Study of Dietary N-3 Fatty Acids in Patients With Retinitis Pigmentosa and Usher Syndrome - Full Text View

Purpose

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.

Condition

Usher Syndrome
Retinitis Pigmentosa

Genetics Home Reference related topics:

Lenz microphthalmia syndrome nonsyndromic deafness oculofaciocardiodental syndrome Opitz G/BBB syndrome Peters plus syndrome Usher syndrome X-linked juvenile retinoschisis

MedlinePlus related topics:

Usher Syndrome

U.S. FDA Resources

Study Type:	Observational
Study Design:	Screening

Further study details as provided by National Center for Research Resources (NCRR):

Estimated Enrollment:	100
Study Start Date:	October 1999

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.

Eligibility

Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	Yes

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

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00004345

Locations


United States, Oregon
	Oregon Health Sciences University
	Portland, Oregon, United States, 97201-3098

Sponsors and Collaborators

National Center for Research Resources (NCRR)

Oregon Health and Science University

Investigators


Study Chair:	William Connor	Oregon Health and Science University

More Information

Study ID Numbers:	199/11904, OHSU-2650
First Received:	October 18, 1999
Last Updated:	June 23, 2005
ClinicalTrials.gov Identifier:	NCT00004345
Health Authority:	United States: Federal Government

Keywords provided by National Center for Research Resources (NCRR):

Usher syndrome

ophthalmologic disorders

rare disease

retinitis pigmentosa

Study placed in the following topic categories:

Sensation Disorders

Vision Disorders

Sensorineural hearing loss

Retinitis

Hearing Loss, Sensorineural

Ear Diseases

Usher Syndromes

Pigmentary retinopathy

Signs and Symptoms

Hearing Disorders

Deafness

Retinitis Pigmentosa

Cone rod dystrophy

Abnormalities, Multiple

Eye Diseases, Hereditary

Hearing Loss

Congenital Abnormalities

Retinal Diseases

Retinitis pigmentosa-deafness syndrome

Otorhinolaryngologic Diseases

Eye Diseases

Rare Diseases

Retinal Degeneration

Blindness

Genetic Diseases, Inborn

Neurologic Manifestations

Usher syndrome

Retinal degeneration

Additional relevant MeSH terms:

Pathologic Processes

Disease

Syndrome

Nervous System Diseases

Deaf-Blind Disorders

ClinicalTrials.gov processed this record on September 05, 2008

Sponsors and Collaborators:	National Center for Research Resources (NCRR) Oregon Health and Science University
Information provided by:	National Center for Research Resources (NCRR)
ClinicalTrials.gov Identifier:	NCT00004345