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

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01371955
Recruitment Status : Completed
First Posted : June 13, 2011
Last Update Posted : November 15, 2013
Information provided by (Responsible Party):
University Hospital, Grenoble

Brief Summary:

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.

Condition or disease
Type 1 Diabetes Mellitus Diabetic Nephropathy

Detailed 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.

Study Type : Observational
Actual Enrollment : 162 participants
Observational Model: Cohort
Time Perspective: Prospective
Official Title: Impact of c242T Polymorphism of p22phox in the Development of Diabetic Nephropathy,in Caucasian Diabetic Type 1 Patient.
Study Start Date : January 2011
Actual Primary Completion Date : March 2013
Actual Study Completion Date : March 2013

Resource links provided by the National Library of Medicine

diabetic nephropathy group
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
patient with diabetic retinopathy defined as showing at least one micro aneurysm on retinography. Without nephropathy defined as above
no complication group
patient without diabetic nephropathy or retinopathy

Primary Outcome Measures :
  1. comparison of prevalence of homozygous polymorphism between the DN-group and the non-DN group [ Time Frame: on day 1 ]

Secondary Outcome Measures :
  1. comparison of polymorphism of p22phox between the ND group and the sub-group of non-ND patients with diabetic retinopathy only [ Time Frame: day 1 ]
  2. comparison of polymorphism prevalence between the 3 groups [ Time Frame: day 1 ]
  3. delay between diabetes diagnosis and ND onset by genetic polymorphism [ Time Frame: 20 years ]
    Kaplan Meier method

Other Outcome Measures:
  1. albuminuria [ Time Frame: day 1 ]

  2. HbA1c [ Time Frame: day 1 ]
    HbA1c in %

Biospecimen Retention:   Samples With DNA
We will include 60 patients to reach the required number. We take 2 blood samples: one for genetic analysis and one to determine HBA1c and plasma creatinine. We also take one urinary sample to determine the urinary albumine / creatinine ratio

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population
caucasian diabetic type 1 patients with more than 20 years of diabetes duration

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

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01371955

University Hospital of Grenoble
Grenoble, France, 38043
Sponsors and Collaborators
University Hospital, Grenoble
Principal Investigator: BENHAMOU pierre yves, MD PhD service de diabétologie

Responsible Party: University Hospital, Grenoble Identifier: NCT01371955     History of Changes
Other Study ID Numbers: 1020
2010-A01074-35 ( Registry Identifier: ID RCB )
First Posted: June 13, 2011    Key Record Dates
Last Update Posted: November 15, 2013
Last Verified: November 2013

Keywords provided by University Hospital, Grenoble:
diabetic nephropathy
Type 1 Diabetes Mellitus with Diabetic Dermatitis
more than twenty years of diabetes duration
older than 18 years
no nephropathy other than diabetic nephropathy

Additional relevant MeSH terms:
Diabetes Mellitus
Diabetes Mellitus, Type 1
Kidney Diseases
Diabetic Nephropathies
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases
Autoimmune Diseases
Immune System Diseases
Urologic Diseases
Diabetes Complications