Isocaloric Dietary Interventions for Insulin Resistance and the Metabolic Syndrome

NCT01040663 | Completed

• 1 other identifier: LNE-0673
• Study Type: interventional
• Target: 42
• Locations: 1 country
• Sites: 1

Brief Summary

In recent decades, the prevalence of obesity has increased dramatically in the United States. Obesity has been associated with an increased risk of the metabolic syndrome, which is characterized by a cluster of metabolic derangements, including insulin resistance, high blood sugar, high triglycerides, low high density lipoprotein (HDL) cholesterol levels, high blood pressure, and inflammation. Lifestyle interventions, including dietary modification, physical activity, and weight loss, form the basis of treatment for individuals with the metabolic syndrome. However, the optimal composition of the diet is not known at this time. Furthermore, due to hormonal and metabolic changes that accompany weight loss, most people find it very difficult to maintain significant weight reductions over time. As a result, weight regain is exceedingly common.

Conditions

Obesity

Outcome Measures

Primary Outcomes (1)

• Change in hepatic insulin sensitivity from the first testing battery (on Western diet) to the second testing battery (on study diet). Hepatic insulin sensitivity will be assessed using the homeostatic model assessment plasma

  3 years

Secondary Outcomes (1)

• Peripheral (muscle) insulin sensitivity, Glycemic control,Glycemic responses to a representative breakfast, Systemic inflammation, blood endotoxin levels, lipids, Systolic and diastolic blood pressure, body composition, and dietary satisfaction.

  3 years

Study Arms (3)

Dash Diet

OTHER

Subjects receive DASH diet for 4 weeks

Other: Dietary intervention

Low GI Diet

OTHER

Subjects will receive Low GI diet for 4 weeks

Other: Dietary intervention

Western Style Diet

OTHER

Subjects will receive western style diet for 4 weeks

Other: Dietary intervention

Interventions

Dietary intervention OTHER

Subjects will be randomly assigned to receive 1 of 3 diets for 4 weeks.

Dash Diet; Low GI Diet; Western Style Diet

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Nonsmoking men and postmenopausal women, ages 18 - 65. Premenopausal women who would not be expected to have significant fluctuations in estrogen and progesterone levels during the study (e.g. those on continuous monophasic hormonal contraception) may be included in the study at the discretion of the PI or designated study staff.
• Body mass index (BMI) of at least 27 kg/m2
• Body weight \< 200 kg (the weight limit of the Bod Pod® scale)
• Evidence of insulin resistance, as suggested by any one of the following:
• Fasting glucose of 100 mg/dL or higher
• Impaired glucose tolerance, with a glucose concentration of 140 mg/dL or higher, 2 hours after a 75-gram oral glucose challenge.
• A fasting insulin concentration of 9 mIU/L or higher
• Willingness to consume only study food and drink for the duration of the study
• Willingness to be randomized to any one of the three study diets
• If applicable, willingness to maintain consistent intake of coffee and/or tea during the inpatient periods (due to the potential effects of these drinks on inflammatory markers)
• Willingness to avoid the use of all over-the-counter or prescription vitamins, dietary supplements, and herbal products during the study. At the PI's discretion, other nutritional supplements, such as iron, may also be continued during the study if they are deemed medically necessary and are unlikely to influence study results.
• If applicable, willingness to continue current antihypertensive medications (especially angiotensin converting enzyme inhibitors and angiotensin receptor blockers, which may affect levels of inflammatory markers) at the same dose and schedule throughout the study,unless a change is advised by the subject's primary care provider or the study investigators
• Willingness to avoid the use of non-steroidal anti-inflammatory drugs (NSAIDS), including low-dose daily aspirin, throughout the inpatient admission, (due to the potential effects of these agents on inflammatory markers).
• at least two of the following:
• waist circumference greater than 35" in women or 40" in men

You may not qualify if:

• Current tobacco smoking
• History of a bleeding disorder
• Known or suspected cardiovascular disease, including angina, myocardial infarction, medical or surgical treatment for atherosclerotic disease, arrhythmia, or congestive heart failure
• Blood pressure higher than 145/90 after 10 minutes of rest, confirmed on two or more visits, or treatment with three or more antihypertensive agents at any blood pressure. Subjects taking up to two antihypertensive agents may be included in the study if 1) BP is at least 115/75 mmHg but \< 145/90 mmHg on these agents and 2) they agree to remain on the same medications (and same dosages) during the study, unless otherwise advised by a primary care provider or study investigators (e.g. the dosage may be reduced or the medication may be stopped if signs or symptoms of hypotension develop during the study)
• Fasting glucose \> 165 mg/dL, glycosylated hemoglobin \> 8%, or any treatment with oral hypoglycemic agents, insulin sensitizing agents (e.g. metformin or thiazolidinediones), insulin, incretin mimetics (e.g. exenatide), amylin analogues (e.g. pramlintide), or endocannabinoid receptor antagonists (e.g. rimonabant). Volunteers with type 2 diabetes and a glycosylated hemoglobin level of 7.5% or higher will be encouraged to discuss treatment options (e.g. pharmacotherapy versus study participation) with their primary care providers before enrolling in the study
• History of chronic glucocorticoid use, oral glucocorticoid use for more than 5 days in the previous year, or anticipated treatment with oral or intravenous glucocorticoids during the study period. Daily, low-dose, inhaled or nasal glucocorticoids may be acceptable in some cases, at the discretion of the Principal Investigator.
• Current treatment with over-the-counter or prescription weight loss medications, such as orlistat or sibutramine
• History of bariatric surgery
• Current treatment with any cholesterol-lowering medications, such as statins, niacin,fibrates, or ezetimibe
• Hyperthyroidism or untreated hypothyroidism. Subjects with chronic, treated, stable hypothyroidism may be included in the study at the discretion of the Principal Investigator
• Obstructive sleep apnea, or significant symptoms suggestive of this condition
• Active gallstone disease
• Known history of chronic hepatitis, or liver enzymes (AST or ALT) more than 2.5 times the upper limit of normal
• Known infection with HIV or confirmed positive test for HIV antibody
• Inflammatory bowel disease, active cancer, or any other medical condition that may cause significant acute weight loss or gain

Sponsors & Collaborators

• Rockefeller University: lead

Study Sites (1)

The Rockefeller University

New York, New York, 10065, United States

Location

MeSH Terms

Conditions

Obesity

Interventions

Diet Therapy

Condition Hierarchy (Ancestors)

Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Nutrition Therapy; Therapeutics

Study Officials

• Lisa Neff, MD

  The Rockefeller University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 24, 2009
• First Posted: December 29, 2009
• Study Start: July 1, 2009
• Primary Completion: January 1, 2013
• Study Completion: January 1, 2013
• Last Updated: April 10, 2013

Record last verified: 2013-04

Locations

US (1)