Klotho Gene Polymorphism in Dialyzed Patients With Hyperphosphatemia

This study has been terminated.
(terminated)
Sponsor:
Collaborator:
Institut National de la Santé Et de la Recherche Médicale, France
Information provided by:
Assistance Publique - Hôpitaux de Paris
ClinicalTrials.gov Identifier:
NCT00374712
First received: September 12, 2005
Last updated: November 6, 2007
Last verified: November 2007
  Purpose

Patients with chronic kidney disease (CKD) and those with end-stage renal disease (ESRD) undergoing renal replacement therapies show elevated serum phosphate levels which predispose them to cardiovascular calcifications and high risks of death from cardiovascular diseases. However, in certain patients hyperphosphatemia is not related to dialysis insufficiency, excessive daily dietary phosphorus intake or high serum parathyroid hormone (PTH) levels, suggesting that other mechanisms could be involved. Transgenic mice lacking the klotho gene showed a phenotype which resembles that of dialyzed ESRD patients, in the sense that they have hyperphosphatemia, vascular calcifications, and a short lifespan. This study will analyze whether functional polymorphisms or variants in the human klotho gene are associated with hyperphosphatemia in these patients.


Condition
Chronic Kidney Disease
End Stage Renal Disease
Hyperphosphatemia
Renal Osteodystrophy

Study Type: Observational
Study Design: Time Perspective: Prospective
Official Title: Study of Klotho Gene Polymorphisms in the Regulation of Serum Phosphate Levels in Hemodialysis Patients

Resource links provided by NLM:


Further study details as provided by Assistance Publique - Hôpitaux de Paris:

Biospecimen Retention:   Samples With DNA

DNA


Enrollment: 40
Study Start Date: January 2005
Study Completion Date: November 2007
Detailed Description:

The entire coding region of the klotho gene will be sequenced looking for functional variants and polymorphisms that differentiate two groups of adult dialyzed ESRD patients, matched for age and gender, and with comparable values for dialysis dose and daily protein intake. These two groups consist of one group of 20 adult, dialyzed patients with serum phosphate levels > 2.50 mM compared to another group of 20 adult, dialyzed ESRD patients with serum phosphate levels < 1.50 mM. The results of this study will allow to determine whether there is a relationship between extreme hyperphosphatemia and klotho gene polymorphisms in dialysed ESRD patients.

  Eligibility

Ages Eligible for Study:   18 Years to 80 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population

Adult, end-stage renal disease patients treated by standard hemodialysis

Criteria

Inclusion Criteria:

Group 1

  • Stable hemodialysis patients for at least 3 months
  • Phosphatemia > 2.5 mM
  • Kt/V > 1.2
  • Total weekly phosphate removal > 75 millimoles

Group 2

  • Stable hemodialysis patients for at least 3 months
  • Phosphatemia < 1.5 mM
  • Kt/V > 1.2
  • Total weekly phosphate removal > 25 millimoles

Exclusion Criteria:

  • Age > 80 years
  • Insufficient dialysis dose (Kt/V < 1.2)
  • Total weekly phosphate removal < 25 mM
  • Problems with vascular access for hemodialysis (central catheter, arteriovenous [A-V] fistula dysfunction)
  • Methods of dialysis different than the classical hemodialysis (peritoneal, hemofiltration, or hemodiafiltration with or without acetate)
  • Intolerance or allergy to ARYLANE M9 dialyzers
  • Hypocalcemia < 2.0 mmol/liter
  • Hypophosphatemia < 0.6 mmol/liter
  • Daily protein intake < 0.6 g/kg/j
  • Parathyroidectomy at least 3 months prior to the study
  • Evolutive neoplasia with or without secondary lytic bone lesions
  • Intestinal malabsorption
  • Alcoholism
  • Corticotherapy
  • Treatment by bisphosphonates, fluor or recombinant PTH
  • Malnutrition (body mass index [BMI] < 15)
  • Amputation of lower members (> 10% of total body)
  • Prolonged immobilization
  • Secondary hyperparathyroidism (PTH > 1400 pg/ml)
  • Vitamin D deficiency (25OHD3 < 10 ng/ml)
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00374712

Locations
France
Clinique de l'Orangerie - Service de Néphrologie et Dialyse
Aubervilliers, France, 93300
Sponsors and Collaborators
Assistance Publique - Hôpitaux de Paris
Institut National de la Santé Et de la Recherche Médicale, France
Investigators
Principal Investigator: Pablo URENA TORRES, MD Clinique de l'Orangerie, France
  More Information

Publications:
ClinicalTrials.gov Identifier: NCT00374712     History of Changes
Other Study ID Numbers: P031010, CRC 03161
Study First Received: September 12, 2005
Last Updated: November 6, 2007
Health Authority: France: Afssaps - Agence française de sécurité sanitaire des produits de santé (Saint-Denis)

Keywords provided by Assistance Publique - Hôpitaux de Paris:
Phosphate
Dialysis
Klotho
Hemodialysis

Additional relevant MeSH terms:
Kidney Diseases
Renal Insufficiency, Chronic
Kidney Failure, Chronic
Hyperphosphatemia
Renal Osteodystrophy
Urologic Diseases
Renal Insufficiency
Phosphorus Metabolism Disorders
Metabolic Diseases
Bone Diseases, Metabolic
Bone Diseases
Musculoskeletal Diseases
Rickets
Calcium Metabolism Disorders
Vitamin D Deficiency
Avitaminosis
Deficiency Diseases
Malnutrition
Nutrition Disorders
Hyperparathyroidism, Secondary
Hyperparathyroidism
Parathyroid Diseases
Endocrine System Diseases

ClinicalTrials.gov processed this record on September 29, 2014