Impact of c242T Polymorphism of p22phox in Diabetic type1 Nephropathy (NEPHRODIANOX)

Grenoble Alpes University Hospital Center (CHU)

Status: Completed

Conditions: Diabetic Nephropathy; Type 1 Diabetes Mellitus

Study type: Observational

Funder types: Other

Identifiers

NCT01371955

1020

2010-A01074-35 (Registry Identifier)

Details and patient eligibility

About

The physiopathology of diabetic nephropathy (DN) is unclear. To investigate risk factor, the investigators choose to look about some oxidative stress genes. Today a one-gene explanation is not really possible. So the theory of some genetic predisposition to DN is more likely.

The aim of the study is to look about the association of the C282T polymorphism of P22phox, a sub unit of the nicotinamide adenine dinucleotide phosphate-oxidase (NADPH oxidase) in the occurrence of DN. To follow the oxidative stress pathway of the DN, the investigators also investigate three other polymorphisms: -429 T/C, -374 T/A polymorphism of advanced glycation end-products receptor (AGER) and the p.Arg261Gln polymorphism of the 12 lipoxygenase (ALOX 12). Discordant data suggest a link between the first 2 polymorphisms and DN. The last polymorphism is correlated to albuminuria in diabetic patients.

Full description

To avoid confounding factors, we choose type 1 diabetic patients. We plan, with the data of literature a number need to be significative with a power of 80% and an Alpha risk at 5%, the inclusion of 160 patients for our primary analyze of p 22 phox. Those patients are included consequentially from the diabetic consultation of the university hospital of Grenoble, if they have a history of more than 20 years of diabetes. Those patients have been separated according to the existence of DN, and their polymorphism. Then we estimate with the Fisher test the prevalence of DN in risky patient, and the prevalence of the risky phenotype in the nephropathic patients. Then we investigate with the same statistical test the -429 T/C,he -374 T/A AGER and p.Arg261Gln 12 ALOX polymorphisms.

Enrollment: 162 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• caucasian
• diabetic type 1
• older than 18 years old
• written consent

Exclusion criteria

• other etiology of diabetic nephropathy
• pregnancy
• other type of diabetes

Trial design

162 participants in 3 patient groups

diabetic nephropathy group

Description:

patient with diabetic nephropathy, defined as Albuminuria \> 30 mg/day or urinary Albumine/ creatinine ratio \> 3 mg/mmol ; or GFR estimated by MDRD less than 60 ml/min.1,73m². With no other etiology of diabetic nephropathy.

diabetic retinopathy group

Description:

patient with diabetic retinopathy defined as showing at least one micro aneurysm on retinography. Without nephropathy defined as above

no complication group

Description:

patient without diabetic nephropathy or retinopathy