Obesity
Conditions
Keywords
Obesity, sibutramine, eating behavior
Brief summary
Obesity is a major public health concern, and the search for useful pharmacologic interventions is ongoing. This study aims to develop a comprehensive series of assessments to directly assess eating behavior, cognitive functioning, and psychological functioning under sibutramine and placebo conditions.
Detailed description
We will recruit 48 moderately obese men and women seeking weight-loss treatment to participate in a 3-week, randomized, double-blind, cross-over trial of sibutramine 15mg or placebo daily. At the end of weeks 1 and 3, subjects will be asked to participate in a two-day/three-night stay in the Residential Laboratory or Biological Studies Unit of the New York State Psychiatric Institute for comprehensive assessments. The major outcome variable will be the difference in total daily caloric intake between sibutramine and placebo. Assessments will concentrate on three main components of eating behavior: eating patterns, psychological processing, and neurocognitive function. Eating behavior studies will examine objective variables such as meal size, meal frequency, and subjective aspects of eating such as hunger and fullness. Psychological studies will measure hedonics, including craving, behavioral restraint, and impulsivity. Neurocognitive function assessment will gather information about decision-making, such as the effects of distractors (food and non-food) on task performance. Additionally, drawing from the field of behavioral neuroeconomics, tasks that assess decision-making and the influence of irrational factors on decisions will be assessed. Neuroimaging (fMRI) procedures will also be conducted, and will augment the psychological and neurocognitive assessments by providing a window into the underlying neural circuitry involved. Following the double-blind phase, participants will be offered open treatment with sibutramine for weight loss.
Interventions
DRUGSibutramine
1 week of active sibutramine (15mg)
DRUGPlacebo
2 weeks of placebo
Sponsors
AstraZeneca
New York State Psychiatric Institute
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
OTHER
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
No
Inclusion criteria
* moderately obese * stable weight for a minimum of 3 months * systolic blood pressure less than or equal to 140 mm Hg * diastolic blood pressure less than or equal to 90 mm Hg * pulse less than or equal to 95 beats per minute * English language proficiency
Exclusion criteria
* on medications known to affect appetite, weight, or metabolism * current or past history of: binge eating disorder, anorexia nervosa or bulimia nervosa, major depression * current or past evidence of psychosis, bipolar illness * current or past history of alcohol or drug abuse or dependence * known history of learning disorder or developmental disability * current or past attention deficit hyperactivity disorders * low platelet count * current diabetes mellitus * uncontrolled asthma, or controlled only with oral steroids * hypothyroidism not adequately treated * pregnancy, planning to become pregnant, or lactation within the previous 6 months * history of neurological disorder or injury * history of moderate or severe head injury * waist circumference greater than 188 cm * indwelling metallic object, non-removable metal jewelery, medicinal patch or recent metallic ink tattoo * pacemaker * metallic implants * medication patches * significant claustrophobia * color blindness
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 24 Hour Measured Caloric Intake | 1 week | The primary outcome measure is 24-hour food intake assessed by 24 hour weighed intake after one week of sibutramine administration compared to one week of placebo administration. |
Countries
United States
Participant flow
Recruitment details
45 potential participants were screened for eligibility between February, 2009 and July 2010 at an academic medical center in New York City, NY.
Pre-assignment details
14 of 45 patients were randomized. Of those not randomized, 21 did not meet inclusion criteria.
Participants by arm
| Arm | Count |
|---|---|
| Sibutramine First, Then Placebo Participants in this group were randomized to begin with 7 days of 15mg of sibutramine, followed by 14 days of placebo. | 4 |
| Placebo First, Then Sibutramine Participants in this group were randomized to begin with 14 days of placebo, followed by 7 days of 15mg of sibutramine. | 6 |
| Total | 10 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Protocol Violation | 4 | 1 |
Baseline characteristics
| Characteristic | Placebo First, Then Sibutramine | Sibutramine First, Then Placebo | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical Between 18 and 65 years | 6 Participants | 4 Participants | 10 Participants |
| Age, Continuous | 39 years STANDARD_DEVIATION 11 | 33 years STANDARD_DEVIATION 6 | 36 years STANDARD_DEVIATION 10 |
| Region of Enrollment United States | 6 participants | 4 participants | 18 participants |
| Sex: Female, Male Female | 5 Participants | 4 Participants | 9 Participants |
| Sex: Female, Male Male | 1 Participants | 0 Participants | 1 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 9 | 0 / 9 |
| other Total, other adverse events | 7 / 9 | 5 / 9 |
| serious Total, serious adverse events | 0 / 9 | 0 / 9 |
Outcome results
Primary
24 Hour Measured Caloric Intake
The primary outcome measure is 24-hour food intake assessed by 24 hour weighed intake after one week of sibutramine administration compared to one week of placebo administration.
Time frame: 1 week
Population: This is a cross over design study. All participants received sibutramine and placebo. The sibutramine arm listed here includes all participants who received sibutramine (regardless of whether they received it first or second). The placebo arm included all those who received placebo (regardless of whether they received it first or second).
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Sibutramine | 24 Hour Measured Caloric Intake | 1923 kcal | Standard Deviation 655 |
| Placebo | 24 Hour Measured Caloric Intake | 2373 kcal | Standard Deviation 774 |
p-value: <0.004paired sample t-test, two tailed