log2lose: incenting weight loss and dietary self-monitoring in real-time to improve weight management among adults with obesity

Conditions: Obesity

Summary: this study involves an evaluation of whether providing small incentives weekly for dietary self-monitoring and/or weight loss improves short- and long-term weight loss. participants can expect to be on study for 18 months.

in this two-site, randomized, single-masked, longitudinal 2x2 factorial study, called log2lose, adults with obesity from madison, wi and durham, nc will be offered a 78 week, evidence-based behavioral weight management program comprising an incentivized weight loss intervention for 26 weeks (phase i), an incentivized weight loss maintenance intervention for 26 weeks (phase ii), and a non-incentivized weight maintenance intervention for 26 weeks (phase iii). participants will be randomized in a 2x2 design to receive adjunctive incentives for either weekly weight loss or dietary self-monitoring, both, or neither. the investigators will assess the proportion of participants achieving clinically significant weight loss of greater than or equal to 5 percent at the end of each phase. all participants will participate in an 18-month weight management program delivered via videoconference.

Eligibility criteria:
inclusion criteria: * bmi ≥30 kg/m2 * desire to lose weight * agrees to attend outcome visits per protocol * available for class times * transportation and ability to attend in-person study visits at baseline (screening), 26, 52, and 78 weeks * able to stand for weight measurements without assistance * able to speak and read english * able to download and use the myfitnesspal and fitbit apps daily * possess smart phone with data and texting plan * have or willing to create a gmail address * able to connect to a video conference call using a smartphone, tablet or computer with a webcam and microphone * score of at least 4 out of 6 on a validated cognitive screener exclusion criteria: * weight \>380 lb * weight loss of at least 10 lbs in the month prior to screening * currently enrolled or enrolled in previous month in a clinical, research, or community program focusing on lifestyle change that could affect weight * current use of weight loss medication * history of bariatric surgery or planning to have bariatric surgery in the study timeframe * residing in a nursing home or receiving home health care * impaired hearing * significant dementia, drug or alcohol misuse, or unstable psychiatric illness (e.g., schizophrenia, psychosis) * current treatment for cancer or being treated for cancer (besides basal cell carcinoma or squamous cell) in the last 6 months * use of insulin, sulfonylureas, or meglitinides due to increased risk for hypoglycemia * pregnant, breastfeeding, or planning to become pregnant within the study timeframe * diuretic medication doses higher than hydrochlorothiazide 25 mg daily, furosemide 40 mg daily, torsemide 20 mg daily, bumetanide 1 mg daily, or any use of metolazone; use of potassium-sparing diuretics is acceptable * chronic kidney disease at stage 4 or 5 * unstable heart disease in the 6 months prior to screening * exertional chest pain * history of ascites requiring paracentesis * pain, fainting or other conditions that prohibit mild/moderate exercise