotomy was performed to achieve (1) a specified degree of PTS correction and (2) a planned degree of mTFA correction. The mean hinge axis position angle for MOWHTO to maintain an anatomic PTS (no slope correction) was 102.6° ± 8.3° relative to the posterior condylar axis (PCA). Using this as the baseline correction, the resultant hinge axis position and maximum opening were then calculated for each subsequent osteotomy procedure. Results: For 5.0° of mTFA correction, the hinge axis position was decreased by 6.8°, and the maximum opening was increased by 0.49 mm for every 1° of PTS correction. For 10.0° of mTFA correction, the hinge axis position was decreased by 5.2°, and the maximum opening was increased by 0.37 mm for every 1° of PTS correction. There was a significant difference in the trend-line slopes for hinge axis position versus PTS correction ( P = .013) and a significant difference in the trend-line intercepts for maximum opening versus PTS correction ( P &lt; .0001). Conclusion: The mean hinge axis position for slope-neutral osteotomy was 102.6° ± 8.3° relative to the PCA. For smaller corrections in the coronal plane, more extreme hinge axis positions were necessary to achieve higher magnitudes of PTS reduction. Clinical Relevance: Extreme hinge axis positions are technically challenging and can lead to unstable osteotomy. Patient-specific instrumentation may allow for precise correction to be more readily achieved. </jats:sec

Randomized controlled trial of a comprehensive home environment-focused weight-loss program for adults.

OBJECTIVE: Behavioral weight loss programs (BWL) provide limited instruction on how to change the environmental context of weight-regulating behaviors, perhaps contributing to regain. Drawing on social ecological models, this trial evaluated a comprehensive weight loss program that targeted both an individual’s behavior and their physical and social home environment. METHODS: Overweight and obese adults (N=201; 48.9±10.5 years; 78.1% women) were randomized to BWL or to BWL plus home environment changes (BWL+H). Groups met weekly for 6 months and bi-monthly for 12 months. BWL+H participants were given items to facilitate healthy choices in their homes (e.g., exercise equipment, portion plates) and attended treatment with a household partner. Weight loss at 6 and 18 months was the primary outcome. RESULTS: BWL+H changed many aspects of the home environment and produced better 6 month weight losses than BWL (p=.017). At 18 months, no weight loss differences were observed (p=.19) and rates of regain were equivalent (p=.30). Treatment response was moderated by gender (6 month p=.01; 18 month p=.006). Women lost more weight in BWL+H than BWL at 6 and 18 months, whereas men in BWL lost more weight than those in BWL+H at 18 months. Partners, regardless of gender, lost more weight in BWL+H than BWL at both time points (ps<.0001). CONCLUSION: The home food and exercise environment is malleable and targeting this microenvironment appears to improve initial weight loss, and in women, 18-month outcomes. Research is needed to understand this gender difference and to develop home-focused strategies with more powerful and sustained weight loss effects

Real-time monitoring of the deactivation of HZSM-5 during upgrading of pine pyrolysis vapors

The conversion of pine pyrolysis vapors over fixed beds of HZSM-5 catalyst was studied as a function of deactivation of the catalyst, presumably by coking.</p