Clinical trial NCT00995631: Following Lipectomy to Understand Adipose Tissue Re-accumulation
Official title: Regional Fat Re-accumulation Following Lipectomy in Pre- and Post-menopausal Women
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Menopause
Pre-menopause
Keywords: liposuction
adipose tissue
dietary fatty acids
triglyceride storage
Normal healthy aging
Lead sponsor: University of Colorado, Denver
Sponsor class: OTHER
First posted: 2009-10-15
Enrollment: 53
Sex: FEMALE
Minimum age (years): 35
Maximum age (years): 60
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: The typical female pattern of accumulating fat in the hips and thighs has long been thought to confer less risk for disease than the typical male abdominal fat pattern. However, leg fat may not simply be benign with respect to disease risk, but may in fact protect against cardiovascular disease risk. Although the mechanism for this is unknown, the investigators hypothesize that removing a portion of this important fat depot (via liposuction) could increase disease risk. Such unfavorable results may or may not be transient depending on an individual's ability to defend their fat mass. Because sex hormones appear to play a role in regional fat accumulation, the investigators hypothesize that estrogen-deficient postmenopausal women may have an augmented abdominal fat accumulation and an attenuated hip and thigh re-accumulation compared to premenopausal women following lipectomy and compared to non-surgical controls. As a result, the increased abdominal fat accumulation may worsen disease risk in postmenopausal women. Menopause-related differences in fat storage at baseline are also expected to determine the degree to which lipectomy alters disease risk and the propensity for AT re-accumulation.

Detailed description: Lipectomy is the most frequently performed aesthetic surgery in the U.S. today and is considered permanent, by The American Society for Aesthetic Plastic Surgery, but no long term follow-up studies have been done to verify this assertion. Indeed, animal studies suggest rapid adipose tissue (AT) re-accumulation after lipectomy is common and may even be accompanied by unfavorable changes in disease risk. Recent studies in humans have focused on abdominal lipectomy as a means of reducing metabolic disease risk in obese premenopausal women. However, none of these studies evaluated AT re-accumulation or reported long-term (\>6 mo) changes in metabolic outcomes, and none have evaluated the effect of removing femoral AT despite this being a common site for lipectomy in women and despite the apparent cardioprotective benefit of lower body adiposity. Further, none of these studies included postmenopausal women who are at an increased risk of abdominal AT accumulation. It is the investigator's overall working hypothesis that removal of femoral AT by lipectomy may worsen metabolic disease risk (as measured by postprandial lipemia) in estrogen-deficient postmenopausal women who, in contrast to premenopausal women, will accumulate AT in the abdominal rather than the femoral region. The global aims of this study are to determine whether: 1) there are menopause-related differences in regional (abdominal vs. femoral) AT re-accumulation following lipectomy; and 2) changes (removal and regain) in femoral AT mass alter postprandial triglyceride clearance and storage of meal-derived fatty acids. Further, the investigators postulate that menopause-related differences in postprandial lipemia and handling of dietary fatty acids will determine the degree to which femoral lipectomy worsens these parameters. Pre- and postmenopausal women (n=80) will be randomly assigned to either femoral lipectomy or control (no surgery). All eligible volunteers will undergo testing at the beginning of the study and at 2, 8, and 14 months following lipectomy. Measurements will include body composition assessments, meal tests and AT biopsies to assess lipectomy-related changes in: 1) abdominal and femoral fat mass; 2) systemic postprandial triglyceride excursions; and 3) storage of dietary fatty acids in AT. These studies are designed to evaluate the effect of femoral lipectomy on regional AT re-accumulation and metabolic disease risk in pre- and postmenopausal women.

Eligibility criteria: Inclusion Criteria:

* post-menopausal (no menses for 12mo or oophorectomy w/ follicle-stimulating hormone (FSH)\>30 IU/L) OR- pre-menopausal (regular menses 28+/-3d)
* BMI \>20 and \<30 kg/m2)
* weight stable (+/- 2kg in past 2mo)
* non-smoking
* no use of hormone therapies or oral contraceptives
* actively seeking liposuction of the hips and thighs
* good femoral lipectomy candidates as determined by cosmetic surgeon

Exclusion Criteria:

* severe hypertriglyceridemia (\>400 mg/dL)
* medications known to affect lipid metabolism
* elevated resting blood pressure (Systolic \>140 mm Hg,Diastolic \>90 mm Hg)
* history of lipectomy or gastric bypass surgery
* body dysmorphic disorder
* pregnant, lactating or intention of becoming pregnant
* indication of high surgical risk (e.g., abnormal resting ECG, history of thromboembolism, valvular heart disease)

Primary outcomes:
measure: Postprandial triglyceride excursions (incremental areas)
timeFrame: Baseline, 2Mo, and 14Mo
measure: Abdominal and femoral fat mass accumulation
timeFrame: Baseline, 2Mo, and 14Mo
Secondary outcomes:
measure: Triglyceride storage (14C-oleic acid incorporation into abdominal and femoral adipose tissue)
timeFrame: Baseline, 2Mo, and 14Mo
measure: Lipoprotein lipase activity (abdominal and femoral adipose tissue)
timeFrame: Baseline, 2Mo, and 14Mo
Other outcomes:
Locations:
city: Aurora
country: United States
facility: University of Colorado Anschutz Medical Campus
state: Colorado
Study officials:
affiliation: University of Colorado, Denver
name: Rachael E Van Pelt, PhD
role: PRINCIPAL_INVESTIGATOR
References: