IIR 11-040
Maintenance After Initiation of Nutrition TrAINing (MAINTAIN)
Corrine I. Voils, PhD Durham VA Medical Center, Durham, NC Durham, NC William Yancy MD MHS Durham VA Medical Center, Durham, NC Durham, NC Funding Period: May 2012 - October 2015 Portfolio Assignment: Care of Complex Chronic Conditions |
BACKGROUND/RATIONALE:
Obesity is the second leading cause of preventable deaths in the United States and is associated with a wide range of diseases. Most patients who achieve weight loss regain much of this weight within a year. The MAINTAIN intervention was developed to slow the rate of weight regain following weight loss. OBJECTIVE(S): The current study examined the effectiveness of a weight loss maintenance program following initial weight loss among obese veterans. Specific Aims were to: Aim 1: Compare mean net weight loss in the maintenance group with the usual care group at the end of the study period. Aim 2: Compare the mean improvement in caloric intake in the maintenance group versus the usual care group at the end of the study period. Aim 3: Compare the mean improvement in physical activity in the maintenance group with the usual care group at the end of the study period. Aim 4: Examine the cost effectiveness of the maintenance intervention compared to usual care. METHODS: Veterans aged 75 years or less with a body mass index of 30 kg/m2 or higher participated in a 16-week group-based weight loss program. Participants who lost at least 4 kg were randomized to receive (a) usual care for 56 weeks or (b) maintenance intervention for 42 weeks, followed by 14 weeks of no intervention contact. The maintenance intervention involved three in-person group visits and transitioned to individualized telephone calls. Weights were multiply imputed using Markov chain Monte Carlo under a general multivariate normal model. Then, a longitudinal data model including weights at week 0 and week 56 was fit; predictors included the week 56 time indicator, treatment arm by time interaction, and the stratification variable of amount of weight change during the 16-week weight loss phase. Linear mixed models (LMMs) were used to analyze caloric intake with time indicators for weeks 26 and 56, the treatment arm by time interaction, and the stratification variable. Generalized LMMs were fit using a negative binomial distribution and log link function to examine minutes of physical activity per week; independent variables were identical to those included in the caloric intake model. FINDINGS/RESULTS: Telephone screen attempts were made for 1130 patients, of which 685 were scheduled for in-person consent and screening. Of the 504 participants who provided a weight for the first initiation group session, 148 were lost to follow-up, 52 withdrew, 82 failed to lose at least 4 kg, and 222 lost at least 4 kg and were randomized (110 maintenance intervention, 112 usual care). Retention was 80% for the maintenance intervention and 90% for usual care. Attendance at the three maintenance group meetings ranged from 0-3, mean(M)=2.07, standard deviation (SD)=1.06. Participation in the eight maintenance telephone calls ranged from 2-8, M=7.34, SD=1.43. Retention for 56-week assessments in the usual care and maintenance arms were 90% and 80% for weight, 78% and 76% for FFQ, and 89% and 79% for IPAQ. The maintenance group only regained 0.74 kg during the 56-week intervention period, whereas the usual care group regained 2.36 kg. This treatment difference was statistically significant (estimated mean: -1.61 (95% confidence interval (CI): 0.07, 3.13, p=.04). A statistically significant difference in self-reported energy intake (kcal) was noted between the maintenance (estimated mean 1176.06) and usual care (estimated mean 1399.50) groups at week 26 (estimated mean difference -223.44; 95% CI: -395.92, -50.96; p=0.01). However, the between-group difference was no longer statistically significant at 56 weeks (estimated means: maintenance, 1226.84; usual care, 1352.34; estimated mean difference: -125.49; 95% CI: -280.71, 29.72; p=0.11). There were no differences in estimated rates of walking or moderate physical activity among the maintenance group relative to the usual care group at week 26 (walking IRR: 1.38; 95% CI: 0.85, 2.23; p=0.19; moderate IRR: 1.01; 95% CI: 0.54, 1.90; p=0.96) or week 56 (walking IRR: 1.03; 95% CI: 0.63, 1.68; p=0.91; moderate IRR: 1.07; 95% CI: 0.57, 2.03; p=0.83). Aggregate labor and capital costs for delivering the intervention were generated from activity logs of interventionists and market rates for capital costs. Labor costs were calculated as the product of the time reported on the activity logs and hourly wage derived from interventionist salaries from the General Schedule salary table for Durham. Intervention cost was $88.58 per participant for the group-based initiation intervention and $276.19 per participant for the individual maintenance intervention. There were no differences in mean and median VA total expenditures by group during the 56 week maintenance phase [(maintenance group mean $11,932 (SD=$20,714), usual care mean $14,876 (SD=$32,795), p=0.42; maintenance group median $4,292 (IQR=$13,429), usual care median $5,584 (IQR=$11,438), p=0.37]. IMPACT: The next step in this program of research is to refine the intervention to help patients maintain weight loss following weight loss surgery. Ultimately, sustained weight loss could reduce obesity-related health care utilization and costs. External Links for this ProjectNIH ReporterGrant Number: I01HX000690-01Link: https://reporter.nih.gov/project-details/8199683 Dimensions for VADimensions for VA is a web-based tool available to VA staff that enables detailed searches of published research and research projects.Learn more about Dimensions for VA. VA staff not currently on the VA network can access Dimensions by registering for an account using their VA email address. Search Dimensions for this project PUBLICATIONS:Journal Articles
DRA:
Health Systems Science, Other Conditions
DRE: Treatment - Efficacy/Effectiveness Clinical Trial, Treatment - Comparative Effectiveness Keywords: none MeSH Terms: none |