Systemic Glutathione Level in Normal Tension Glaucoma

• Sponsor: The Catholic University of Korea (Other)
• Overall Status: Completed
• CT.gov ID: NCT00570362
• Collaborator: (none)
• Enrollment: 49
• Location: 1
• Duration (Months): 7
• Patients Per Site Per Month: 7

Study Details

Study Description

Brief Summary

The purpose of this study is to evaluate whether systemic glutathione level is decreased in patients with normal tension glaucoma.

Condition or Disease	Intervention/Treatment	Phase
Normal Tension Glaucoma

Detailed Description

Normal tension glaucoma is one of the most common cause of primary open angle glaucoma in Korea. Even though, we still do not know what the cause is. Only IOP-lowering drugs are the currently available therapeutic method. Glutathione is one of the mostly high concentrated intracellular antioxidants. We find apoptosis of neuronal cell in the mouse retina by systemic depletion of glutathione using buthionine sulfoximine. Glutathione is also known to be reduced in primary open angle glaucoma with high IOP. So we are planning to evaluate systemic glutathione level in normal tension glaucoma.

Blood samples will be obtained by venipuncture to the antecubital vein of normal tension glaucoma patients and age-matched normal controls. Five milliliters of blood will be collected in EDTA-treated tubes (to prevent oxidation). Thirty microliters of blood will be then transferred into centrifuge tubes, and will be added 33.3 microliter of 5-sulfosalicylic acid (SSA), 100mg/mL within 10 minutes from the blood collection.Each sample will be then diluted with 936.7 microliter sodium phosphate buffer (pH 7.5), and the content of each tube will be mixed rapidly in a centrifuge at 13,000 rpm for 5 minutes. A portion of supernatant (150 microliter) will be then collected into clean centrifuge tubes and immediately cooled at -70°C. To each well of a 96-well plate, 150 microliter of daily buffer (3 mg NADPH into 10 mL sodium phosphate buffer), 50microliter of DTNB solution, and 25 microliter of standards or samples will be added in quadruplicate, and the plate will be incubated at 37 °C for 3 minutes.Finally, 25 microliter GSSGR will be added to the previous mixture, and the plate will be read at 410 nm using a 96-well plate reader(UV spectrophotometer).

Study Design

• Study Type: Observational
• Actual Enrollment: 49 participants
• Observational Model: Case-Control
• Time Perspective: Cross-Sectional
• Official Title: Evaluation of Systemic Glutathione Level in Patients With Normal Tension Glaucoma
• Study Start Date: Mar 1, 2008
• Actual Primary Completion Date: Oct 1, 2008
• Actual Study Completion Date: Oct 1, 2008

Outcome Measures

Primary Outcome Measures

1. Total Glutathione Levels [Once in the morning.]

   Subjects were instructed to fast from midnight to 8 AM on the morning of the test. All blood samples were obtained by a qualified registered nurse in the morning, between 8 and 10 AM.

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years to 80 Years
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Patients were included in the normal tension glaucoma group according to the following criteria.

Inclusion Criteria (normal tension glaucoma group):

• Clinical Diagnosis of Normal Tension Glaucoma: Patients underwent diurnal IOP phasing and were diagnosed as having normal tension glaucoma(IOP always lesser than 22 mm Hg by applanation tonometry), glaucomatous optic disc cupping on fundoscopic examination, open anterior chamber angles by gonioscopy(Schaffer grade III or more), and repeatable VF defects consistent with the diagnosis of glaucoma, according to results obtained with program 24-2 of the Humphrey Field Analyzer.

• Must be able to provide intravenous blood sampling

Exclusion Criteria (normal tension glaucoma group):

• Narrow iridocorneal angles

• Any evidence of secondary open-angle glaucoma

• Any other ocular disease except cataract

• History of previous intraocular surgery including cataract

• Any other systemic disease except hypertension

The control group was composed of age-matched healthy volunteers who had neither glaucoma nor other ocular diseases such as cataract, diabetic retinopathy or age related macular degeneration. The control group did not show any glaucomatous optic disc cupping on fundoscopic examination or visual field defects with program 24-2 of the Humphrey Field Analyzer. The healthy volunteers in the control group must be able to provide intravenous blood sampling.

Exclusion criteria for both groups:

• Smoking

• History of any chronic systemic disease with presumed low glutathione levels, including autoimmune diseases, alcoholic liver disease, cancer, and diabetes mellitus.

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	College of Medicine, The Catholic University of Korea, St. Mary's Hospital	Seoul		Korea, Republic of	150-713

Sponsors and Collaborators

• The Catholic University of Korea

Investigators

• Study Director: Jung-Il Moon, Professor, Department of Ophthalmology, St.Mary's Hospital, College of Medicine, The Catholic University of Korea

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

• ClinicalTrials.gov Identifier: NCT00570362
• Other Study ID Numbers: Merck-001; CMCEYE-GSH
• First Posted: Dec 10, 2007
• Last Update Posted: Aug 10, 2010
• Last Verified: Dec 1, 2007

• Keywords provided by , ,: Normal tension glaucoma; Glutathione; Antioxidant
• Additional relevant MeSH terms: Glaucoma; Low Tension Glaucoma

Study Results

Participant Flow

Recruitment Details	Patients with normal tension glaucoma attending the glaucoma clinic of the Catholic Eye Center at the St. Mary' Hospital (Seoul, Korea) between June 2008 and October 2008, were recruited for this study. The control group was recruited from other age-gender-matched volunteers.
Pre-assignment Detail	Only subjects who voluntarily wanted to participate in this study were recruited.

