Advanced Glycation End-products, Inflammation and Vascular Health in Chronic Kidney Disease

Study Overview
=================
Brief Summary
-----------------
The purpose of the study is to learn more about how advanced glycation end-products can affect insulin resistance, inflammation and blood vessel health in people with kidney disease.

Detailed Description
-----------------
Advanced glycation end-products (AGEs) are compounds that form when sugars abnormally attach to proteins or lipids. High levels of AGEs in the blood may cause inflammation, problems with controlling blood sugar, and problems with the health of blood vessels. Many of the foods we commonly eat have high amounts of AGEs, which may increase AGEs in the blood of people with kidney disease. The amount of AGEs in foods can be lowered when prepared using special cooking techniques such as using moist heat or longer cooking times at lower temperatures. New research has shown that preparing food in this way can lower inflammation and improve blood vessel health in people with normal kidney function. In this study, the investigators would like to examine the effect of lowering the AGE content of foods on inflammation, blood sugar control, and blood vessel health in individuals with mild to moderate chronic kidney disease.

Official Title
-----------------
Advanced Glycation End-products, Inflammation and Vascular Health in Chronic Kidney Disease

Conditions
-----------------
Chronic Kidney Disease

Intervention / Treatment
-----------------
* Other: Research diet


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Patients with mild to moderate CKD (estimated glomerular filtration rate 15 - 59 ml/min/1.73m2). Exclusion Criteria: Current or past use of anti-glycemic medications Fasting glucose > 126 mg/dl on screening visit or positive glucose on urine dipstick Nephrotic-range proteinuria (≥ 3.5 grams per day as assessed by a spot urine albumin to creatinine ratio obtained at the screening visit) Pregnancy or breast-feeding Clinical need for a specialized diet (low sodium, low potassium, etc.) or religious dietary restrictions. New or recent change (< 3 months) in dosage of medications known to affect vascular reactivity- angiotensin converting enzyme inhibitors, angiotensin II receptor blockers, beta-blockers, calcium channel blockers, HMG-CoA reductase inhibitors, etc. Current smoking or recent (< 6 months) cessation of smoking. Poorly controlled hypertension (≥ 140 mm Hg systolic or 90 mm Hg diastolic), or prior history of malignant hypertensive episode (SBP > 200) off of blood pressure medications. Participants with rapidly advancing renal failure. Severe anemia, defined as a hemoglobin < 8 g/dL for men and < 6 g/dL for women.

Ages Eligible for Study
-----------------
Minimum Age: 19 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Dietary intervention<br>All participants will be fed a high AGE diet followed by a low AGE diet (single arm study) | Other: Research diet<br>* Participants will be provided specially prepared meals to eat at home for three weeks. During the first week, participants will eat foods that have standard amounts of AGEs in them (this is called the control diet). During the second and third weeks, participants will eat the same foods, only they will be prepared in our kitchen in a way that limits the amount of AGEs in them (called the intervention diet).<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| N-epsilon-carboxymethyllysine (CML) | Change in CML concentrations | baseline, one week and three weeks | 
| Inflammatory biomarkers | Change in interleukins 1, 6 and 10, c-reactive protein | baseline, one week and three weeks | 
| Indices of insulin sensitivity | Change in HOMA-IR | baseline, one week and three weeks | 
| Flow-mediated dilation (FMD) | Changes in brachial FMD | one week and three weeks | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Advanced glycation end-products, chronic kidney disease, nutrition, inflammation, insulin resistance, endothelial function