Obesity, Morbid
Conditions
Keywords
weight reduction programs, diet, Caloric restriction, weight loss, weight gain
Brief summary
Very-low calorie diets are relatively safe and effective in inducing significant weight loss, when used in selective individuals and under clinical supervision. However, weight loss maintenance in the long-term remains the main challenge, with many experiencing a significant weight regain. Several compensatory mechanisms are activated under weight reduction, both at the level of energy intake (such as increased appetite) and energy expenditure (such as reduced energy expenditure), and increase the risk of relapse. The main aim of this study is to compare the effect of two multidisciplinary lifestyle interventions on weight loss maintenance at one year, after initial weight loss during 8 weeks very-low calorie diet. Participants will be allocated (non-randomly) to either an outpatient program in the obesity unit of the local hospital, or to an inpatient program consisting of a continuous care intervention, with three intermittent stays (each with three-week duration) in a rehabilitation center over a one year period. Moreover, the investigators aim to assess the impact of weight loss (achieved with a very low calorie diet) and weight loss maintenance on compensatory mechanisms activated during weight reduction.
Detailed description
This study included a sub-study (n=30) to determine the timeline over which compensatory mechanisms (at both the level of energy expenditure and appetite control system) are activated with progressive weight loss. Additional measurements were taken at day-3, 5 and 10 % weight loss, and after 4 weeks weight stabilization (after gradually reintroduction of food).
Interventions
BEHAVIORALMultidisciplinary outpatient program
Diet (phase 1) and multidisciplinary lifestyle intervention (phase 2)
BEHAVIORALInpatient lifestyle program
Diet (phase 1) and lifestyle intervention (phase 2)
Sponsors
St. Olavs Hospital
Norwegian University of Science and Technology
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
* volunteers from Central Norway * if female: taking oral contraceptives or post-menopausal * body mass index 30-45 kg/m2 * stable weight (\<2kg variation in the last 3 months) * not currently dieting to lose weight
Exclusion criteria
* Pregnancy * breast feeding * drug or alcohol abuse within the last two years * current medication known to affect appetite or induce weight loss * enrollment in another obesity treatment program * history of psychological disorders * history of eating disorders * history of diabetes type 1 or 2 * gastrointestinal disorders (particular cholelithiasis) * kidney -, liver -, lung- or cardiovascular disease * malignancies
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| body weight | 1 year (changes from baseline to one year) | body weight change after end of very-low calory diet |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| appetite, short-term | 10 weeks | assessed through: * the Three-Factor Eating Questionnaire (TFEQ) * fasting and postprandial release of appetite related hormones in blood samples, for a period of 3h (0, 30, 60, 120, 180 minutes), after a standard breakfast * feelings of hunger/fullness by a visual analog scale |
| exercise efficiency, short-term | 10 weeks | assessed through graded cycle ergometry and indirect calorimetry |
| physical activity level, short-term | 10 weeks | measurement with arm bands |
| resting metabolic rate, long-term | 1 year | using indirect calorimetry |
| resting metabolic rate, short-term | 10 weeks | using indirect calorimetry |
| exercise efficiency, long-term | 1 year | assessed through graded cycle ergometry and indirect calorimetry |
| physical activity level, long-term | 1 year | measurement with arm bands |
| Sleep duration and quality | Baseline, end of weigth loss phase and 1 year | Sleep duration and quality will be measured using The Pittsburgh Sleep Quality Index (PSQI) |
| appetite, long-term | 1 year | assessed through: * the Three-Factor Eating Questionnaire (TFEQ) * fasting and postprandial release of appetite related hormones in blood samples, for a period of 3h (0, 30, 60, 120, 180 minutes), after a standard breakfast * feelings of hunger/fullness by a visual analog scale |
Countries
Norway
Outcome results
None listed