Arm/Group Title	Normal Tension Glaucoma Group	Control Group
Arm/Group Description	Patients were diagnosed as having normal tension glaucoma if IOP measurements were lesser than 22 mm Hg by Goldmann applanation tonometry, characteristic glaucomatous cupping of the optic disc on fundoscopic examination, normal open anterior chamber angles by gonioscopy, and repeatable visual field defects consistent with the diagnosis of glaucoma, according to results obtained with program 24-2 of the Humphrey Field Analyzer (Carl Zeiss Meditec, Dublin, CA).	The control group was recruited from other age-gender-matched volunteers, and it was composed of subjects who had never neither glaucoma nor other ocular diseases such as cataract, diabetic ratinopathy, or age related macular degeneration.
Period Title: Overall Study
STARTED	19	30
COMPLETED	19	30
NOT COMPLETED	0	0

Baseline Characteristics

Arm/Group Title	Normal Tension Glaucoma Group	Control Group	Total
Arm/Group Description	Patients were diagnosed as having normal tension glaucoma if IOP measurements were lesser than 22 mm Hg by Goldmann applanation tonometry, characteristic glaucomatous cupping of the optic disc on fundoscopic examination, normal open anterior chamber angles by gonioscopy, and repeatable visual field defects consistent with the diagnosis of glaucoma, according to results obtained with program 24-2 of the Humphrey Field Analyzer (Carl Zeiss Meditec, Dublin, CA).	The control group was recruited from other age-gender-matched volunteers, and it was composed of subjects who had never neither glaucoma nor other ocular diseases such as cataract, diabetic ratinopathy, or age related macular degeneration.	Total of all reporting groups
Overall Participants	19	30	49
Age (Count of Participants)
<=18 years	0 0%	0 0%	0 0%
Between 18 and 65 years	15 78.9%	29 96.7%	44 89.8%
>=65 years	4 21.1%	1 3.3%	5 10.2%
Age (years) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [years]	56.26 (8.48)	52.70 (6.70)	54.08 (7.43)
Sex: Female, Male (Count of Participants)
Female	9 47.4%	10 33.3%	19 38.8%
Male	10 52.6%	20 66.7%	30 61.2%
Region of Enrollment (participants) [Number]
Korea, Republic of	19 100%	30 100%	49 100%

Outcome Measures

1. Primary Outcome

Title	Total Glutathione Levels
Description	Subjects were instructed to fast from midnight to 8 AM on the morning of the test. All blood samples were obtained by a qualified registered nurse in the morning, between 8 and 10 AM.
Time Frame	Once in the morning.

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Normal Tension Glaucoma Group	Control Group
Arm/Group Description	Patients were diagnosed as having normal tension glaucoma if IOP measurements were lesser than 22 mm Hg by Goldmann applanation tonometry, characteristic glaucomatous cupping of the optic disc on fundoscopic examination, normal open anterior chamber angles by gonioscopy, and repeatable visual field defects consistent with the diagnosis of glaucoma, according to results obtained with program 24-2 of the Humphrey Field Analyzer (Carl Zeiss Meditec, Dublin, CA).	The control group was recruited from other age-gender-matched volunteers, and it was composed of subjects who had never neither glaucoma nor other ocular diseases such as cataract, diabetic ratinopathy, or age related macular degeneration.
Measure Participants	19	30
Mean (Standard Deviation) [nmol]	524.02 (231.09)	586.06 (156.08)

Adverse Events

Arm/Group Title	Normal Tension Glaucoma Group		Control Group
Arm/Group Description	Patients were diagnosed as having normal tension glaucoma if IOP measurements were lesser than 22 mm Hg by Goldmann applanation tonometry, characteristic glaucomatous cupping of the optic disc on fundoscopic examination, normal open anterior chamber angles by gonioscopy, and repeatable visual field defects consistent with the diagnosis of glaucoma, according to results obtained with program 24-2 of the Humphrey Field Analyzer (Carl Zeiss Meditec, Dublin, CA).		The control group was recruited from other age-gender-matched volunteers, and it was composed of subjects who had never neither glaucoma nor other ocular diseases such as cataract, diabetic ratinopathy, or age related macular degeneration.
All Cause Mortality
	Normal Tension Glaucoma Group		Control Group
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	/ (NaN)		/ (NaN)
Serious Adverse Events
	Normal Tension Glaucoma Group		Control Group
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/19 (0%)		0/30 (0%)
Other (Not Including Serious) Adverse Events
	Normal Tension Glaucoma Group		Control Group
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/19 (0%)		0/30 (0%)

Limitations/Caveats

[Not Specified]

More Information

Certain Agreements

Principal Investigators are NOT employed by the organization sponsoring the study.

There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.