Study of Dietary N-3 Fatty Acids in Patients With Retinitis Pigmentosa and Usher Syndrome
Primary Purpose
Usher Syndrome, Retinitis Pigmentosa
Status
Terminated
Phase
Locations
United States
Study Type
Observational
Intervention
Sponsored by
About this trial
This is an observational trial for Usher Syndrome focused on measuring Usher syndrome, ophthalmologic disorders, rare disease, retinitis pigmentosa
Eligibility Criteria
PROTOCOL ENTRY CRITERIA: Retinitis pigmentosa, including: Usher syndrome (types I and II) Simplex The following inheritance patterns eligible: X-linked recessive; Autosomal dominant; Autosomal recessive
Sites / Locations
- Oregon Health Sciences University
Outcomes
Primary Outcome Measures
Secondary Outcome Measures
Full Information
NCT ID
NCT00004345
First Posted
October 18, 1999
Last Updated
June 23, 2005
Sponsor
National Center for Research Resources (NCRR)
Collaborators
Oregon Health and Science University
1. Study Identification
Unique Protocol Identification Number
NCT00004345
Brief Title
Study of Dietary N-3 Fatty Acids in Patients With Retinitis Pigmentosa and Usher Syndrome
Study Type
Observational
2. Study Status
Record Verification Date
July 2002
Overall Recruitment Status
Terminated
Study Start Date
October 1999 (undefined)
Primary Completion Date
undefined (undefined)
Study Completion Date
undefined (undefined)
3. Sponsor/Collaborators
Name of the Sponsor
National Center for Research Resources (NCRR)
Collaborators
Oregon Health and Science University
4. Oversight
5. Study Description
Brief Summary
OBJECTIVES: I. Examine the concentration of docosahexanoic acid (DHA) and other n-3 fatty acids in plasma, erythrocyte, and adipose tissue in patients with various forms of retinitis pigmentosa and Usher syndrome.
II. Determine the synthesis and catabolism of DHA from linolenic acid in these patients.
III. Determine the synthesis, absorption, and catabolism of DHA under different dietary conditions in these patients.
Detailed Description
PROTOCOL OUTLINE: Patients may participate in one or more of the arms of this study.
Arm I (adipose tissue study): Adipose tissue is collected from the buttocks of patients with Usher II retinitis pigmentosa (RP), patients with non-Usher RP, and control subjects. Dietary histories are obtained from all patients and subjects.
Arm II (isotope study): Patients meeting the same criteria as in arm I receive oral D5-labeled linolenic acid and oral D4-labeled linolenic acid that is dissolved in oil and incorporated into foods. Subjects must avoid eating fish and shellfish during the 35 days of the isotope study. Blood samples are collected at 0, 8, 24, and 48 hours, daily on days 3-7, and then on days 10, 18, and 35.
Arm III (flaxseed oil feeding): Patients with all types of RP and control subjects receive flaxseed oil, a form of linolenic acid, for 12 weeks. Subjects may also receive high oleic safflower oil or olive oil as a control fat for 12 weeks. Subjects complete a diet history at the end of each fatty acid supplementation period. All subjects must follow a diet free of seafood and fish oil supplements.
6. Conditions and Keywords
Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Usher Syndrome, Retinitis Pigmentosa
Keywords
Usher syndrome, ophthalmologic disorders, rare disease, retinitis pigmentosa
7. Study Design
Enrollment
100 (false)
10. Eligibility
Sex
All
Minimum Age & Unit of Time
0 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Eligibility Criteria
PROTOCOL ENTRY CRITERIA:
Retinitis pigmentosa, including: Usher syndrome (types I and II) Simplex
The following inheritance patterns eligible: X-linked recessive; Autosomal dominant; Autosomal recessive
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
William Connor
Organizational Affiliation
Oregon Health and Science University
Official's Role
Study Chair
Facility Information:
Facility Name
Oregon Health Sciences University
City
Portland
State/Province
Oregon
ZIP/Postal Code
97201-3098
Country
United States
12. IPD Sharing Statement
Citations:
PubMed Identifier
32573764
Citation
Schwartz SG, Wang X, Chavis P, Kuriyan AE, Abariga SA. Vitamin A and fish oils for preventing the progression of retinitis pigmentosa. Cochrane Database Syst Rev. 2020 Jun 18;6(6):CD008428. doi: 10.1002/14651858.CD008428.pub3.
Results Reference
derived
Learn more about this trial
Study of Dietary N-3 Fatty Acids in Patients With Retinitis Pigmentosa and Usher Syndrome
We'll reach out to this number within 24 hrs