Health Effects of Liposuction in Overweight Women With Elevated Insulin Levels, Impaired Glucose Tolerance and/or Type 2 Diabetes

Obesity Clinical Trial

Official title: A Pilot Study of the Metabolic Effects of Large Volume Liposuction in Overweight Women With Hyperinsulinemia, Impaired Glucose Tolerance and/or Type 2 Diabetes

Status Completed

Clinical Trial Summary

This study is for women who have already decided to undergo liposuction at Georgetown University Medical Center in Washington, D.C. To take part in this study, a woman must first meet with the plastic surgeons there, and be accepted by them to have liposuction. This study will investigate whether large volume liposuction improves risk factors for heart disease in overweight women with type 2 (adult onset) diabetes, impaired glucose tolerance, or elevated blood insulin levels. Large volume liposuction is the surgical removal of at least 10 pounds (4.5 kg) of body fat, usually from the abdomen, hips or chest. Risk factors for heart disease include high blood pressure and elevated levels of blood lipids (cholesterol and triglycerides), blood glucose (sugar), and blood insulin. Subjects who participate in all parts of this study will receive a total of $930.00.

Overweight women 18 years or older with high blood insulin levels, impaired glucose tolerance, or type 2 diabetes, who are planning to have large volume liposuction performed at Georgetown University Medical Center in Washington, D.C., may be eligible for this study. For a subject to be accepted into this study, she must first meet with the plastic surgeons at Georgetown University Medical Center, and they have to agree to perform large volume liposuction. The decision that someone is suitable for liposuction is not under the control of the NIH or of any NIH investigator.

Those enrolled will undergo the following procedures at four separate times - before undergoing liposuction, 4 weeks after surgery, 4 months after surgery and 1 year after surgery:

• Body measurements - taken with calipers to measure several skinfold thicknesses (the width of a fat fold) and with a tape measure to measure the circumference of parts of the body.

• Urine sample and 6-hour urine collection - to test for pregnancy and to evaluate kidney function.

• Glucose tolerance test - measures insulin sensitivity and how the body uses sugar, how well insulin works, and insulin sensitivity. The procedure involves placement of two catheters (thin, flexible tubes) through a needle into a vein in each arm. Sugar water is infused into one catheter and 20 minutes into the test a small amount of insulin is injected. Blood samples are drawn from the other catheter at frequent intervals for a total of 5 hours.

• Electrocardiogram (ECG) and echocardiography - measure the heart's electrical activity and function.

• Abdominal computerized tomography (CT) scan - produces images for measuring body fat in the abdomen. (not done at the 4-week visit). Takes about half an hour to complete.

• DXA X-ray - measures body fat, muscle and bone mineral content. Takes about half an hour to complete.

• Bod Pod - capsule-like device used to determine the proportion of body weight composed of fat and non-fat tissue. Takes less than 10 minutes

• Bioelectric impedance analysis device - measures the proportions of body fat based on electrical conduction of a small electric current. Takes 2-3 minutes.

• 24-hour blood pressure monitoring - a device attached to a blood pressure cuff strapped to the arm measures blood pressure every 15 to 30 minutes continuously for 24 hours.

• Vascular reactivity tests - a blood pressure cuff is inflated for about 4 minutes before deflating, providing information on the function of the small blood vessels in the skin, as well as an idea of the function level of small blood vessels elsewhere in the body. Takes half an hour.

• Blood samples - collected to evaluate kidney and liver function and to measure body lipids, such as cholesterol, minerals, and other substances.

Clinical Trial Description

Obesity is a major predisposing factor for future Type 2 diabetes because it is often associated with insulin resistance and impaired glucose tolerance. Insulin resistance has been suggested as the common link for other aspects of the cardiac dysmetabolic syndrome that includes hypertension, dyslipidemia, obesity, and macrovascular arterial disease. There are racial disparities in the prevalence of both obesity and Type 2 diabetes: Compared with non-Hispanic Caucasians, African American women have almost twice the prevalence of overweight, obesity, and Type 2 diabetes.

Because data from predominantly Caucasian populations suggest that the quantity of truncal (sometimes called upper body) adipose tissue, which includes the adipose tissue surrounding the abdominal viscera, is far more important for risk stratification than that found in the limbs or buttocks, which contain subcutaneous adipose tissue, it has been presumed that attempts at treatment of obesity should concentrate on reducing visceral fat. However, despite their greater risks for the complications of obesity, African Americans have less visceral abdominal adipose tissue than Caucasians matched for body weight. Further, recent metabolic studies suggest that upper body subcutaneous adipose tissue may play a significant role, particularly for African Americans, in the comorbid metabolic conditions associated with obesity.

With the advent of the large volume liposuction technique, selective removal of substantial quantities of subcutaneous adipose tissue has become possible. It is unknown whether the complications of obesity can be ameliorated by removal of subcutaneous adipose tissue, but one preliminary study suggests that fasting hyperinsulinism can be improved by this approach.

We propose to conduct a pilot study of 10 patients (five Caucasians and five African-Americans) who plan to undergo liposuction. We will investigate how large volume liposuction affects the metabolic complications of obesity in overweight patients who have hyperinsulinemia, impaired glucose tolerance, or type 2 diabetes. We will investigate the effects of liposuction on various indices of the cardiac dysmetabolic syndrome by performing studies of insulin sensitivity and lipid metabolism at four time points: before large volume liposuction, 1 month after liposuction, 4 months after liposuction, and 1 year after liposuction. At each visit we will study body composition, blood pressure, cardiac function, dietary habits, insulin insensitivity, free fatty acids, and lipid profiles. ;

Study Design

N/A

Related Conditions & MeSH terms

• Diabetes Mellitus, Non Insulin Dependent
• Diabetes Mellitus, Type 2
• Glucose Intolerance
• Hyperinsulinemia
• Hyperinsulinism
• Obesity

• NCT number: NCT00005760
• Study type: Observational
• Source: National Institutes of Health Clinical Center (CC)
• Status: Completed
• Phase: N/A
• Start date: May 2000
• Completion date: January 2002