Clinical Trial: Almond Effects on Glucose Intolerance Study

Study Status: Enrolling by invitation
Recruit Status: Enrolling by invitation
Study Type: Interventional

Official Title: Almond Effects on Glucose Intolerance Study (AEGIS)

Brief Summary:

Diabetes is a major cause of morbidity and mortality worldwide. Prevention of diabetes is an important goal. The progression from impaired glucose tolerance to diabetes is thought to be promoted by the toxic effects of hyperglycemia on pancreatic beta cells. One of the main defects causing postprandial hyperglycemia in individuals with impaired glucose tolerance is reduced first phase (immediate) insulin release. The investigators hypothesis is that consuming a nutritional preload--a low-calorie, nutritionally balanced snack--30 minutes before ingesting a carbohydrate load, will moderate the hyperglycemic response to subsequent carbohydrate challenge and reduce glucotoxicity by stimulating insulin release and synthesis.

The aim of this study is to test this hypothesis by comparing the standard 75-gram, two-hour oral glucose tolerance test (OGTT) response of 30 fasting adults who have impaired glucose tolerance to their OGTT response when the test is preceded by ½ ounce (14 grams) of dry-roasted, unsalted almonds. A pre-load interval of 30 minutes was chosen so that the peak of phase 2 (delayed) insulin response to the pre-load (45-60 minutes) would coincide with the timeframe of the steepest OGTT rise in glucose (15 to 30 minutes post challenge).

The investigators hypothesize that the one-hour OGTT glucose level will be approximately 40 mg/dl lower when participants consume the pre-OGTT almond snack, compared to their one-hour glucose level on the standard two-hour OGTT. The two-hour OGTT glucose level is unlikely to show a statistically significant difference between the almond pre-test snack and control standard OGTT conditions.

Detailed Summary:

The study will be conducted at Physicians at Sugar Creek (PSC)—the model family practice center for the Memorial Family Medicine Residency Program. The ethnicity of PSC patients is approximately 30% non-Hispanic white, 30% Hispanic, 30% African-American, and 10% Asian.

Potential participants will be identified by searching PSC electronic medical records (Centricity) to find adults aged 18-75 with impaired glucose tolerance, without diabetes (one-hour oral glucose tolerance test result >160 md/dl and two-hour OGTT result <200 mg/dl), without hypoglycemic medications and corticosteroids on their active medications list, and without almond allergy on their allergy list.

Recruitment flyers will be posted in the clinic to encourage interested individuals to contact the investigators about their potential study eligibility. The investigators will also approach previously identified potentially eligible patients during routine clinical visits in the clinic, to elicit their interest in participating in the study. Those expressing interest will be scheduled for an intake visit with an investigator, to further ascertain their eligibility and invite eligible individuals to take part in the study. Interested eligible individuals who render verbal and written informed consent will then be instructed in the study protocol and scheduled for their first data gathering visit.

Each participant will be scheduled to undergo two 2-hour oral glucose tolerance tests (OGTT), starting between 7:00 and 9:30 a.m., one to four weeks apart. Test A will be a standard 75-gram OGTT. Test B will be an OGTT that will begin 30 minutes after ingestion of a low-carbohydrate pre-load "snack" consisting of 1/2 oz (14 grams) of unsalted, dry-roasted almonds (12 average size almonds). Each pa
Sponsor: Memorial Hermann Health System

Current Primary Outcome: One-hour OGTT result [ Time Frame: 60 minutes into 2-hour oral glucose tolerance test ]

Original Primary Outcome: Same as current

Current Secondary Outcome: Two-hour OGTT result [ Time Frame: 120 minutes into 2-hour oral glucose tolerance test ]

Original Secondary Outcome: Same as current

Information By: Memorial Hermann Health System

Dates:
Date Received: October 6, 2014
Date Started: December 2014
Date Completion: March 2016
Last Updated: March 15, 2016
Last Verified: March 2016